Characterization of Biological Types of Cattle-Cycle III: I. Birth and Weaning Traits2,6

Publisher Website
Google Scholar
Abstract
Gestation length, calving difficulty, perinatal mortality, calf crop weaned, birth weight, preweaning average daily gain (ADG), relative growth rate (RGR) and 200-day weight were examined on 1,610 calves born and 1,536 calves weaned in 1975 and 1976 from 4- to 11-year-old Hereford and Angus dams and by Hereford, Angus, Brahman, Sahiwal, Pinzgauer and Tarentaise sires. Angus dams were superior (P<.01) to Hereford dams in preweaning ADG, RGR and 200-day weight. Hereford dams produced calves with significantly heavier birth weights and longer gestation length than Angus dams. Effects of breeding group and sex of calf were significant for all traits except perinatal mortality and percentage calf crop weaned. All breed of sire groups except Pinzgauer and Tarentaise differed significantly from each other in gestation length; Sahiwal crosses had the longest (294.2 days) and Hereford-Angus crosses had the shortest (284.2 days) gestation length. Brahman crosses exhibited a significantly higher level of calving difficulty than all other breed of sire groups which did not differ (P>.05) from each other. Differences in perinatal mortality were not significant among sire breed groups. Hereford-Angus reciprocal crosses had a significantly higher percentage calf crop weaned than Brahman and Sahiwal crosses. Differences in percentage calf crop weaned were not significant among all other breed of sire groups. Birth weight was heaviest in Brahman crosses (40.6 kg) and lightest in Hereford-Angus (35.4 kg) crosses. All sire breed groups except Sahiwal and Tarentaise crosses differend significantly from each other in birth weight. Brahman crosses had significandy heavier 200-day weight than all other sire breed groups and had significantly higher preweaning ADG than all other breed of sire groups except Tarentaise. Sahiwal and Hereford-Angus crosses were similar (P>.05) in 200-day weight as were Pinzgauer and Tarentaise crosses. All other sire breed groups except Sahiwal and Pinzgauer differed significantly from each other in 200-day weight. Sahiwal and Pinzgauer crosses did not differ significantly from each other or from Hereford-Angus reciprocal crosses in preweaning ADG. Copyright © 1979. American Society of Animal Science . Copyright 1979 by American Society of Animal Science.