Studies on liquid skim milk for growing pigs. The effect of its abrupt removal from the diet and of supplementation with copper sulphate or amino acids

Abstract

Results of four experiments involving a total of 124 pigs covering the growth period between about 40 and 210 lb. live-weight indicated that:1. The growth rate and efficiency of food utilisation of pigs receiving liquid skim milk up to a maximum of 5¼ pints per head per day, was better than that of pigs receiving a balanced all-meal diet. This was equally so whether the liquid skim milk was fed throughout the growing period or was abruptly removed from the diet at either about 75 lb. or 120 lb. live-weight, provided the all-meal diet fed subsequently contained adequate protein.2. The addition of 0·1% copper sulphate to the meal fed with liquid skim milk significantly improved the growth rate and efficiency of food conversion.3. The addition of 0·2% dl-lysine and 0·1% dl-methionine to the meal fed with liquid skim milk had no effect on the performance of the pigs.4. Withdrawal of a protein supplement from the rations of pigs after they reached about 120 lb. live-weight adversely affected their performance.