Studies on the improvement of cheju native cattle with brahman and santa gertrudis ii. genetic and environmental effects for postweaning growth
Kim, D.C.; Kim, J.K.; Lee, H.S.; Paik, Y.K.
Korean Journal of Animal Science 29(6): 249-257
The primary objective of this breeding project was to study methods for improvement of economically important traits of Cheju Native Cattle with Brahman and Santa Gertrudis that are adaptable to specific climatic conditions, poor quality forage and to make use of some other genetic merits. Data obtained from 428 calves (59 Cheju Native Cattle, 60 Brahman, 40 Santa Gertrudis and 269 crossbreds) were analyzed to estimate main effects of environmental factors on postweaning periods. The results of this study are summarised as follows: 1. The average body weights of Cheju Native Cattle at 12 months (101.8 kg) and at 18 months (179.3 Kg) were lightest among the purebreds, and average body weights of Brahman at 12 months and 18 months of age were 196.9 kg and 253.3 kg, respectively, which were heavier than those of the Santa Gertrudis (188.8 kg and 234.7 kg, at the same age). 2. The average body weights of BK (Brahman .times. Cheju Native Cattle) and SK (Santa Gertrudis .times. Cheju Native Cattle) were lighter than any other crossbreds observed. The back crossbred, B2K (BK .times. Brahman) and S2K (SK .times. Santa G.), grew faster and were heavier at 12 months (B2K; 193.4 kg, SK; 183.4 kg) than the crossbred .times. back crossbreds (BK .times. B2K and SK .times. S2K), which were 182.4 kg and 182.5 kg, respectively. The average body weight of BK .times. B2K at 18 months was 241.7 kg, which was considerably higher than those of B2K (238.8 kg) and SK .times. S2K (229.2 kg), which were similar to those of S2K (230.2 kg) (P < 0.01). 3. Sex and year of birth had a highly significant effect (P < 0.01) on the weight of calves, but effects of the age of dam and parity were not noted.