Effects of Dietary Tributyrin on Growth Performance,Serum Biochemical Indices,Immune Function and Antioxidant Capacity of Juvenile Yellow Catfish (Pelteobagrus fulvidraco)北大核心CSCD

This experiment was conducted to investigate the effects of dietary tributyrin on growth performance, serum biochemical indices, immunity function and antioxidant capacity of juvenile yellow catfish (Pelteobagrus fulvidraco). A total of 480 juvenile yellow catfish with an initial body weight of (5.53±0.02) g were selected and randomly divided into 4 groups with 3 replicates in each group, and 40 fish in each replicate. Four isonitrogenous and isolipid experimental diets were fed with 0 (G0), 500 (G1), 1 000 (G2) and 2 000 mg/kg (G3) triglyceride, respectively. The experiment lasted for 56 days. The results showed as follows: 1) weight gain rate and feed efficiency rate in G2 group were significantly higher than those in other groups (P<0.05). The fatness in G1 group was significantly lower than that in G0 and G3 groups (P<0.05), but there was no significant difference between G1 group and G2 group (P>0.05). 2) The serum glucose content in G3 group was significantly higher than that in G1 and G2 groups (P<0.05), and there were no significant differences in the serum contents of total protein, albumin, globulin, triglyceride, urea nitrogen and the activities of alanine aminotransferase and aspartate aminotransferase among all groups (P>0.05). 3) Compared with G0 group, serum lysozyme activity in G1, G2 and G3 groups was significantly increased (P<0.05), serum alkaline phosphatase activity in G1 and G2 groups was significantly increased (P<0.05), and serum immunoglobulin M content in G2 group was significantly higher than that in G3 group (P<0.05). There was no significant difference in serum complement C3 content among all groups (P>0.05). 4) Compared with G0 group, serum total antioxidant capacity in G1 group was significantly increased (P<0.05), and serum super-oxide dismutase activity in G1, G2 and G3 groups was significantly increased (P<0.05). The serum catalase activity in G3 group was significantly higher than that in G0, G1 and G2 groups (P<0.05), but there were no significant differences in serum glutathione peroxidase activity, glutathione and malondialdehyde contents among all groups (P>0.05). In conclusion, dietary supplementation of 500 to 2 000 mg/kg triglyceride can significantly improve non-specific immune and antioxidant capacity of yellow catfish, and dietary supplementation of 1 000 mg/kg triglyceride can significantly improve weight gain rate and feed efficiency of yellow catfish. Combined with the comprehensive evaluation of growth performance, serum immunity and antioxidant indexes, the optimal supplemental level of triglyceride in yellow catfish diet is 1 000 mg/kg. © 2023 Authors. All rights reserved.     

饲料中添加丁酸梭菌或丁酸钠对大口黑鲈生长性能、血清生化指标、肝脏免疫和抗氧化能力的影响

本试验旨在研究饲料中添加丁酸梭菌（CB）或丁酸钠（SB）对大口黑鲈（Micropterus salmoides）幼鱼生长性能、血清生化指标、肝脏免疫、抗氧化能力以及低氧应激的影响。试验配制3种等氮（50%）和等脂（9%）的饲料,分别为基础饲料（Con）、基础饲料中添加10 mL/kg的CB的试验饲料、基础饲料中添加1.0 g/kg的SB的试验饲料。选取体重为（5.02±0.01） g的大口黑鲈360尾,随机分为3组,分别饲喂3种饲料,每组3个重复,每个重复40尾鱼,开展8周的养殖试验,随后进行低氧应激试验。结果显示：1）与Con组相比,CB组增重率（WGR）和蛋白质沉积率（PDR）显著提高（P<0.05）,CB组饲料系数（FCR）显著降低（P<0.05）。与Con组相比,CB组肠体比（ISI）显著增加（P<0.05）。2）与Con组相比,SB组血清中碱性磷酸酶（AKP）活性和甘油三酯（TG）含量显著降低（P<0.05）,CB组和SB组血清尿素氮含量显著降低（P<0.05）,SB组血清葡萄糖（GLU）含量显著升高（P<0.05）。3）与Con组相比,饲...     

丁酸钠的生物学功能及其在动物生产中的应用

丁酸钠可作为抗生素良好的替代品，根据生产工艺的不同，其可分为包被丁酸钠和非包被丁酸钠。作为一种绿色功能性添加剂，丁酸钠能够通过在肠道中分解释放丁酸促进肠道上皮细胞生长发育、改善肠道绒毛形态结构、增强肠道消化吸收和损伤修复能力，同时还可调节肠道酸性环境、抑制有害病原体繁殖和促进耐酸有益菌增殖；丁酸钠能够抑制促炎因子表达、增强机体免疫能力、降低肝脏功能损伤和保护肝脏健康，并通过降低丙二醛含量、激活核因子E2相关因子2(Nrf2)通路增强机体抗氧化能力；此外，丁酸钠还可调节脂质代谢，减少脂肪堆积。本文在国内外相关研究的基础上，重点阐述丁酸钠在调节动物肠道健康、免疫力、抗氧化能力和脂质代谢等方面的生物学功能及其在猪、禽、反刍动物、水产动物养殖中的应用，旨在为丁酸钠在动物生产中的研究和合理应用提供科学依据。     

β-葡聚糖的生物学功能及在水产养殖中的应用

β-葡聚糖来源广泛，主要存在于植物和微生物细胞壁中，由葡聚糖单体构成，具有多种结构，因其侧链残基种类和数量的不同而具有多种生物学功能，如通过降低炎症相关基因表达及提高免疫因子的表达发挥调节免疫的作用；通过减少脂质的产生和吸收发挥调节脂质代谢的作用；通过提高抗氧化酶、自由基、超氧阴离子的清除活性及激活Nrf2信号通路、上调抗氧化基因的表达来增强机体的抗氧化能力，发挥抗氧化作用；通过增强缺氧耐受性及提高抗氨氮应激能力、能量代谢和抗氧化酶基因的表达等发挥抗应激作用。自抗生素禁用以来，β-葡聚糖在水产动物中的研究和应用逐渐深入，β-葡聚糖在预防水产动物疾病和减少抗生素使用等方面发挥着重要作用。在水产养殖中，β-葡聚糖可通过提高消化酶活性、改善肠道结构、优化肠道菌群及增强非特异性免疫力来提高水产动物生长性能，β-葡聚糖的联合使用比添加单一种类的免疫刺激剂具有更好的免疫效果。作者就β-葡聚糖的结构特征、生物学活性、作用机制及在水产动物中的应用进行了综述，并对β-葡聚糖今后的发展方向进行了展望，为实现水产动物生态健康养殖提供材料。     

饲料添加L-精氨酸或N-氨甲酰谷氨酸对杂交鳢肠道黏膜形态和肠道菌群的影响

[目的]本实验旨在研究饲料添加精氨酸或NCG对杂交鳢（Channa maculata ♀×Channa argus ♂）肠道黏膜形态和肠道菌群的影响。[方法]选用初始体重（22.02±0.02） g的杂交鳢450尾。随机分为3个组，每组3个重复，每个重复50尾，分别饲喂基础饲料以及在基础饲料中添加0.60% L-精氨酸（Arginine, Arg）、0.03% N-氨甲酰谷氨酸（N-Carbamylglutamate, NCG）三种实验饲料，饲养周期为56天。[结果]结果显示：与对照组相比，饲料中添加0.60% Arg显著提高了杂交鳢终末重、特定生长率（P＜0.05），添加0.60% Arg或0.03% NCG显著提高了杂交鳢的蛋白质沉积率（P＜0.05），显著降低了饲料系数（P＜0.05）。与对照组相比，饲料添加Arg或NCG可显著提高杂交鳢肠道中肠、后肠肌层厚度，中肠绒毛宽度，NCG组后肠肌层厚度显著高于对照组与Arg组（P＜0.05）。各实验组肠道黏膜层、肌层结构清晰紧密、黏膜层绒毛丰富，对照组与Arg组出现少量绒毛顶部上皮与固有层间隙增宽，NCG组却未见明显异常。饲料添加精氨酸可显著提高杂交鳢肠道菌群物种丰富度，Chao指数与Ace指数显著高于对照组与NCG组（P＜0.05）。与对照组相比，NCG组显著提高厚壁菌门及变形菌门的丰度，但NCG组梭杆菌门丰度显著降低，与Arg组具有显著差异性（P＜0.05）。[结论]由此得知，饲料中添加Arg在生长性能方面优于添加NCG，但饲料添加NCG可以显著增加肠道厚壁菌门等有益菌门丰度，维持肠道内环境稳定，其作用效果优于补充Arg。