PSIV-15 Determining the effects of increasing levels of xylanase in nutrient adequate diets on growth performance, carcass characteristics of growing-finishing pigs

Abstract

A total of 1,944 mixed sex growing-finishing pigs (PIC; 337×1050; initial BW of 22.5±0.53 kg) were used in a 131-d growth trial to determine the effects of increasing levels of xylanase in adequate diets on grow-finish pig growth performance and carcass characteristics. The 6 dietary treatments consisted of corn, soybean meal, and dried distillers grains with solubles with added xylanase (Belfeed B 1100 MP; Jefo Nutrition Inc., Saint-Hyacinthe, Quebec) formulated to: 0, 5, 10, 20, 40, and 75 of enzymatic activity for xylanase (IU/kg) with 27 pigs per pen and 12 replicates per treatment. Data were analyzed as a randomized complete block design using lmer function in lme4 package in R with pen considered as the experimental unit, body weight as blocking factor, and treatment as a fixed effect. From d 0 to 70, there was a tendency (quadratic, R=0.068) for average daily gain (ADG) to decrease and then increase with increasing added xylanase, but there was no evidence (R >0.10) of differences for average daily feed intake (ADFI) and feed efficiency (G/F). From d 70 to 131 and overall, there was no evidence of difference (R >0.10) observed for ADG, ADFI, and F/G. There was no evidence for difference (R >0.10) between treatments for number of pigs receiving injectable treatments or mortalities. For carcass traits, increasing xylanase increased then decreased (quadratic, R=0.010) percentage carcass yield. Also, as xylanase increased, percentage lean decreased (linear, R=0.038) and backfat marginally increased (linear, R=0.066). In conclusion, adding increasing levels of xylanase in nutrient adequate diets did not influence growth performance or mortality but did improve carcass yield when intermediate levels were fed.