The effect of barley supplementation on the liveweight gains of autumn-born calves reared on whole or skimmed milk diets

Abstract

Forty, Friesian x Jersey bull calves were fed diets comprising factorial combinations of milk, either whole (4.0 per cent fat) or skimmed (0.1 per cent fat) milk, fed at the rate of 4.5 kg day-1 until the calves were ten weeks old, with crushed barley at four levels from two to 18 weeks of age. The four levels of barley were 0, 25, 50 and 75 per cent of the dry matter intake of the calves. The calves had access to hay ad libitum throughout the experiment. The restricted quantities of skimmed milk fed to the calves did not support rapid gains in liveweight, even when supplemented with high levels of barley. The addition of barley to the diet of the calves reared on whole milk produced no response in terms of growth rate (0.54 kg day-1). However, the calves reared on skimmed milk had greater growth rates when their diet contained 25 per cent barley than with no barley, 0.36 kg day-1 and 0.28 kg day-1 respectively. Further additions of barley did not produce additional responses in growth rate.