EFFECT OF CAFFEINE ON GROWTH, FEED EFFICIENCY AND LEANNESS OF GROWING PIGS AND ITS INTERACTION WITH CALCIUM, ZINC AND CORN OIL

Abstract

A series of four experiments was conducted to determine the effectiveness of caffeine in promoting increased leanness and feed efficiency in self-fed pigs. A level of 1.5 g of caffeine per kg of feed was one of the most effective levels tested in increasing carcass leanness, but some pigs developed a skin rash which restricted growth rate and reduced feed efficiency. This was accentuated by high levels of dietary zinc or calcium and, in one of two experiments, by a level of 3% corn oil. When a level of 1.0 g/kg of caffeine was used, there was no skin rash, little or no reduction in growth rate, and a slight but nonsignificant increase in feed efficiency. Depth of backfat was significantly reduced (P < 0.01) and the carcass protein: fat ratio was 14–16% higher than in controls. No advantage was found in gradually increasing the caffeine content of the ration from 0.5 g/kg at weaning to 1.5 g/kg eight weeks later, compared with feeding 1.0 g/kg throughout the entire growing, finishing period.