Research Pinpoints Why Dairy Cows Produce Less Milk in Warm Weather and Develops Nutrition-Based Solution



  • Advanced Animal Systems

man and woman kneeling in front of cow in dairy barn stall with woman stretching out her hand to feed the cow silage

Breakthrough Could Revolutionize Dairy Cattle

A new Cornell-led study funded by a Foundation for Food & Agriculture Research (FFAR) Seeding Solutions grant has found a nutrition-based solution to restore milk production in heat-stressed cows, while also pinpointing the cause of the decline. This study’s breakthroughs will inform further research that could reveal how different feed additives or changes to the staple diet of cows across the U.S. can sustainably increase milk production, even as temperatures continue to climb. Currently, sprinklers and fans are the primary ways used to mitigate heat stress on cows, but these strategies consume water, burn fossil fuels and only restore about 60% of milk production.

Heat-Stressed Dairy Cows Develop “Leaky Gut”

It was previously known that heat stress causes cows to eat less, accounting for 30-50% of the drop in milk production. The study, published August 2, 2022, in the Journal of Dairy Science, demonstrated that the remaining decline in milk production in heat-stressed dairy cows is caused by increased gut permeability, or “leaky gut.” Occurring in as little as three days, the condition is caused by bacteria and other material “leaking” through weakened parts of the intestinal wall.

In this study, researchers also found that milk production can be partially restored by feeding the cows organic acids and pure botanicals, which normalized gut permeability and increased feed intake and milk production, restoring about three kilograms of milk per day. The cows also exhibited evidence of increased nitrogen-use efficiency, which means less nitrogen – a potential climate pollutant – is excreted into the environment.

This study has immediate application. If we can understand the nutrient requirements that a cow has during a heat-stress event, we could revolutionize the dairy cattle industry by ensuring she's getting what she needs to maintain optimum health and performance. Dr. Joseph McFadden
Associate Professor of dairy cattle biology in the Cornell College of Agriculture and Life Sciences and senior author of the study

FFAR Fellows Program Assists with Research

Ananda Fontoura, a doctoral student in McFadden’s lab and a 2018-2021 FFAR Fellows Program, is assisting in this research and is the study’s first author. Learn more about how her research assistance is impacting the dairy cow industry.

Climate change and Dairy Farming: Beating the Heat

More About This Research

The study, published August 2, 2022, in the Journal of Dairy Science, can be found here.  

Our $736,392 investment in this research is part of our Seeding Solutions annual competitive grant program that supports bold research in any of our six Challenge Areas or AgMission.

Learn more about other FFAR-funded research breakthroughs.



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