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Heat stress can cause permanent production losses

An animal science professor says heat stressed dry cows can have long-term negative impacts on dairy herds.

Speaking with Brownfield at World Dairy Expo, Geoff Dahl with the University of Florida says heat stress can cause dramatic effects on a dry cow’s productivity in the following lactation, but the greatest impact is to her calf.  “When she’s heat stressed, that animal ends up being less likely to make it through her first year of life on the farm, less likely to become a productive cow on the farm and produces a lot less milk than the calf that’s dam was cooled during the dry period.”

He says heat stress starts in dairy animals at a humidity index of 68 degrees and above, and monitoring respiration rates is an easy way to determine if animals are heat stressed. Dahl says while the effects to the calf may be permanent, farmers can cool cows by using fans, soakers, shade and sand bedding.

AUDIO: Interview with Jeff Dahl