ASAS Nonruminant Nutrition: Enzymes, Feed Additives, and Environment Management in Finishing Pigs

The objective of this study was to determine the effect of dietary xylanase supplementation (Porzyme #, Finnfeeds International Ltd., UK) on nutrient digestibility in diets based on either waxy or normal corn and containing 20% wheat middlings, in finishing pigs. The study was conducted using a 4 x 4 Latin Square design having 2 x 2 factorial arrangement of treatments. The treatments were 1) type of corn (waxy vs normal) and 2) enzyme level (0.000 vs 0.125 %). Eight pigs fitted with a post-valve T-cecal cannula were used to measure the apparent ileal digestibility of nutrients. The average initial BW was 101.0 ± 7.25 kg and the average final BW was 118.8 ± 6.22 kg at the end of a four-week study period. The normal corn and waxy corn diets were formulated to the same content(3,241 vs 3,246 ME Kcal/kg; 18.3 vs 18.2 % CP and 0.66 vs. 0.66 % true ileal digestible lysine, respectively). Chromic oxide (0.5 % of the diet) was used as a marker for the determination of the ileal digestibilities. For the first period (week) of the study, pigs were fed 2.4 kg of feed per day in two equal meals at 8 am and 3 pm (1.2 kg per meal). Feed intake was increased by 200 g per day (100 g per meal) after each experimental period. Pigs had free access to water. In each period, the pigs were allowed to adapt to the diets for five days (days 1 to 5). Ileal digesta were collected on days 6 and 7, in two 12-hr periods from 0700 h to 1900 h. There were no interactions (P > 0.05) between corn type and enzyme level for nutrient digestibility. The waxy corn had higher (P < 0.05) ileal digestibility for dry matter and energy than the normal corn (65.5 vs 61.7 SE 0.99 % and 66.4 vs 62.6 SE 1.10 %, respectively). However, there was no difference (P < 0.05) in crude protein digestibility between the corn types. Dietary supplementation with the enzyme at 0.125 % of the diet when compared to the control treatment resulted in higher digestibility for dry matter (60.5 vs 66.7 SE 0.99 %, P < 0.01), protein (70.6 vs 74.0 SE 0.93 %, P < 0.05) and energy (61.5 vs 67.5 SE 1.10 %, P < 0.01). Xylanase supplementation improved ileal digestibility of nutrients in diets based on both normal and waxy corn and wheat middlings.