By Theopolis Waters June 20(Reuters) - A low-pathogenic strain of avian influenza was found on an Arkansas poultry farm, but was quickly contained and did not appear to be a threat to other poultry farms in the nation's second largest chicken state, a state poultry official said. "We're pretty certain this was isolated to just this one farm. USDA is there with us on hand as we work the next few weeks to make sure it's contained," said Arkansas Livestock and Poultry Commission director Preston Scroggin. The influenza is a milder strain of the flu that killed dozens of people in China and crippled its poultry industry. Testing found about eight birds in the Arkansas flock of 9,000 were positive for the H7N7 low-pathogen avian flu, Scroggin said. The flock was humanly euthanized and buried and the eggs they produced were destroyed. The farm and all farms within a 6.2-mile radius of it were quarantined. No additional cases were found on nearby farms. The Arkansas farm supplied birds to Tyson Foods Inc , Scroggin said. Poultry farms 30 to 40 miles away from the site sent in birds for testing and they have come back negative, he said. Scroggin said the farm is in Scott County in western Arkansas and raises hens that produce eggs for chickens. Tyson Foods, which supplied the birds and feed to the farmer who owns the facility, learned of the problem through routine testing last week. Tyson immediately notified the poultry commission, which conducted follow-up tests and sent test samples to the U.S. Department of Agriculture's lab in Ames, Iowa for confirmation. "We're working cooperatively with the USDA and the Arkansas Agriculture Department regarding a flock of breeder chickens that contracted a low pathogenic, or mild strain of avian influenza," said Tyson spokesman Gary Mickelson. Tyson has since heightened its bio-security measures and surveillance of avian influenza, said Mickelson. It also plan to test all area breeder farms that serve the company, as well as any contract broiler farms within a six mile radius of the affected farm, he said. Neither the meat or the eggs would have entered the human consumption chain. Also, the virus does not pose a threat to humans, state and industry officials said.