Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: December 18, 2004
Publication Date: February 8, 2005
Citation: Chase, C.C., Riley, D.G., Olson, T.A., Coleman, S.W. 2005. Evaluation of brahman and tropically adapted bos taurus breeds in the humid subtropics. Journal of Animal Science. 83(Suppl. 2):27.
Classic studies conducted in the 1960s between Brooksville, Florida and Miles City, Montana clearly established the presence of genotype by environment interactions. Those researchers concluded that the advantages of local over introduced lines were large enough to be of great economic significance in commercial beef production. Matching cow type to the environment in which she is asked to perform is an important consideration particularly in harsh climates. Environment, however, is not simply related to geography or climate but also includes nutrition, disease, and pest prevalence. Brahman cows of small, medium, and large frame sizes were bred to like frame size bulls. Weaning rate was considerably lower for large frame size first-parity and second-parity dams compared to small and medium frame size dams. This was due to poor calf survivability for large frame size first-parity dams and to low conception for large frame size second-parity dams. Weaning rates did not differ among frame sizes in third or greater-parity dams. Although the Brahman is undoubtedly adapted to the tropics there are tropically adapted Bos taurus breeds that may offer other attributes for southern US cattle production. In crossbreeding studies between Senepol and Hereford, significant levels of heterosis were observed for preweaning calf performance and feedlot performance of steers. Breedtypes did not differ for USDA yield and quality grades or Warner Bratzler shear force. A more recent study evaluated maternal and reproductive performance of Brahman x Angus, Senepol x Angus, and Tuli x Angus cows. Tuli x Angus cows had similar calf crop born and weaned as Brahman x Angus cows. Reproductive and maternal performance of Tuli x Angus cows were comparable to Brahman x Angus cows except for calf weaning weight and some calving difficulty. Most recent studies have evaluated the Romosinuano, a tropically adapted Bos taurus breed native to Colombia. Earlier studies showed that Romosinuano bulls and heifers reach puberty at relatively young ages similar to Angus. Currently a diallel breeding scheme among Angus, Brahman, and Romosinuano is being conducted.