Cattle eat less when it is hot

November 2024

When cattle are too hot, they tend to stop eating, said Raluca Mateescu, a professor in the Department of Animal Science at the University of Florida’s Institute of Food and Agricultural Sciences. This affects the cattle’s health and growth and threatens the longevity of the food supply coming from that herd.

Climate change is making it more difficult to raise cattle – growth and reproduction are affected by heat – so it’s critical to breed cattle that are better adapted to a hotter and longer summer. She explained that cows eliminate about 85% of their body heat via sweat.

According to prof. Mateescu, heat stress in subtropical regions, which are the areas just north and south of the topics and generally considered the hottest in the world, is such a significant limiting factor that about 9 million of beef production is lost annually due to reduced performance nationally.

A new study from this department published in the Journal of Animal Science and Biotechnology shows it’s possible to identify the genes within cattle breeds that would lead to the sweatiest, most heat-tolerant offspring.

The study found that there is significant variation between cows of the same breed – in this case, Brangus, which is a cross between Brahman and Angus. (The study looked at 2 401 Brangus cattle from two commercial ranches in Florida.)

Being able to select cattle to breed based on their sweating ability could lead to herds that can tolerate hotter climates and still grow and reproduce.

Skin biopsies helped the researchers to determine the phenotypes that contributed to the animals’ ability to manage heat stress, such as the sweat-gland area, depth and length. Scientists genotyped all animals and used software to estimate genetic parameters.

The study found that a moderate amount of variation in sweating ability is genetic, so farmers could select sweatier cattle based on genetic markers. It found that genetics from both the Brahman and Angus genes positively contribute to the sweating ability in Brangus cattle.

Source: https://www.sciencedaily.com/releases/2024/06/240613221915.htm

Publication: November 2024

Section: Pula/Imvula

Author: RPO Newsletter, 5 September