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Foreign Animal Diseases in Poultry Angie Dement Extension Associate for Veterinary Medicine Texas AgriLife Extension Service The Texas A&M System http://aevm.tamu.edu Improving Lives. Improving Texas. “Avian Flu” “Bird Flu” Viral disease Two 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 Affects many bird species: • Chickens • Turkeys • Pheasants • Quail • Geese • Ducks • Guinea fowl Causative Agent Caused 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 Virus denatured by: • Heat – Proper cooking • Drying • Most disinfectants/detergents Transmission Natural reservoir: • Migratory waterfowl • Virus in intestines • Virus shed in feces “One gram of contaminated manure can contain enough virus to infect 1 million birds.” 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 Diagnosis LPAI • • 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 Exotic Newcastle Disease Previously known as Velogenic Viscerotropic Newcastle Disease (VVND) – Viral disease – Affects all bird species – Highly contagious – Most infectious poultry disease – Reportable – Zoonotic Causative Agent • Virus – Serotype group Avian paramyxovirus type 1 (APMV-1) • Highly resilient 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 Prevention • Maintain biosecurity measures • No pet birds • Diseased birds to diagnostic lab • Know health status of birds before bringing them to farm 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 Questions