Perera W N U, Abdollahi M R, Zaefarian F, Wester T J, Ravindran V
Monogastric Research Centre, School of Agriculture and Environment, Massey University, Palmerston North 4442, New Zealand; Department of Animal Science, Faculty of Agriculture, University of Peradeniya, Peradeniya 20400, Sri Lanka.
Monogastric Research Centre, School of Agriculture and Environment, Massey University, Palmerston North 4442, New Zealand.
Poult Sci. 2021 Aug;100(8):101166. doi: 10.1016/j.psj.2021.101166. Epub 2021 Mar 27.
The influence of supplemental carbohydrase (Carb) and conditioning temperature (CT) on growth performance, nutrient utilization and intestinal morphometry of broilers (d 1-21) fed barley-based diets was examined in a 2 × 3 factorial arrangement, evaluating 2 levels of Carb (0 and 150 g/tonne of feed) and three CT (60, 74, and 88°C). A total of 288, 1-day-old male broilers (8 birds/cage; 6 cages/treatment) were used. The activities of endo-1,4-β- glucanase, endo-1,3 (4)-β-glucanase and endo-1,4-β-xylanase in the Carb were 800 BGU/g, 700 BGU/g and 2,700 XU/g, respectively. On d 21, ileal digesta was collected for the determination of nutrient digestibility. There was no significant interaction between Carb and CT for any tested parameter. Supplemental Carb, regardless of CT, increased weight gain (WG; P < 0.05) and reduced feed per gain (F/G; P < 0.001) by 30 g/bird and 6.5 points, respectively. Increasing CT to 88°C reduced (P < 0.05) WG, but increased (P < 0.05) F/G compared to the diets conditioned at 60° and 74°C. Regardless of CT, Carb enhanced (P < 0.05) the digestibility of starch and AMEn by 1.15% and 32 kcal/kg, respectively. Compared to the diets conditioned at 60° and 74°C, CT at 88°C reduced (P < 0.05) digestibility of dry matter, nitrogen, phosphorus, gross energy, and AMEn. Birds fed diets conditioned at 88°C showed lower (P < 0.05) starch digestibility compared to those fed diets conditioned at 60°C. Conditioning at 88°C increased (P < 0.05) jejunal digesta viscosity by 10.2% compared to diets conditioned at 60° and 74°C. Overall, Carb supplementation improved WG, F/G, starch digestibility and AMEn in broilers fed barley-based diets, irrespective of CT applied. Conditioning barley-based diets at 88°C impaired the ability of birds to utilize nitrogen, starch, phosphorus and energy, and consequently deteriorated WG and F/G. The lack of significant interactions between Carb and CT indicated that negative impacts caused by high CT on bird performance and nutrient utilization occurred regardless of Carb enzyme supplementation. Supplemental Carb per se could not remedy the adverse effects of high CT.
采用2×3析因设计，研究了添加碳水化合物酶（Carb）和调质温度（CT）对饲喂大麦型日粮的1至21日龄肉鸡生长性能、养分利用率和肠道形态的影响，评估了2个Carb水平（0和150克/吨饲料）和3个CT水平（60、74和88°C）。总共使用了288只1日龄雄性肉鸡（8只/笼；6笼/处理）。Carb中内切-1,4-β-葡聚糖酶、内切-1,3(4)-β-葡聚糖酶和内切-1,4-β-木聚糖酶的活性分别为800 BGU/g、700 BGU/g和2700 XU/g。在第21天，收集回肠食糜以测定养分消化率。对于任何测试参数，Carb和CT之间均无显著交互作用。无论CT如何，添加Carb均使体重增加（WG；P<0.05），每增重饲料消耗（F/G；P<0.001）分别降低30克/只和6.5个百分点。与60°C和74°C调质的日粮相比，将CT提高到88°C降低了（P<0.05）WG，但提高了（P<0.05）F/G。无论CT如何，Carb分别提高（P<0.05）了淀粉消化率和表观代谢能（AMEn）1.15%和32千卡/千克。与60°C和74°C调质的日粮相比，88°C的CT降低了（P<0.05）干物质、氮、磷、总能和AMEn的消化率。与饲喂60°C调质日粮的肉鸡相比，饲喂88°C调质日粮的肉鸡淀粉消化率较低（P<0.05）。与60°C和74°C调质的日粮相比，88°C调质使空肠食糜粘度提高了（P<0.05）10.2%。总体而言，添加Carb可提高饲喂大麦型日粮肉鸡的WG、F/G、淀粉消化率和AMEn，与所采用的CT无关。将大麦型日粮在88°C下调质会损害肉鸡利用氮、淀粉、磷和能量的能力，从而使WG和F/G恶化。Carb和CT之间缺乏显著交互作用表明，无论是否添加Carb酶，高CT对肉鸡性能和养分利用率产生的负面影响都会发生。单独添加Carb无法弥补高CT的不利影响。
