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Optimal mature size of angus cows for maximum cow productivity†

Published online by Cambridge University Press:  02 September 2010

T. S. Stewart  and
T. G. Martin
T. S. Stewart
Affiliation:
Department of Animal Sciences, Purdue University, West Lafayette, Indiana, USA
T. G. Martin
Affiliation:
Department of Animal Sciences, Purdue University, West Lafayette, Indiana, USA
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Abstract

Lifetime maternal performance records of 113 Angus cows born over a 12-year period were used to estimate the relationship between cow size characters, mature size (A) and maturation rate (K), and lifetime maternal performance characters, years in the herd (YH), number of calves (NC), total calf weight (TW), average calf weight at weaning (AW) and calf weight per year in herd (kg/year). Pertinent reproductive management of the herd was: heifers were mated to calve as 2-year-olds; any heifer failing to calve or any cow failing to wean a calf a second time was culled; all matings were to purebred Angus sires. Mean cow mature size was 487 ± 5 kg with a maturation rate of 0·058 ± 0·001. Means for maternal characters were: YH, 7·4 ± 0·4; NC, 6·4 ± 0·3; TW, 1283 ± 71; AW, 200 + 1·8; and kg/year, 173 ±5·1. The correlations between maternal characters and A and K, respectively, were: YH, −0·21, 0·15; NC, −0·21, 0·15; TW, −0·16, 0·12; AW, 0·20, −0·15; and kg/year, 0·05, −004. The regression of maternal characters on mature size was quadratic in every instance with optimal cow size for each character being: YH, 468; NC, 465; TW, 471; AW, 493; and kg/year, 475. The optimal cow size for average weight of calf weaned was 18 to 25 kg heavier than the optimal size for those characters associated with fertility. Relationships between maturation rate and maternal performance were not statistically significant.

Type
Research Article
Information
Animal Production , Volume 37 , Issue 2 , October 1983 , pp. 179 - 182
Copyright
Copyright © British Society of Animal Science 1983

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References

REFERENCES

Blaxter, K. L. 1964. The efficiency of feed conversion by livestock. Jl R. agric. Soc. 125: 87–99.Google Scholar
Brody, S. 1945. Bioenergetics and Growth. Reinhold, New York.Google Scholar
Brown, J. E. and Brown, C. J. 1972. The influence of mature weight and rate of maturing on individual beef cow efficiency. Bull. Univ. Arkansas, No. 774.Google Scholar
Brown, J. E., Brown, C. J. and Butts, W. T. 1972. A discussion of the genetic aspects of weight, mature weight and rate of maturing in Hereford and Angus cattle. J. Anim. Sci. 34: 525–537.CrossRefGoogle ScholarPubMed
Brown, C. J. and Butts, W. T. 1979. Size and growth of Angus cows in the southern regions. Southern Cooperative Ser. Bull. No. 240, Univ. Arkansas.Google Scholar
Fitzhugh, H. A. Jr. 1976. Analysis of growth curves and strategies for altering their shape. J. Anim. Sci. 42: 1036–1051.CrossRefGoogle ScholarPubMed
Fitzhugh, H. A. 1978. Animal size and efficiency, with special reference to the breeding female. Anim. Prod. 27: 393–401.Google Scholar
Fitzhugh, H. A. Jr, and Taylor, ST C. S. 1971. Genetic analysis of degree of maturity. J. Anim. Sci. 33: 717–725.CrossRefGoogle ScholarPubMed
Hammond, J., Edwards, J. and Walton, A. 1941. Animal breeding in relation to environmental conditions. Jl R. agric. Soc. 102: 156–170.Google Scholar
Long, C. R., Cartwright, T. C. and Fitzhugh, H. A. Jr 1975. Systems analysis of sources of genetic and environmental variation in efficiency of beef production: cow size and herd management. J. Anim. Sci. 40: 409–420.CrossRefGoogle Scholar
Martin, T. G. and Alenda, R. 1983. Genetic trends in a herd of Angus selected for 365-day weight over 21 years. Proc. Wld Congr. Sheep and Beef Cattle Breeding, New Zealand. In pressGoogle Scholar
Morris, C. A. and Wilton, J. W. 1975. Influence of mature cow weight on economic efficiency in beef cattle production. Can. J. Anim. Sci. 55: 233–250.CrossRefGoogle Scholar
Nelsen, T. C. 1979. Heterosis for size and maturing rate in cattle. Ph.D. Thesis, Texas A and M Univ., College Station.Google Scholar
Smith, G. M., Fitzhugh, H. A. Jr, Cundiff, L. V., Cartwright, T. C. and Gregory, K. E. 1976. A genetic analysis of maturing patterns in straightbred and crossbred Hereford, Angus and Shorthorn cattle. J. Anim. Sci. 43: 389–395.CrossRefGoogle Scholar