By Blake Jackson
A recent study has revealed that rising temperatures are affecting dairy farming in more ways than previously understood. Heat stress not only reduces the amount of milk cows produce but also lowers its quality by decreasing fat and protein content.
The research, published in Environmental Research Letters, analyzed data from 2007 to 2016 covering around 6.5 million dairy cows across 43 U.S. states. Scientists compared milk production records with weather data to understand how heat and humidity impact cows.
“The heat-induced dilution of these valuable milk components is happening a bit under the radar,” said senior author Ariel Ortiz-Bobea. “When you account for the deterioration in milk composition, the economic loss ends up being of the same order of magnitude as the yield effect, so it just basically doubles the damage.”
The study found that milk yield drops sharply when temperatures pass certain heat and humidity levels. However, the quality of milk begins to decline even at lower temperatures. This means cows are affected by heat stress more often than farmers may notice.
Researchers estimate that an increase of 10 points in the temperature-humidity index leads to a 1.2 percent drop in milk production and a 2.8 percent reduction in farmer income. This equals an annual loss of about $1.65 billion in the dairy industry.
“It’s another headwind for dairy farmers,” Ortiz-Bobea said. “Milk prices are low, and farmers are struggling, and that usually leads to more consolidation, which changes the landscape in rural areas, literally and economically.”
The study also found limited evidence that cows are adapting to higher temperatures. The main adaptation has been where farms are located, with cooler regions like New York and Wisconsin having more dairy farms.
Researchers believe future efforts should focus on breeding cows that can better handle heat. They also hope to use more detailed data to identify heat-resistant animals.
This study highlights the growing impact of climate change on agriculture and the need for better strategies to protect dairy farming.
Photo Credit: gettyimages-vm
Categories: New York, Livestock, Dairy Cattle, Weather