Using Pelvic Areas and Linear Body Measurements in the Selection for Reduced Dystocia Rates in Sussex Heifers

Abstract

Background: Dystocia in cattle is a global problem which causes many health issues and economical losses in the beef cattle industry. However, to the greatest of our knowledge, use of pelvic areas and linear body measurements in South African Sussex heifers has not yet been reported on literature. Hence, the aim of this study was to use pelvic areas and linear body measurements in the selection of replacement Sussex heifers to reduce dystocia amongst heifers, while improving ease of calving.Methods: One hundred eighty-six first calf Sussex heifers 24 months old, weighing approximately 437 kg were used for this study. A number of six, two-year-old bulls, weighing approximately 800 kg were used for mating the 135 heifers during the first trial with a bull to cow ratio of (1:35; 1:35, 1;35 and 1:30). The second trial consisted of 51 heifers with a number two, two-year-old bulls respectively, with a bull to cow ratio of (1:30 and 1:21).Result: A significant correlation between calving eases score and calf gender, r = -0.35 was revealed. The chances of a heifer to experience dystocia were more when a male calf was born. Birth weight, revealed that higher the birth weight higher the probability of a heifer to experience dystocia. It can be concluded that pelvic measurements in Sussex heifers may be a valuable tool to reduce dystocia.