|Van Vleck, Lloyd|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 7/24/1995
Publication Date: N/A
Technical Abstract: Direct (D) and maternal (M) breed effects on birth and 200-d weights (kg) were estimated for the nine parental breeds (Hereford [H], Angus [A], Braunvieh [B], Limousin [L], Charolais [C], Simmental [S], Gelbvieh [G], Red Poll [R], and Pinzgauer [P] that contributed to three composite popu- lations (MARC I = 1/4B, 1/4C, 1/4L, 1/8H, 1/8A; MARC II = 1/4G, 1/4S, 1/4H, ,1/4A; and MARC III = 1/4R, 1/4P, 1/4H, 1/4A). Records from each of the three populations, the composite plus the pure breeds and crosses used to create each composite, were analyzed separately. The animal model included fixed effects of contemporary group (birth year-sex-cow age), proportions of individual and maternal heterosis and breed inheritance as covariates; and random effects of additive direct genetic (a), additive maternal genetic (m), covariance (a,m), permanent environment, and residual. Data from a diallel experiment and from grading up to some purebreds were required to separate breed effects into those due to direct and maternal genetic effects. Thus, the results indicate that it may not be possible to estimate direct and maternal breed effects needed to predict EPD's for multi-breed populations from field data.