Bird Flu Outbreaks in U.S. Dairy Cow Herds Spark Concerns Over Contaminated Poultry Litter as Feed Source

Recent bird flu outbreaks affecting dairy cow herds across nine U.S. states have raised questions regarding the potential role of contaminated poultry litter in transmitting the virus.

Poultry litter, a mixture of chicken feces, feathers, and bedding materials, is commonly used as both a fertilizer and feed for cattle.

While some states like California prohibit the use of poultry litter as feed for lactating dairy cows, its usage in other types of cattle remains permitted.

Studies have indicated that chicken litter can harbor harmful bacteria, leading to concerns that it may also carry traces of the bird flu virus.

However, experts emphasize that more information is needed to determine the link between poultry litter and the recent outbreaks in dairy cows.

Jodie Guest, a senior figure at Emory University‘s Rollins School of Public Health, highlighted the importance of understanding the extent to which dairy herds are fed poultry litter before drawing conclusions.

The U.S. Department of Agriculture has pointed to wild migratory birds as the primary source of the outbreaks, while also acknowledging the potential for cow-to-cow transmission through infected unpasteurized milk.

The use of poultry litter as cattle feed is often motivated by its cost-effectiveness and its dual purpose in waste disposal, according to the Department of Animal Sciences at the University of Missouri.

Regulatory history shows varying stances on the practice, with initial discouragement by the FDA, later rescinded and delegated to state governments.

Notably, the FDA’s restrictions on feeding poultry litter to cattle have evolved over time, particularly in response to concerns related to diseases like mad cow disease.

In other instances worldwide, bird flu has been linked to cross-species transmission through contaminated food sources, highlighting the importance of monitoring feed practices for potential disease spread.