Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-23T05:03:37.975Z Has data issue: false hasContentIssue false
  • English
  • Français

Genetic and environmental effects on age at first calving and calving interval of naturally bred Boran (zebu) cows in Ethiopia

Published online by Cambridge University Press:  02 September 2010

M. Haile-Mariam  and
H. Kassa-Mersha
M. Haile-Mariam
Affiliation:
Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, S-750 07 Uppsala, Sweden
H. Kassa-Mersha
Affiliation:
Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, S-750 07 Uppsala, Sweden
Get access

Abstract

Twenty-four years of data from a Boran cattle breeding and improvement ranch in the Rift Valley of Ethiopia were used to study the influence of genetic and environmental factors on age at first calving (AFC) and calving interval (CD using an individual animal model.

The mean AFC and Cl were 41-8 months and 442 days, respectively. The h2 values for AFC were 0·062 and 0·075 when estimated on the original and selected data, from which cows that did not calve after 5 years of age were deleted, respectively. The h2 values for CI were 0·037 and 0·043 when estimated on the original and selected data, from which cows with AFC higher than 5 years and CI longer than 2 years were deleted, respectively. The corresponding c2 values (ratio of permanent environmental variance to total) were 0·031 and 0·028 for the respective data sets. Parameter estimates of the original data from bivariate analysis were 0·012 (h2), 0·065 (h2), -0·054 and -0·176 for first CI, AFC, their genetic and environmental correlation, respectively. The h2 values estimated in a bivariate analysis of the first three CIs varied between 0·002 and 0·093. Year and season had significant effects on both traits. The annual genetic change for both traits was not significant while the solutions for year effects were highly variable. The regression of the solutions of year effects for AFC on year showed that it increased by about 10 days while the variation in CI was due to random year to year fluctuation.

Keywords

Boranenvironmental factorsfertilitygenetic parameters
Type
Research Article
Information
Animal Production , Volume 58 , Issue 3 , June 1994 , pp. 329 - 334
Copyright
Copyright © British Society of Animal Science 1994

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bourdon, R. M. and Brinks, J. S. 1982. Genetic, environmental and phenotypic relationships among gestation length, birth weight, growth traits and age at first calving in beef cattle. Journal of Animal Science 55: 543–553.CrossRefGoogle ScholarPubMed
Duarte-Ortuno, A., Thorpe, W. and Tewolde, A. 1988. Reproductive performance of purebred and crossbred beef cattle in tropics of Mexico. Animal Production 47: 11–20.Google Scholar
Galina, C. S. and Arthur, G. H. 1989. Review of cattle reproduction in the tropics. Parts 1 and 2. Animal Breeding Abstracts 57: 583–590; 679-686.Google Scholar
Groeneveld, E. 1990. PEST user's manual. Department of Animal Science, University of Illinois, Urbana.Google Scholar
Haile-Mariam, M., Banjaw, K., Gebre-Meskel, T. and Ketema, H. 1993. 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 25: 239–248.CrossRefGoogle Scholar
Kassa-Mersha, H. and Arnason, T. 1986. Non-genetic factors affecting growth of Ethiopian Boran cattle. World Review of Animal Production 22:45–55.Google Scholar
Mackinnon, M. J., Taylor, J. F. and Hetzel, D. J. S. 1990. Genetic variation and covariation in beef cow and bull fertility, journal of Animal Science 68: 1208–1214.CrossRefGoogle ScholarPubMed
Maule, J. P. 1990. The cattle of the tropics. University of Edinburgh, Centre for Tropical Veterinary Medicine, Edinburgh.Google Scholar
Meyer, K. 1989. Restricted maximum likelihood to estimate variance components for animal models with several random effects using a derivative-free algorithm. Genetics Selection and Evolution 21: 317–340.CrossRefGoogle Scholar
Meyer, K., Hammond, K., Parnell, P. F., Mackinnon, M. J. and Sivarajasingam, S. 1990. Estimates of heritability and repeatability for reproductive traits in Australian beef cattle. Livestock Production Science 25:15–30.CrossRefGoogle Scholar
Milagres, J. C., Dillard, E. U. and Robison, O. W. 1979. Heritability estimates for some measures of reproduction in Hereford heifers. Journal of Animal Science 49: 668–674.CrossRefGoogle Scholar
Rege, J. E. O., Lomole, M. A. and Wakhungu, J. W. 1992. An evaluation of a long-term breeding programme in a closed Sahiwal herd in Kenya. I. Effect of non-genetic factors on performance and genetic parameters estimates. Journal of Animal Breeding and Genetics 109: 364–373.CrossRefGoogle Scholar
Seebeck, R. M. 1973. Sources of variation in the fertility of a herd of Zebu, British and Zebu × British cattle in Northern Australian. Journal of Agricultural Science, Cambridge 81: 253–262.CrossRefGoogle Scholar
Thorpe, W., Cruickshank, D. K. R. and Thompson, R. 1981. Genetic and environmental influences on beef cattle production in Zambia. 4. Weaner production from purebred and reciprocally crossbred dams. Animal Production 33:165–177.Google Scholar
Trail, J. C. M. and Gregory, K. E. 1981. Characterisation of the Boran and Sahiwal breeds of cattle for economic characters. Journal of Animal Science 52:1286–1293.CrossRefGoogle Scholar
Trail, J. C. M., Gregory, K. E., Durkin, J. and Sandford, J. 1984. Crossbreeding cattle in beef production programmes n i Kenya. II. Comparison of purebred Boran and Boran crossed with the Red Poll and Santa Gertrudis breeds. Tropical Animal Health and Production 16: 191–200.CrossRefGoogle Scholar