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Phenotypic and genetic parameters for lamb weights in a synthetic line of sheep†

Published online by Cambridge University Press:  02 September 2010

T. G. Martin ,
D. I. Sales ,
C. Smith  and
D. Nicholson
D. I. Sales
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
C. Smith
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
D. Nicholson
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
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Abstract

Data on 2120 lambs produced over 7 years in the Animal Breeding Research Organization synthetic Dam Line (49% Finn, 22% East Friesian, 16 % Border Leicester and 13 % Dorset Horn) were analysed by least squares. The effects of sex, age of dam, year of birth, birthrearing class, and age of lamb on weights at birth and at 4, 8, 12 and 16 weeks of age were all appreciable. However, pooled within-year correction factors should be adequate in adjusting records for selection. Heritability estimates for weights at the five ages ranged from 0·17 to 0·24 by the sire component method and from 0·18 to 0·28 by regression of offspring on dam. Previous reports of differences in heritability in singles and in twins were not confirmed. Estimates of the genetic correlations among the various lamb weights were high (0·62 to 1·04) indicating that selection for weight at one age should result in increased weights at all ages.

Type
Research Article
Information
Animal Production , Volume 30 , Issue 2 , April 1980 , pp. 261 - 269
Copyright
Copyright © British Society of Animal Science 1980

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References

REFERENCES

Bohren, B. B., McKean, H. E. and Yamada, Y. 1961. Relative efficiencies of heritability estimates based on regression of off spring on parent. Biometrics 17: 481–491.CrossRefGoogle Scholar
Bowman, J. C. and Broadbent, J. S. 1966. Genetic parameters of growth between birth and sixteen weeks in Down cross sheep. Anim. Prod. 8: 129–135.Google Scholar
Eikje, E. D. 1974. Studies on sheep production records. IV. Genetic, phenotypic and environmental parameters for weight of lambs. Acta Agric. scand. 24: 291–298.CrossRefGoogle Scholar
Gjedrem, T. 1967. Phenotypic and genetic parameters for weights of lambs at five ages. Acta Agric. scand. 17: 199–216.CrossRefGoogle Scholar
Harrington, R. B. and Whiteman, J. V. 1967. Estimates of the repeatability of lamb growth as a characteristic of the ewe. J. Anim. Sci. 26: 239–243.CrossRefGoogle Scholar
Harvey, W. R. 1960. Least-squares analysis of data with unequal subclass numbers. U.S. Dep. Agric, ARS-20–8.Google Scholar
Olson, L. W., Dickerson, G. E. and Glimp, H. A. 1976. Selection criteria for intensive market lamb production: growth traits. J. Anim. Sci. 43: 78–89.CrossRefGoogle Scholar
Osman, A. H. and Bradford, G. E. 1965. Effects of environment on phenotypic and genetic variation in sheep. J. Anim. Sci. 24: 766–774.CrossRefGoogle ScholarPubMed
Owen, J. B., Brook, L. E., Read, J. L., Steane, D. E. and Hill, W. G. 1978. An evaluation of performance-testing of rams using artificial rearing. Anim. Prod. 27: 247–259.Google Scholar
Shelton, M. and Campbell, F. 1962. Influence of environmental adjustments on heritability of weaning weight of range Rambouillet lambs. J. Anim. Sci. 21: 91–94.CrossRefGoogle Scholar
Thrift, F. A., Whiteman, J. V. and Kratzer, D. D. 1973. Genetic analysis of preweaning and postweaning lamb growth traits. J. Anim. Sci. 36: 640–643.CrossRefGoogle Scholar
Vogt, D. W., Carter, R. C. and McClure, W. H. 1967. Genetic and phenotypic parameter estimates involving economically important traits in sheep. J. Anim. Sci. 26: 1232–1238.CrossRefGoogle ScholarPubMed