Unlocking Genetic Heat Tolerance in Cattle

Importance of Breakthrough

When subject to high temperatures, most cattle breeds in the U.S. often undergo stress causing them to exhibit extreme physical reactions. Heat stress reduces feed intake, impedes growth and increases disease susceptibility; ultimately, heat stress decreases milk and meat production per amount of greenhouse gas emitted.

Details about this breakthrough

To address this problem, Acceligen researchers designed genetic modifications to render cattle more resistant to heat. These modifications were based on Acceligen’s previous research of the prolactin receptor gene found in cattle breeds adapted to the heat of the Caribbean Basin. Using new breeding technologies based on gene editing, researchers introduced a genetic modification in the prolactin receptor that led to a condition known as SLICK, which protects these animals from heat stress. Cows with a SLICK mutation also have lower normal body temperatures than cattle without it and shorter hair that allows their bodies to respond more efficiently as temperatures rise.

This research provides opportunities to control heat stress, making breeds of elite performance genetics more productive in areas experiencing warmer temperatures. The SLICK mutation, which reduces animal stress caused by lack of heat tolerance, can improve animal health, well-being and fertility. More healthy and productive herds could further meet the growing demands for beef and dairy in geographies where sustainable production of local animal protein has been challenging. The SLICK animals produced in this project by Acceligen are under regulatory review in multiple countries, which will allow the semen to be commercialized in the U.S. and abroad in economies with tropical production zones. In addition to delivering precision-bred adapted cattle, the researchers generated three large sets of RNA sequencing data, which are freely available through the Gene Expression Omnibus of the National Center for Biotechnology Information.