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Foreign Animal Diseases in Poultry
Angie DementExtension Associate for Veterinary MedicineTexas AgriLife Extension ServiceThe Texas A&M Systemhttp://aevm.tamu.edu
Improving Lives. Improving Texas.
“Avian Flu” “Bird Flu”Viral diseaseTwo classifications or forms• Low-pathogenic avian influenza (LPAI)
– risk to poultry industry– reportable– endemic disease– most common class
• High-pathogenic avian influenza (HPAI)– serious damage to poultry industry– reportable– epidemic disease
Disease severity and symptoms determine class
Zoonotic disease (Rare)• HPAI class• Mutates – potentially infectious to
people•limited bird to people via bird feces •unusual people to people • not a pandemic (global) human flu
• 115 human deaths (1/04-5/06) – SE Asia
Human Flu: 36,000 human deaths/yr – US
• Vaccines under development• Antiviral drugs available• Accelerated monitoring and
surveillance• Advanced diagnostic
technologies• Advanced information delivery
technologies
Causative AgentCaused by influenza strain A virus•Over 144 subtypes of type HN
•by combinations of H and N• H = Hemaglutinin• N = Neuraminidase
•examples = H1N2, H2N2, H7N2
• Types H5 and H7• mutates from LPAI to HPAI• FAD (not in US)
• Subtype H5N1 (epidemics)• HPAI• bird to bird, rarely to people• Asia
• Subtype H7N7 (epidemics)• HPAI • bird to bird, rarely to people• The Netherlands
• Various Subtypes of HN (endemics)• LPAI• bird to bird, not to people• US
Bird - bird direct contact• Feces
– fecal to oral transmission most common
• Saliva• Nasal excretions
Bird – environment - bird indirect contact:
• Mechanical contamination• Environmental transmission
– Manure – Equipment– Vehicles– Egg flats– Crates – People articles
DiagnosisLPAI• No symptoms• Low-risk virus
HPAI• Symptoms• Sudden death before symptoms• High-risk virus
– virulent– highly infectious– respiratory disease
Symptoms:• Sudden death• Lack
energy/appetite• Decreased egg
production• Egg deformities• Swellings
• Red and purple skin• Nasal discharge• Coughing/sneezing• Incoordination• Diarrhea
Prevention
BIOSECURITY!• Lock houses• Special clothing• Don’t visit other
houses• Control visitors• Cleanliness
• Submit sick birds• Dispose of dead birds• Restricted area signs• No live-bird market
birds• Sanitary/disinfectant
protocols
Regulation and Eradication
•Texas FEAD Response Plan– identify positive animals and destroy– reduce amount of time to get back test
results– track origin of suspect animals
•LPAI– quarantine– may destroy birds (depopulation) with
evidence of mutation– disinfect premises
•HPAI– quarantine– destroy birds (depopulation)– disinfect premises
Previously known as Velogenic Viscerotropic Newcastle Disease (VVND)
– Viral disease
– Affects all bird species
– Highly contagious
– Most infectious poultry disease
– Reportable
– Zoonotic
Exotic Newcastle Disease
Transmission• Virus excreted by
– Feces– Nose– Mouth – Eyes
• Virus enters by– Ingestion– Inhalation
• Spread by:– Direct contact– Mechanical means– Human contamination
• Incubation period is 2 to15 days
• Highly contagious in all bird species
• Some birds die without symptoms
Diagnosis• Clinical signs include:
– Respiratory– Digestive– Nervous– Egg production– Swelling– Death – if flocks are not vaccinated,
death rate will be 100% if animals become infected
• Maintain biosecurity measures
• No pet birds
• Diseased birds to diagnostic
lab
• Know health status of birds before bringing them to farm
Prevention
Regulation and Eradication
• Texas FEAD Emergency Response Plan
– identify positive animals and destroy
– reduce amount of time to get back
test results
– track origin of suspect animals
#1 response procedure is to destroy an infected flock and impose a strict quarantine.
• Clean entire premises
• Wait 30 days before repopulating
• Control insect/rodent population
• Deactivate virus by:– Sun exposure (UV rays)– Rapid dehydration
The virus can survive for weeks in warm, humid environments and indefinitely on frozen material.
Poultry Biosecurity• Keep Your Distance• Keep It Clean • Don’t Haul Disease Home • Don’t Borrow Disease
From Your Neighbor • Know the Warning Signs of
Infectious Bird Diseases • Report Sick Birds