Advertisement

Journal of Applied Genetics

, Volume 47, Issue 2, pp 125–130 | Cite as

Adjustments for heterogeneous herd-year variances in a random regression model for genetic evaluations of Polish Black-and-White cattle

  • Tomasz Strabel
  • Tomasz Jankowski
  • Janusz Jamrozik
Article

Abstract

The study investigated the existence of heterogeneous variance in first-lactation daily milk yield of Polish Black-and-White cows across herds in different years. Bayesian Information Criterion was used to show that the model with unequal residual variances for different herd-years was more plausible than the model assuming equal variances. A method of adjusting phenotypic records was developed to account for unequal variability in herd-years. Factors used for the data adjustment considered variation of general residuals and residuals for specific herd-years. The size of herd-year was also taken into account. Varied power of corrections was used to analyze the effect of adjustment on estimated breeding values. The method was applied to daily milk records of 817 165 primiparous cows. The effectiveness of the data adjustment was evaluated by the analysis of differences between each bull’s breeding value and its parental index. Data correction reduced the average difference and variance of differences between breeding values and parental indices. Accounting for the size of herd-year classes in correction factors improved the efficiency of heterogeneous variance adjustment.

Key words

breeding value dairy cattle heterogeneous variance 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Boldman KG, Freeman AE, 1990. Adjustment for heterogeneity of variance by herd production level in dairy cow and sire evaluation. J Dairy Sci 73: 503–512.CrossRefGoogle Scholar
  2. De Veer JC, van Vleck LD, 1987. Genetic parameters for first lactation milk yields at three levels of herd production. J Dairy Sci 70: 1434–1441.CrossRefPubMedGoogle Scholar
  3. Dong MC, Mao IL, 1990. Heterogeneity of (co)variance and heritability on different levels of intraherd milk-production variance and of herd average. J Dairy Sci 73: 843–851.CrossRefGoogle Scholar
  4. Gengler N, Wiggans GR, Gillon A, 2004. Estimated heterogeneity of phenotypic variance of test-day yield with a structural variance model. J Dairy Sci 87: 1908–1916.CrossRefPubMedGoogle Scholar
  5. Hill WG, Edwards MR, Ahmed MKA, Thompson R, 1983. Heritability of milk yield and composition at different levels and variability of production. Anim Prod 36: 59–68.CrossRefGoogle Scholar
  6. Interbull 2005.www-interbull.slu.se Google Scholar
  7. Jagusiak W, Żarnecki A, 2002. Characteristics of bull-dam herds. Electronic Journal of Polish Agricultural Universities, Anim Husbandry 5.www.ejpau.media.pl/series/volume5/issue1/animal/art-07.html Google Scholar
  8. Kirkpatrick M, Lofsvold D, Bulmer M, 1990. Analysis of inheritance, selection and evolution of growth trajectories. Genetics 124: 979–993.PubMedGoogle Scholar
  9. Meinert TR, Pearson RE, Vinson WE, Cassell BG, 1988. Effect of within-herd variance and herd mean production on response to selection within herd. J Dairy Sci 71: 3405–3414.CrossRefGoogle Scholar
  10. Meuwissen THE, De Jong G, Engel B, 1996. Joint estimation of breeding values and heterogeneous variances of large data files. J Dairy Sci 79: 310–316.CrossRefGoogle Scholar
  11. Mirande SL, van Vleck LD, 1985. Trends in genetic and phenotypic variances for milk production. J Dairy Sci 68: 2278–2286.CrossRefGoogle Scholar
  12. NRS, 2005. Breeding value evaluation production traits, technical information on the breeding values evaluation of the production traits. www.nrs.nlGoogle Scholar
  13. SAS Institute, 1998. User’s guide: Statistics, Version 7. SAS Institute, Inc., Cary, NC.Google Scholar
  14. Schaeffer LR, Jamrozik J, Kistemaker GJ, van Doormal BJ, 2000. Experience with a test-day model. J Dairy Sci 83: 1135–1144.CrossRefPubMedGoogle Scholar
  15. Short TH, Blake RW, Quaas RL, van Vleck LD, 1990. Heterogeneous within-herd variance. 1. Genetic parameters for first and second lactation milk yields of grade Holstein cows. J Dairy Sci 73: 3312–3320.CrossRefGoogle Scholar
  16. Strabel T, Jamrozik J, 2006. Genetic parameters for milk production traits of Polish Black-and-White cattle estimated with large-scale multiple lactation random regression test-day models. J Dairy Sci (Accepted).Google Scholar
  17. Strabel T, Szyda J, Ptak E, Jamrozik J, 2005. Comparison of random regression test-day models for Polish Black-and-White cattle. J Dairy Sci 88: 3688–3699.CrossRefPubMedGoogle Scholar
  18. Szydłowski M, Szwaczkowski T, 1993. The effect of grouping herds according to production level on the heritability of milk traits in cattle. Anim Sci Pap Rep 11: 295–300.Google Scholar
  19. Tsuruta S, Misztal I, Stranden I, 2001. Use of the preconditioned conjugate gradient algorithm as a generic solver for mixed-model equations in animal breeding applications. J Anim Sci 79: 1166–1172.PubMedGoogle Scholar
  20. Van der Werf JHJ, Meuwissen THE, de Jong G, 1994. Effects of correction for heterogeneity of variance on bias and accuracy of breeding values estimation for Dutch dairy cattle. J Dairy Sci 77: 3174–3184.CrossRefPubMedGoogle Scholar
  21. Visscher PM, Hill WG, 1992. Heterogeneity of variance and dairy cattle breeding. Anim Prod 55: 321–329.CrossRefGoogle Scholar
  22. Wade KM, Quaas RL, 1993. Solutions to a system of equations involving a first-order autoregressive process. J Dairy Sci 76: 3026–3032.CrossRefGoogle Scholar
  23. Weigel KA, Lawlor TJ, 1994. Adjustment for heterogeneous variance in genetic evaluations for conformation of United States Holsteins. J Dairy Sci 77: 1691–1701.CrossRefPubMedGoogle Scholar
  24. Wiggans GR, VanRadenPM, 1991. Method and effect of adjustment for heterogeneous variance. J Dairy Sci 74: 4350–4357.CrossRefPubMedGoogle Scholar

Copyright information

© Institute of Plant Genetics, Polish Academy of Sciences, Poznan 2006

Authors and Affiliations

  • Tomasz Strabel
    • 1
  • Tomasz Jankowski
    • 1
  • Janusz Jamrozik
    • 2
    • 3
  1. 1.Department of Genetics and Animal BreedingAugust Cieszkowski Agricultural UniversityPoznańPoland
  2. 2.Department of Animal and Poultry Science, Centre for Genetic Improvement of LivestockUniversity of GuelphCanada
  3. 3.Department of Animal Genetics and BreedingNational Research Institute of Animal ProductionBalicePoland

Personalised recommendations