Genetic Relationship Between Production and Breeding Efficiency

Abstract

Breeding and production records of 10,-907 Holstein and 10,537 Guernsey lactations from Adohr Milk Farms, Camarillo, California, were analyzed, to determine the phenotypic and genetic parameters o milk and fat production and five measures of breeding efficiency. The five measures of breeding efficiency were: days open, calving interval, days from parturition to first breeding, days from first breeding to conception, and services per conception.