Productivity of Boran cattle and their Friesian crosses at Abernossa Ranch, rift valley of Ethiopia. II. Growth performance
Tóm tắt
Birth (4,197) and weaning (2,441) weight data on Boran, F1 Boran Friesian and three quarter Friesian calves as well as adjusted one-year (390), 2-year (177) and 3-year (364) weights on Boran cattle were analysed to estimate the influence of genetic and environmental factors. Boran, F1 and three quarter calves weighed 25·2, 25·4 and 25·7 kg at birth and 157·5, 176·7 and 179·9 kg at weaning, respectively. All factors included in the analysis and their interaction had significant effects on both traits with the exception of the effect of season of birth and its interaction with breed group on birth weight. Weight of Boran cattle at one-, 2- and 3-years of age were 179, 269 and 338 kg, respectively. Heritability values calculated on the basis of paternal half-sibs were 0·32, 0·24, 0·48, 0·29 and 0·24 for birth, weaning, one-year, 2-year and 3-year weights, respectively. The study indicated that F1 crosses were 12.2% heavier at weaning than Boran calves. Of the environmental factors considered, year of birth was found to be the major source of variation mainly due to variation in the amount of rainfall between years.
Tài liệu tham khảo
Arnason, T. &Kassa-Mersha, H. (1987). Genetic parameters of growth of Ethiopian Boran cattle.Animal Production,44, 201–208.
Barlow, R. &O'Neill, G. H. (1980). Performance of Hereford and crossbred Hereford cattle in the subtropics of New South Wales: Genetic analyses of preweaning performance of first-cross calves.Australian Journal of Agricultural Research,31, 417–427.
Haile-Mariam, M., Banjaw, K., Gebre-Meskel, T. &Ketema, H. (1992). Productivity of Boran cattle and their Friesian crosses at Abernossa Ranch, Rift-Valley of Ethiopia. I. Reproductive performance and preweaning mortality.Tropical Animal Health and Production, In Press.
Harvey, W. R, (1977).User's guide for least-squares and maximum likelihood computer program, Ohio State University, Columbus, USA.
ILCA, International Livestock Centre for Africa (1978). Evaluation of the productivity of Maure and Peul cattle breed at the Sahelian Station, Niono, Mali. ILCA Monograph I, Addis Ababa, Ethiopia.
Kassa-Mersha, H. &Arnason, T. (1986). Non-genetic factors affecting growth of Ethiopian Boran cattle.World Review Animal Production,22, 45–55.
Kebede, B. &Gallal, E. S. E. (1982). A study of body weight from birth to 1 year of age in European-zebu crossbred cattle in Ethiopia.Animal Production,34, 85–93.
Madureira, J. S., Silva, H. M., Fontes, L. R. &Sampaio, I. B. M. (1980). Some factors affecting body weight on Chiana x Nellore crossbreds on pasture. 3. Body weight at 365 days of age.Animal Breeding Abstract,48, 183.
Plasse, D. (1982). Performance recording of beef cattle in Latin America.World Animal Review,41, 11–19.
Rönningen, K., Lampkin, K. &Gravir, K. (1972). Zebu cattle in East-Africa. 2. Estimates of heritability and phenotypic correlation for some traits in Boran cattle.Swedish Journal of Agricultural Research,2. 218–228.
Swensson, C., Schaar, J., Brännäng, E. &Meskel, L. B. (1981). Breeding activities of the Ethio-Swedish integrated rural development project. 3. Reproductive performance of zebu and crossbred cattle.World Animal Review,38, 31–36.
Trail, J. C. M. &Gregory, K. E. (1981). Sahiwal cattle: an evaluation of their potential contribution to Ethiopia.
Trail, J. C. M., Sacker, G. D. &Fisher, I. L. (1971). Crossbreeding beef cattle in western Uganda. 1. Performance of Ankole, Boran and zebu cows.Animal Production,13, 127–141.
Trail, J. C. M., Murray, M., Sones, K., Jibbo, J. M. C., Durkin, J. &Light, D. (1985). Boran cattle maintained by chemoprophylaxis under trypanosomiasis risk.Journal of Agricultural Sciences, (Cambridge),105, 147–166.