Liu Mingjian, Wang Zhijun, Sun Lin, Wang Yu, Li Junfeng, Ge Gentu, Jia Yushan, Du Shuai
Key Laboratory of Forage Cultivation, Processing and High Efficient Utilization of Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, China.
Key Laboratory of Grassland Resources of Ministry of Education, Inner Mongolia Agricultural University, Hohhot, China.
Front Microbiol. 2023 Jul 13;14:1197059. doi: 10.3389/fmicb.2023.1197059. eCollection 2023.
The objectives of this study were to evaluate the effects of different forage proportions in the fermented total mixed ration (FTMR) on growth performance, muscle fatty acid profile, and rumen microbiota of lambs.
Thirty 6-month-old small tail Han sheep × Ujumqin lambs with initial body weight (BW) of 27.8 ± 0.90 kg were selected for the test and divided into two groups of 15 sheep in each treatment (three pens per treatment and five lambs per pen) according to the principle of homogeneity. Two isoenergetic and isonitrogenous diets were formulated according to the NRC. The diet treatments were designed as (1) OH treatment containing 25% alfalfa hay and 35% oat hay, and (2) AH treatment containing 35% alfalfa hay with 25% oat hay. The forage-to-concentrate ratio for both diets was 65: 35 (DM basis). Three replicates were randomly selected from each treatment to determine growth performance, fatty acid profile and rumen bacterial communities in lambs.
Results revealed no statistically significant ( > 0.05) differences in dry matter intake and average daily gain between the two diet groups. Cholesterol and intramuscular fat were significantly ( > 0.05) higher in the AH group, while no statistically significant difference ( > 0.05) was found in pH24 value. The muscle fatty acid compositions of lambs were obviously ( < 0.05) influenced by the diet treatments. Compared with the OH group, the C16:1, C17:0, and C20:3n6 contents were higher ( < 0.05) in the AH group, whereas the content of C18:1n9c, C20:1, C18:3n3, and C22:6n3 was obviously ( < 0.05) increased in the OH group. The monounsaturated fatty acid (MUFA) contents were significantly higher in the OH group, whereas no significant differences ( > 0.05) were detected in saturated fatty acid (SFA) and polyunsaturated fatty acid (PUFA) contents among the two diet treatments. Bacterial composition was generally separated into two clusters based on principal coordinate analysis, and the OH group had a higher Shannon index. The relative abundance at the genes level of the was obviously ( < 0.05) increased in the AH group and the relative abundances of , and were obviously ( < 0.05) enriched in the OH group. Integrated correlation analysis also underscored a possible link between the muscle fatty acid compositions and significantly altered rumen microbiota.
Overall, oat-based roughage in FTMR could promote a beneficial lipid pattern in the Longissimus lumborum muscles of lambs. These findings provide a potential insight into diet effects on fatty acid profile and the rumen microbiome of lambs, which may help make decisions regarding feeding.
本研究旨在评估发酵全混合日粮（FTMR）中不同草料比例对羔羊生长性能、肌肉脂肪酸谱和瘤胃微生物群的影响。
选择30只6月龄小尾寒羊×乌珠穆沁杂交羔羊，初始体重（BW）为27.8±0.90 kg用于试验，并根据同质原则将其分为两组，每组15只羊（每个处理三个围栏，每个围栏五只羔羊）。根据美国国家研究委员会（NRC）配制两种等能量、等氮日粮。日粮处理设计为：（1）OH处理，含25%苜蓿干草和35%燕麦干草；（2）AH处理，含35%苜蓿干草和25%燕麦干草。两种日粮的草料与精料比例均为65:35（干物质基础）。从每个处理中随机选取三个重复，以测定羔羊的生长性能、脂肪酸谱和瘤胃细菌群落。
结果显示，两组日粮的干物质摄入量和平均日增重无统计学显著差异（>0.05）。AH组的胆固醇和肌内脂肪显著较高（>0.05），而pH24值无统计学显著差异（>0.05）。日粮处理对羔羊肌肉脂肪酸组成有明显影响（<0.05）。与OH组相比，AH组的C16:1、C17:0和C20:3n6含量较高（<0.05），而OH组的C18:1n9c、C二十：1、C18:3n3和C22:6n3含量明显增加（<0.05）。OH组的单不饱和脂肪酸（MUFA）含量显著较高，而两种日粮处理的饱和脂肪酸（SFA）和多不饱和脂肪酸（PUFA）含量无显著差异（>0.05）。基于主坐标分析，细菌组成一般分为两个聚类，OH组的香农指数较高。AH组中该基因水平的相对丰度明显增加（<0.05），而OH组中、和的相对丰度明显富集（<0.05）。综合相关性分析也强调了肌肉脂肪酸组成与瘤胃微生物群显著变化之间可能存在的联系。
总体而言，FTMR中以燕麦为基础的粗饲料可促进羔羊腰大肌中有益的脂质模式。这些发现为日粮对羔羊脂肪酸谱和瘤胃微生物组的影响提供了潜在的见解，这可能有助于做出饲养决策。
