Effects of Fat Type and Exogenous Bile Acids on Growth Performance, Nutrient Digestibility, Lipid Metabolism and Breast Muscle Fatty Acid Composition in Broiler Chickens

脂肪类型和外源性胆汁酸对肉鸡生长性能、营养物质消化率、脂肪代谢和胸肌脂肪酸组成的影响

作者：耿仕夏、张宇新、曹爱智、刘颖、狄玉婷、李军涛、娄倩倩、张丽英

Simple Summary: Exogenous BAs can serve as emulsifiers and when supplemented in broiler chicken diets, they can facilitate the absorption of fat and fat-soluble nutrients. As far as we know, no research compared the impacts of BAs on broiler chickens fed with animal fat and vegetable oil. Therefore, the current research aimed to explore the impacts of fat type and BAs on growth performance, nutrient digestibility, lipid metabolism, and breast muscle fatty acids composition in broiler chickens. The results showed that the positive impacts of BAs were obvious for broiler chickens fed diets with lard compared with soybean oil.

简单总结：外源性胆汁酸在肉鸡日粮中补充时，可以促进脂肪和脂溶性营养物质的吸收。据我们所知，没有研究比较胆汁酸对饲喂动物油和植物油对肉鸡的影响。因此，本研究旨在探讨脂肪类型和胆汁酸对肉鸡生长性能、营养消化率、脂质代谢和胸肌脂肪酸组成的影响。结果表明，与豆油相比，饲喂猪油日粮的肉鸡同时添加胆汁酸的积极影响更为明显。结果表明：胆汁酸对饲喂猪油和豆油日粮的肉鸡有显著的积极影响。

Abstract: The current study aimed to explore the effects of fat type and exogenous bile acids (BAs) on growth performance, nutrient digestibility, lipid metabolism, and breast muscle fatty acids compo-sition in broiler chickens. A total of 432 one-day-old Arbor Acres male broilers were stochastically distributed to a 2 × 2 factorial design comprised of two fat types (soybean oil and lard) and two levels of BAs (0 and 80 mg/kg) included in diets, totaling 4 treatments of 6 replicate pens with 18 chicks per replicate pen. Compared with treatments with soybean oil, dietary inclusion of lard increased the digestibility of ether extract (EE) in diets and the percentage of breast muscle on d 42, and increased the level of serum triglycerides and decreased serum alanine aminotransferase (ALT) activity on d 21 (p < 0.05). The level of saturated fatty acids, monounsaturated fatty acids (MUFAs), and the n-6 to n-3 polyunsaturated fatty acids ratio in breast muscle were also increased (p <0.05) when feeding lard versus soybean oil. Dietary supplementation with BAs elevated average daily gain and reduced the ratio of feed to gain at d 0?21 and 0?42, significantly (p < 0.05). The digestibility of EE in diets and the percentage of breast muscle on d 42 were also increased by BAs (p < 0.05). Serum total cholesterol content as well as the percentage of abdominal fat on d 42, and ALT activity on d 21 were decreased when BAs were fed (p < 0.05). The concentration of total fatty acids, saturated fatty acids, and MUFAs of breast muscle were decreased by BAs. These results indicate that BAs can increase growth performance and nutrient digestibility, elevate carcass characteristics, and improve lipid metabolism, and their effects on nutrient digestibility and carcass characteristics were more pronounced in broiler chickens fed diets with lard.

摘要：

本研究旨在探讨脂肪类型和外源性胆汁酸对肉鸡生长性能、营养物质消化率、脂质代谢和胸肌脂肪酸组成的影响。432 只 1 日龄的 AA雄性肉鸡被随机分配到 2 × 2 因子设计中，包括两种脂肪类型（豆油和猪油）和两种水平的胆汁酸（0 和 80 mg/kg），共 4个处理6 个重复，每个重复18 只肉鸡。

与大豆油相比，日粮添加猪油增加了粗脂肪的消化率和第42天的胸肌百分比，并增加了第21天的血清甘油三酯水平，降低了血清谷丙转氨酶（ALT）活性 (p < 0.05)。

当饲喂猪油与大豆油时，胸肌中饱和脂肪酸、单不饱和脂肪酸 (MUFA) 和 n-6 与 n-3 多不饱和脂肪酸的比例也显著增加 (p < 0.05)。

日粮中添加胆汁酸可显著提高 0-21 天和 0-42 天的平均日增重，降低料肉比（p < 0.05）。日粮中 EE 的消化率和第 42 天的胸肌百分比也因胆汁酸而增加（p < 0.05）。饲喂胆汁酸后，第 42 天的血清总胆固醇含量以及腹部脂肪百分比和第 21 天的 ALT 活性均降低（p < 0.05）。胆汁酸降低了胸肌总脂肪酸、饱和脂肪酸和MUFAs的浓度。

这些结果表明，胆汁酸可以提高生长性能和营养物质消化率，改善脂质代谢，提高胴体品质。并且在添加猪油的日粮中，胆汁酸对肉鸡养分消化率和胴体特性的影响更为显著。