Climate Adaptation of Tropical Cattle

Abstract

There is sustained growth in the number of tropical cattle, which represent more than half of all cattle worldwide. By and large, most research in tropical areas is still focused on breeds of cattle, their particular advantages or disadvantages in tropical areas, and the tropical forages or feeds that could be usefully fed to them. A consistent issue for adaptation to climate is the heat of tropical environments. Changing the external characteristics of the animal, such as color and coat characteristics, is one way to adapt, and there are several major genes for these traits. However, further improvement in heat tolerance and other adaptation traits will need to use the entire genome and all physical and physiological systems. Apart from the response to heat, climate forcing through methane emission identifies dry season weight loss as an important if somewhat neglected trait in climate adaptation of cattle. The use of genome-estimated breeding values in tropical areas is in its infancy and will be difficult to implement, but will be essential for rapid, coordinated genetic improvement. The difficulty of implementation cannot be exaggerated and may require major improvements in methodology.

Genetic parameters for hair characteristics and core body temperature in a multibreed Brahman–Angus herd1

“…As Brahman breed composition increased by 25%, undercoat and topcoat length decreased by 1.16 ± 0.59 mm and 2.94 ± 0.19 mm, respectively. These results support previous findings that indicine cattle have shorter, slicker hair coats than taurine cattle (Olson et al, 2003;Landaeta-Hernández et al, 2011;Barendse, 2017). Across all measurements and breed groups, hair length tended to decrease as indicine influence increased.…”

“…These economic losses are expected to increase as thermal stress increases due to climate change (Hahn, 1999;Renaudeau et al, 2012). Thermal tolerance is influenced by many factors, including breed and hair coat properties (Turner and Schleger, 1960;Jenkinson et al, 1975;Gaughan et al, 1999;Olson et al, 2003;Burrow, 2012;Porto-Neto et al, 2014;Barendse, 2017). Differences within and between breeds for thermal tolerance and hair coat properties exist and are indicative of opportunities for improvement through selection (Landaeta-Hernández et al, 2011;Hamblen et al, 2018).…”

Scans for signatures of selection in Russian cattle breed genomes reveal new candidate genes for environmental adaptation and acclimation

“…In addition, domesticated species (e.g., livestock) have been exposed to natural selection to adapt to the diverse environments into which they have been moved together with migrating human populations 8 and during natural migrations prior to domestication 9 . Domestic cattle provide a good example of a species that has been domesticated at least twice in human history 10 , that has adapted to diverse environmental conditions ranging from Africa to Siberia 11 and that has been under strong artificial selection to produce more than 1000 extant breeds 12 exhibiting diverse levels of milk production, meat quality, feed efficiency and other economically important traits 13 . The main sources of modern cattle breed genetics are two Bos subspecies: B .…”

Resilient capacity of cattle to environmental challenges – An updated review

“…Morphological adaptation includes coat color, fur depth, hair type, hair density, fat storage in hump or tail, skin color and body size (Khalifa 2003). Morphological alteration is one way of adaptation during the harsh environment (Barendse 2017). During heat stress, cattle exhibit some morphological changes, which include larger salivary glands, higher surface area of absorptive mucosa and the ability to increase the considerable volume of the foregut when fed with high fibrous food (Silanikove and Koluman 2015).…”