Growth and carcass characteristics of crossbred and straightbred Hereford steers. I. Post-weaning growth

Abstract

Post-weaning growth characteristics were examined in 28 Hereford, 27 Brahman x Hereford, 23 Simmental x Hereford and 26 Friesian x Hereford steers which were grazed on pasture in a central coastal environment at Paterson, N.S.W. Sixty-seven steers from a 1973 calving were allocated to three groups to be slaughtered when the mean liveweights of the Herefords were approximately 270, 370 and 470 kg. Thirty-seven steers from a 1974 calving were allocated to two groups to be slaughtered when the average liveweights of the Herefords were 470 and 570 kg. Average daily liveweight gains of the crossbred steers were greater (average 19%) than the Hereford steers from weaning to the four slaughter weights (P < 0.05). Of the crossbreds, the Brahman cross steers grew faster than the Simmental cross steers (P < O.05), although the difference was not significant at the highest slaughter weight. The growth advantage of the crossbreds was mainly realized in the periods of slow growth (mean growth rate of 320 g/day) during the late summer, autumn and winter months. During these periods the Brahman cross steers grew faster than the Herefords by an average of 89% (P < 0.05) and the Simmental and Friesian cross steers grew 39% faster than the Herefords (P < 0.05). In the periods of fast growth (mean growth rate of 667 g/day), during the spring and early summer months, there was no significant difference between the sire breeds in growth rate (P > 0.05).