Epizootic of Mucopurulent Nasal Discharge in African Hoofstock

Epizootic of Epizootic of Mucopurulent Nasal Mucopurulent Nasal Discharge in African Discharge in African

HoofstockHoofstock

L.J. VenterL.J. Venter

South AfricaSouth Africa

Addra Gazelle, Addra Gazelle, Gazella dama Gazella dama ruficollisruficollis

Cape Buffalo, Cape Buffalo, Syncerus caffer Syncerus caffer caffercaffer

Black-faced Impala, Black-faced Impala, Aepyceros melampus petersiAepyceros melampus petersi

Indian Guar, Indian Guar, Bos FrontalisBos Frontalis

EnclosuresEnclosures

5 confirmed cases occurred in 4 5 confirmed cases occurred in 4 enclosuresenclosures Areas ranged from 300mAreas ranged from 300m22 to 2500 m to 2500 m22

All enclosures have night-quarter facilitiesAll enclosures have night-quarter facilities Enclosure 41Enclosure 41 Enclosure 126 & 127Enclosure 126 & 127 Enclosure 138Enclosure 138 Enclosure 162Enclosure 162

Black-faced ImpalaBlack-faced Impala

Clinical signs and historyClinical signs and history Intermittent episodes of weakness and Intermittent episodes of weakness and

lethargy for 2 monthslethargy for 2 months Admitted to hospital in a state of collapse and Admitted to hospital in a state of collapse and

died during initial treatmentdied during initial treatment

Gross Necropsy FindingsGross Necropsy Findings

Mild icterus and mild fibrinous ascites in the Mild icterus and mild fibrinous ascites in the carcass carcass

Severe, generalized lymphadenopathySevere, generalized lymphadenopathy Abomasal ulcerationAbomasal ulceration Moderate, diffuse, sub-acute hepatitis with Moderate, diffuse, sub-acute hepatitis with

cholestasischolestasis Mild nephrosisMild nephrosis Mild splenic atrophyMild splenic atrophy Diffuse, severe pulmonary congestion and Diffuse, severe pulmonary congestion and

edemaedema

HistopathologyHistopathology

Severe, multifocal perivasculitisSevere, multifocal perivasculitis Fibrinous necrotizing vasculitisFibrinous necrotizing vasculitis Lymphoid hyperplasiaLymphoid hyperplasia Necrotizing enteritisNecrotizing enteritis Severe purulent interstitial pneumoniaSevere purulent interstitial pneumonia Pulmonary edema, hemorrhage, Pulmonary edema, hemorrhage,

microemboli, alveolar necrosis, atelectasismicroemboli, alveolar necrosis, atelectasis

Cape Buffalo-1Cape Buffalo-1

Clinical Signs and historyClinical Signs and history 12 days listlessness, mucopurulent nasal 12 days listlessness, mucopurulent nasal

discharge, excessive lacrimation, discharge, excessive lacrimation, blepharospasm, corneal opacity, ataxiablepharospasm, corneal opacity, ataxia


Mild cachexiaMild cachexia Focal ulcerations of buccal mucosaFocal ulcerations of buccal mucosa Mild to moderate, diffuse, edema and Mild to moderate, diffuse, edema and

congestion of the lungscongestion of the lungs Moderate, chronic, localized caseous Moderate, chronic, localized caseous

necrotis omasitisnecrotis omasitis


Focal to focally-extensive, severe, chronic Focal to focally-extensive, severe, chronic necrogranulomatous myositisnecrogranulomatous myositis

Brain, spinal cord, meninges: mild diffuse Brain, spinal cord, meninges: mild diffuse congestion and edemacongestion and edema

Mild, multifocal lymphocytic perivasculitisMild, multifocal lymphocytic perivasculitis Moderate, multifocal necrogranulomatous Moderate, multifocal necrogranulomatous

lymphangitis of mesenteric lymph nodeslymphangitis of mesenteric lymph nodes Multifocal interstitial lymphocytic nephritisMultifocal interstitial lymphocytic nephritis


PCR indicated Wildebeest strain of MCFPCR indicated Wildebeest strain of MCF No wildebeest at Pretoria for 20 yearsNo wildebeest at Pretoria for 20 years Test repeated 5 times on different tissues, Test repeated 5 times on different tissues,

same resultssame results


Clinical Signs and historyClinical Signs and history CoughingCoughing Severe mucopurulent nasal dischargeSevere mucopurulent nasal discharge Corneal opacityCorneal opacity Light sensitivityLight sensitivity LacrimationLacrimation


DiagnosticsDiagnostics Animal immobilizedAnimal immobilized

BronchoscopyBronchoscopy Severe tracheobronchitis Severe tracheobronchitis

with diptheritic membranewith diptheritic membrane

TreatmentTreatment Extensive antibiotic therapy for 2 weeksExtensive antibiotic therapy for 2 weeks

OutcomeOutcome Euthanasia for humane reasonsEuthanasia for humane reasons


Severe diffuse keratitisSevere diffuse keratitis Moderate conjunctivitisModerate conjunctivitis Muzzle and nostrils: Muzzle and nostrils:

Mild, multifocal hyperkeratosis and exudative Mild, multifocal hyperkeratosis and exudative dermatitis with crust formationdermatitis with crust formation

Severe, acute, diffuse fibrinopurulent Severe, acute, diffuse fibrinopurulent rhinitis with hyperemia of the mucous rhinitis with hyperemia of the mucous membranes and turbinatesmembranes and turbinates

Gross necropsy Findings--Gross necropsy Findings--con’tcon’t

Severe, acute, diffuse fibrinohemorrhagic Severe, acute, diffuse fibrinohemorrhagic pharyngitis, laryngitis, and tracheitispharyngitis, laryngitis, and tracheitis

Severe, diffuse congestion and edema Severe, diffuse congestion and edema with fibrinopurulent bronchopneumonia of with fibrinopurulent bronchopneumonia of the apical and cardiac lung lobesthe apical and cardiac lung lobes

Severe Severe Sarcocystis Sarcocystis sp. infection of the sp. infection of the gluteal musclegluteal muscle

HistopathologyHistopathology BrainBrain: Mild, multifocal, subacute lymphocytic : Mild, multifocal, subacute lymphocytic

perivasculitisperivasculitis EyeEye: Severe, multifocal-to-coalescing subacute to : Severe, multifocal-to-coalescing subacute to

chronic rhinotracheitis with mucosal and vascular chronic rhinotracheitis with mucosal and vascular necrosis.necrosis.

LungsLungs: Severe, multifocal to coalescing, subacute to : Severe, multifocal to coalescing, subacute to chronic bronchointerstitial pneumonia with alveolar, chronic bronchointerstitial pneumonia with alveolar, bronchial, and vascular necrosisbronchial, and vascular necrosis

KidneysKidneys: Mild to moderate, subacute lymphocytic : Mild to moderate, subacute lymphocytic nephritis with interstitial and periglomerular infiltration of nephritis with interstitial and periglomerular infiltration of lymphoid cellslymphoid cells

Skeletal MuscleSkeletal Muscle: Hemorrhage, necrosis, and edema as : Hemorrhage, necrosis, and edema as well as scattered well as scattered Sarcocystis Sarcocystis spp. parasitesspp. parasites

Addra GazelleAddra Gazelle

Clinical Signs and historyClinical Signs and history ListlessnessListlessness AnorexiaAnorexia Regurgitation of rumenal fluidRegurgitation of rumenal fluid Abnormal high stepping gait, chewing gum fits Abnormal high stepping gait, chewing gum fits

over a period of 4 daysover a period of 4 days OutcomeOutcome

Humane euthanasiaHumane euthanasia


Moderate congestion of the carcassModerate congestion of the carcass Severe, acute, locally extensive necrotic Severe, acute, locally extensive necrotic

bronchopneumnia involving the right bronchopneumnia involving the right cranioventral lung lobe.cranioventral lung lobe.

No gross lesions of the upper alimentary No gross lesions of the upper alimentary systemsystem


Lungs: Acute bronchopneumoniaLungs: Acute bronchopneumonia Liver: Focal hepatocellular necrosisLiver: Focal hepatocellular necrosis Kidneys: moderate nephrosis and cast Kidneys: moderate nephrosis and cast

formationformation

Indian GuarIndian Guar

Clinical Signs and historyClinical Signs and history No history of illnessNo history of illness Animal found dead in the enclosure with two Animal found dead in the enclosure with two

penetration wounds cranial to the scrotumpenetration wounds cranial to the scrotum


Penetration wounds present cranial to Penetration wounds present cranial to scrotum, portions of the small intestines scrotum, portions of the small intestines had herniated through one of the holeshad herniated through one of the holes

Herniated small intestine was intensly Herniated small intestine was intensly congested with frank blood in the lumencongested with frank blood in the lumen

Another penetrating wound was found in Another penetrating wound was found in the left flankthe left flank

Gross Necropsy findings--Gross Necropsy findings--con’tcon’t

A large blood clot and rumenal contents were A large blood clot and rumenal contents were present in the abdomenpresent in the abdomen

Fibrin strands were visible on the serosal Fibrin strands were visible on the serosal surface of the abdominal organssurface of the abdominal organs

Penetrating wounds were seen in the rumen and Penetrating wounds were seen in the rumen and in the portion of herniated intestinein the portion of herniated intestine

A single penetrating wound was seen in the A single penetrating wound was seen in the rectal wallrectal wall


CNSCNS: Mild, subacute meningitis: Mild, subacute meningitis Lymph nodesLymph nodes: Peripheral nodes exhibited : Peripheral nodes exhibited

marked follicular atrophy, with medullary marked follicular atrophy, with medullary histiocytosishistiocytosis

CardiacCardiac: Myocardium had multifocal : Myocardium had multifocal interstitial accumulations of lymphocytes interstitial accumulations of lymphocytes were visible as well as focal areas of acute were visible as well as focal areas of acute myocardial necrosismyocardial necrosis

Five PCR Confirmed CasesFive PCR Confirmed Cases

Addra GazelleAddra Gazelle Cape Buffalo (2)Cape Buffalo (2) Black Faced ImpalaBlack Faced Impala Indian GuarIndian Guar

BackgroundBackground

1990-20031990-2003 21 Cases of MCF reported in 9 different 21 Cases of MCF reported in 9 different

species in the National Zoological Gardens of species in the National Zoological Gardens of South AfricaSouth Africa

5 Asia Deer5 Asia Deer 4 Cape Buffalo4 Cape Buffalo 3 Indian Guar (Asiatic Ox)3 Indian Guar (Asiatic Ox) 2 American Bison, Pere David Deer2 American Bison, Pere David Deer 1 each of Barbary Sheep, European Bison, Addra 1 each of Barbary Sheep, European Bison, Addra

Gazelle, Black Faced Impala, KuduGazelle, Black Faced Impala, Kudu

BackgroundBackground

Five cases were confirmed as MCF by Five cases were confirmed as MCF by PCRPCR Highly specific and sensitive for MCFHighly specific and sensitive for MCF These cases will be discussedThese cases will be discussed

Remainder of the cases were diagnosed Remainder of the cases were diagnosed based on:based on: Clinical signsClinical signs Macroscopic pathologyMacroscopic pathology HistopathologyHistopathology

Malignant Catarrhal FeverMalignant Catarrhal Fever

Acute, sporadic, invariably fatal disease of Acute, sporadic, invariably fatal disease of Bovidae and CervidaeBovidae and Cervidae

Agents implicated in causing diseaseAgents implicated in causing disease Alcephaline herpes virus I (AHV-I)Alcephaline herpes virus I (AHV-I)

Associated with the wild blue wildebeestAssociated with the wild blue wildebeest Occurs only in AfricaOccurs only in Africa ““Wildebeest-derived” MCFWildebeest-derived” MCF

Ovine herpes virus II (OHV-II)Ovine herpes virus II (OHV-II) Occurs worldwideOccurs worldwide ““Sheep-associated” MCFSheep-associated” MCF

MCF-TransmissionMCF-Transmission

AHV-IAHV-I Horizontally and vertically in wildebeest herds, Horizontally and vertically in wildebeest herds,

calves may be infected calves may be infected in uteroin utero Wildebeest develop no clinical signsWildebeest develop no clinical signs Fomites are largest source of disease Fomites are largest source of disease

transmissiontransmission Virus excreted in nasal/ocular discharge and Virus excreted in nasal/ocular discharge and

fecesfeces

MCF-Transmission--con’tMCF-Transmission--con’t

Similar mode of transmission in sheepSimilar mode of transmission in sheep Susceptible ruminants are end-hosts which develop Susceptible ruminants are end-hosts which develop

clinical signs of the disease but DO NOT spread the clinical signs of the disease but DO NOT spread the disease horizontally within susceptible populationdisease horizontally within susceptible population

Sub-clinical infection in cattle and deer has been Sub-clinical infection in cattle and deer has been described with clinical manifestations under severe described with clinical manifestations under severe stressstress

Close contact with wildebeest is NOT a prerequisite for Close contact with wildebeest is NOT a prerequisite for the development of the disease in cattlethe development of the disease in cattle

Minimum separation distance of 1000m is suggested Minimum separation distance of 1000m is suggested between wildebeest and cattlebetween wildebeest and cattle

MCF-Clinical SignsMCF-Clinical Signs

Varies from sub-acute to chronicVaries from sub-acute to chronic Deer: Per-acute diseaseDeer: Per-acute disease Cattle: Acute diseaseCattle: Acute disease

Signs in acute formSigns in acute form Fever, depression, lymphadenopathy, serous to Fever, depression, lymphadenopathy, serous to

mucopurulent nasal and ocular discharge, oral mucopurulent nasal and ocular discharge, oral ulcerations and erosions, corneal opacity, diarrhea, ulcerations and erosions, corneal opacity, diarrhea, ulceration of the skin of the perineum, vulva, coronet, ulceration of the skin of the perineum, vulva, coronet, and interdigital area, epithelial necrosis, interstitial and interdigital area, epithelial necrosis, interstitial infiltration of organs by lymphocytes and widespread infiltration of organs by lymphocytes and widespread angiitisangiitis

CNS signs: hyperaesthesia, hypermetria, tremors and CNS signs: hyperaesthesia, hypermetria, tremors and convulsionsconvulsions

MCF-DiagnosisMCF-Diagnosis

Relies on observation of clinical signs and Relies on observation of clinical signs and herd signalmentherd signalment

Macroscopic necropsy examinationMacroscopic necropsy examination Histologic observationHistologic observation Serologic investigation and PCR are Serologic investigation and PCR are

added diagnostic modalitiesadded diagnostic modalities

ControlControl

2 Sheep kept 30m behind the buffalo enclosure 2 Sheep kept 30m behind the buffalo enclosure (126 & 127) in the petting zoo(126 & 127) in the petting zoo Sold, no PCR tests performedSold, no PCR tests performed

Movement of ungulates in and out of zoo was Movement of ungulates in and out of zoo was restrictedrestricted

Relevant personnel have been informed about Relevant personnel have been informed about characteristics of MCF and are on heightened characteristics of MCF and are on heightened alert for signs of the disease in all ungulate alert for signs of the disease in all ungulate speciesspecies

PCR is part of the tests before any buffalo are PCR is part of the tests before any buffalo are moved, not yet required by lawmoved, not yet required by law

MCF-PreventionMCF-Prevention

Separation of susceptible animals from Separation of susceptible animals from source of infection is the ONLY RELIABLE source of infection is the ONLY RELIABLE way of preventing the diseaseway of preventing the disease

Comments and DiscussionComments and Discussion

Interesting that Guar showed no clinical Interesting that Guar showed no clinical signssigns Killed by the bull in the enclosureKilled by the bull in the enclosure Did the animal have the per-acute form that Did the animal have the per-acute form that

lead to a change in behavior that caused the lead to a change in behavior that caused the bull to attack it? This is reported to happen in bull to attack it? This is reported to happen in wild animals.wild animals.


The pathologists report for the Addra The pathologists report for the Addra comments mainly on the comments mainly on the bronchopneumonia and few “classic” signs bronchopneumonia and few “classic” signs of MCF are described.of MCF are described. As this diagnosis was made on PCR could it As this diagnosis was made on PCR could it

be possible that the animal was a carrier?be possible that the animal was a carrier?


Except for the one, buffalo all PCR results Except for the one, buffalo all PCR results indicated OHV-II as the cause of the indicated OHV-II as the cause of the diseasedisease This unexpected PCR result causes one to This unexpected PCR result causes one to

speculate on the existence of a possible AHV-speculate on the existence of a possible AHV-I carrier apart from wildebeest in the zoo.I carrier apart from wildebeest in the zoo.

SPECIES COMMON NAME ID AGE SEX DATE OF DEATHDIAGNOSTIC METHOD COMMENT Pathologist

Aepyceros melampus petersi Black-faced impala 909803 4m 14.05.2003 PCR Ovine strain Neser

Syncerus caffer caffer Cape Buffalo 905220 12y,3m M 06.06.2003 PCRWildebeest strain Neser

Syncerus caffer caffer Cape Buffalo 902064 11y,4m F 06.03.2003 PCR Ovine strain NeserBos frontalis Indian Gaur 906964 5m M 29.07.1998 PCR Ovine strain PearsonGazella dama ruficollis Addra Gazelle 900148 10y,2m M 11.07.1998 PCR Ovine strain vd LugtBos frontalis Indian Gaur 903849 4y,7m F 20.05.1998 Histopathology SND WilliamsBison bonasus bonasus European Bison 900047 8y,2m F 05.12.1995 Histopathology SND WilliamsAxis axis Axis deer 904496 1m F 01.10.1994 Histopathology SND CollettBos frontalis Indian Gaur 903716 3y,1m F 04.07.1994 Histopathology SND PearsonAxis axis Axis deer 900106 13y,9m F 11.05.1994 Histopathology SND NesbitAxis axis Axis deer 902764 2m F 11.09.1992 Histopathology SND NesbitTragelaphus strepsiceros Kudu 900208 4y,5m F 03.06.1992 Histopathology SND NesbitAxis axis Axis deer 900098 11y,10m M 15.11.1991 Histopathology SND NesbitSyncerus caffer caffer Cape Buffalo 901322 8m M 06.11.1991 Histopathology SND NesbitAxis axis Axis deer 900809 1y,2m F 01.11.1991 Histopathology SND NesbitSyncerus caffer caffer Cape Buffalo 900067 2y,7m F 16.09.1991 Histopathology SND NesbitBison bison American bison 900042 16y,4m M 04.05.1991 Histopathology SND WilliamsBison bison American bison 900043 16y,2m F 30.03.1991 Histopathology SND NesbitElaphurus davidianus Pere David's deer 901076 5m M 12.03.1991 Histopathology SND KriekElaphurus davidianus Pere David's deer 900123 13y,1m F 27.02.1991 Histopathology SND NesbitAmmotragus lervia Barbary sheep 900976 2m M 22.11.1990 Histopathology SND Unknown

Documents

Epizootic of Mucopurulent Nasal Discharge in African Hoofstock