The supplementation of pig diets with oleandomycin

Abstract

SUMMARYA trial is described in which normal rations containing oleandomycin at 12½ and 25 g. per ton of meal and without the additive were given to females and castrates which had previously received creep feed with and without oxytetracycline.A total of 48 pigs were individually fed on the rations from 50 to 200 lb. live-weight, a restricted scale of intake based on live-weight being adopted.Between 50 and 100 lb. live-weight rate and efficiency of gain were significantly better in pigs which had not received antibiotic in the creep feed. No other treatment had any significant effect on performance.Oleandomycin did not influence carcass measurements or dressing percentage. Minimum depth of fat at the mid-back was significantly greater in pigs which had received oxytetracycline in the creep feed while castrates had a significantly greater depth of fat at the shoulder and mid-back compared with females.Pigs receiving the lower level of oleandomycin had significantly lighter kidneys than the control animals. Other visceral weights were not significantly influenced by the antibiotic, but females had significantly heavier kidneys, spleen and liver weights than castrates.