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Corrective mating for linear type traits in dairy cattle
Abstract
The degree of negative assortative mating for 18 linear type traits was investigated in a corrective mating program. To evaluate the degree of assortative mating used, Pearson-Newman correlations between (PTAs) of sires recommended to correct the worst fault trait of the cow and actual scores of cows for worst fault traits were estimated for 18 linear traits. Correlations were obtained by using PTAs from the three recommended sires, or an average obtained from the same three PTAs. When the three PTAs were used, the largest correlations were for rear legs side view ($-$.69), rump side view ($-$.60), and basic form ($-$44). Correlations for the rest of the traits were essentially zero. Correlations were practically zero for all traits when an average of PTAs of the three recommended sires was used. The lack of association between PTAs of recommended sires and scores of cows was due to a large variation among PTAs of recommended sires or a low selection intensity for linear traits of recommended sires. A more careful assigning of sires for recommendations was needed. No evidence of negative assortative mating was found for most of the linear traits in the corrective mating program using scores of cows and PTAs of recommended sires.
Subject Area
Livestock
Recommended Citation
Martinez-Huerta, Octavio, "Corrective mating for linear type traits in dairy cattle" (1993). ETD collection for University of Nebraska-Lincoln. AAI9314418.
https://digitalcommons.unl.edu/dissertations/AAI9314418