Evaluations of Holstein Bulls and Cows in Ecuador
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چکیده
Adjustment factors for age and month of calving were developed from Holstein lactation m r d s in Ecuador. Age factors were similar to those in the United States, but calendar month effects were small, apparently because of uniform feeding and management as the result of a similar climate throughout the year. Genetic evaluations were computed with the USDA animal model system but without identification for dams. Thus, resulting evaluations were essentially from a sire model. Highest bull evaluations were associated with semen imported ftom the United States. Highest cow evaluations were for daughters of United States bulls. Use of United States bulls has tended to increase in recent years. Correlation between animal model evaluations from United States data and those from Ecuadorean data for 107 bulls in common was much less than expected (.42 vs. .72), perhaps because of assortative mating, genotypeenvironment interaction, or a combination of the two. (
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