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Alternative Animal Models With Maternal Effects And Foster Dams, L. Dale Van Vleck
Alternative Animal Models With Maternal Effects And Foster Dams, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Effects of foster dams can be included in genetic evaluations using animal models with maternal effects in several ways. The alternatives discussed involve minor changes in computing strategies from strategies used with reduced animal models that predict breeding values for direct and maternal effects. The easiest alternative is to assign foster dams to groups by breed and time period and add equations for fixed effects of breed-period. Random and, assumed, independent effects of foster dams can be nested in breed-period groups. If foster dams do not repeat. then those effects can be absorbed into equations for other fixed effects, additive …
Absorption Of Equations For Non-Parents For An Animal Model With Maternal Effects And Genetic Groups, L. Dale Van Vleck
Absorption Of Equations For Non-Parents For An Animal Model With Maternal Effects And Genetic Groups, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Rules for forming the mixed-model equations for the reduced animal model with all relationships and including maternal effects have been set out by Quaas and Pollak. They also have shown how to simplify the mixed-model equations when genetic group effects are included in the model with what has become known as the Q-P transformation. Westell has given rules for calculating the coefficients for the Q-P transformed equations that are associated with the inverse of the numerator relationship matrix and genetic group effects. Those rules can be extended to include maternal effects and genetic groups for maternal as well as direct …