Kim Minseok, Park Tansol, Jeong Jin Young, Baek Youlchang, Lee Hyun-Jeong
Animal Nutrition & Physiology Team, National Institute of Animal Science, Wanju 55365, Korea.
Department of Animal Science, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Korea.
Animals (Basel). 2020 Apr 19;10(4):712. doi: 10.3390/ani10040712.
This study demonstrated the potential effects of the rumen microbiota on the deposition of intramuscular fat, known as marbling. Previous studies on fatty acid metabolism in beef cattle have mostly focused on biohydrogenating rumen bacteria, whereas those on the overall rumen microbiota-to understand their roles in marbling-have not been systematically performed. The rumen microbiota of 14 Korean beef cattle (Hanwoo), which showed similar carcass characteristics and blood metabolites but different marbling scores, were analyzed by 16S rRNA gene sequencing. The rumen samples were grouped into two extreme marbling score groups of host animals as follows: LMS, marbling score≤ 4 or HMS, marbling score ≥7. Species richness tended to be higher in the HMS group, whereas the overall microbiota differed between LMS and HMS groups. RFP12, Verrucomicrobia, , Porphyromonadaceae, and were differentially abundant in the HMS group, whereas was abundant in the LMS group. Some marbling-associated bacterial taxa also contributed to the enrichment of two lipid metabolic pathways including "alpha-linolenic acid metabolism" and "fatty acid biosynthesis" in the HMS microbiome. Taxonomic drivers of fatty acid biosynthesis, particularly in the rumen microbiome of high-marbled meat, could thus be further studied to increase the intramuscular fat content.
本研究证明了瘤胃微生物群对肌内脂肪沉积（即大理石花纹）的潜在影响。先前关于肉牛脂肪酸代谢的研究大多集中在瘤胃生物氢化细菌上，而关于整个瘤胃微生物群（以了解它们在大理石花纹形成中的作用）的研究尚未系统开展。对14头韩国肉牛（韩牛）的瘤胃微生物群进行了分析，这些牛的胴体特征和血液代谢产物相似，但大理石花纹评分不同，采用16S rRNA基因测序法进行分析。瘤胃样本按照宿主动物的大理石花纹评分分为两个极端组：低大理石花纹评分组（LMS），大理石花纹评分≤4；高大理石花纹评分组（HMS），大理石花纹评分≥7。HMS组的物种丰富度往往更高，而LMS组和HMS组的整体微生物群存在差异。RFP12、疣微菌门、卟啉单胞菌科和 在HMS组中丰度不同，而 在LMS组中丰度较高。一些与大理石花纹相关的细菌类群也促成了HMS微生物组中包括“α-亚麻酸代谢”和“脂肪酸生物合成”在内的两条脂质代谢途径的富集。因此，可以进一步研究脂肪酸生物合成的分类驱动因素，特别是在高大理石花纹肉的瘤胃微生物组中，以增加肌内脂肪含量。
