Effects of xylanase supplementation on digestibility and performance of growing-finishing pigs fed Chinese double-low rapeseed meal inclusion diets: in vitro and in vivo studies
An in vitro and a feeding trial were conducted to investigate theeffect of xylanase supplementation on the feeding value of growing-finishing pig diets containing high proportions of Chinese double-low rapeseed meal (DLRM). Seven diets were formulated to meet NRC (1998) nutrient requirements. Diet 1 based on corn and soybean meal was used as positive control 1, and diet 2, a practical diet incorporated with conventional level of Chinese DLRM (6％ and 10％ of diet for the growing and finishing phase, respectively), as positive control 2. Diet 3 contained higher level of DLRM (10％ and 15％ of diet for the growing and finishing phase, respectively) as the negative control. Diet 3 plus xylanase at 0.10, 0.25, 0.50 and 0.70 g/kg diet created diets 4, 5, 6and 7, respectively. The seven diets for the growing phase with triplicate each were incubated by the in vitro two-stage incubation method and digestibility of DM, CP and NDF was determined. In vitro, the negative control had a lower CP (P＜0.05) and NDF (P =0.06) digestibility than positive control 1. Both DM and CP digestibility were increased (P＜0.05) by xylanase supplementation either at 0.50 or 0.70 g/kg diet, and NDF digestibility was improved following any test levels of xylanase addition. There was a high linear correlation (r2 ＞ 0.90, P＜0.05) between the activity of the enzyme when transformed into its logarithmic value and in vitro digestibility of DM, CP or NDF. In the feeding trial, 112 crossbred pigs were randomly assigned to seven dietary treatments with 16 replicate pens of one pig each. Within the inclusion levels of xylanase an obvious dose effect on growth rate was observed (r2 =0.79, P＜0.05) and xylanase addition at 0.70 g/kg diet resulted in significantly increased ADG over the negative control (878 g/d vs. 828 g/d, P＜0.05) during the growing phase, whereas the similar inclusion effect was not observed during the finishing phase. It would appear that nutritional values of corn and Chinese DLRM diet by pigs could be enhanced and therefore it was feasible to improve dietary inclusion levels of Chinese DLRM by appropriate amount of xylanase addition.
Chinese DLRM Digestibility Performance Pigs Xylanase
FANG Zhengfeng PENG Jian TANG Tiejun LIU Zhenli DAI Jinjun JIN Lizhi
College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070 P.R.China Finnfeeds International Pte Ltd, 61 Science Park Road, Singapore 117525
国际会议
第十二届国际油菜大会( The 12th International Rapeseed Congress)
武汉
英文
1846-1850
2007-03-26（万方平台首次上网日期，不代表论文的发表时间）