Assessing climate vulnerabilities and adaptive strategies for resilient beef and dairy operations in the tropics

Cattle ranchers and dairy farmers operating throughout many tropical regions are experiencing major challenges associated with climate change such as higher incidence of heat stress and drought. These effects can result in reduced productivity of rangeland, shortage of nutritional feed, increased heat stress on animals, and high energy costs for cooling. High temperatures and resultant heat stress reduce animal productivity and increase the proliferation and survival of parasites and disease pathogens. Warming reduces the ability of dairy cattle to produce milk and gain weight and can also lower conception rates. This paper reviews research from the Caribbean on heat tolerant traits in bovine and presents evidence that introducing a slick hair gene into Holstein cows by crossbreeding with Senepols may increase thermo-tolerance and productivity. As in other parts of the tropics, principal cattle breeds in Puerto Rico and the US Virgin Islands have been largely introduced from temperate regions. Research indicates these animals may be poorly adapted to rising temperatures, leaving them increasingly vulnerable to chronic heat stress and reduced productivity. Adaptive practices have been developed in breeding and pasture management programs including selection for more heat-resistant genotypes, silvopasturing and crop diversification in forage production, and optimizing facilities and practices to reduce heat stress. Given the nature of climate vulnerability, an integrated approach to adaptation will likely have the greatest success in reducing future risk for producers.