It only takes one commercial egg laying facility to be faced with the need for mass disposal to initiate a hunt for answers, but Dr. Paul Patterson, Professor of Poultry Science and Extension Specialist at Penn State University, and his team are working hard behind the scenes to provide a solution fit for the industry before it is needed by the masses.
The project is called "Ensiling Poultry Carcasses For Biosecure Preservation and Virus Destruction" and it is based on trying to meet guidelines in the United State Department of Agriculture's Foreign Animal Disease Preparedness & Response Plan, which indicates that should euthanasia exceed disposal that storage should:
Based upon Patterson's previous research he knew that hatchery waste and hen mortalities could be safely stored and recycled with fermentation. So, he designed a new study to look at using "Ag Bags," or long, thick plastic bags often used to store dairy silage, as a storage and treatment procedure for mortalities from catastrophic events like, HPAI and Newcastle-Brochitis virus. He was able to incorporate 20,000 lbs. or 10 tons of carcasses and carbohydrate sources into a six-foot diameter bag that was 20 feet long. He used two different carbohydrate treatments to “pickle” the carcasses: 1) 14% hen feed and 2) a mix of 9% hen feed and 5% sugar and inoculated the bags with a silage culture of bacteria P. acidilactici & L. plantarum. Eighteen carcasses inoculated with live Newcastle vaccine virus, which is a similar type virus to HPAI, were added to the bag to evaluate the treatments for their potential to destroy HPAI.
The results have been positive. There has been a rapid and sustained drop in pH, which makes it hard for organisms to survive. The bacteria samples proved the effectiveness of the pH drop as Coliforms were eliminated by day seven in the feed and sugar trial and by day fourteen on the feed only trial. Additionally, virus isolation samples were all Newcastle negative showing this approach may be effective for killing not only bacteria, but also for viruses.
While the gas generation from the bags will require management with one-way valves or another strategy, the favorable mechanics and logistics of carcass handling that meet USDA's storage guidelines indicate this is a likely tool for our larger farms. Dr. Patterson indicated, “The process can be scaled up for larger facilities.” 100,000 hens could be ensiled and stored in a ten-foot diameter bag that is 124 feet long, or hens from a one million-bird complex would fit in a 14-foot diameter bag, 630 feet long.
Patterson's co-investigators on the project included Mike Hulet, Lisa Kitto and Amy Mayer in Penn State’s Department of Animal Science and Patricia Dunn, Huaguang Lu and Subhashine Kariyawasam of in the Department of Veterinary and Biomedical Sciences.