Precalving Body Size and Pelvic Area Relationships in Hereford Heifers

The relationships among area of the pelvic opening, hip width, rump length and body weight have been studied prior to calving in 3-year-old, primiparous Hereford heifers. Analyses indicated highly significant correlations among all measurements studied. Standard partial regression coefficients depicting effects of body weight, hip width and rump length on pelvic area were all highly significant. The effect of body weight was the most important followed by hip width and rump length. Findings suggest that larger skeletal size may be indicative of larger pelvic openings.