Effect of enzyme supplementation in diets of growing-finishing pigs on production performances and carcass quality

Two experiments were conducted to evaluate the effects of supplementing corn-pollard based diets with a fiber degrading enzyme (xylanase) on the production performance of growing pigs. The supplemental enzyme's effect on the carcass quality of growing-finishing pigs was also examined in the first of the two experiments. In the first experiment 180 growing pigs averaging 37.26 kg in weight, were assigned to 18 pens with 10 pigs per pen. Using a randomized complete block design (RCBD) the pigs were also assigned to three dietary treatments. Each treatment was replicated six times. The treatments were: 1.) positive control diet (3100Kcal/ME, corn-soya grower ration); 2.) negative control diet (3000 Kcal/ME), corn-soya-pollard grower ration); 3.) negative control diet + enzyme supplement. All diets were in meal form and were fed ad libitum. The second experiment was conducted on a different farm unit. Experiment 2 involved 90 growing pigs which were given the same dietary treatments as those in experiment 1. Xylanase supplementation significantly improved total weight gain by 6.7 percent and average daily gain by 6.8 percent compared to the negative control in experiment 1. Similar improvements were also noted in experiment 2 although these were not found to be significant. The daily gain and total weight gain of the positive control and the xylanase supplemented ration were found to be similar in both experiments. Results in experiment 2 indicated significant improvements (P0.10) in the feed efficiency, protein efficiency, and energy efficiency of the xylanase supplemented diet compared to the negative control. In experiment 1, the feed efficiency, protein efficiency and energy efficiency were similar for all dietary treatments, although treatment 3 (negative control diet + enzyme supplement) resulted in a small but not significant improvement. Enzyme supplementation did not affect the muscle depth and the backfat measurements at P2. However, the addition of xylanase significantly improved the backfat of the pigs at P1 and percent lean against the negative and positive control groups