(CNN) -- The Humane Society of the United States released Thursday what it says is video showing gruesome images of many dead chickens -- and in some cases, mummified chicken carcasses -- at a farm in southeastern Pennsylvania.
The animal protection organization says the video is from an undercover investigation it conducted at Kreider Farms in Manheim, Pennsylvania, in February and March.
Kreider Farms, on its website, describes itself as "a real working farm supplying fresh quality eggs, milk, drinks and premium batch-churned ice cream to select wholesalers and retail stores."
The video, played in a news conference, showed dead chickens in cramped cages surrounded by live chickens and eggs. Many of the birds appeared to be trapped either in cage wire or in automated feeding machinery.
"During the investigation, thousands of birds died of dehydration when there was a water system malfunction that people didn't notice for two or three days," said Paul Shapiro, vice president of the Humane Society of the United States. "Hen's legs and wings and more were found stuck inside of the wires of the cages, trapping these animals, preventing them from gaining access to food or water. Some of the floors in these barns were so packed with dead flies that our investigator described the experience as similar to walking on top of Rice Krispies."
But Kreider Farms President and CEO Ron Kreider issued a statement disputing the Humane Society's claims.
"The allegations by HSUS are a gross distortion of Kreider Farms, our employees and the way we care for our birds," the statement read. "There are still many unanswered questions regarding how and when this video was shot, edited and assembled."
The Humane Society is pushing for passage of a bill currently in the House of Representatives that it says would lead to a friendlier system of egg production. The bill is supported by the United Egg Producers, which represents farmers responsible for more than 80% of the country's egg production.
Other influential food-industry organizations, however, are opposed to the legislation. The National Pork Producers Council, for example, issued a news release in January calling it a "farm takeover bill," and saying "it would set a 'dangerous precedent' for allowing the federal government to regulate on-farm production practices, including animal housing."
The bill calls for an increase in the size of chicken cages, with the aim of preventing cramped and unsanitary conditions in which chickens lay eggs. The law would be phased in over an extended period to give farms time to make the necessary changes.
It is unclear when the House might take up the bill for consideration.
Kreider said in his statement Kreider Farms supports such legislation and asserted that more than 80% of the chickens there are already housed in new, larger, state-of-the art facilities.
Still, Shapiro said the conditions on farms such as Kreider's aren't acceptable and threaten the health of people.
"There is a direct connection many times between how we treat animals and problems that we cause for ourselves," he said. "Oftentimes when we abuse farm animals, we're not doing ourselves any favors in the process.
"There's a clear case to be made, for example, that increasing the amount of birds who are cramming in together, giving them less and less space, increases the risk of salmonella infection. In fact, at Kreider Farms we saw they were testing positive for salmonella at this facility. And so it's important to recognize that, of course, the cruelty to animals by itself is extraordinarily problematic, but there's also a consumer safety aspect to this."