Author : Sabutan, Manuel G.

Summary : The study evaluated the growth performance, mainly weaning weights, of F (subscript 1)-50 percent Grade Nellore x 50 percent American Brahman, F (subscript 2)-25 percent Grade Nellore x 75 percent American Brahman, F (subscript 3)-12.5 percent Grade Nellore x 87.5 percent American Brahman and Pb 100 percent American Brahman. The study was conducted in South Cotabato, Philippines using 657 records from 1972 to 1978, inclusive. The weaning weight data were adjusted at 205-days weaning age and the least-squares method was used for its statistical analysis. The statistical analysis showed that the 205-day adjusted weaning weights for F (subscript 1), F (subscript 2), F (subsript 3), and Pb were 151.0, 154.8, 155.6, and 164.5 kg, respectively, and the overall adjusted weaning weight was 159.52 kg. Purebred American Brahman calves were 13.5 and 9.7 kg significantly (P<.01) heavier than F (subscript 1) and F (subscript 2) calves, respectively, but was not statistically (P>.05) different from weights of F (subscript 3) calves at weaning. The overall weaning weights mean for male calves was 159.5 kg. The observed means at weaning were: 151.4, 159.0, 157.2, and 170.3 kg for F (subscript 1), F (subscript 2), F (subscript 3), and Pb male calves, respectively. Differences for the purebred American Brahman male calves were 18.9 and 11.3 kg significantly (P<.01) heavier than F (subscript 1) and F (subscript 2) male calves, respectively, but statistically similar to the weaning weight of F (subscript 3) animals. The F (subscript 2) male calves were slightly heavier than F (subscript 1) and F (subscript 3). However, these differences were not statistically (P>.05) significant. The overall mean at weaning for the female calves was 153.1 kg. The observed weaning weight means were 150.5, 148.7, 155.0, and 158.2 kg for F (subscript 1), F (subscript 2), F (subscript 3), and Pb female calves, respectively. Purebred American Brahman female calves were 7.7 and 9.5 kg statistically (P<.01) heavier than F (subscript 1) and F (subscript 2) calves, respectively, and had 3.2 kg advantage over that of F (subscript 3) animals, but, this difference was not statistically (P>.05) significant. The F (subscript 1), F (subscript 2), and F (subscript 3) calves were statistically similar. Year effects were significant (P<.10) source of variation on weights of calves at weaning. Generally, the group average weaning weight means reduced tremendously (168.4 to 153.2 kg) from 1974 to 1977, but substantially increased (160.9 kg) in 1978. Average weights at weaning for F (subscript 1), F (subscript 2), and F (subscript 3) calves were statistically (P<.05) similar. On the other hand, Pb was heavier (P<.01) than F (subscript 1) and F (subscript 2), but statistically similar to F (subscript 3) animals. An increasing trend of weaning weight was noted as Brahman blood increased.