Effects of Diet Protein Level on Growing-Finishing Pig Performance in a Tropical Environment

Abstract

The effect of increasing the dietary crude protein (CP) level on the growth performance and carcass characteristics of Large White pigs reared in Guadeloupe under tropical climatic conditions was determined. Test animals included 32 females and 32 barrows, each weighing about 24 kg initially. They were individually fed one of four test diets based on corn and soybean-oil meal containing 12, 16, 20, and 24% CP, respectively. The 12 and 16% CP diets were supplemented with synthetic L-lysine hydrochloride. The animals were slaughtered at 95 kg liveweight. On the basis of maximum daily gain and minimum feed conversion ratio, the best level of CP among the various levels compared was 16% for the growing pigs (from 24 to 60 kg liveweight) and 12% for the finishing pigs (from 60 kg to 95 kg liveweight). There was no significant effect of sex on growth performance, but the feed conversion ratio of the finishing females was 8% better than that of the barrows. As the dietary CP level increased, dressing percentage and backfat thickness decreased linearly (P < 0.05). Females were significantly leaner (P < 0.05) than barrows. Further work is needed to determine the optimum level of CP for finishing pigs.