ABSTRACT

1. The purpose of this research was to investigate the effects of supplementing an emulsifier (de-oiled soybean lecithin (DSL)) in a low metabolisable energy (ME) diet on growth performance, nutrient digestibility, carcase characteristics, intestinal morphology, blood metabolites, and antioxidant status in growing turkeys.

2. A total of 480 one-day-old turkeys were assigned to one of four dietary treatments with of eight replicates of 15 birds each. Experimental treatments included a basal diet (BE) with commercially recommended levels of ME, a reduced energy diet (RE) with 0.42 MJ/kg reduction in dietary ME content, the RE diet + 1 g/kg DSL (DSL-1), and RE + 2 g/kg DSL (DSL-2).

3. After 112 days, the body weight, average daily gain, and feed:gain in turkeys fed the supplemented for BE diets were better (P < 0.05) than in those fed RE, and those fed diet DSL-2 had the best performance. Although the RE diet decreased abdominal fat and relative liver weight (P < 0.05), compared to the BE diet, and supplementation with either level of DSL did not influence these variables.

4. There were linear increases (P < 0.05) in fat digestibility, nitrogen-corrected apparent ME, and duodenal villus height, villus height/crypt depth ratio, and villus surface area in LE diet supplemented with DSL. From the jejunal morphology, crypt depth was decreased by DSL-supplemented diets (P < 0.05).

5. Serum triglyceride, total cholesterol, and malondialdehyde concentrations were lower, whereas the serum superoxide dismutase activity was greater for the DSL-2 group compared to the BE and RE groups (P < 0.05).

6. The findings suggested that, while low-ME diets impaired turkey growth performance, dietary supplementation of DSL could reverse such impacts of these diets. The DSL-supplemented diet at the inclusion level of 2 g/kg was advantageous over both BE and RE diets in terms of intestinal morphology, lipid profile, and antioxidant status in growing turkeys.

摘要

1. 本研究的目的是研究在低代谢能 (ME) 日粮中添加乳化剂（脱油大豆卵磷脂 (DSL)）对生长性能、营养消化率、胴体特征、肠道形态、血液代谢物的影响和生长火鸡的抗氧化状态。

2. 总共 480 只 1 日龄火鸡被分配到四种饮食处理中的一种，每组 15 只火鸡重复 8 次。实验性治疗包括具有商业推荐水平的 ME 的基础饮食 (BE)、具有 0.42 MJ/kg 饮食 ME 含量减少的低能量饮食 (RE)、RE 饮食 + 1 g/kg DSL (DSL-1)，以及RE + 2 克/千克 DSL (DSL-2)。

3. 112天后，饲喂BE日粮的火鸡体重、平均日增重和饲料：增重优于饲喂RE的火鸡（P < 0.05），饲喂DSL-2日粮的火鸡表现最好. 尽管与 BE 饮食相比，RE 饮食降低了腹部脂肪和相对肝脏重量（P < 0.05），但补充任一水平的 DSL 均不会影响这些变量。

4.添加DSL的LE日粮中脂肪消化率、氮校正表观ME、十二指肠绒毛高度、绒毛高度/隐窝深度比和绒毛表面积呈线性增加（P < 0.05）。从空肠形态来看，添加 DSL 的日粮降低了隐窝深度（P < 0.05）。

5.与BE和RE组相比，DSL-2组血清甘油三酯、总胆固醇和丙二醛浓度较低，而血清超氧化物歧化酶活性较高（P < 0.05）。

6. 研究结果表明，虽然低 ME 日粮会损害火鸡的生长性能，但日粮中添加 DSL 可以逆转这些日粮的这种影响。在生长火鸡的肠道形态、脂质分布和抗氧化状态方面，添加 2 g/kg 的 DSL 日粮优于 BE 和 RE 日粮。