Officials used the “last resort” method of turning off the ventilation system to kill chickens and turkeys in their barns while eradicating an avian influenza outbreak in southwestern Indiana last week. It was the first time the approach, an emergency measure in the USDA’s view, has been used against bird flu. The Humane Society of the United States says, “This method involves essentially baking birds to death over a period of time which can last hours and involves intense suffering.” The usual methods for killing flocks are to bury them in a liquid foam or pump carbon dioxide gas into poultry barns. The Indiana Board of Animal Health said water valves and hoses froze in cold weather, making it difficult to use the water-based foam, said the Jeffersonville News and Tribune.
USDA officials said in its bird flu plan last fall that ventilation shutdowns could be used when it was essential to kill a large number of fowl quickly and the standard methods would be too slow. “Depopulation within 24 hours of an HPAI (highly pathogenic avian influenza) diagnosis is ideal to reduce the risk of disease spread,” says the master plan. “While not a preferred method, it [ventilation shutdown] could save the lives of thousands of birds by reducing the risk of disease spread.” In Indiana, more than 400,000 birds were destroyed to prevent the spread of bird flu. The HSUS said ventilation shutdown “should only be considered as an absolute last resort, and not the first response to an outbreak.”
Indiana state veterinarian Brett Marsh said the USDA approved closure of ventilation systems at the 10 farms were bird flu was confirmed or suspected, according to the Associated Press. Ventilation shutdown was used to kill 156,000 chickens and some of the turkey flocks, said AP.
The USDA updated several points of its response plan for avian influenza at the close of last week. As part of the update, the agency said it would pay a flat rate to producers — $1.15 per broiler, $3.55 per turkey and $6.45 per laying hen — to cover the cost of cleaning and decontaminating barns after a bird-flu case. The agency also recommended additional preparedness steps, such as greater use of premises IDs.
In addition, the USDA said it will not pay the cost of administering bird-flu vaccine, if it authorizes use of a vaccine. The government is stockpiling millions of doses of vaccine. And the agency said it may rule against giving vaccine to some birds, such as broiler chickens that ordinarily go reach market size quickly.