摘要
Several studies have evaluated the effects of live yeast supplementation on rumen microbial population; however, its effect on differential microbial genes and their functional potential has not been described. Thus, this study applied shotgun metagenomic sequencing to evaluate the effects of live yeast supplementation on genetic and functional potential of the rumen microbiota in beef cattle. Eight rumen-cannulated Holstein steers were randomly assigned to two treatments in a cross-over design with two 25-day experimental periods and a 10-day wash-out between the two periods. The steers were housed in individual pens and fed 50% concentrate-mix and 50% red clover/orchard hay ad libitum. Treatments were (1) control (CON; basal diet without additive) and (2) yeast (YEA; basal diet plus 15 g/d of live yeast product). Rumen fluid samples were collected at 3, 6, and 9 h after feeding on the last d of each period. Sequencing was done on an Illumina HiSeq 2500 platform. Dietary yeast supplementation increased the relative abundance of carbohydrate-fermenting bacteria (such as Ruminococcus albus, R. champanellensis, R. bromii, and R. obeum) and lactate-utilizing bacteria (such as Megasphaera elsdenii, Desulfovibrio desulfuricans, and D. vulgaris). A total of 154 differentially abundant genes (DEGs) were obtained (false discovery rate < 0.01). Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation analysis of the DEGs revealed that 10 pathways, including amino sugar and nucleotide sugar metabolism, oxidative phosphorylation, lipopolysaccharide biosynthesis, pantothenate and coenzyme A biosynthesis, glutathione metabolism, beta-alanine metabolism, polyketide sugar unit biosynthesis, protein export, ribosome, and bacterial secretory system, were enriched in steers fed YEA. Annotation analysis of the DEGs in the carbohydrate-active enzymes (CAZy) database revealed that the abundance of genes coding for enzymes belonging to glycoside hydrolases, glycosyltransferases, and carbohydrate binding modules were enriched in steers fed YEA. These results confirm the effectiveness of a live S. cerevisiae product for improving rumen function in beef steers by increasing the abundance of cellulolytic bacteria, lactic acid-utilizing bacteria, and carbohydrate-active enzymes in the rumen.
摘要译文
几项研究评估了补充活酵母对瘤胃微生物种群的影响。然而，尚未描述其对差异微生物基因及其功能潜力的影响。因此，本研究应用shot弹枪宏基因组测序来评估补充活酵母对肉牛瘤胃微生物群遗传和功能潜力的影响。在交叉设计中，将八只瘤胃空心的荷斯坦牛ers随机分配给两种处理，在两个周期之间进行两个为期25天的实验期，并进行10天的冲洗。将ers牛放在单独的围栏中，随意饲喂50％的浓缩饲料和50％的红三叶草/果园干草。治疗方法为（1）对照（CON；不添加添加剂的基础饮食）和（2）酵母（YEA；基本饮食加每日酵母产品15微克/天）。在每个时期的最后一天进食后，分别在3、6和9 h收集瘤胃液样品。在Illumina HiSeq 2500平台上进行测序。膳食酵母补充剂增加了碳水化合物发酵细菌（例如鲁米诺球菌，R。champanellensis，R。bromii和R. obeum）和乳酸的相对丰度，而细菌利用了细菌（例如大球藻，脱硫脱硫弧菌和脱硫D. vulgaris）。 。总共获得154个差异丰富的基因（DEGs）（错误发现率<0.01）。京都基因与基因组百科全书（KEGG）对DEG的注释分析揭示了10种途径，包括氨基糖和核苷酸糖代谢，氧化磷酸化，脂多糖生物合成，泛酸和辅酶A生物合成，谷胱甘肽代谢，β-丙氨酸代谢，聚酮糖单位生物合成，蛋白质输出，核糖体和细菌分泌系统均富含饲喂YEA的公牛。对碳水化合物-活性酶（CAZy）数据库中DEGs的注释分析表明，富含糖的水解酶，糖基转移酶和碳水化合物结合模块的酶的基因编码丰富了公牛YEA。这些结果证实了活啤酒酵母产品通过增加瘤胃中的纤维素分解细菌，乳酸利用细菌和碳水化合物活性酶的丰度，可以改善牛肉ste中的瘤胃功能。
Ibukun M. Ogunade[1]Jerusha Lay[1]Kenneth Andries[1]Christina J. McManus[1]Frederick Bebe[1]. Effects of live yeast on differential genetic and functional attributes of rumen microbiota in beef cattle[J]. Journal of Animal Science and Biotechnology, 2019,10(1)