Abstract
Perinatal calf losses result in an important reduction in the net calf crop (Wiltbank et al., 1961). Woodward and dark (1959) reported 3.6% of all calves born at the U. S. Range Livestock Experiment Station were dead at birth and that more male than female calves were lost. Results reported by Anderson and Bellows (1967) revealed 79% of the calves lost at birth at the Miles City Station were anatomically normal and injuries resulting from difficult or delayed parturition were the most common cause of death, regardless of age of dam. These workers stated that many calf losses could be prevented if assistance was provided during difficult parturition. Koger et al. (1967) found calves of intermediate birth weight had a higher survival rate than calves of either low or high birth weights. Sagebiel et al. (1969) reported an extensive study of dystocia in reciprocal crossbred cattle. However, there is little information available regarding factors associated with calving difficulty. Copyright © 1971. American Society of Animal Science . Copyright 1971 by American Society of Animal Science.