Newsletter of Australia’s National Animal Health Information System

www.animalhealthaustralia.com.au

Volume 20 | Issue 3 | July to September 2015 | ISSN 1445-9701

Contents2013–14 animal health survey 02 of Norfolk Island

Australia’s offshore surveillance activities 03

Wildlife Health Australia 04

Aquatic Animal Health 07

State and territory reports 08

Quarterly statistics 23

NAHIS contacts 32

Animal Health SurveillanceQ U A R T E R L Y

Message from the Australian Chief Veterinary Officer

Welcome to the third Animal Health Surveillance Quarterly report for 2015.

The 83rd General Session of OIE Delegates, held in Paris on 24–29 May 2015, generated important outcomes for Australia.

Recent activities have highlighted the connections in our world, both between animal health and other health sectors and between the many private and public participants in our animal health system.

This quarter, I attended the KVF Jubb Fellowship Lecture, ‘Wildlife health in the 21st century’, hosted by the University of Melbourne and the seminar, ‘Taking a wider view: advancing the One/Eco Health agenda in Australia’, hosted by the University of Sydney. Both events highlighted the intersections between wildlife health and public health, food security and global ecological imperatives. Cross-sectoral collaborations will be critical to the future acceptability and success of Australia’s animal production systems and I look forward to building on our existing connections to support a shared future.

I was privileged to take a field trip to Queensland in August, visiting a free-range poultry farm, an aquaculture hatchery, a cattle farm and the Royal Queensland Show. Those I met graciously shared their views on different aspects of biosecurity and the disease concerns affecting Australian livestock owners and producers. The trip enhanced my understanding of current farmer perspectives and key animal health issues within their working context.

In September, I attended the World Organisation for Animal Health (OIE) seminar, ‘Development of public–private partnerships to support veterinary services’, in Mongolia. This seminar reminded me how fortunate Australia is to have a number of well-established public–private partnerships to support its animal health system. I feel proud that Australia continues to serve as a world leader in this area.

As usual, this quarterly report covers monitoring and surveillance from the states and territories and in Australian wildlife, and investigations of disease incidents.

Dr Mark Schipp Australian Chief Veterinary Officer

Animal Health Surveillance Quarterly | Volume 20 | Issue 3

the ‘road herd’. They are excluded from the centre of the only township, the airport, the national park and private property by the use of cattle grids and fencing. The island’s stock inspector advised that the ‘road herd’ had through-the-fence contact with all but three cattle herds maintained on private land. Twice yearly, the ‘road herd’ is mustered for drenching, copper supplementation and management, including weaning and removal of bull calves to private property. We took advantage of these musters to collect samples from the road herd and two additional private herds.

All livestock were visually inspected for evidence of clinical disease. TB testing was conducted on a random sample of 155 animals older than 2 years from the road herd and two of the isolated private herds. Animals were tested using the single intradermal comparative test administered in the mid-neck region because a history of reactions to Mycobacterium avium was reported from previous animal health surveys conducted on Norfolk Island. All cattle tested negative for bovine TB.

Blood samples were collected from 161 cattle and transported to Australia where they were tested for leptospirosis, BVDV, Q fever, enzootic bovine leucosis (EBL) virus, IBR and BJD. On a subsequent trip, faecal and blood samples were collected from three cattle that returned a positive or inconclusive test to BJD in 2013 and from 10–12 herd mates, older than 2 years, of each of these three cattle in question. All animals tested negative for bovine TB, BJD, Brucella abortus, Q fever, EBL virus and Leptospira hardjobovis. However, the cattle population was positive for IBR, BVDV and Leptospira pomona.

The health status of the cattle was confirmed through examination of the Norfolk Island Veterinary Clinic records, a review of historical animal health surveys conducted on Norfolk Island, the Australian Government Department of Health’s notifiable diseases reports from Norfolk Island (for zoonoses), meat inspection records and an insect vector survey. No evidence was found for the presence of the vectors for bluetongue virus, babesiosis, anaplasmosis, bovine ephemeral fever (BEF) or Akabane virus.

The 2013–14 animal health survey found no pests or diseases of biosecurity concern to Australia in the Norfolk Island cattle population.

02

Norfolk Island is a self-governing territory of Australia located in the

Pacific Ocean. It is approximately 1400 km from the Australian mainland and 730 km from New Zealand. In 2013, the then Australian Government Department of Regional Australia, Local Government, Arts and Sport contracted the then Australian Government Department of Agriculture to conduct a survey of animal and plant health on Norfolk Island. The animal health component was conducted over 2013–14 by Iain East and Richard Rubira from the Animal Health Policy Branch of the Department of Agriculture. One of the aims of the survey was to advise whether Norfolk Island could come inside the Australian quarantine barrier, so the focus of the survey was on pests and diseases of production and domestic animals that might be present on Norfolk Island that were not present in Australia.

2013–14 animal health survey of Norfolk IslandIain East and Richard Rubira, Australian Government Department of Agriculture and Water Resources

The animal population of Norfolk Island is approximately 1700 cattle; 100 individuals each of sheep, pigs, horses, dogs and cats; 1800 domestic chickens on a single layer farm and numerous backyard flocks; and an estimated 3000 feral chickens. This report focuses on the survey of the cattle population.

An examination of importation records revealed that Norfolk Island had only imported animals and animal products from either Australia or New Zealand for more than 50 years. This meant that the most likely source of any pests or diseases of biosecurity concern to Australia would originate in New Zealand. Selection of pests and diseases for inclusion in the survey was also guided by the existing import conditions into Australia for cattle originating from Norfolk Island.

For Norfolk Island, the only cattle diseases of concern were bovine tuberculosis (TB) and bovine Johne’s disease (BJD). Because the contract with the Department of Regional Australia, Local Government, Arts and Sport emphasised the requirement to test for zoonoses, testing of cattle for brucellosis, leptospirosis and Q fever were added to the panel of diseases examined. To encourage cooperation from the cattle owners of Norfolk Island, the survey covered additional diseases, including infectious bovine rhinotracheitis (IBR) and bovine viral diarrhoea virus (BVDV1). Both these diseases had previously been reported from Norfolk Island.

Of the 1700 cattle on Norfolk Island, 255 wander freely over Crown land, including roadsides. These cattle are referred to as

1 Only BVDV type 1 (BVDV-1) is present in Australia. The severe BVDV-2 form in Europe and North America has not been found in Australia.

Photo: Dollar Photo Club

Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Australia’s offshore surveillance activitiesPatrick Cass, Australian Government Department of Agriculture and Water Resources

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The animal health systems in both PNG and Timor-Leste are developing and both countries have significant pests and diseases of animals currently exotic to Australia, such as screw-worm fly in PNG and classical swine fever and Aujeszky’s disease in Timor-Leste.

Australia regularly collaborates with its near neighbours Papua New

Guinea (PNG) and Timor-Leste to undertake field surveillance for significant animal diseases. The Australian Government Department of Agriculture and Water Resources conducts these activities in partnership with the PNG National Agriculture Quarantine and Inspection Authority and the Timor-Leste Ministry of Agriculture and Fisheries (MAF) under memoranda of understanding.

Offshore surveillance activities conducted by the Australian Government department in these countries aim to:• gatherinformationaboutthepresence

and potential entry of significant exotic animal diseases

• raiseawarenessofanimalhealthandbiosecurity issues

• buildcapacitywithincounterpartagencies to manage animal health

• developprofessionalrelationshipsbetween the department and counterpart agencies.

The animal health systems in both PNG and Timor-Leste are developing and both countries have significant pests and diseases of animals currently exotic to Australia, such as screw-worm fly in PNG and classical swine fever and Aujeszky’s disease in Timor-Leste. The proximity of these countries to Australia, as well as familial and cultural ties, makes them important from a biosecurity perspective. For example, traditional movement of people and goods occurs between southern coastal villages of PNG and the Torres Strait Protected Zone under the Torres Strait Treaty between Australia and PNG.

During a field survey, information on the animal health status of an area is gathered through a combination of formal and informal interviews with community members and collection of biological samples for laboratory testing. Samples from a variety of species are sent to the CSIRO Australian Animal Health Laboratory for testing of significant animal diseases of mutual interest to Australia and PNG or Timor-Leste. This includes testing for foot-and-mouth disease, avian influenza and transmissible gastroenteritis. Where possible, duplicate samples are sent to the animal health laboratory of PNG or Timor-Leste where they can be tested for the same diseases and other endemic diseases. Duplicate testing provides an important opportunity to develop local diagnostic capacity.

The field survey teams include veterinarians from Australia (from the department’s Animal Health Policy Branch and Northern Australia Quarantine Strategy) and counterpart governments (PNG or Timor-Leste).

Field surveys offer local survey team members an opportunity to develop their skills in public speaking, sample collection from various species and performing necropsies (if the survey team finds any sick or dead animals in the communities visited). Survey team members have an opportunity to develop networks within these communities, leading to an increase in the level of passive surveillance. This is

particularly useful when surveying remote areas of the country that are rarely visited by local officers due to logistical difficulties. The location of field surveys is decided by mutual agreement. Field surveys target those areas that are considered a higher biosecurity risk or at higher risk of an animal pest or disease incursion, particularly border areas and coastal areas with higher volumes of international vessel movements. Other factors taken into account include the safety and security of the survey team, the logistics of getting in and around the area, the infrastructure and services available in the area, weather and environmental conditions.

In August 2015, the Australian Government department collaborated with MAF to conduct an animal health field survey primarily focused on the Special Administrative Region of Oecusse, an exclave of Timor-Leste in the western part of the island of Timor. Oecusse is bordered on three sides by West Timor (Indonesia) and by the sea to the north. The survey team consisted of three Australian veterinarians, six officers from central MAF and, variously, local MAF officers. The team visited four villages across the district and one of three official border-crossing points between Oecusse and Indonesia.

As this was the first collaborative survey of Oecusse since 2010, it provided both agencies with valuable information to help assess the biosecurity risks in this unique area. In particular, advice from all the communities surveyed confirmed a large volume of movements across both land and sea routes into nearby Indonesian territory. Most movements reportedly related to family ties across the border, and meat and live animals are often brought into Oecusse by these routes. This cross-border trade provides a direct pathway for the introduction of animal pests and diseases into Timor-Leste and potentially, indirectly, into Australia. The survey results provided both agencies with an indication of the animal health status of West Timor as these regular movements are likely to result in an equivalent status on both sides of the border.

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Wildlife Health AustraliaTiggy Grillo, Keren Cox-Witton and Sam Gilchrist, Wildlife Health Australia; and Iain East, Australian Government Department of Agriculture and Water Resources

04

Animal Health Laboratory. There was no evidence of flaviviruses (Japanese encephalitis serogroup) based on immunohistochemistry, and virus isolation was negative. Investigation of wild birds presenting with similar clinical or histological findings is encouraged, including laboratory testing to rule out specific diseases of concern (e.g. AI, APMV and flaviviruses).

Table 2 Wild bird disease investigations reported into eWHIS, July–September 2015

Bird order Common name for bird ordera Events reportedb

Anseriformes Magpie geese, ducks, geese and swans 1

Caprimulgiformes Frogmouths, nightjars, owlet-nightjars, swifts

1

Charadriiformes Shorebirds 1

Columbiformes Doves and pigeons 3

Falconiformes Falcons 1

Passeriformes Passerines or perching birds 5

Pelecaniformes Pelicans 5

Psittaciformes Parrots and cockatoos 36

Strigiformes Typical owls and barn owls 1

a Common names adapted from: del Hoyo and Collar (2014) HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1 – Non-passerines. Lynx Editions, Barcelona. (Courtesy of the Australian Government Department of the Environment).

b Disease investigations may involve single or multiple bird orders (e.g. mass mortality event).

Table 1 Number of disease investigations reported into eWHIS, July–September 2015a

Batsb Birds MarsupialsFeral

animalsSnakes and

lizardsFreshwater

turtles MonotremesMarine

mammalsMarine turtles

54 54 19 1 0 1 0 2 1

a Disease investigations may involve a single animal or multiple animals (e.g. mass mortality event).

b The majority of bat disease investigations are single bats submitted for Australian bat lyssavirus testing.

Wild bird mortality events — Newcastle disease and avian influenza exclusionWHA received 54 reports of wild bird mortality or morbidity from around Australia in July–September 2015. A breakdown of the bird orders represented is presented in Table 2. Reports and samples from sick and dead birds are received from members of the public, private practitioners, universities, zoo wildlife clinics and wildlife sanctuaries. Avian influenza (AI) was excluded by polymerase chain reaction (PCR) testing for influenza A in 14 of the events as part of Australia’s general (sick and dead bird) AI surveillance program. AI exclusion testing was not warranted in the remaining 42 events, based on clinical signs, history, prevailing environmental conditions or other diagnoses. In addition, avian paramyxovirus was excluded in 14 events by PCR testing specific for Newcastle disease (ND) virus and/or pigeon paramyxovirus 1 (PPMV-1).In Victoria, an Australian raven (Corvus coronoides) presented to the Australian Wildlife Health Centre at Healesville Sanctuary in August. The very thin bird displayed marked ataxia and was euthanased. Histopathology indicated severe chronic nonsuppurative necrotising panencephalitis. AI, West Nile virus and avian paramyxovirus 1 (APMV-1) were excluded by PCR at CSIRO Australian

Wildlife Health Australia (WHA)2 is the peak body for wildlife health in

Australia. WHA was established as the Australian Wildlife Health Network (AWHN) in 2002 as an Australian Government initiative to coordinate wildlife health surveillance information across Australia, to support Australia’s animal health industries, human health, biodiversity, trade and tourism. WHA collates information from multiple sources into a national database — the Wildlife Health Information System (eWHIS)3 — including submissions by WHA subscribers, state and territory WHA coordinators, researchers, and zoo and sentinel clinic veterinarians. In July to September 2015, 132 wildlife disease investigation events were reported into eWHIS (Table 1). This report details some of the disease and mortality events in free-living wildlife recorded in eWHIS this quarter. WHA thanks all those who submitted information for this report.

2 www.wildlifehealthaustralia.org.au/Home.aspx

3 www.wildlifehealthaustralia.com.au/ProgramsProjects/eWHISWildlifeHealthInformationSystem.aspx

Avian influenza surveillanceAustralia’s National Avian Influenza Wild Bird (NAIWB) Surveillance Program comprises two sampling components: pathogen-specific, risk-based surveillance by sampling of apparently healthy, live and hunter-killed wild birds; and general surveillance by investigating significant unexplained morbidity and mortality events in wild birds, including captive and wild birds within zoo grounds (with a focus on exclusion testing for AI virus subtypes H5 and H7). Samples from sick or dead birds are discussed above. Sources for targeted wild bird surveillance data include state and territory government laboratories, universities and samples collected through the Northern Australia Quarantine Strategy.

Between July 2014 and June 2015, pathogen-specific, risk-based surveillance occurred at sites in New South Wales, Queensland, Victoria, Tasmania, South

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Image courtesy Karrie Rose, Australian Registry of Wildlife Health

Initial presenting signs included swollen eyes and the turtles were thin. Many animals had a slight clear nasal discharge and some presented with hind limb paresis. On gross necropsy, animals were thin, had bilateral swollen eyelids and anterior uveitis, and some animals had tan foci on the skin of the ventral thighs. Histopathologically, inflammation extended from the eyelids, peri orbital tissues and sinuses, sometimes extending along the olfactory–optic nerve into the meninges. On histology, there was evidence of fibrinonecrotising splenitis and nephritis and multisystemic fibrinoid vasculopathy. All lesions appeared to be acute. PCR and other tests, including virus isolation, excluded a range of potential infectious aetiologies, including ranavirus, adenovirus, paramyxovirus (ferlavirus), herpesvirus, mycoplasma, chlamydia and Trichomonas. Water samples collected from four Bellinger River sites (two upstream and two downstream of the affected area) by the NSW Environment Protection Agency found no evidence of hydrocarbons or pesticides, including organochlorines, organophosphates and pyrethroids.

The Australian Registry of Wildlife Health at Taronga Conservation Society Australia conducted gross and histological examinations of affected animals and coordinated the diagnostic investigation that spanned multiple state agencies and academic institutions. In July 2015, scientists at the Elizabeth Macarthur Agricultural Institute detected a novel virus in tissues of affected turtles. Extensive testing showed very high levels of the virus in the tissues of animals with the most severe lesions, suggesting a major role for this virus. Further work is being undertaken to characterise the virus, determine its significance in the pathogenesis of disease and develop further testing capabilities.

When the disease was first detected, the upper catchment area of the Bellinger River (within the New England National Park) was closed (NSW OEH, 2015). Affected turtles were removed from the river to minimise the potential for disease transmission to other watercourses. Public information signs were installed at 17 sites along the river, providing biosecurity and hygiene advice to members of the public using canoes and kayaks, swimming or fishing in the river. NSW Department of Primary Industries and Wildlife Health Australia circulated specific biosecurity messaging, alerting veterinarians to be aware of any reports of similar findings in freshwater turtles.

With the limited distribution of M. georgesi, the high level of morbidity (at least 25% of the known population) and a case fatality rate approaching 100%, the NSW Scientific Committee (2015) made a Preliminary Determination to list the species as Critically Endangered under the Threatened Species Conservation Act 1995. A small number of healthy M. georgesi were removed from the river in autumn 2015 for a captive breeding program and have remained healthy.

M. georgesi are inactive during the cooler months from April to September. Preliminary surveys are planned for the spring to assess the extant turtle population.

The response, investigation and management of this event involved multiple government and nongovernment agencies and organisations, including Australian Registry of Wildlife Health, Bellingen Shire Council, CSIRO Australian Animal Health Laboratory, Elizabeth Macarthur Agricultural Institute, NSW Department of Primary Industries, NSW Environment Protection Authority, NSW Health, NSW Local Land Services, NSW Office of Environment and Heritage, NSW National Parks and Wildlife Service, NSW Regional Operations Group and Heritage Division, Taronga Conservation Society Australia, Wildlife Health Australia and multiple university researchers, private veterinarians and international experts.

See the Bellinger Shire Council website4 for further information or the NSW Department of Primary Industries website5 for Bellinger River snapping turtle response documents.

4 www.bellingen.nsw.gov.au/news/bellinger-river-snapping-turtle-deaths-latest-news

5 www.dpi.nsw.gov.au/biosecurity/animal/wildlife-and-feral-animals

Australia, the Northern Territory and Western Australia. Samples were collected from 7244 birds, with the majority collected from waterbirds (ducks and waders). No highly pathogenic AI viruses have been identified. However, surveillance activities continue to find evidence of a wide range of subtypes of low pathogenic AI viruses, including low-pathogenic H5 and H7, as well as H2-H4, H6 and H8-H11. The findings support the need for continuing surveillance activities in wild birds and reiterate the need for poultry producers to remain alert and ensure that appropriate biosecurity arrangements and effective risk reduction measures for AI are in place at their premises. The NAIWB Surveillance Program will continue in 2015–16.

During the quarter, pathogen-specific, risk-based surveillance occurred at sites in New South Wales, Queensland and Tasmania with faecal environmental swabs collected from 581 waterbirds. Results are pending.

Bellinger River snapping turtle mortality eventReported in collaboration with Barbara Moloney and Sarah Britton, NSW Department of Primary Industries; and Sarah Matthews, the University of Sydney.

Investigations into a severe mortality event involving Bellinger River snapping turtles (Myuchelys georgesi) commenced following a report from local kayakers on 18 February 2015 of approximately 50–70 dead freshwater turtles (Moloney et al, 2015). Over the course of the investigation and since 14 February 2015, an estimated 432 M. georgesi have been observed dead or dying. Live affected turtles were described as slow moving and unable to see. M. georgesi is a unique species of freshwater turtle found only in small sections of the Bellinger and Kalang rivers. A 2007 survey (Spencer et al, 2007) estimated the total population of this species to be between 1500 and 4500 individuals. M. georgesi relies largely on its sight for feeding and the onset of blindness prevented normal foraging. Smaller numbers of other turtle species, including Emydura macquarii and Chelodina longicollis, are present in these rivers but none of these species have been observed affected. In the lead up to the mortality event, river conditions had been different. A severe heat episode in early December 2014 reportedly elevated water temperatures, and severely low water levels were followed by two minor floods, one in late December 2014 and another in late January 2015.

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Eastern grey kangaroo mortalities — starvationMore than 300 unwell and dead juvenile eastern grey kangaroos (Macropus giganteus) were reported by rangers and wildlife carers in New South Wales and the Australian Capital Territory during July, August and early September 2015. Reports were received from across a large geographical area, including locations to the north (Mulligans Flat Woodland Reserve and Bywong), east (Wamboin, Queanbeyan and Bungendore) and south-west (Tidbinbilla Nature Reserve, Namadgi National Park and Gudgenby Homestead) of Canberra.

The majority of affected kangaroos were subadult juveniles (up to 15 kg, 18–21 months of age). Clinically, kangaroos were thin and weak with poor coat condition and pale mucous membranes. Affected animals failed to move when approached. Individuals brought into rehabilitation died despite supportive care. Haematology and biochemistry results from seven affected animals in the Australian Capital Territory found all animals to be anaemic (some regenerative) with mild-to-marked elevations in creatine kinase, and many hypoproteinaemic and hypoalbuminaemic.

Gross post mortem and histological examinations revealed a range of findings including reduced or no subcutaneous, abdominal or thoracic adipose tissue to severe chronic emaciation, anaemia, hypoproteinaemia, loss of muscle mass, reduced bone marrow cellularity, and reduced or no colloid in follicles of the thyroid. Gastrointestinal parasite burdens — some known to be associated with clinical signs of anaemia and hypoproteinaemia — were noted. Parasite species included Globocephaloides trifidospicularis associated with clinical signs of anaemia, hypoproteinaemia and oedema (facial swelling); Labiosimplex spp.; Rugopharynx australis; Cloacina spp.; Paramacropostrongylus toraliformis; Pharyngostrongylus kappa; Alocostoma clelandi; Macropoxyuris spp.; Eimeria spp.; and an unidentified protozoan species associated with villous atrophy and inflammation. Gastrointestinal parasites are not an unusual finding in this age class of animals. Further histological examinations performed by NSW Department of Primary Industries at the Elizabeth Macarthur Agricultural Institute and the Australian Registry of Wildlife Health found no evidence of babesiosis, phalaris toxicity or toxoplasmosis.

The cause of the mortalities is considered multifactorial; influences include over population, under nutrition, cold stress and parasitic burden, with starvation related to restricted food availability the key driving factor. In areas where mortalities were recorded, there had been a shortage of feed due to low temperatures and low rainfall over winter. The detrimental health effects of common gastrointestinal parasites normally found in kangaroos are exacerbated when food is limited.

Seasonal mortalities of subadult eastern grey kangaroos have been previously observed during July, August and early September over the past 20 years in the Australian Capital Territory. Similar seasonal die-offs have been reported in Victoria and New South Wales (Dawson, 2012). Reports describe the complex interaction of climatic conditions and poor pasture growth, culminating in stress-related mass mortalities. The mortalities impose a natural population regulatory effect and serve to protect the population when food resources are restricted.

A number of agencies and organisations have been involved in the response and investigation into the 2015 events, including ACT Parks and Conservation, Australian Registry of Wildlife Health, CSIRO, NSW Department of Primary Industries, NSW Office of Environment and Heritage, NSW Wildlife Information, Rescue and Education Service Inc (WIRES), Tidbinbilla Nature Reserve and Wildlife Health Australia.

Australian bat lyssavirusReports to WHA for the July–September quarter included 54 bats tested for Australian bat lyssavirus (ABLV) from New South Wales, Northern Territory, Queensland, Victoria and Western Australia. Bat submissions were made for a variety of reasons:• 16casesinvolvedcontactorsuspected

contact with the potential for ABLV transmission to humans; of these

− 6 were also associated with trauma (e.g. barbed wire entanglement)

− 2 involved contact with a pet dog or cat − the remainder had no further history

reported• 28casesinvolvedcontactwithapetdog

(23 bats) or cat (4 bats) or both (1 bat)• 2batsdisplayedneurologicalsigns

(aggression, abnormal vocalisation, hindlimb paralysis, nystagmus), one of which also had evidence of trauma

• 3caseswereassociatedwithtrauma (e.g. barbed wire or fishing line entanglement)

• 1batwasfounddead• 4batshadnofurtherhistoryreportedat

this time.

During the quarter, one black flying fox (Pteropus alecto) from Queensland was confirmed positive for ABLV by PCR testing for pteropid ABLV ribonucleic acid (RNA). The flying fox was found on the ground at a farmer’s market in Brisbane. Potentially dangerous human contact was reported and an experienced public health official provided appropriate counselling and information.

More information on ABLV testing of bats in Australia is available in ABLV Bat Stats.6

ReferencesDawson, TJ (2012). Kangaroos. Chapter 3—Population structure, dispersal and mortality. pp. 59–60. CSIRO Publishing, Collingwood, Victoria.

Moloney B, Britton S and Matthews S (2015). Bellinger River snapping turtle mortality event 2015: epidemiology report. October 2015. NSW Department of Primary Industries, Orange, New South Wales. www.bellingen.nsw.gov.au/sites/bellingen/files/public/images/documents/bellingen/Environment/BRST_Mortality_Event_DPI_Epidemiology_Report_2015_Final%20Copy.pdf

NSW OEH (2015). Bellinger River turtle deaths: factsheet March 2015. NSW Office of Environment & Heritage, Sydney, New South Wales. www.dpi.nsw.gov.au/__data/assets/pdf_file/0011/553358/factsheet-bellinger-river-turtle-deaths.pdf

NSW Scientific Committee (2015). Preliminary determination—Bellinger River snapping turtle, 28 August 2015. NSW Scientific Committee, Hurstville, New South Wales. www.environment.nsw.gov.au/resources/threatenedspecies/determinations/PDBellRiverSnapTurtle.pdf

Spencer R-J, Georges A and Welsh M (2007). The Bellinger River Emydura: ecology, population status and management. Unpublished report to NSW National Parks and Wildlife Sservice by Institute of Applied Ecology, University of Canberra, Canberra.

6 www.wildlifehealthaustralia.com.au/ProgramsProjects/BatHealthFocusGroup.aspx

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Photo: Dollar Photo Club

Aquatic Animal HealthYuko Hood, Australian Government Department of Agriculture and Water Resources

Risk-based on-arrival ornamental fish health surveillance and pathway analysis

Australia has a biosecurity policy for importation of ornamental fish that

includes pre-border health certification and mandatory post-arrival quarantine in registered quarantine-approved premises. The current system relies on fish exhibiting clinical disease during post-arrival quarantine. While these measures aim to mitigate the risk of pathogen incursion, they do not manage risks related to entry of pathogens via subclinical infection. For example, the importation of live ornamental fish is considered to be a source for the introduction into Australia of goldfish herpesvirus and enteric septicaemia of catfish (ESC) (caused by Edwardsiella ictaluri), and megalocytiviruses are periodically detected in imported tropical freshwater species. These diseases often persist as subclinical infections and in some cases have been detected after imported ornamental fish have passed the normal quarantine and health requirements.

While facilitating safe trade, the Australian Government Department of Agriculture and Water Resources needs to address risks unique to the ornamental fish trade. These risks are associated with a wide range of potential disease agents, their prevalence in a large number of host species from many regions (more than 4000 species of ornamental fish are traded internationally), rapidly changing patterns of disease epidemiology and the constant emergence of new diseases. Many fish species can carry pathogens in a subclinical state, adding to the complexity of reducing risks of the introduction of exotic pathogens.

To address these challenges, the department is reforming its current system for managing the biosecurity risks from live ornamental fish imports. The reform encompasses the current post-arrival quarantine arrangements and fee structure, and development of innovative surveillance methods for at-source management of risks associated with all imported ornamental fish.

One outcome of the project is the introduction of on-arrival health surveillance to allow the department to monitor the performance of international authorities and exporters in meeting the health requirements for ornamental fish exported to Australia. The system requires a risk-sensitive program to monitor the risk of several target pathogens in subclinically infected fish (‘healthy fish’ stream) and provides intelligence about changing patterns of disease epidemiology and emerging diseases through syndromic surveillance (‘unhealthy fish’ stream).

Within the healthy fish stream, the Centre of Excellence for Biosecurity Risk Analysis (CEBRA) is collaborating with the department to develop an algorithm, based on a continuous sampling plan (CSP) (Dodge, 1943), to advise the department of the appropriate sampling rate for the healthy fish pathways. Each pathway is defined by its unique combination of fish group, importer, exporter and exporting country. This pathway of imports is subject to risk-based sampling and specific pathogen laboratory testing to detect subclinically infected fish. Specified pathogens include spring viraemia of carp virus (SVCV), Aeromonas salmonicida and megalocytiviruses, all of which are considered to be exotic to Australia. The department has commenced a series of

risk-based on-arrival fish health surveillance trials with the long-term goal being to verify the pre-export certifications made by the overseas certifying authorities. A phased approach has been taken for adoption and implementation of the CSP. CSP algorithms for various monitoring pathways will be developed using data collected and analysed from all the trials. Through this process, operational, financial and infrastructural requirements for the proposed system will be refined.

In the unhealthy fish stream, the department intends to develop a syndromic surveillance system that will collect and analyse information at the border, by visual inspection on clinical signs, and at the laboratory, by histopathological examination. This system will enable Australia to better monitor the health status and risk profile of fish from a particular source and increase the likelihood of detecting new or emerging pathogens.

The department, in conjunction with CEBRA, organised an expert elicitation workshop aimed at establishing a visual health index and a histopathology index for the unhealthy fish stream. More than 30 government and private aquatic animal health specialists, veterinary pathologists, fish inspectors and importers participated in the workshop. The initial two sets of indexes developed from the outcomes of the workshop will be entered into a computerised disease detection program that will alert the department on the detection of trends and patterns in symptoms of known or emerging diseases. The system will allow adjustment over time, with new information provided by ongoing data and pathway analyses.

A detailed plan for adoption and implementation of the risk-based on-arrival fish surveillance and pathway analysis system will be developed following completion and evaluation of all phases of the trials. This is a significant challenge but the department will ensure all suggested and planned changes to the current practices are evidence based and well communicated throughout its development.

ReferenceDodge, HF (1943). A sampling plan for continuous production. Annals of Mathematical Statistics 14(3): 264–279.

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State and territory reportsUnder the Australian constitution, state and territory governments are responsible for animal health services within their respective borders (jurisdictions). The governments develop and administer legislation governing the surveillance, control, investigation and reporting of disease and chemical residues and contaminants, as well as legislation relating to animal welfare. The governments deliver their services through government-appointed or government-accredited animal health personnel (district veterinarians, regional veterinary officers and local biosecurity officers). They also provide extension services to industry and the community.The ‘State and territory reports’ summarise disease investigations undertaken within jurisdictions and describe a selection of interesting cases. A comprehensive summary of suspect exotic or emergency disease investigations is reported in Table 17 of ‘Quarterly statistics’.Unless otherwise stated, disease events involving wildlife are reported by Wildlife Health Australia.

deprivation, hypocalcaemia, hypomagnesaemia, clostridial infection, peritonitis, lead toxicity and plant poisonings (Solanum spp. and Bryophyllum spp.). Ten investigations involved sheep where alternate diagnoses included hypocalcaemia and urea toxicity. One pig and one horse investigation found no alternate diagnosis.

Immunochromatographic tests (ICT) were negative in five sheep investigations, 16 cattle investigations and each of the horse and pig investigations.

Botulism outbreak in a small beef herdThe Mudgee district veterinarian investigated a case where 8 out of 19 unvaccinated six-year-old non-lactating adult cattle died over a week. Two cows and one bull in the herd were lying down and unable to rise. During the property investigation, the veterinarian noticed a sheep carcase near a dam where the cattle drank.

The deceased cows could not be necropsied. All had minimal or no signs of struggle before death and no obvious external pathology.

Two of the three recumbent cattle were on their sternums with hindlimbs splayed out; one animal was lying on its side and near death. The menace response (reflex blinking in response to the rapid approach of an object) was decreased in one animal and absent in another. There was no tongue protrusion but there was moderate eye

Government veterinarians investigate significant disease events around

NSW that have syndromes of sudden or unexplained deaths, and/or significant morbidity, where a notifiable disease may be suspected in any species, including wildlife.

During this quarter, government veterinary officers conducted more than 500 field investigations, of which 421 resulted in laboratory accessions (Figure 1).

During the quarter, the state veterinary diagnostic laboratory processed approximately 1316 submissions from diagnostic field investigations by both government and private veterinarians. Of these, 191 submissions were from private veterinarians where the government laboratory conducted testing for notifiable diseases. More than 50% of these were for Hendra virus in horses, 6% for ABLV in bats, 16% for Brucella suis in dogs and 12% were from the poultry industry to exclude emergency diseases.

The following case reports are a selection of field investigations chosen to reflect the range of livestock disease incidents during the quarter.

Anthrax exclusionsThere were no cases of anthrax in New South Wales during the quarter.

There were 42 exclusions of anthrax where livestock deaths were investigated. Thirty investigations involved cattle where alternate diagnoses included water

Rory Arthur, New South Wales Department of Primary Industries

New South Wales

Figure 1 Number of field disease investigations resulting in submissions to the government laboratory in New South Wales, July–September 2015

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Animal Health Surveillance Quarterly | Volume 20 | Issue 3 09

protrusion in all animals, giving a ‘startled’ appearance. This was presumably due to paralysis of the eye muscles and eyelids. All three affected cattle were euthanased because of their poor prognosis and welfare, and two were necropsied.

Both animals had full rumens, with fibrous contents and little liquid. The large intestinal contents were ‘dry’, with small amounts of mucus, and fresh and digested blood, indicating decreased gastrointestinal motility and dehydration.

Samples for laboratory diagnosis were collected from the two cows. Bone, pieces of partly broken down spinal cord and several maggots were collected from the sheep carcase.

At the State Diagnostic Veterinary Laboratory, fresh kidney samples from each necropsied animal tested negative for lead. Histopathological testing of kidney, liver and intestinal samples revealed nothing specific.

Both the sheep bone and the maggots from the sheep carcase were positive on an ELISA test for botulinum toxin antigen. A fresh liver sample from a necropsied cow tested positive for botulinum toxin. Detection of botulinum toxin in both the sheep carcase and the cow liver sample

allowed a definitive diagnosis of botulism in this case.

This case highlighted some typical features of the clinical presentation of botulism in cattle, such as eye protrusion and constipation.

The cattle had probably been poisoned from chewing the bones of the dead sheep. After the remaining cattle were moved to another paddock and vaccinated, there were no more losses.

Another new strain of rabbit calicivirusA new strain of rabbit calicivirus, known as rabbit haemorrhagic disease type 2 virus (RHDV2), was confirmed in a wild rabbit in the Australian Capital Territory in July this year. Since then, RHDV2 has been found in isolated locations around the Australian Capital Territory and New South Wales in pet rabbits, rabbits grown for meat and wild rabbits.

RHDV2 differs from both the variant strain of RHDV first detected in New South Wales last year and the endemic Czech strain that has been present in Australia for the past 20 years. In contrast to the Czech strain, RHDV2 affects younger rabbits, including nestlings.

RHDV2 is most closely related to the European RHDV strain that has successfully spread throughout Europe in recent years. A vaccine specifically against the RHDV2 strain is being developed in Europe but is not yet available. The current commercially available vaccine, when given according to the manufacturer’s instructions, is believed to provide partial protection against RHDV2 in most rabbits. Regular booster vaccinations should be given to domestic pet rabbits to ensure maximum possible protection against this variant.

Virologists at the Elizabeth Macarthur Agricultural Institute are working closely with the Invasive Animals Cooperative Research Centre to identify field strains so that the effects of RHDV2 on rabbit control in Australia can be determined.

Prolonged lead residues in cattle older than 21 monthsIn 2014, along a 1.5 km wide and 100 km long travelling stock reserve in southern New South Wales, 12 out of 1100 weaned calves became blind, uncoordinated and died. The attending veterinarian found fragments of lead in the rumen of one animal, and assays showed lead levels of 9.20 µmol/L (normal < 0.20) in whole blood and 276.00 µmol/L (normal < 2.00) in the kidney.

The source of the lead was not discovered but the cattle were removed to the owner’s property. Blood samples from every animal were tested for lead. Eight calves were found to have lead levels higher than the maximum residue limit (MRL) of 0.24 µmol/L and were not allowed to enter the human food chain.

The affected animals were detained and re-tested 12 months later. Three of the cattle still had lead levels in excess of the MRL.

The cattle were tested again 9 months later and one still had blood lead levels in excess of the MRL and another two had detectable levels. The owner chose to have the steer with the blood level greater than the MRL destroyed and its carcase buried. At necropsy, four visible fragments of lead (1–2 × 1–2 × 3–4 mm) were seen among the villi of the rumen’s lining.

Although the initial lead level of the animal with persistent lead levels was quite high, the steer had grown significantly and was probably twice the weight that it was when it first ingested the lead (from 350 to 700 kg estimated body weight). The persistent presence of lead in the rumen was a factor in the high levels of lead in that animal.

Photo: Dollar Photo Club

10 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Pneumonia in steersThis investigation is an example of public and private veterinarians working together to achieve the diagnosis, treatment and management of a disease event. A government veterinarian conducted the initial investigation and ongoing treatment and management of affected livestock were handled by a local veterinary practice.

Bacterial pneumonia was found to be the cause of death in 4 out of 50 mixed-breed steers, aged 15 months, near Inverell in northern New South Wales. The steers were grazing oats and were up to date with their five-in-one vaccinations.

The district veterinarian was presented with three steers: one dead, one dying and one clinically affected with a fever (39.4°C) that was weak and staggering. The dying steer had a high fever (40.2°C) and was euthanased.

A necropsy of the two dead steers by the district veterinarian revealed acute pneumonia. Areas of reddening and haemorrhage were evident in the smaller ventral lung lobes. Pneumonia was diagnosed from gross pathology and clinical signs.

When consulted for treatment options, the private veterinarian recommended an antibiotic but the owners asked for an alternative cheaper option (tetracycline). The affected steer died overnight and the owner then identified a number of new cases.

The private veterinarian visited the property the next morning to necropsy the dead animal and treat clinically affected animals with tulathromycin. One further death was recorded and four clinically affected steers were treated. Unaffected cattle were examined twice daily and moved to another paddock.

Samples processed at the State Veterinary Diagnostic Laboratory confirmed the diagnosis. Histopathology of the lung samples was consistent with Histophilus sp. infection. Blood tests showed antibody titres for both bovine viral diarrhoea virus (BVDV)7 and bovine respiratory syncytial virus (BRSV). Viral infection of the lungs along with secondary bacterial infection with Histophilus sp. is a common presentation in feedlots and is a major cost to the industry. In this case, the pathogenesis of disease in grassfed cattle was similar to that found in feedlots. In the absence of feedlot management strategies, such as daily use of trained pen riders to identify clinical cases early, deaths occurred before the problem was identified because the livestock were only periodically monitored. Graziers in this region have been advised to monitor their cattle more closely during the change of seasons, when it appears that this problem may emerge.

Humpy back in young sheep near ForbesHumpy back is a locomotor disorder that usually occurs in older sheep. This case involved what the owner described as ‘the best’ young ram lambs on a Merino stud in the Central West region where the condition had not been previously reported.

The owner reported that 30% of a group of 300 ram lambs were ‘stiff-legged’ with a ‘dropped tail set’. A similar syndrome of low prevalence had sporadically occurred previously and was thought to be arthritis from a Chlamydophila pecorum infection.

A private veterinarian and the district veterinarian examined five affected ram lambs. Each animal had a hunched lower

7 Only BVDV type 1 (BVDV-1) is present in Australia. The severe BVDV-2 form in Europe and North America has not been found in Australia.

back with a shortened step in the hindlimbs and became tired after being moved around a small paddock. When pressured, the most severely affected lambs knuckled over in the hindlimbs and ‘dog sat’ before collapsing and lying down upright on their sternums. A badly affected lamb was euthanased. Necropsy showed some mild muscle bruising in the spinal muscles but no other significant lesions.

At the laboratory, blood samples were negative for Chlamydia antibodies. Histopathology revealed spinal cord white matter and nerve roots had mild Wallerian degeneration (a disintegrative process affecting nerve axons). There was mild-to-moderate subacute multifocal necrosis of the lumbar muscles along the spine associated with a minor increase in levels of creatine kinase (from 383 to 1284 µL/L) in all five blood samples (normal < 300). Selenium levels in a liver sample were normal, which excluded white muscle disease.

A plant that has previously been implicated as a possible cause of the disease — quena or wild tomato (Solanum esuriale) — was found in reasonable-sized patches. There was evidence that the quena had been eaten, despite the fact that the sheep were in a lucerne paddock and had ready access to oaten hay and mineral supplements.

The owner had observed that a disproportionate number of the best ram lambs were severely affected. Because the syndrome is exacerbated by activity, it is possible that the bigger-framed and heavier-woolled ram lambs were under greater heat and exertional stress and therefore were the first animals to show signs of the disorder.

One month after the ram lambs had been moved to ‘clean’ paddocks and off the quena, they showed a dramatic improvement.

Photo: Animal Health Australia

11Animal Health Surveillance Quarterly | Volume 20 | Issue 3

During the quarter, the Department of Primary Industry and Fisheries

conducted 120 livestock investigations to rule out emergency diseases and to provide assurance on the distribution and prevalence of notifiable diseases. Field investigations were conducted by government veterinary or biosecurity officers (110) and private veterinary practitioners (10) subsidised by the department. Diagnostic samples of field investigations were processed by Berrimah Veterinary Laboratories.

The number of field investigations by category of livestock is shown in Figure 2.

During the quarter, the state veterinary diagnostic laboratory processed approximately 278 submissions, of which 57% were diagnostic requests for field investigations and the remainder were for health checks for export (1%), animal movements and accreditation programs (13%), targeted surveillance (28%) and regulatory activities (1%).

The department provides a free disease investigation service to livestock owners for diagnosis of notifiable emergency, exotic and endemic diseases, including zoonotic diseases. Subsidies are available to private veterinarians for significant disease investigations in livestock. Berrimah Veterinary Laboratories provide free diagnostic testing for exclusion of notifiable diseases for all disease investigations.

The following case reports are a selection of field investigations, chosen to reflect the range of livestock disease incidents during the quarter.

Northern Territory

Susanne Fitzpatrick, Department of Primary Industries and Fisheries

Ironwood toxicity in heifersMortality was investigated in a consignment of 1000 heifers in the Darwin region. The heifers had been held in yards at the property for 1 week with no illness observed before being moved into a paddock when sudden death was observed and reported in four heifers. Necropsy of one heifer revealed it to be in good condition with the myocardium enlarged and diffuse petechiation. Subacute myocardial degeneration was seen histologically, suggestive of exposure to a cardiotoxin. Several leaves of northern

ironwood (Erythrophleum chlorostachys) were found in the rumen. Northern ironwood leaves contain diterpenoid alkaloids that are highly toxic when ingested by livestock and as few as 2–3 leaves are known to be lethal. The young leaves of new plants are very attractive to hungry and newly introduced grazing stock. Ironwood trees were identified in the paddock after close examination. Transmissible spongiform encephalopathies (TSE) were excluded. The heifers were immediately removed from the paddock and no further losses were reported.

Figure 2 Number of field disease investigations in the Northern Territory, July–September 2015

Northern ironwood (Erythrophleum chlorostachys) is toxic to livestock. Photo: Department of Primary Industry and Fisheries.

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12 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Ionophore toxicosis suspected in buffaloes. Photo: Department of Primary Industry and Fisheries.

Ionophore toxicosis in buffaloesLoss of 30 of 110 heifer buffaloes was reported over a 10-day period on a property in the Katherine region. The animals had been held at the property for a 3-month period with minimal stress. Adequate shade and water sprays were being provided and the buffalo were quiet and in good condition. Chopped Cavalcade hay and pellets had been provided on an ad lib basis in feed troughs, along with jarrah–sorghum baled hay fed from containers in the yards.

Necropsy of two affected animals revealed mucosa of the abomasum and small and large intestines to be severely inflamed, as were the lungs, gastrointestinal tract, spleen and kidneys. However, there were no obvious haemorrhages on the serosal surfaces of these organs. The liver and myocardium were congested. Laboratory testing failed to find evidence of systemic infectious disease. The main histological finding in both animals was moderate-to-severe subacute myocardial degeneration, which likely led to pulmonary congestion and oedema, and generalised vascular congestion in various other tissues. Extensive concurrent myopathy was observed in a single sample of skeletal muscle that had been randomly selected. This finding is highly suggestive of

ionophore toxicosis. Monensin is an ionophore commonly incorporated into cattle supplements. These compounds alter membrane permeability to electrolytes by influencing transmembrane transport. In excess or overdose, any of these ionophore compounds will damage skeletal and cardiac muscle, although there is species variation in susceptibility. Monensin toxicosis has previously been reported in water buffaloes.

On investigation, it was found that the pellets offered were a mixture of various types, including a weaner cattle pellet containing monensin at a rate of 1.5 kg/1000 kg. Management estimated that the weaner pellets had been used for approximately 7 weeks before losses were reported. Buffalo are suspected of having increased susceptibility to the toxic effects of monensin. There were no losses in the approximately 2000 cattle on the same property receiving an identical ration to the buffaloes.

After the monensin-containing feedstuff was withdrawn from the buffalo herd, no further losses occurred. As the surviving animals are likely to have varying degrees of subclinical myocardial degeneration and fibrosis, advice was given to minimise physical stress when handling these animals in the future.

Poxvirus in buffalo calfMultiple skin lesions were noted in a 3-month-old buffalo calf that had been bottle fed since being found orphaned on a remote flood plain. The calf had been taken to a rural property, where there was no other livestock, at a few days of age. The calf was in poor condition and had been suffering from intermittent diarrhoea and anorexia for several weeks. There were multiple round well-demarcated areas of depigmentation over the dorsal head and nose. Some lesions appeared to have a slight scabby outline and others were more pigmented and appeared as if they were resolving.

Haematology and biochemistry of the calf revealed a mild anaemia, normal serum iron and moderate dehydration. The faecal egg count was low. Biopsy of the skin lesions showed a moderate epidermal hypertrophy and hyperplasia with intraepidermal vesicles and pustules. This was grossly and histopathologically consistent with poxvirus infection. Aspergillus niger was cultured from the lesion, although this was likely an environmental contaminant.

It is likely that immunocompromisation due to poor nutritional management contributed to the susceptibility of this calf to poxvirus infection, which may have been transmitted by rodents or wildlife known to be in the area. Nutritional advice on hand-rearing buffalo calves was given but the calf died one week later. There were no reports of zoonotic infection of the handlers.

Marek’s disease in poultryThe management of a smallholder block in Katherine reported recumbency in a number of young roosters. The affected birds also had a dropped wing. Necropsy was unremarkable. Histology revealed a pleomorphic infiltrate of lymphoid cells in various tissues, including peripheral nerves, consistent with one of the avian virus-induced lymphoproliferative disorders. Considering the young age of the affected roosters, a diagnosis of Marek’s disease virus was considered most likely. Avian influenza virus and Newcastle disease virus were excluded via laboratory testing.

13Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Hendra virus infectionHendra virus (HeV) infection was confirmed in one horse on a property in the Atherton Tableland, Far North Queensland, in July.

The property had eight horses in total, three of which were not vaccinated against HeV. One unvaccinated horse showed lethargy and ataxia, which progressed to recumbency within 12 hours. The owner euthanased the horse and a private veterinarian took nasal and rectal swabs the following morning, prior to deep burial. Both swabs returned positive results to PCR testing for HeV.

The property was quarantined and two unvaccinated horses and six in-contact dogs were identified as being at-risk. Blood samples and swabs were collected on day 4 and day 20, counted from the last potential contact with the infected horse. All samples tested negative and the quarantine was ended after one month. One of the unvaccinated horses was an aged animal that has since been euthanased. The other unvaccinated horse has now been fully vaccinated against HeV.

The property had no history of roosting colonies of fruit bats. The paddock layout was such that feeding points were not located under trees. Water was supplied from a dam, which had some sparse surrounding trees. The property did have fruit bats fly over to roosting spots in nearby scrubland. This is the first confirmed case of HeV in Queensland for 2015; the previous confirmed case was in Gladstone in July 2014.

During the quarter, 267 equine submissions for HeV disease investigation were made to Queensland’s Biosecurity Science Laboratory. A further 35 submissions were made for health testing to exclude HeV in clinically well horses before interstate or international movement, movement to stud or veterinary procedures that posed a high risk of disease transmission. Apart from the case described above, all HeV investigations were negative.

HeV infection in horses continues to pose significant work health and safety, public health and biosecurity risks. Equine veterinarians should regularly review their HeV risk management systems to ensure that human and animal health risks are minimised as much as practicable. Vaccination is the single most effective way of reducing the risk of HeV infection in horses. Horse owners are advised to talk to their veterinarians about vaccinating their

horses. Further advice for preventing HeV in horses is available from the Queensland Government8.

Hypogammaglobulinaemia a factor in calf deathsAn ongoing investigation into calf deaths at a beef breeding and rearing property in the Shire of Burdekin, North Queensland, has suggested a multifactorial aetiology for the deaths of more than 30 Brahman calves over a 2-month period.

From an at-risk group of approximately 500 calves, daily checks were finding one or two calves, younger than 1 week old, alone, recumbent and very weak. Affected calves were collected and fostered onto one of a number of dairy cows kept for this purpose. About 50% of these fostered calves died after a brief course of black diarrhoea and fever.

A necropsy was performed on one moribund calf. Inflammatory changes in the lung and small intestine suggested the early stages of sepsis. Serum gamma-glutamyl transferase (GGT) was 25 IU and globulin 20 g/L (normal 30–45 g/L). A serum GGT of less than 250 IU/L in 1–7-day-old calves is suggestive of inadequate colostrum intake. The finding of low globulin supported a diagnosis of failure of passive transfer (inadequate colostrum). Salmonella enterica subsp. enterica serovar Havana was cultured from a jejunal swab. Blood samples and rectal swabs from a further three febrile calves failed to culture any Salmonella spp. but showed very low levels of GGT and globulin.

Many of the breeding cows on the property are very old, some older than 20 years, and many have poor udder conformation or ‘bottle teats’. They are nevertheless in good condition and receiving good quality feed. The age and conformation of cows is thought to be the primary factor contributing to the calves missing their first colostrum feed and subsequently succumbing to opportunistic infection.

The owners are receiving management advice from Department of Agriculture and Fisheries veterinary and extension staff in the care and treatment of this year’s calves and the steps to take to ensure this does not recur. Cows are to be drafted and a controlled breeding program put in place.

8 www.daf.qld.gov.au/animal-industries/animal-health-and-diseases/a-z-list/hendra-virus

Queensland

During the quarter, Queensland’s Biosecurity Science Laboratory

received 1246 terrestrial animal submissions from within the state. Approximately 74% of these were for disease investigations. The remainder came from surveillance programs (10%), regulatory activities (4%) and health checks (12%) for export, movements and accreditation programs.

Biosecurity Queensland provides subsidised laboratory services to the submitter whenever an emergency, exotic, emerging, significant endemic or significant zoonotic disease is a potential diagnosis. During the quarter, Biosecurity Queensland received 939 accessions from clinically ill animals for disease investigation. Each accession may involve samples relating to one or multiple animals.

Cattle accessions (457) accounted for 49% of disease investigation accessions, reflecting the size and economic significance of Queensland’s cattle industry. Other species submitted were horses (273), wildlife (25 bats, 8 wild birds, 1 Tasmanian devil, 4 macropods), pigs (34), bees (35), aquatic animals (19), commercial birds (23), sheep (24), goats (20), camelids (8), and 10 others (4 dogs, 3 donkeys, 1 deer, 2 caged birds).

Greg Williamson, Queensland Department of Agriculture, Fisheries and Forestry

Photo: Cathy Kovarik

14 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

South Australia

Biosecurity SA (BSA) subsidises disease investigations when an

emergency disease is considered possible. During the quarter, BSA subsidised 199 clinical disease submissions through the state veterinary laboratory. Most of these submissions were investigations by private veterinary practitioners (76%), with the remainder by BSA staff.

During the quarter, most of the subsidised clinical disease events recorded through the state veterinary laboratory involved sheep (70) and cattle (70); others included pigs (30), domestic birds, including poultry (10), goats (2) and alpacas (2) (Figure 3).

Disease events occurring in wildlife are recorded in a national database managed by the Australian Wildlife Health Network

Celia Dickason, Department of Primary Industries and Regions

and are reported separately. No exotic or emergency animal diseases were diagnosed in South Australia during the quarter.

The producer was advised to treat remaining cattle with an appropriate antimicrobial and to supplement their nutrition with good quality hay. He was also advised to monitor animals closely for signs of illness and to consider implementing a vaccination program for respiratory diseases. There were no further reports of disease.

Lead poisoning in yearling heifersIn late July 2015, a producer on the north-western Eyre Peninsula moved a group of 31 yearling heifers into a new paddock. They were then observed rummaging in an open dump site in the paddock. A week later, one heifer was found dead and two others were observed with neurological symptoms, including aimless wandering, walking into fallen trees, head pressing, leg buckling, head shaking and blindness. One of these animals died later that day.

Necropsy and testing revealed markedly elevated lead levels measured in the kidney (381.00 µmol/kg wet weight; reference range < 2.00). Sections of the brain examined did not show evidence of laminar necrosis, which is not always evident in acute cases of lead toxicity. Two of six remaining animals sampled were found to have raised blood lead levels of 4.15 µmol/L and 1.15 µmol/L, respectively (normal 0.05–0.97 µmol/L). A diagnosis of acute lead toxicity was considered the cause of death in this case, presumably caused by access to the dump site.

Cattle were moved out of the paddock and the dump has since been buried. Repeat blood sampling of all remaining animals in early September showed only two animals with elevated lead levels. Slaughter restrictions have been placed on these animals and an instruction order issued to the producer.

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Figure 3 Disease investigations subsidised by Biosecurity South Australia, July–September 2015

July August September

Photo: Dollar Photo Club

Pasteurellosis causing sudden death in cattleA producer in the Upper South East region of South Australia reported illness and death in his herd of 500 Angus cows. Over the previous 2 days, four animals had died and a further two were recumbent and frothing at the mouth. The herd grazed together and cows were rotated between pastures of dryland lucerne (Medicago sativa) and capeweed (Arctotheca calendula).

On investigation, available pasture was obviously of poor quality and was predominantly capeweed on light sandy soils. Two affected animals each had a 4-month-old unaffected calf at foot. Anthrax was ruled out with a negative penside anthrax test. Necropsy revealed poor body condition, little ruminal or digestive tract contents and severe bronchopneumonia with pleurisy and fibrinous pleural effusion. Histopathology confirmed the morphological diagnosis of severe suppurative fibrinous bronchopneumonia and acute periacinar hepatic necrosis. Lung culture revealed a heavy growth of Pasteurella spp.

Outbreaks of pasteurellosis are often associated with husbandry procedures where animals are grouped together and investigators often assume an underlying viral infection, such as a herpesvirus, predisposing to tracheitis, tracheobronchitis and establishment of upper respiratory tract flora in the lungs.

15Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Mesenteric torsion in sudden lamb deathsIn early July 2015, sudden death in newborn lambs was investigated on a Kangaroo Island property. Nine lambs had died suddenly out of 76 born from two ewe groups at the time of investigation. These deaths occurred within the first 3 weeks of lambing.

One group of lambs was from 220 Border Leicester–Merino cross ewes joined to a terminal sire (Dorset or White Suffolk) and the other was from 270 Merino ewes joined to a Border Leicester ram.

Two necropsies found abomasum full of milk or curds and a twisted mesentery with engorged intestinal vasculature and erythematous small intestinal serosa. Rectal serosal vessels were also engorged.

Histopathology revealed moderate diffuse mesenteric and serosal lamina proprial congestion in the small intestine with loss of villi components. This was consistent with the mesenteric torsion observed grossly.

In some well-fed animals, twisting of the mesentery is thought to be related to

bacterial overgrowth, possibly due to Clostridium spp. This was an unusual case as no cause could be found on examination of tissues submitted and literature searches and discussion with other veterinarians failed to uncover any similar cases in lambs this age.

Severe footrot in Dorper lambsDuring July 2015, a sheep producer in the south-east reported severe ongoing lameness in his Dorper flock of 900 ewes with lambs. At the time of investigation, the 4–6-week old lambs were displaying obvious lameness with some knuckling over when attempting to walk. The ewes were lame but their symptoms were not as severe as the lambs.

Foot inspection for footrot is performed using a standard foot scoring system based on the presence of inflammation and degree of ovine interdigital dermatitis. Scores of 0–2 have some interdigital hair loss, as well as sweating and slight ridging between the claws. Scores of 3–5 occur when there is a break at the junction of the skin and hoof, from where infection spreads under the horn tissue, so that the

Photo: iStock

wall of the hoof becomes separated and the sole underrun. There is also a characteristic foul-smelling discharge. In chronic cases, the hoof walls and toes become overgrown and misshapen.

The flock in this case was inspected and 53% were observed to have footrot lesions of scores 3–5. Underrun soles were widespread and there was evidence of separation of the soft and hard horns on the outer hoof walls. Swabs were positive for Dichelobacter nodosus and positive on the gelatin gel thermostability test for bacterial serine proteases.

Footrot is caused by D. nodosus. The bacteria can live in the feet of infected sheep for years and can survive in the environment for up to 7 days. It is introduced to a clean flock by infected sheep.

The producer will commence a footrot eradication program. To help reduce the severity of lameness in the flock, animals will undergo foot bathing in a 10% zinc sulfate solution for 5–10 minutes. The frequency of this will depend on the amount of lameness observed.

16 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

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Figure 4 Number of field disease investigations in Tasmania, July–September 2015120

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During the quarter, 22 field investigations were conducted by

government veterinarians or biosecurity officers and 388 by private veterinary practitioners. Diagnostic samples of field investigations were processed by the state veterinary diagnostic laboratory, as was exclusion testing for bovine tuberculosis on a sample submitted from a Tasmanian abattoir. The number of field investigations by category of livestock is shown in Figure 4.

Most animal disease investigations were undertaken by private veterinary practitioners. Private practitioners often liaise with veterinary officers from the Department of Primary Industries, Parks,

Sue Martin, Department of Primary Industries, Parks, Water and Environment

Water and Environment (DPIPWE) in the event of unusual disease events. Private veterinarians are eligible for funding under the National Significant Disease Investigation (NSDI) Program for disease investigations where presenting signs maybe consistent with an exotic, emergency or emerging disease if undertaken in consultation with DPIPWE senior veterinary officers and relevant samples are submitted to the state veterinary laboratory. These investigations receive highest priority.

During the quarter, the state veterinary diagnostic laboratory processed approximately 410 submissions, of which 57.2% were diagnostic requests for field investigations and the remainder were for health checks for export (0.2%), animal movements and accreditation programs (5.6%), targeted surveillance (29.7%) and regulatory activities (7.3%).

Gastrointestinal helminthosis was the main cause of ill-thrift and diarrhoea in sheep, goats and laboratory submissions. Seasonal submissions of ruminant foetuses for abortion and stillbirth investigations commenced in July 2015.

Unusual climatic conditions during the quarter, including below-average temperatures, below-average rainfall and several widespread snowfalls, had an adverse effect of livestock health.

The following case reports are a selection of field investigations chosen to reflect the range of livestock disease incidents during the quarter.

Campylobacter fetus in ewesCampylobacter fetus was confirmed in two investigations of ovine abortion.

The first event involved 16 ewes from a group of 2000 that aborted approximately 4 weeks prior to their expected lambing date. The flock had been brought in from another property about 1 month prior to the abortions and the ewes were in light- to-medium body condition. At the time of the abortions, the ewe flock was intensively housed and on supplementary feed.

Four aborted foetuses were submitted to the state Animal Health Laboratory. No gross abnormalities were noted but all lambs were found to have acute, diffuse suppurative pneumonia and two of the four lambs had multifocal suppurative encephalitis. Campylobacter spp. was cultured in tissues from all lambs and Campylobacter fetus was confirmed by PCR (suspect C. fetus subsp. fetus). Toxoplasmosis indirect fluorescent antibody test (IFAT), Leptospira pomona and L. hardjo microscopic agglutination tests (MATs) and BVDV antigen capture enzyme-linked immunosorbent assay (ELISA) tests were negative for all four foetuses.

As the flock was intensively housed, it was not possible to initiate a management strategy to disperse the group to lower the transmission rate. However, the abortion storm tapered off quickly and the peri-parturition lamb mortality rate did not increase significantly. While exact figures will not be known until pre-lamb scanning records can be compared to the lamb marking percentage, overall losses were around 5%.

The second ovine abortion event occurred in a flock of around 1100 mixed-aged ewes grazing on pasture. About six lamb foetuses were aborted over a 3-day period approximately 10 days prior to the expected start of lambing.

Four aborted foetuses were submitted to the state Animal Health Laboratory. Multiorgan inflammation, including placentitis, bronchopneumonia, adrenalitis, hepatitis and meningioencephalitis, was found in all four lambs. Campylobacter spp. was cultured from these samples and Camplobacter fetus was confirmed by PCR (suspect C. fetus subsp. fetus).

The stocking rate of the pasture was lowered by dispersing the flock to reduce the transmission of the bacteria. The occurrence of abortions quickly tapered off with no significant increase in peri-parturition lamb mortality rates.

July August September

17Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Actinobacillosis in dairy calvesCutaneous actinobacillosis was confirmed in a group of yearling calves in the north-west of the state. Seven yearling dairy calves from a group of 170 were noted to have multilobulated subcutaneous nodules around the mouth and along the jaw. A small amount of pus was evident on needle aspiration. Surgical biopsy was performed and material submitted for histology and culture.

Histologically, there was a multifocal granulomatous cellulitis with club rays around colonies of gram negative coccobacilli, typical of actinobacillosis. Actinobacillus lignerisii was isolated on culture.

One of the calves died and necropsy revealed extensive nodules on the soft palate, as well as nodules throughout the cheek muscles and lungs. All remaining calves were treated with antibiotics and sodium iodide and responded well to treatment.

Actinobacillosis is usually associated with classical wooden tongue but can occur in other forms, such as lymphadenitis and multifocal cellulitis (skin nodules). Cutaneous lesions usually occur secondary to abrasions, such as those caused by rough coarse feed, grass seeds and awns. In this case, the disease presented in calves that were grazing good quality pasture but prior to this they had been grazing a paddock heavily infested with blackberries.

Photo: Dollar Photo Club

18 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Num

ber o

f dis

ease

inve

stig

atio

ns

Cattle Sheep Avian Goat Horse Pig Camelid CervineType of animal

140

120

100

80

60

40

20

0

Nonspecific clinical patterns were most commonly reported, followed by signs associated with the gastrointestinal tract, central nervous system and reproductive system. Gastrointestinal diseases were the most commonly diagnosed diseases in cattle. Infectious laryngotracheitis in poultry continued to be a problem for producers in the Gippsland region this quarter, with 27 reports, mostly based on clinical signs. Following on from the previous quarter, another 19 cases of strangles in horses were reported, of which 13 were confirmed by laboratory testing. Cases of clinical disease where no definitive disease agent was identified were reviewed in context, and exotic or emergency diseases were excluded where appropriate. Test results from exotic or emergency animal disease exclusion testing are routinely recorded in the table of suspect emergency animal diseases (Table 17).

Strangles in horsesSince May 2015, 24 strangles incidents have been reported in Victoria, of which 17 were confirmed by laboratory testing. Strangles is an infectious disease of horses, ponies and donkeys caused by Streptococcus equi subsp. equi. It is a notifiable disease in Victoria under the Livestock Disease Control Act 1994 and must be reported within 7 days to a departmental veterinary or animal health officer. No regulatory action is routinely taken and properties are not placed under quarantine. The requirement to notify ensures that, particularly in cases where multiple horses are affected and there has not previously been laboratory confirmation of strangles, the possibility of the presence of exotic diseases (e.g. equine influenza) can be ruled out in a timely manner.

Most of the properties involved were located on the outskirts of Melbourne; six were located in the north of the state. In total, 48 horses were affected, including one death. Signs most commonly reported were nasal discharge, skin abscesses, fever and lymphadenopathy.

As a result of the increased number of cases, departmental veterinary officers routinely contacted the notifying veterinarian (and/or property owner) to ensure adequacy of biosecurity and management of cases. Relevant equine organisations were contacted and advised of developments.

Four reported cases (two laboratory confirmed and two based on clinical signs) were linked to the purchase of horses through a saleyard. Departmental staff determined that these horses were likely to have been asymptomatic or recovering at the time of purchase from the saleyard. Strangles is highly contagious so implementation of biosecurity measures

Victoria

Karen Moore, Department of Economic Development, Jobs, Transport and Resources

During the quarter, the Victorian Department of Economic

Development, Jobs, Transport and Resources recorded 616 clinical disease investigations. These included department-subsidised investigations undertaken by private veterinary practitioners, investigations undertaken by departmental staff (including those for targeted surveillance programs) and reports of notifiable diseases received from private veterinarians and laboratories. Of the 606 completed investigations, 85% used laboratory testing to establish the final diagnosis.

Most of the clinical disease investigations recorded during the quarter involved cattle (Figure 5).

Figure 5 Clinical disease investigations recorded in Victoria, July–September 2015

July August September

Photo: Animal Health Australia

19Animal Health Surveillance Quarterly | Volume 20 | Issue 3

was imperative to control the spread of the disease from this location. On the advice of departmental staff, the saleyard manager revised sale protocols and made printed information available to the public. Departmental staff also contacted owners of horses purchased from the saleyard and provided them with information about disease management and prevention.

Hendra virus exclusion in Queensland horseA thoroughbred broodmare died overnight in late September 2015 while being transported from Caloundra, Queensland, to Peterborough, Victoria, for breeding. The mare was reported to have shown no signs of illness or stress and had not struggled or suffered any physical trauma. She was travelling in a small specialised horse transporter that held five horses. Over the course of the journey, a total of six other horses had shared the truck with the case horse. The other horses were visually healthy and had been delivered to several properties on the way to and through Victoria. The mare was loose in the rear of the truck when parked overnight, with the driver sleeping in the cab. There was a video and audio monitor that did not indicate anything of concern to the experienced driver. The mare, who had not been vaccinated against Hendra virus (HeV), was found dead in the morning.

Without any other signs, sudden death alone can be caused by the nervous form of HeV infection, which prompted exclusion testing for HeV infection in this case.

Departmental animal health staff donned appropriate personal protective equipment and collected samples from the carcase for testing at the CSIRO Australian Animal Health Laboratory. Negative PCR results for HeV infection were reported within 5 hours of receipt. An anthrax immunochromatographic test (ICT) was conducted and found to be negative.

The presumed cause of death of the mare was an acute vascular accident.

Malignant catarrhal fever in Angus steers Malignant catarrhal fever (MCF) led to the death of one 12-month-old Angus steer and euthanasia of another from a group of 300 located on a property near Towong, north-east Victoria, in September 2015.

Prior to death, the affected steers were lethargic, dehydrated and pyrexic, and had bilateral corneal opacity, purulent ocular discharges, crusty nasal discharges, melaena and nystagmus. Histopathology showed bilateral keratitis and uveitis, pharyngeal ulceration, necrotising abomasitis and ulcerative ileitis with severe vasculitis. The alimentary tract, ocular and vascular lesions were typical of MCF. PCR testing of ethylenediamine tetraacetic acid (EDTA) blood for ovine herpesvirus 2 (OvHV-2), the primary cause of MCF in Australia, was negative but histological lesions were sufficiently characteristic to be confident of a diagnosis of this disease. Spleen and lymph node, the preferred specimens for MCF PCR testing in necropsied animals, were unavailable for testing. The steers’ paddock was immediately adjacent to a paddock of lambing ewes, which were the likely source of the outbreak. The producer was advised to separate the remaining cattle from the neighbouring sheep.

Anthrax exclusion in a heifer In August 2015, a Hereford heifer from a property located near Bonnie Doon, north-eastern Victoria, was found dead an hour after it had been seen standing. The heifer had diarrhoea prior to death and had been found recumbent 2 days previously before being walked home. The heifer remained inappetant after its return. On physical examination, the private practitioner found unclotted blood seeping from the mouth, eye and anus. As anthrax was suspected, the practitioner contacted the department’s district animal health staff.

A cow-side anthrax ICT on jugular blood was negative and the blood seepage appeared to be due to crow predation on exposed mucous membranes. Necropsy revealed a generalised septic peritonitis with extensive fibrinous adhesions and more than 2 L of greenish exudative fluid (similar to rumen fluid). All abdominal organs appeared grossly normal except for the fibrinous adhesions on their surfaces and a small demarcated necrotic area on the surface of the rumen. There were petechiae on the heart and some pleural fluid; otherwise no other significant lesions were found in the thoracic cavity.

Together with the above findings, the presence of a rusting fencing wire found in a small abscess in the inguinal region supports the diagnosis of chronic traumatic reticuloperitonitis (hardware disease) which subsequently led to septicaemia, disseminated intravascular coagulopathy and death.

Monophasic Salmonella Typhimurium (1,4,5,12:i) in calvesSalmonellosis caused the death of 20 Friesian-cross calves aged 0–3 weeks and sickness in the remaining 15 on a property near Tallangatta, north-east Victoria, in August 2015. Affected calves had diarrhoea and were lethargic, anorexic and pyrexic.

Necropsy of two calves revealed severe acute, diffuse haemorrhagic enteritis with gas distension. Histological examination showed severe necrotising enterocolitis, multifocal hepatitis and interstitial pneumonia consistent with salmonellosis. Salmonella sp. was cultured from the faeces of four calves and from the lung and spleen of the two necropsied calves. The isolates were identified as Salmonella enterica serotype Typhimurium 1,4,5,12:i, which was resistant to ampicillin, amoxicillin, tetracycline, streptomycin and sulfathiazole.

Salmonella 1,4,5,12:i is antigenically similar to Salmonella Typhimurium but is monophasic in that it lacks the second-phase flagella. Multiple antibiotic resistance is commonly reported in this organism. The producer was advised to use good hygiene by washing hands, using gloves, disinfecting equipment, handling healthy calves first and being mindful of the early clinical signs of disease so as to protect both themselves and their unaffected calves.

Photo: iStock

20 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Foot-and-mouth disease excluded in lame lambsIn June, a sheep and cropping farmer on a property just south of Lake Mulwala, north-east Victoria, reported a severe outbreak of scabby mouth (contagious ecthyma; orf in humans) in lambs. All the weaned crossbred lambs were affected with typical lip and nares lesions; a large percentage had lesions around the coronets. Lesions began developing after the lambs had been weaned onto a paddock of predominantly native grasses. As the paddock had received considerable inundation, moving them would have proved difficult. It was decided not to move the lambs as the scabs lifted and fell off. Three months later, about 60 from the group of 500 lambs, aged 11 months, were still showing signs of lameness in one or two feet. The lamb flock was slowly moved from the paddock to the home property one day before the veterinarian’s visit.

An assessment of the lamb flock found approximately 100 lambs had pink scurfy depilated skin around their lips and nares with about 50% of these with similar pink depilated skin around the coronets. Lameness with weight bearing was observed but not in all feet. Examination of the hooves showed a separation of the hoof horn; those with extended toes had pockets of mud and faeces along the lateral wall. A large number were resolving with the toes cracked off and the hoof

structure returning to normal. No interdigital inflammation was present. EDTA and plain blood samples were collected and submitted to the state veterinary diagnostic laboratory (AgriBio) and CSIRO Australian Animal Health Laboratory for exclusion testing. The negative serology and molecular diagnostics (TaqMan assay) for vesicular stomatitis and bluetongue viruses and for foot-and-mouth disease virus serotypes supported the clinical diagnosis of shelly toe as a sequel to scabby mouth. As the lameness had delayed the sale of the lambs, the producer was advised to put the lambs onto a firmer paddock to allow the hooves to resolve and wear, then sell when they were fit to load on a transport vehicle.

Phalaris staggers leading to sheep deaths Six out of 600 Merino-cross lambs, aged 4 months, near Violet Town, north-east Victoria, exhibited neurological signs after mustering for weaning in September 2015. The lambs had severe, prolonged tremors if agitated, with one walking on its knees. Since birth, they had been grazing on mixed species pasture with about 50% Phalaris spp. content. No ewes were affected.

Five days after onset of signs, examination of two lambs, one of which had diarrhoea, revealed rectal temperatures above 41°C, elevated respiratory and heart rates and normal lung sounds. They had severe

hyperaesthesia, with tremors continuing for 1 minute after stimulus. No menace reflex was observed, although they didn’t appear blind in the yards, and there was no startle reaction to sudden loud noises. Necropsies revealed slightly pale muscles and small patches of consolidation in the lungs. The state veterinary diagnostic laboratory (AgriBio) reported that grossly, both formalin fixed brains had marked bilateral slate green discolouration of grey matter nuclei in the brain stem and midbrain, particularly in the lateral geniculate nucleus, indicative of phalaris staggers.

Haematology was normal with glutathione peroxidase within the normal range, indicating no selenium deficiency. Biochemistry revealed high creatinine-kinase, indicating acute muscle damage, and mildly elevated liver enzymes. Faecal egg counts undertaken on the two scouring lambs found 960 and 1680 strongyle eggs per gram (epg) and 600 and 8700 coccidia oocysts per gram, respectively.

Histopathology of the brains revealed accumulation of green–brown granular pigment in the cytoplasm of neurons within grey matter of the brain stem and midbrain. Wallerian degeneration was evident in the distal brain stem at the transition to the spinal cord, most prominent in the lateral corticospinal tract. The abomasa and jejuna showed evidence of parasite damage.

The brain histopathology is characteristic of phalaris staggers resulting from repeated or chronic ingestion of methylated tryptamine alkaloids present in Phalaris aquatica. Neurological signs that do not resolve when animals are removed from the pasture, and walking on the knees, are indicative of phalaris staggers. The staggers syndrome is reported to be caused by chronic ingestion of the alkaloids and appears to be long term, with no treatment. The producer was advised that prevention included barring hungry sheep from phalaris-dominant pasture and the use of cobalt as oral bullets (3 years protection), top dressing pasture or weekly drenching of individual sheep with a cobalt solution. Two other sudden death syndromes related to ingestion of Phalaris spp. appear to be caused by other unknown toxic mechanisms.

It is unknown whether the high worm burdens exacerbated the effect of the phalaris alkaloids on the brain in these six individuals relative to the rest of the flock. Two lambs were euthanased but the producer reported that another two lambs recovered within 2 weeks.

Photo: Dollar Photo Club

21Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Western Australia

Jamie Finkelstein, Department of Agriculture and Food WA

During the quarter, the Department of Agriculture and Food WA (DAFWA)

Animal Health Laboratories received 695 laboratory submissions, of which 44% were for disease investigations and the remainder were from accreditation programs (14%), targeted surveillance programs (13%), single disease herd tests (13%), parasitology (12%), export testing (4%) and regulatory activities (1%).

Brucella abortus excluded in bovine abortionsDAFWA liaises with livestock industry stakeholders, including farmers, private veterinarians and livestock agents, on conducting surveillance for reportable diseases to support market access for livestock and livestock products. This has included considering brucellosis when presented with aborting livestock. Two abortion cases were investigated in July 2015 where Brucella abortus was excluded.

In the first incident, a private veterinarian investigated a report of aborted and stillborn calves in an Angus herd in the South West Agricultural region. Out of a herd of 16 heifers aged 2–3 years, five had stillborn calves and four aborted; only seven gave birth to live calves.

During the on-farm investigation, blood samples were taken from the 16 animals to test for causes of stillbirth and abortion. Samples were negative for Leptospira and Campylobacter spp. and exclusion testing was negative for B. abortus in all animals.

Two affected animals had positive results for Neospora antibodies and low selenium levels were detected in 15 animals. Serological testing revealed bovine pestivirus (BVDV) was circulating in the unvaccinated herd.

In the second incident, a private veterinarian investigated a report of abortion in a 2-year-old Friesian heifer from a South West Agricultural region producer. During the on-farm investigation, the veterinarian found that the heifer had retained foetal membranes. Blood samples from the heifer, foetal membranes and fresh and fixed tissues from the aborted calf were submitted to the DAFWA Animal Health Laboratories.

Histopathology revealed necrotising enteritis, fibrinosuppurative placentitis and meningitis, all with bacilli present. Bacterial culture of the lungs, liver and stomach contents of the foetus returned a pure growth of Listeria monocytogenes. The histological changes noted were typical of listeriosis in a near-term foetus. Samples were confirmed negative for B. abortus, Neospora sp. and BVDV.

These cases show the importance of considering reportable diseases to remain confident of Australia’s freedom from diseases, such as B. abortus which is important from a trade, animal and public health perspective.

Lead investigation in sudden cattle deathsA case of sudden death in 3-month-old Friesian calves on a South West Agricultural region property was investigated by a private veterinarian in July 2015.

The owner had reported that six calves were found dead and one was collapsed and moribund. Clinical signs of the affected calf included blindness, lethargy, circling, anorexia and slobbering. During the course of the on-farm investigation, the private veterinarian located an old battery that had been chewed in the paddock with the calves.

Necropsy and histopathology revealed congestion and haemorrhage in the heart muscle, congestion and oedema in the lungs and congestion in the medulla of the kidneys. Blood samples revealed elevated lead levels consistent with a diagnosis of lead toxicosis. No other significant changes were noted.

Continued on page 22

Photo: Dollar Photo Club

22 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Under the Western Australian Biosecurity and Animal Management Act 2007, livestock known or suspected to have lead residues are managed by DAFWA in coordination with the property owner, to manage animal health and safeguard public health by preventing livestock with residues from entering the food supply chain.

DAFWA provided management advice to the owner on practices to ensure livestock do not have access to lead sources, such as batteries, machinery and painted sheds. Extension material for producers and veterinarians has been developed to raise awareness of lead poisoning and lead residues in livestock.

Neurological signs in a Dorper sheep In August 2015, a DAFWA field veterinary officer investigated a report from a Central Agricultural region producer of a 2-year-old Dorper ewe showing neurological signs.

Clinical investigation revealed the animal had foreleg knuckling and an uncoordinated gait but mentation appeared normal. Necropsy revealed a

hypervascular and inflamed brain and increased fluid around the brain. A full set of samples was taken for histopathology examination, including brain for TSE exclusion testing.

Histopathology showed muscle tissue damage severe enough to explain the knuckling with no other changes noted. Biochemistry showed low vitamin E levels and borderline selenium levels. Given the absence of other findings and with no history of access to toxic plants, nutritional myopathy was diagnosed.

Histological examination ruled out TSE, supporting Australia’s TSE Freedom Assurance Program that involves investigating sheep and cattle of an appropriate age with clinically consistent signs.

Contagious agalactia excluded in ewe mastitisA DAFWA field veterinary officer investigated a report in September 2015 from a South West Agricultural region producer of the sudden death of two Wiltshire sheep from a flock of 100 animals.

In the hours preceding death, one of the animals had been observed to be lethargic with nasal discharge. The ewe was lactating and had a 3-week-old lamb. The ewe had been in good condition and was being fed pellets, hay and was on good pasture.

Necropsy revealed discolouration of the udder and congestion of the lungs. Histopathological examination revealed marked diffuse congestion of the udder and presence of degenerate neutrophils with no other significant findings. Bacteriology supported a diagnosis of bacterial mastitis, with bacterial culture revealing a heavy pure growth of Staphylococcus aureus.

Contagious agalactia was excluded as part of the diagnostic investigation. Excluding reportable diseases, such as contagious agalactia, and reaching a definitive endemic disease diagnosis as part of a routine diagnostic process has the dual purpose of assisting the affected producer to manage the disease event while supporting the wider livestock sector by demonstrating freedom from reportable diseases.

Photo: Dollar Photo Club

23Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Quarterly statistics

Endemic disease monitoring

Johne’s diseaseIn Australia, Johne’s disease occurs primarily in dairy cattle and sheep, and to a lesser extent in beef cattle, goats, deer and camelids. Infection with sheep strains occurs to varying extents across the sheep-producing regions of southern Australia but has not been detected in Queensland. Cattle strains are endemic in south-eastern Australia but surveillance programs have not identified infection to be endemic in Queensland, Western Australia or the Northern Territory, and active measures are taken to stamp out any incursions. Table 3 shows the number of herds and flocks known to be infected. The reporting of sheep herds infected with Johne’s disease has been replaced with the annual reporting of area prevalence estimates for ovine Johne’s disease in Animal Health Surveillance Quarterly.

Table 3 Herds known to be infected with Johne’s disease, at 30 September 2015

State Alpaca Cattle Deer Goat Total

NSW 0 124 2 3 129

NT 0 0 0 0 0

Qld 0 6 0 1 7

SA 0 55 0 2 57

Tas 0 39 0 4 43

Vic 0 918a 3 13 934

WA 0 0 0 0 0

Aus 0 1 142 5 23 1 170

a Includes herds participating in state test and control programs.

New approaches based on risk assessment and management have been developed to control Johne’s disease. Market assurance programs (MAPs) are in operation for cattle, sheep, goats and alpacas; the numbers of herds or flocks that have reached a status of Monitored Negative 1 or higher are shown in Table 4.

For status definition, see the current species MAP manual, available at www.animalhealthaustralia.com.au/maps. Lists of cattle, goat and alpaca herds and sheep flocks assessed in the MAPs are available on the website. Herd or flock testing is undertaken by a MAP-approved veterinarian. Information about components of the National Johne’s Disease Project can be obtained from state coordinators and Animal Health Australia’s Johne’s disease coordinator, Rob Barwell (02 6203 3947).

Table 4 Herds or flocksa with a market assurance program status of at least Monitored Negative 1, 1 April – 30 September 2015

Quarter Alpaca Cattle Goat Sheep Total

Apr–Jun 2015 25 377 23 388 813

Jul–Sep 2015

NSW 10 149 11 157 327

Qld 0 0 2 0 2

SA 7 114 7 153 281

Tas 0 38 0 13 51

Vic 2 63 1 54 120

WA 0 0 0 4 4

Aus 19 364 21 381 785

a There are no herds or flocks in Northern Territory in the MAPs. Herds or flocks in Free or Protected zones have an equivalent status of Monitored Negative 1 or better because of the zone status.

Ovine contagious epididymitisContagious epididymitis, caused by Brucella ovis, is present in commercial flocks at a low level that varies around the country. Voluntary accreditation programs (usually in stud flocks) for ovine contagious epididymitis freedom operate in all states. Table 5 shows the number of accredited flocks at the end of the quarter.

Table 5 Ovine contagious epididymitis accredited-free flocks, 1 July 2014 – 30 September 2015

StateJul–Sep

2014Oct–Dec

2014Jan–Mar

2015Apr–Jun

2015Jul–Sep

2015

NSW 827 865 865 865 858

Qld 81 81 80 77 77

SA 522 522 522 530 530

Tas 75 81 68 68 59

Vic 496 496 504 496 489

WA 196 195 195 194 194

Aus 2 197 2 240 2 234 2 230 2 207

24 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Laboratory testing

Serological testingTable 6 summarises the results of serological testing for two equine viruses on samples submitted to state and territory animal health laboratories during the quarter. Positive serological test results are not an indication of the presence of clinical disease.

Table 6 Results of serological testing for two equine viruses, 1 July 2014 – 30 September 2015

No. of tests (equine

infectious anaemia)

Positive(equine

infectious anaemia)

No. of tests(equine viral

arteritis)

Positive(equine viral

arteritis)

Jul–Sep 2014 583 0 420 14

Oct–Dec 2014 1 242 0 664 4

Jan–Mar 2015 707 0 897 6

Apr–Jun 2015 463 0 639 4

Jul–Sep 2015

NSW 295 0 341 0

NT 0 0 0 0

Qld 36 0 1 0

SA 0 0 0 0

Tas 0 0 0 0

Vic 250 0 176 0

WA 1 0 1 0

Aus 582 0 519 0

Table 7 summarises the results of laboratory testing for equine herpesvirus 1 on samples submitted to state and territory animal health laboratories during the quarter.

Table 7 Results of testing for equine herpesvirus 1, at 30 September 2015

Syndrome Negative Positive Total

Abortion 76 0 76

Neurological 19 0 19

Other 14 0 14

Total 109 0 109

Table 8 summarises the results of serological testing for three arboviruses on samples submitted to state and territory animal health laboratories during the quarter. Positive serological test results are not an indication of the presence of clinical disease. The distribution of these viruses is monitored by the National Arborvirus Monitoring Program (NAMP)9. Figures reported reflect tests completed at the time of reporting, therefore tests completed may increase in future reporting periods.

Table 8 Results of serological testing for three arboviruses, 1 July 2014 – 30 September 2015*

QuarterNo. of tests (Akabane)

Positive (Akabane)

No. of tests (BEF)

Positive (BEF)

No. of tests (BTV)

Positive (BTV)

Jul–Sep 2014 444 30 513 14 852 42

Oct–Dec 2014 182 5 479 31 724 42

Jan–Mar 2015 257 11 598 46 1 336 37

Apr–Jun 2014 753 31 752 41 1 565 41

Jul–Sep 2015 454 22 576 33 882 37

* Data project revised following Vol 20 Iss 2 to include only data of the NAMP

BEF = bovine ephemeral fever virus; BTV = bluetongue virus

9 http://namp.animalhealthaustralia.com.au

25Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Surveillance activities

Bovine brucellosisAustralia declared freedom from bovine brucellosis (caused by Brucella abortus) in 198910. Surveillance is maintained through abortion investigations and additional testing of cattle for export or other reasons. Table 9 shows 297 bovine abortion investigations and 283 investigations for other reasons were performed during the quarter; all were negative for bovine brucellosis.

Table 9 Bovine brucellosis testing, 1 July 2014 – 30 September 2015

QuarterNo. of tests (abortion)

Positive (abortion)

No. of tests (other reasons)a

Positive (other reasons)

Jul–Sep 2014 152 0 319 0

Oct–Dec 2014 35 0 980 0

Jan–Mar 2015 133 0 1 530 0

Apr–Jun 2015 114 0 1 513 0

Jul–Sep 2015

NSW 31 0 227 0

NT 0 0 0 0

Qld 22 0 41 0

SA 25 0 0 0

Tas 19 0 0 0

Vic 39 0 15 0

WA 161 0 0 0

Aus 297 0 283 0

a A proportion of this testing information is derived from pre-export testing of cattle destined for live export markets where the importing country requires testing. The total number of tests each quarter may therefore vary, depending on total cattle exports to particular markets.

10 www.agriculture.gov.au/SiteCollectionDocuments/animal-plant/animal-health/pet-food-safety/brucella-abortus-colour.doc

26 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

National Transmissible Spongiform Encephalopathies Surveillance ProgramThe National Transmissible Spongiform Encephalopathies Surveillance Program (NTSESP) is an integrated national program jointly funded by industry and government to demonstrate Australia’s ongoing freedom from bovine spongiform encephalopathy (BSE) and classical scrapie, and to provide early detection of these diseases should they occur. The program, based on the World Organisation for Animal Health (OIE) Terrestrial Animal Health Code11, involves testing of samples from cattle and sheep with clinical signs consistent with BSE or scrapie respectively, as well as from fallen and casualty slaughter cattle. Points are assigned to cattle samples according to the animal’s age and subpopulation category (i.e. the likelihood of detecting BSE). Australia’s target is to achieve a minimum of 150 000 points over a rolling 7-year period. Table 10 shows the number of animals sampled for BSE and scrapie and the points tally for cattle in the NTSESP12 during the past 12 months. All samples tested were negative.

Table 10 Samples tested for transmissible spongiform encephalopathies (TSEs), 1 October 2014 – 30 September 2015

State

No. examined

(cattle)Points (cattle)

Positive (cattle)

No. examined

(sheep)Positive (sheep)

NSW 146 51 864.9 0 173 0

NT 32 2 583.0 0 0 0

Qld 194 67 089.0 0 27 0

SA 28 14 441.4 0 53 0

Tas 30 7 500.0 0 18 0

Vic 108 39 217.3 0 145 0

WA 24 11 935.7 0 121 0

Aus 562 194 631.3 0 537 0

11 World Organisation for Animal Health (2014). Bovine spongiform encephalopathy, In: Terrestrial Animal Health Code, OIE, Paris, www.oie.int/index.php?id=169&L=0&htmfile=chapitre_bse.htm

12 Additional information about the NTSESP is available at www.animalhealthaustralia.com.au/programs/biosecurity/tse-freedom-assurance-program

Avian influenzaAustralia is currently free from highly pathogenic avian influenza. A number of low pathogenic subtypes of avian influenza have been found in wild birds. Please consult the Wildlife Health Australia (WHA) report in this publication for information on avian influenza in wild birds.

During the quarter, 805 birds from 105 laboratory submissions were tested for avian influenza (excluding surveillance reported in the WHA report and Northern Australia Quarantine Strategy reports); one positive for non-H5, non-H7 strain was detected (Table 11). Tests include competitive ELISA, haemagglutination inhibition, agar gel immunodiffusion, reverse-transcriptase PCR and virus isolation.

Table 11 Results of testing for avian influenza virus in poultry, 1 July – 30 September 2015a

H5 positive H7 positive Positive for a non-H5, non-H7 strain

0 0 1

a Excludes surveillance reported in the Wildlife Health Australia and Northern Australia Quarantine Strategy reports and testing conducted for import purposes.

Newcastle diseaseAustralia is currently free from virulent Newcastle disease or exotic Newcastle disease, even though precursor and endemic avirulent viruses are present in Australia. Vaccination against virulent Newcastle disease using a combination of live lentogenic virus (V4) and a killed vaccine is required in commercial chicken flocks in all Australian jurisdictions. Vaccination exceptions for broilers apply in Tasmania, Western Australia, Queensland and South Australia.

During the quarter, 770 birds from 97 laboratory submissions were tested for Newcastle disease (Table 12).

Table 12 Results of testing for paramyxovirus testing in poultry, 1 July – 30 September 2015a

Virulent strain of ND virus

Peats Ridge strain of ND

virus

Lentogenic V4 or V4-like strain

of ND virusOther

paramyxovirus

0 0 0 0

a Excludes testing for import purposes.

27Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Salmonella surveillanceThe National Enteric Pathogen Surveillance Scheme (NEPSS) is operated and maintained on behalf of the Australian Government and state and territory governments by the Microbiological Diagnostic Unit at the University of Melbourne. Data on isolates of Salmonella spp. and other pathogens are submitted to NEPSS from participating laboratories around Australia. Annual reports of both human and nonhuman isolates are available on request and detailed data searches are provided on request to NEPSS. Table 13 summarises Salmonella spp. isolations from animals reported to NEPSS.

Table 13 Salmonella notifications reported to the National Enteric Pathogen Surveillance Scheme (NEPSS), 1 July – 30 September 2015

Salmonella serovar Birdsa Cats Cattle Dogs Horses Pigs Sheep Other Total

Bovismorbificans 0 0 24 0 0 0 1 0 25

Dublin 0 0 29 0 0 0 0 0 29

Infantis 0 0 0 0 0 0 0 0 0

Typhimurium 3 20 81 13 3 6 1 0 127

Other 1 0 60 15 6 29 1 7 119

Total 4 20 194 28 9 35 3 7 300

a Includes both poultry and wild birds.

Northern Australian Quarantine StrategyIn recognition of the unique biosecurity risks associated with Australia’s extensive and sparsely populated northern coastline, the Australian Government Department of Agriculture and Water Resources conducts an animal disease surveillance program as an integral component of its Northern Australia Quarantine Strategy (NAQS). This surveillance program aims to provide early detection of exotic and emerging pests and diseases of significance to agriculture, public health and the environment. Information is derived from the use of sentinel animals, structured surveys, vector trapping and community reporting projects. In addition, NAQS contributes surveillance data to the National Arbovirus Monitoring Program and the electronic Wildlife Health Information System (eWHIS). Table 14 summarises NAQS animal testing for specific target diseases in Australia during the past five quarters.

Table 14 Disease testing and pest surveillance under the Northern Australia Quarantine Strategy (NAQS), 1 July 2014 – 30 September 2015

Disease or pest

Jul–Sep 2014 Oct–Dec 2014 Jan–Mar 2015 Apr–Jun 2015 Jul–Sep 2015

Tested Positive Tested Positive Tested Positive Tested Positive Tested Positive

Aujeszky’s diseasea 0 0 0 0 0 0 31 0 73 0

Avian influenza 0 0 0 0 0 0 48 0 0 0

Classical swine fever 132 0 122 0 0 0 252 0 73 0

Japanese encephalitis 0 0 0 0 22 0 42 0 0 0

Surra (Trypanosoma evansi) 129 0 54 0 0 0 278 0 73 0

a The NAQS surveillance strategy for Aujeszky’s disease has recently been reviewed and serological screening of wild pig populations commenced in the April–June 2015 quarter. Prior surveillance was based on general strategies for detecting disease events in pig populations.

28 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Screw-worm Fly Surveillance and Preparedness ProgramThe Old World screw-worm fly (OWS) and New World screw-worm fly (NWS), Chrysomya bezziana and Cochliomyia hominivorax respectively, are exotic to Australia and suspicion of infestation in animals is notifiable under state and territory animal health legislation13. The OWS is a significant production disease of livestock throughout its range and is considered a greater threat to Australian livestock industries than NWS due to the proximity of its distribution to Australia (potential entry through the Torres Strait) and traffic of livestock export vessels returning from Asia to Australian ports.

Surveillance is conducted by targeted fly trapping and livestock myiasis monitoring in addition to unplanned investigation of myiasis (reported in Suspect exotic or emergency disease investigations and Table 15). Fly trapping is conducted at locations suitable for local OWS establishment following a potential incursion; in areas neighbouring livestock export ports and the Northern Peninsula Area. Table 15 summarises fly trapping events over the past year14. No screw- worm fly were detected. Further information on the screw-worm fly program is available on the Animal Health Australia website15.

Table 15 Summary of fly trapping events conducted, 1 October 2014 – 30 September 2015a

Risk entry pathway Conducted by Oct–Dec 2014 Jan–Mar 2015 Apr–Jun 2015 Jul–Sep 2015

Torres Strait NAQS 31 35 23 15

Livestock export ports NT, Qld and WA governments 78 268 24 37

NAQS = Northern Australia Quarantine Strategy; NT = Northern Territory; Qld = Queensland; WA = Western Australia

a Excludes traps with identification results pending.

Public healthThe National Notifiable Diseases Surveillance System (NNDSS) coordinates the national surveillance of more than 50 communicable diseases or disease groups. Unit records of disease notifications made to the state or territory health authority, under the provisions of the public health legislation in their jurisdiction, are supplied daily to the Office of Health Protection, Australian Government Department of Health. The data are published weekly on the NNDSS website16 and quarterly in the journal Communicable Diseases Intelligence and are replicated in Animal Health Surveillance Quarterly (Table 16) for five important zoonoses.

Table 16 National notifications of five zoonotic infections in humans, 1 July 2014 – 30 September 2015

Quarter Brucellosisa Chlamydophilosisb Leptospirosis Listeriosis Q fever

Jul–Sep 2014 4 5 15 18 98

Oct–Dec 2014 3 12 11 19 94

Jan–Mar 2015 1 1 20 16 129

Apr–Jun 2015 5 2 17 18 127

Jul–Sep 2015

ACT 0 0 0 0 0

NSW 1 0 4 3 71

NT 1 0 0 0 0

Qld 1 0 11 2 56

SA 0 0 0 1 3

Tas 0 0 0 0 0

Vic 0 3 1 4 13

WA 0 0 1 4 5

Aus 3 3 17 14 148

a Bovine brucellosis (Brucella abortus) was eradicated from the Australian cattle herd in 1989 and is presently considered an exotic animal disease in Australia. Caprine and ovine brucellosis (caused by B. melitensis) has never been reported in Australian sheep or goats. Swine brucellosis (caused by B. suis) iis prevalent in small areas of northern Australia and northern New South Wales where it occurs in feral pigs, with human cases predominantly seen in recreational feral pig hunters.

b Also known as ‘psittacosis’ or ‘ornithosis’.

13 Australian Government Department of Agriculture. National List of Notifiable Animal Diseases. 2015 [updated 30 Mar 2015; cited 18 May 2015]. Available from: www.agriculture.gov.au/pests-diseases-weeds/animal/notifiable.

14 Does not include traps with identification results pending.

15 Animal Health Australia. Screw-worm Fly Surveillance and Preparedness Program. 2015 [updated 2015; cited 2015]. Available from: www.animalhealthaustralia.com.au/swf.

16 www9.health.gov.au/cda/source/cda-index.cfm.

29Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Suspect exotic or emergency disease investigationsDuring the quarter, 128 investigations of diseases were reported (Table 17) that were suspected to be either exotic or possible emergency diseases. Note that a single investigation may involve more than one animal. More details about the investigations can be found in the state and territory reports or from the relevant state or territory coordinator (see contact details on last page). Further information regarding Australia’s emergency animal disease preparedness and management can be found at www.agriculture.gov.au/animal-plant-health/emergency.

Table 17 Investigations of suspect emergency animal diseases listed on Australia’s National List of Notifiable Animal Diseases, 1 July – 30 September 2015

Disease Species State MonthResponse codea Finding

African swine fever Pig SA Sep 3 NegativeAmerican foulbrood (Paenibacillus larvae)

Bees Qld Aug 2 Positive (6 unrelated investigations)Bees Qld Aug 2 Negative (5 unrelated investigations)Bees Qld Jul 2 Positive (4 unrelated investigations)Bees Qld Jul 2 Negative (3 unrelated investigations)Bees Qld Sep 2 Negative (6 unrelated investigations)Bees Qld Sep 2 Positive (6 unrelated investigations)

Anaplasmosis in tick free areas Cattle Qld Aug 2 PositiveCattle Qld Sep 2 Positive

Aujeszky’s disease Pig SA Sep 3 NegativeAustralian bat lyssavirus Dog WA Sep 3 Negative

Donkey Qld Aug 2 NegativeDonkey Qld Sep 2 NegativeHorse Qld Aug 2 Negative (7 unrelated investigations)Horse Qld Jul 2 Negative (3 unrelated investigations)Horse Qld Sep 2 Negative (4 unrelated investigations)

Babesiosis in tick-free areas Cattle NSW Aug 2 NegativeCattle NSW Jul 2 Negative (2 unrelated investigations)Cattle NSW Sep 2 Negative (3 unrelated investigations)Cattle Qld Aug 2 PositiveCattle Qld Sep 2 PositiveDeer NSW Sep 2 Negative

Bluetongue — clinical disease Cattle NSW Aug 2 NegativeCattle NSW Sep 2 NegativeSheep NSW Aug 2 NegativeSheep NSW Jul 2 NegativeSheep NSW Sep 2 NegativeSheep SA Sep 3 NegativeSheep WA Aug 3 Negative (6 unrelated investigations)Sheep WA Jul 3 Negative (3 unrelated investigations)

Bovine virus diarrhoea type 2 Cattle WA Jul 3 NegativeBrucellosis (Brucella abortus, B. suis, B. canis and B. melitensis)

Cattle WA Aug 3 Negative (2 unrelated investigations)Cattle WA Jul 2 Negative (2 unrelated investigations)Cattle WA Jul 3 NegativeCattle WA Sep 2 Negative (3 unrelated investigations)Dog NSW Aug 2 Negative (12 unrelated investigations)Dog NSW Jul 2 Negative (11 unrelated investigations)Dog NSW Jul 2 Positiveb

Dog NSW Sep 2 Negative (9 unrelated investigations)Dog NSW Sep 2 Positive (2 unrelated investigations)Dog Qld Aug 2 Positiveb

Goat Qld Sep 2 NegativeHorse NSW Aug 2 NegativePig NSW Jul 2 NegativeSheep Vic Aug 2 Negative (6 unrelated investigations)Sheep Vic Jul 2 Negative (18 unrelated investigations)Sheep Vic Sep 2 Negative (4 unrelated investigations)

30 Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Disease Species State MonthResponse codea Finding

Classical swine fever Pig SA Sep 3 NegativeContagious equine metritis Horse NSW Sep 2 NegativeEast Coast fever (Theileria parva) and Mediterranean theileriosis (Theileria annulata)

Cattle WA Sep 2 Negative

Enzootic abortion of ewes Sheep WA Jul 2 NegativeEnzootic bovine leucosis Cattle NSW Aug 2 Negative

Cattle NSW Jul 2 Negative (2 unrelated investigations)Cattle NSW Sep 2 Negative

Equine encephalomyelitis (eastern, western and Venezuelan)

Horse WA Aug 3 Negative (2 unrelated investigations)

Equine influenza Horse NSW Sep 2 NegativeEuropean foulbrood (Melissococcus pluton)

Bees Qld Aug 2 Positive (3 unrelated investigations)Bees Qld Aug 2 Negative (8 unrelated investigations)Bees Qld Jul 2 Negative (7 unrelated investigations)Bees Qld Sep 2 Negative (9 unrelated investigations)Bees Qld Sep 2 Positive (3 unrelated investigations)

Foot-and-mouth disease Cattle NSW Aug 3 Negative (2 unrelated investigations)Cattle Vic Aug 3 NegativeCattle Vic Sep 2 NegativeCattle Vic Sep 3 NegativeCattle WA Jul 3 Negative (2 unrelated investigations)Sheep NSW Aug 3 Negative (2 unrelated investigations)Sheep NSW Sep 2 NegativeSheep NSW Sep 3 NegativeSheep SA Sep 3 NegativeSheep Vic Jul 3 NegativeSheep Vic Sep 3 Negative (2 unrelated investigations)Sheep WA Aug 3 Negative

Hendra virus infection Dog NSW Sep 2 NegativeDog Qld Jul 5 NegativeDog WA Sep 3 NegativeDonkey Qld Aug 2 NegativeDonkey Qld Sep 2 Negative (2 unrelated investigations)Horse NSW Aug 2 Negative (39 unrelated investigations)Horse NSW Jul 2 Negative (36 unrelated investigations)Horse NSW Sep 2 Negative (44 unrelated investigations)Horse NSW Sep 3 PositiveHorse NT Jul 2 Negative (3 unrelated investigations)Horse Qld Aug 2 Negative (85 unrelated investigations)Horse Qld Aug 5 NegativeHorse Qld Jul 2 Negative (91 unrelated investigations)Horse Qld Jul 5 Negative Horse Qld Jul 5 PositiveHorse Qld Sep 2 Negative (88 unrelated investigations)Horse Vic Aug 2 Negative (3 unrelated investigations)Horse Vic Aug 3 Negative Horse Vic Sep 3 Negative (2 unrelated investigations)Horse WA Aug 2 Negative Horse WA Aug 3 Negative Horse WA Jul 2 Negative Horse WA Sep 2 Negative (2 unrelated investigations)

Menangle virus infection Pig SA Sep 3 Negative

Table 17 Continued

31Animal Health Surveillance Quarterly | Volume 20 | Issue 3

Table 17 Continued

Disease Species State MonthResponse codea Finding

Paratuberculosis — Johne’s disease Cattle Vic Aug 2 NegativeCattle Vic Jul 2 Negative (2 unrelated investigations)Cattle Vic Sep 2 NegativeGoat Vic Aug 2 Negative (2 unrelated investigations)Sheep Vic Aug 2 Negative (2 unrelated investigations)Sheep Vic Jul 2 Negative

Porcine reproductive and respiratory syndrome

Pig SA Sep 3 NegativePig WA Aug 3 Negative

Post-weaning multisystemic wasting syndrome

Pig SA Sep 3 Negative

Rabies Dog WA Sep 3 NegativeScrew-worm fly — Old World (Chrysomya bezziana)

Cattle WA Aug 2 Negative

Salmonellosis (Salmonella abortusovis)

Sheep WA Aug 3 NegativeSheep WA Jul 2 NegativeSheep WA Sep 2 Negative

Swine influenza Pig SA Sep 3 NegativePig Vic Jul 3 Negative

Tuberculosis (Mycobacterium bovis)c Cattle NSW Jul 2 Negative (1 granulomas examined)Cattle Qld Jul 2 Negative (5 granulomas examined)Cattle Tas Jul 2 Negative (1 granulomas examined)Cattle Vic Jul 2 Negative (3 granulomas examined)

Varroosis (Varroa destructor) Bees Vic Aug 2 NegativeVesicular stomatitis Cattle NSW Aug 3 Negative (2 unrelated investigations)

Cattle Vic Aug 3 NegativeCattle Vic Sep 3 Negative (2 unrelated investigations)Cattle WA Jul 3 Negative (2 unrelated investigations)Sheep NSW Aug 3 Negative (2 unrelated investigations)Sheep NSW Sep 3 Negative (2 unrelated investigations)Sheep SA Sep 3 NegativeSheep Vic Jul 3 NegativeSheep Vic Sep 3 Negative (2 unrelated investigations)

West Nile virus infection — clinical Horse Qld Jul 3 NegativeHorse Vic Aug 3 NegativeHorse WA Aug 3 Negative

a Key to response codes

1 = Field investigation by government officer

2 = Investigation by state or territory government veterinary laboratory

3 = Specimens sent to the CSIRO Australian Animal Health Laboratory (or CSIRO Entomology)

4 = Specimens sent to reference laboratories overseas

5 = Regulatory action taken (biosecurity or police officers)

6 = Alert or standby

7 = Eradication

b Infection with B. suis occurs rarely in dogs that have had contact with feral pigs or their products.

c www.agriculture.gov.au/SiteCollectionDocuments/animal-plant/animal-health/pet-food-safety/tb-28feb12.pdf

Animal Health Australia is a not-for-profit public company established by the Australian Government, state and territory governments, and major national livestock industry organisations to manage national animal programs on behalf of its

members. Every effort is made to ensure that the information in Animal Health Surveillance Quarterly is accurate at the time of publication; however, it is subject to change as a result of additional or amended data being received. Further information on

the outcome of cases that were pending at the time of printing may be found at www.animalhealthaustralia.com.au/ahsq. To receive an email notification of new editions, contact ahsq@animalhealthaustralia.com.au.

Editing: Viscarra Rossel & Associates. Design: KGR Design. Front cover photo: Animal Health Australia

Animal Health SurveillanceQ U A R T E R L Y

There were 651 calls to the Emergency Animal Disease Watch Hotline during the quarter.

The Emergency Animal Disease Watch Hotline is a toll-free telephone number that connects callers to the relevant state

or territory officer to report concerns about any potential disease situation.

Anyone suspecting an exotic disease outbreak should use this number to get immediate advice and assistance.

National Animal Health Information System contactsThe National Animal Health Information System (NAHIS) collects summaries of animal health information from many sources; detailed data are maintained by the source organisations. Please contact the relevant person below if further details are required. NAHIS is on the internet (nahis.animalhealthaustralia.com.au).

Name Role Phone Email

Ian Langstaff NAHIS Program Manager 02 6203 3909 ILangstaff@animalhealthaustralia.com.au

Brett Herbert Aquatic Animal Health 02 6272 5402 Brett.Herbert@agriculture.gov.au

Belinda Wright Australian Government NAHIS Coordinator 02 6272 3640 Belinda.Wright@agriculture.gov.au

Venessa McEniery Australian Milk Residue Analysis Survey 03 9810 5930 VMcEniery@dairysafe.vic.gov.au

Tiggy Grillo Wildlife Health Australia 02 9960 7444 TGrillo@wildlifehealthaustralia.com.au

Janet Strachan National Enteric Pathogens Surveillance Scheme

03 8344 5713 JanetES@unimelb.edu.au

Mark Trungove National Notifiable Diseases Surveillance System

02 6289 8315 Mark.Trungove@health.gov.au

Megan Wyllie Surveillance Information Coordinator 02 6203 3954 MWyllie@animalhealthaustralia.com.au

Rob Barwell Johne’s Disease Project Coordinator 02 6203 3947 RBarwell@animalhealthaustralia.com.au

Beth Cookson Northern Australia Quarantine Strategy 07 42417853 Beth.Cookson@agriculture.gov.au

State and territory coordinators

Rory Arthur New South Wales 02 6391 3687 Rory.Arthur@dpi.nsw.gov.au

Susanne Fitzpatrick Northern Territory 08 8999 2123 Susanne.Fitzpatrick@nt.gov.au

Greg Williamson Queensland 07 3330 4545 Greg.Williamson@daf.qld.gov.au

Celia Dickason South Australia 08 8207 7807 Celia.Dickason@sa.gov.au

Mary Lou Conway Tasmania 03 6233 6330 Marylou.Conway@dpipwe.tas.gov.au

Karen Moore Victoria 03 5430 4525 Karen.Moore@ecodev.vic.gov.au

Jamie Finkelstein Western Australia 08 9368 3805 Jamie.Finkelstein@agric.wa.gov.au

EMERGENCY ANIMAL DISEASE WATCH HOTLINE

1800 675 888