Reproductive performance and calf growth to weaning of Hereford and Belmont Red cattle in subtropical, subcoastal Queensland

Abstract

The reproductive performances of herds of Belmont Red (BR) and Hereford (H) breeding females were compared at Narayen Research Station in south-eastern Queensland on cleared and sown brigalow land (Brigalow) and on native speargrass pastures with trees killed (Speargrass). The conception rates (BR, 83%; H, 83%) and calving rates (BR, 80%; H, 78%) were similar, but BR calves grew faster (P<0.001) than H calves especially on Speargrass where BR had a 13% advantage. The mean calving date of H was 13 days earlier than BR (18 days on Speargrass; 7 days on Brigalow). Values for the weight of calfweaned per cow mated for BR and H respectively were 195 kg and 181 kg on Brigalow, and 155 kg and 140 kg on Speargrass. Breed x pasture-type interactions were significant for cow weight, time of calving and calf weight-for-age at weaning. There were significant effects of pasture type on animal performance. Compared with Speargrass, cows on Brigalow were heavier, they calved earlier and their calves grew faster. Production, measured as weight of calf weaned, was 3 times higher on Brigalow than on Speargrass per unit area and 30% higher per cow mated.