Hostname: page-component-8448b6f56d-jr42d Total loading time: 0 Render date: 2024-04-20T14:19:27.940Z Has data issue: false hasContentIssue false
  • English
  • Français

A retrospective analysis of culling in a large AI stud

Published online by Cambridge University Press:  02 September 2010

C. J. M. Hinks
C. J. M. Hinks
Affiliation:
ARC Animal Breeding Research Organisation, Edinburgh EH9 3JQ
Get access

Summary

Of 335 British Friesian bulls at AI centres progeny tested during the period 1960–65, 19% were retained for further use in the programme following selection.

A time trend towards more intense selection was observed, from an initial selection rate of 1 in 3 to a final rate of 1 in 7. This appeared to involve increased culling for both daughter type and daughter production.

At all stages of the programme approximately 50% of the selection practised was directed towards attributes other than milk yield.

A comparison of the mean contemporary comparison (c.c.) values of the selected bulls with the values obtained following selection solely for milk yield indicated that the inclusion of daughter type as a criterion of selection reduced the c.c. value of the stud by approximately 33%.

A drastic reduction in the c.c. value of the selected bulls was observed to coincide with the appearance of subsequent groups of daughters in the sire proofs.

Type
Research Article
Information
Animal Production , Volume 20 , Issue 3 , June 1975 , pp. 337 - 343
Copyright
Copyright © British Society of Animal Science 1975

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

REFERENCES

Averdunk, G., Gottschalk, A., Müller, K., Schumann, H. and Schwarz, E. 1973. Rinderzuchtprogramme-aktuell. Tierzüchter 25: 90–95.Google Scholar
Brascamp, E. W. 1973. Model calculations concerning economic optimization of AI-Breeding with cattle. II. Effect of costs on the optimum breeding plan. Z. Tierzücht. Zücht Biol. 90: 126–140.CrossRefGoogle Scholar
Cunningham, E. P. 1972. Optimal estimation of breeding values. Proc. EAAP Genetics Commission, Verona.Google Scholar
Freeman, M. G., Burnside, E. B. and Batra, T. R. 1974. Selection intensities practised in Ontario AI studs. Annual Report, Guelph, 1973–4, pp. 37–39.Google Scholar
Hinks, C. J. M. 1970. The selection of dairy bulls for artificial insemination. Anim. Prod. 12: 569–576.Google Scholar
Hinks, C. J. M. 1971. The genetic and financial consequences of selection amongst dairy bulls in artificial insemination. Anim. Prod. 13: 209–218.Google Scholar
Hinks, C. J. M. 1972. The effects of continuous sire selection on the structure and age composition of dairy cattle populations. Anim. Prod. 15: 103–110.Google Scholar
Hinks, C. J. M. 1974. The planning and organisation of progeny testing with particular reference to numerically small populations and breeds of dairy cattle. Z. Tierzücht. ZüchtBiol. 91: 169–175.Google Scholar
Hunt, M. S., Burnside, E. B., Freeman, M. G. and Wilton, J. W. 1972. Impact of selection, testing and operational procedures on genetic progress in a progeny testing artificial insemination stud. J. Dairy Sci. 55: 829–839.CrossRefGoogle Scholar
Israeli Cattle Breeders Association. 1971. Israeli-Friesian Herd Book Statistics, 1969–71. 22 pp.Google Scholar
Lindhé, B. 1968. Model simulation of A.I. breeding within a dual purpose breed of cattle. Acta. Agric. scand. 18: 33–41.Google Scholar
Milk Marketing Board. 1968-1972. Progeny recorded A.I. stud. Milk Marketing Board, Thames Ditton.Google Scholar
Roman, J., Wilcox, C. J., Becker, R. B. and Koger, M. 1969. Tenure and reasons for disposal of artificial insemination dairy sires. J. Dairy Sci. 52: 1063–1069.CrossRefGoogle Scholar
Skjervold, H. 1967. Selection schemes in relation to artificial insemination. Proc. 9th int. Congr. Anim. Prod., Edinb. 1966. pp. 250–261.Google Scholar
Syrstad, O. 1966. Studies on dairy herd records. III. Estimation of genetic change. Acta. Agric. scand. 16: 3–14.CrossRefGoogle Scholar