Data from 1456 purebred and crossbred cows offive different crossbred groups involving the Holstein (H) and Gyr (G) breeds(H; ¾H ¼G; ½H ½G; 3/8H 5/8Ge ¼H ¾G) were used to compare their milk production and reproductivetraits in the Brazilian central plateau region. The performance traits studiedwere: average daily milk production (DMP); lactation length (LL); total productionin 305 days (P305) and age at first calving (AFC), gestation length (GL) andcalving interval (CI). Higher averages of DMP and P305 were observed for animals¾H ¼G and ½H ½G and the smallest ones for crossbred animalswith larger proportion of the Gyr breed (¼H ¾G). The lowest valuesof AFC and CI were observed for ¾H ¼G animals. These results indicatethe importance of crossbreeding strategies to produce animals that are moreadapted to the environmental conditions of the region. Holstein purebreds probablydo not express their full genetic potential due to nutritional and/or heat stress.
