‘A Lot of Work to Do’
Aspects of poultry welfare are garnering a great deal of focus, especially in relation to production practices for laying hens and broiler chickens. Yvonne Vizzier Thaxton, DVM and retired director of the Center for Food Animal Wellbeing at the Univ. of Arkansas, says the poultry industry has come a long way in recent years, but in the spirit of continuous improvement notes, “No system is perfect. We’ve got a lot of work to do.”
In a 2016 paper, she co-authored in the Poultry Journal titled, “Animal Welfare Challenges for Today and Tomorrow,” Thaxton cited some of the challenges in the poultry industry.
“For broiler chickens, increases in the growth rate and housing concerns dominate the list of items for continuing improvement. Stocking densities, lighting programs, muscle myopathies, and use of antibiotics are also areas that require research attention.
“In the egg layer industry, the key challenge is housing, with the industry undergoing a shift from conventional cage housing to alternatives like enriched colonies or cage free housing. While these alternative systems have hen welfare advantages, there are also welfare disadvantages, and it is also essential to address associated issues including economic, environmental, egg safety, and worker health impacts.”
Matt Prescott, senior director of Food Policy for HSUS, acknowledges the recent progress made by the meat industry, and also sees elements of poultry welfare as the next big challenge on the table: “Probably the biggest thing going on in this space right now is, for the very first time, major companies requiring substantial welfare improvements from their chicken suppliers. Rising to meet this growing demand,” he continues, “and getting out in front of it, for better breeding, housing and slaughtering practices is a great topic.”
CO2 Stunning for Hogs
Kurt Vogel, the Kraft/Oscar Mayer faculty scholar at the Univ. of Wisconsin-River Falls, points to the CO2 stunning of hogs as an important area to continue to work on.
“I think we need to keep working on how animals respond to controlled atmosphere stunning systems,” he says. “In particular, we’ve really got to look at what’s going on in the pit for CO2 stunning systems for hogs. To a large extent we don’t know what their behavior looks like when they dip down into the pit. There are pigs that respond aversely to CO2, and they’ll display escape behavior when they go into the pit, and that’s an indication that they’re experiencing distress during that process.
“I think genetics could be a significant piece of the puzzle; in humans, some people will react very aversely to CO2 exposure, high dose because it burns, whereas other people won’t pick it up.”
Vogel says other gases besides CO2 need to be examined. “One of the things we need to continue to explore is the use of gas blends, where gases besides CO2 may be more inert for the animal.”
Mass Euthanasia
Individual euthanasia in production systems is normally handled in a slaughter plant’s animal welfare program. This includes, for example, a cow or pig that is injured or sick that doesn’t pass ante-mortem inspection.
In the 2015 avian influenza outbreak, flocks of laying hens numbering in the millions were depopulated, bringing focus to the challenge of mass euthanasia. Depopulation methods include mass suffocation and death by heat stress, which are neither quick nor painless.
“Our current methods of mass euthanasia for houses of laying hens is not as humane as it could be,” says Candace Croney, Ph.D., the director of the Center for Animal Welfare Science at Purdue Univ. “The process takes a long time and the methodology can cause significant distress to the animals in the process. Right now nobody has a good answer to that question.”
Thaxton reiterates that it’s definitely an area that needs a solution. “Further research is needed on more rapid, humane, on-farm depopulation methods.”
