Social Dominance and Temperament of Holstein Cows

Abstract

Social dominance and milking temperament were studied in 27 Wisconsin Holstein herds. Data for height, weight, age, milk production, stage of lactation, milking temperament score, and dominance value were obtained from ],017 cows. Mill~ing temperament score was determined by herdsmen, and dominance value was calculated by a least-squares procedure. Simple correlations of milking temperament score and dominance value with stage of lactation, daily milk yield, and lactation milk yield were close to zero. Correlation between dominance value and milking temperament score was --.05. A multiple regression analysis was conducted with four independent variables: height, weight, age and age-squared. The effects of height on milking temperament score, and age and agesquared on dominance value were statistically significant (P < .05). From sires with five or more daughters in a herd, heritability estimates from paternal halfsib correlations were .07 for adjusted dominance value and .53 for adjusted milking temperament score. Estimates of heritability for height at withers, weight, and lactation milk yield were .67, .68, and .33. Selection for milking temperament score would be more effective than selection for dominance value.