The effect of plane of nutrition on the performance and carcass characteristics of pigs slaughtered at 100 kg live weight

Abstract

SUMMARY Four equally spaced feeding levels, estimated to cover the range of commercial practice, were examined using a total of 208 pigs over the live-weight range 28–100 kg. The pigs were penned in groups of six or eight and were balanced for sex within pens. Three centres participated in the experiment contributing five, two and one replicates respectively. Efficiency of feed conversion was not significantly affected over the range of feed intakes studied, thus daily gain was linearly related to feed intake. A 10 decrease in feed intake increased killing-out percentage by 0·3 unit and decreased backfat thickness by 1 mm at both the shoulder and mid rump. The corresponding changes in the percentages of subcutaneous fat plus skin and meat were similar in magnitude at approximately 0·85 unit. Muscle quality was reduced with higher feed intakes but weight of liver, as increased. Details of other offal weights and carcass measurements are given.