Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2004
Publication Date: 6/1/2004
Citation: Chase, C.C., Riley, D.G., Olson, T.A., Coleman, S.W., Hammond, A.C. 2004. Maternal and reproductive performance of brahman x angus, senepol x angus, and tuli x angus cows in the subtropics. Journal of Animal Science: Vol.82, pp. 2764- 2772. Interpretive Summary: In the hot-humid subtropics of the United States, the beef cattle industry is largely cow-calf. Generally, calves produced in this region are transported to the mid-west for growing and finishing. This necessitates that the cows are adapted to the region. Brahman (Zebu) crossbred cows are dominant in this region because they combine the adaptation of the Brahman with the more desirable carcass qualities, earlier maturity, and reproductive efficiency of breeds adapted to temperate climates. Recently, emphasis has been placed on the adaptability and productivity of tropically adapted non-Zebu breeds. The objective of this study was to evaluate the performance of Brahman x Angus, Senepol x Angus, and Tuli x Angus cows in the subtropics of Central Florida. The Senepol is an adapted non-Zebu breed from U.S. Virgin Islands and the Tuli is an adapted Sanga breed from Zimbabwe. Forty-two Brahman x Angus, 34 Senepol x Angus, and 50 Tuli x Angus cows were mated to Angus bulls for their first calf and to Charolais bulls for their subsequent calves. Weaning weights of calves from Charolais bulls and Brahman x Angus cows were the heaviest, Tuli x Angus cows the lightest, and Senepol x Angus cows was intermediate. Weaning weight is an important criteria because most beef cattle producers market their calves based on weight around the time of weaning. The percentage of cows that calved and weaned a calf each year are important production criteria, and were lowest for Senepol x Angus cows and did not differ between Brahman x Angus and Tuli x Angus cows. Tuli x Angus cows tended to have more difficult births and fewer calves survived to weaning than did Brahman x Angus cows. When the weaning weight of calves was divided by the number of cows presented or exposed to the Charolais bulls, the weight for Brahman x Angus cows was greatest, Senepol x Angus cows was least, and Tuli x Angus cows was intermediate. Another consideration is cow weight, and Brahman x Angus were the heaviest, Tuli x Angus the lightest and Senepol x Angus intermediate. If weaning weight of calves is divided by the weights of cows exposed the efficiency of the Brahman x Angus and Tuli x Angus cows are quite similar. Producers in warm regions should consider that performance of Tuli x Angus cows, but not Senepol x Angus cows, was comparable to Brahman x Angus cows except for lower calf survival from birth to weaning and weaning weight.
Technical Abstract: To determine the maternal and reproductive performance of adapted F1 cows in the subtropics, 42 Brahman x Angus, 34 Senepol x Angus, and 50 Tuli x Angus cows were bred to Angus bulls to calve first and subsequently to Charolais bulls to calve as three- to eight-yr-olds. Age at first calving did not differ among crossbred cows. Angus-sired calf birth weights were heavier (P < 0.01) from Senepol x Angus than either Brahman x Angus or Tuli x Angus cows. Weaning weights of Angus-sired calves were heavier (P < 0.01) from Brahman x Angus (213.5 kg) than either Senepol x Angus (194.9 kg) or Tuli x Angus (191.5 kg) cows. As three- to eight-yr-old cows, calf birth weights were heavier (P < 0.05) from Senepol x Angus compared to Brahman x Angus but not Tuli x Angus cows. Weaning weights of Charolais-sired calves were heaviest (P < 0.05) from Brahman x Angus cows (268.9 kg), lightest from Tuli x Angus cows (233.4 kg), and intermediate from Senepol x Angus cows (245.0 kg). Calf crop born and calf crop weaned were lowest (P < 0.05) for Senepol x Angus cows (76.9 and 70.2%) and did not differ between Brahman x Angus (89.0 and 86.1%) and Tuli x Angus (94.7 and 86.5%) cows. Tuli x Angus cows tended (P < 0.10) to have a lower percentage of normal births and lower (P < 0.10) calf survival to weaning than Brahman x Angus cows but not Senepol x Angus cows. As three- to eight-yr-olds, weaning weight per cow exposed was heaviest (P < 0.05) for Brahman x Angus (234.2 kg), lightest (P < 0.05) for Senepol x Angus (173.0 kg), and intermediate (P < 0.05) for Tuli x Angus (209.1 kg) cows. Efficiency, weaning weight per 100 kg cow exposed, was similar for Brahman x Angus (45.0) and Tuli x Angus (44.2) cows and both were greater (P < 0.01) than for Senepol x Angus (37.6) cows. These data indicate that in the subtropics, maternal and reproductive performance of Tuli x Angus cows, but not Senepol x Angus cows, was comparable to Brahman x Angus cows except for lower calf survivability and weaning weight.