A Multiple-Trait Herd Cluster Model for International Dairy Sire Evaluation

SUMMARYSeveral of the various dairy sire evaluation methods now in use account for the genetic level of contemporary herdmates. In the cumulative difference method of Bar-Anan and Sacks the contemporary comparison estimate is first calculated and then adjusted by taking into account the genetic level of the contemporaries. These estimates depend on the genetic level of the herdmates. A modification of the procedure in which account is taken of the herdmates' genotype before regressing for small numbers would remedy this deficiency without increasing computing costs.

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Effects of genetic and environmental variance on dairy sire evaluation

10.31274/rtd-180815-715 ◽

1963 ◽

Author(s):

Ben Bereskin

Keyword(s):

Environmental Variance ◽

Sire Evaluation ◽

Dairy Sire

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Biases in Dairy Sire Evaluation Attributable to Genetic Trend and Female Selection

Journal of Dairy Science ◽

10.3168/jds.s0022-0302(71)85968-4 ◽

1971 ◽

Vol 54 (7) ◽

pp. 1041-1051 ◽

Cited By ~ 20

Author(s):

G.L. Hargrove ◽

J.E. Legates

Keyword(s):

Genetic Trend ◽

Sire Evaluation ◽

Dairy Sire

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ESTIMATION OF VARIANCES AND COVARIANCES FOR USE IN A MULTIPLE TRAIT BEEF SIRE EVALUATION MODEL

Canadian Journal of Animal Science ◽

10.4141/cjas81-065 ◽

1981 ◽

Vol 61 (3) ◽

pp. 531-538 ◽

Cited By ~ 7

Author(s):

L. R. SCHAEFFER ◽

J. W. WILTON

Keyword(s):

Maximum Likelihood ◽

Growth Traits ◽

Evaluation Model ◽

Genetic Correlations ◽

New Method ◽

Multiple Trait ◽

Weaning Weight ◽

Calving Ease ◽

Modified Maximum Likelihood ◽

Sire Evaluation

A modified maximum likelihood multiple trait procedure was used to estimate sire and error variances and covariances among calving ease, weaning weight, and yearling weight calf records. A description of the new method is presented. Data included 477 757 calves of 13 breeds of sire. Breeds of sire with over 9 000 calf records had genetic correlations between calving ease and growth traits that ranged from −.02 to −.43, and between weaning weight and yearling weight from.63 to.91. Heritability estimates for calving ease ranged from.07 to.30 for male calves and from.14 to.40 for female calves; for weaning weight from.12 to.31 for male calves and from.15 to.40 for female calves; and for yearling weight from.07 to.21 for male calves and from.17 to.52 for female calves. The residual error correlations between calving ease and the growth traits ranged from −.09 to.13 for male calves and from −.04 to.15 for female calves, and between weaning weight and yearling weight they varied around.7. The new estimates are recommended for use in multiple trait sire evaluation.

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