Matthew J. Salois, chief economist for the American Veterinary Medical Association (AVMA), presented to the New York Academy of Sciences on the implications of raising animals without antibiotics. The presentation, “Sustainability and Antimicrobial Use in Animal Agriculture,” calls for nuanced and evidence-based antibiotic policies that consider a holistic view of antibiotics’ impacts on animal welfare, the environment, and economics.
In recent years, some companies and consumers have embraced raising animals without antibiotics; today, nearly half of all broiler chickens are raised without antibiotics, according to the AVMA.
During his presentation, Dr. Salois cautioned that reduced use of antibiotics in farm animals can have negative implications for animal welfare and the overall sustainability of animal agriculture, if not accompanied by appropriate changes in management practices.
For example, the average mortality rate for broiler chickens raised without antibiotics can be 25 to 50 percent higher than for conventionally raised broiler chickens, he said. Additionally, birds raised without antibiotics are much more likely to suffer from painful medical conditions, such as being more than three times as likely to experience ammonia burns in their eyes, Salois added.
The higher incidences of disease and mortality for birds raised without antibiotics, coupled with slower growth, means that more than 680 million additional birds will need to be raised annually to meet poultry demand in the U.S., Salois said. This increase consumes significant environmental resources, including more than 1.9 billion additional gallons of water and more than 5.4 million additional tons of feed per year, he added.
While broiler flocks raised without antibiotics have on average higher mortality rates than flocks for which access to antibiotics is allowed, the mortality gap has been closing over time, according to Salois’ findings. This can be attributed, in part, to poultry producers and veterinarians having learned a great deal over the last few years about how to better manage flocks that are raised without antibiotics, such as decreasing stocking density and increasing flock cycle downtime, he said, adding that access to alternatives including vaccines, probiotics, and enzymes has reduced antibiotic use in general.
Salois said these findings indicate the need for a thoughtful, data-driven approach to antibiotic use that considers a broad range of issues and seeks to balance animal welfare and environmental and economic outcomes.