USDA has given its approval to a method, which involves sealing poultry in non-ventilated barns and turning up the heat, to kill birds with flu.
Animal rights activists have come down heavily on the USDA and labelled the method as cruel as the entire process takes about 30-40 minutes and bakes birds to death, reported Reuters.
The US Department of Agriculture (USDA) stated that the method will be applicable only if all other ways of killing poultry are not feasbile within 24 hours of discovering the infection.
The department termed this method as a 'necessary alternative' to kill the virus.
Nearly 50 million chickens and turkeys died from the flu between December and June, which has been the worst animal disease outbreak ever in the US.
An Iowa Farm Bureau Federation-commissioned study found that the state's egg, chicken and turkey industry had seen a loss of $800m, which is in addition to $400m loss in wages and taxes to governments.
It has been two months since the last outbreak and officials are now readying for another possible resurgence of the outbreak this fall as migratory birds tend to carry this virus.
Humane Society chief veterinary officer Michael Blackwell was quoted by Reuters as saying: "We shouldn't compound the problems for birds by subjecting them to a particularly miserable and protracted means of euthanasia."
USDA's first preferences for culling infected poultry are suffocating them with foam or put them in chambers filled with carbon dioxide,these methods have been used last spring.
This move by the USDA comes as it is trying to improve its response following several complaints from farmers for going too slow in culling infected poultry as they believe that delays can contribute to the spread of the disease.
The department has given approval to Harrisvaccines to produce a vaccine to control bird flu. This makes Harrisvaccines the first company to come with up a vaccine into the US market.
