Calf production of Droughtmaster cows grazing a Townsville stylo-spear grass pasture

Abstract

An experiment was conducted to measure the calf production over four annual calvings of 96 Droughtmaster cows grazing a Townsville stylo-spear grass pasture. There were two replicates of twelve treatments, which were factorial combinations of superphosphate (three levels), stocking rate (two levels) and conservation of hay (two levels). The three rates of application of superphosphate were nil = F0, 126 kg/ha/yr = F1, and 377 kg/ha/yr = F3. Superphosphate had no significant effect on calf birth weights but significantly increased the weaning weight of the calves in three of the four years. The mean annual weaning weights at l80 days of age were F3 = 202.5, F1 = 197.9 and F0. = 180.2 kg. Superphosphate was only the treatment which significantly (P<0.01) increased the mean annual weaning percentage (F3 = 82, F1 = 73, and F0 = 64 per cent), and the mean annual calf liveweight weaned per cow mated (F3 = 165, F1, = 144, and F0 = 116 kg). The stocking rate treatment had a significant effect on calf birthweights and weaning weights in two out of four years. Averaged over four years the respective weights were 30.0 kg and 199.3 kg for the low stocking rate and 28.6 and 187.5 kg for the high stocking rate. The fodder conservation treatment had its greatest effect on calf birthweights and weaning weights during the 1965-66 drought. The respective liveweights were 29.3 kg and 194.1 kg for conserved paddocks and 26.2 and 184.9 kg for unconserved paddocks.