(Adds comments from Aviagen, U.S. Department of Agriculture,
Alabama state veterinarian, background, testing process)
By Tom Polansek
CHICAGO, March 14 Aviagen, the
world's leading poultry breeding company, has euthanized
chickens at a farm in Alabama over concerns about bird flu, the
company said on Tuesday, as likely cases of the disease emerged
in a top chicken-producing state.
Alabama officials said they suspected that poultry at three
sites in the state were infected with the virus, about a week
after some 90,500 chickens were culled over infections at two
commercial operations across the border in Tennessee.
Aviagen detected the presence of antibodies for the flu
virus in a flock in Alabama that showed "no evidence of clinical
disease," company spokeswoman Marla Robinson said in an email.
The company is based in Alabama.
The company euthanized the flock and "all eggs which were
collected from that farm in the production system were traced
and removed," she said. Aviagen did not respond to a question
about how many birds were killed.
Tony Frazier, Alabama's state veterinarian, said the company
chose to cull about 15,000 birds. The U.S. Department of
Agriculture (USDA) said the farm had 153,000 birds.
A national USDA lab is testing samples from poultry in
Alabama to identify the strain of the virus and how lethal it is
for birds, after another agency-approved lab identified the H7
subtype of the disease in samples, USDA spokeswoman Lyndsay Cole
The birds in Alabama did not show clinical signs of
sickness, which indicates they did not have a highly lethal, or
pathogenic, form of the virus, Cole said.
In Tennessee, both cases were identified as H7N9. The USDA
on March 5 confirmed that one was the United States' first
infection of highly pathogenic flu in commercial poultry in a
year. Days later, the state said it had found the other case
nearby and it was low pathogenic.
Highly pathogenic bird flu led to the deaths of about 50
million birds, mostly egg-laying hens, in the United States in
2014 and 2015.
Another highly pathogenic outbreak would likely represent a
financial blow for poultry operators such as Tyson Foods Inc
and Pilgrim's Pride Corp because it would kill
more birds or require flocks to be culled.
It also would likely trigger more import bans from trading
partners, after South Korea, Japan and other countries limited
imports after the highly pathogenic case in Tennessee.
Health officials have said the risk of bird flu spreading to
people from poultry or making food unsafe was low.
Separately, Frazier said the owner of a backyard flock
suspected of having the virus chose to cull about 70 birds. No
poultry linked to the third suspected case, which involved birds
at a flea market, have been culled, he said.
Frazier said the cases were still only suspected flu
infections and needed to be confirmed by the USDA. Earlier, the
Alabama Department of Agriculture and Industries called a news
conference to discuss what it said were three findings of avian
Alabama raised more than 1 billion chickens for meat in
2015, making it the country's third largest producer, according
to the USDA.
The national USDA laboratory, to which samples from the
state were sent, is the only one in the United States that
officially confirms cases.
The World Organization for Animal Health requires that all
confirmed low-pathogenic H5 and H7 bird flu subtypes be reported
because of their potential to mutate into highly pathogenic
strains. Highly pathogenic cases also must be reported.
(Reporting by Tom Polansek; Editing by Frances Kerry, Toni