Relationship between rumen bacterial community and milk fat in dairy cows

Boxue Si; Kaizhen Liu; Guoxin Huang; Meiqing Chen; Jiyong Yang; Xufang Wu; Ning Li; Wenhao Tang; Shengguo Zhao; Nan Zheng; Yangdong Zhang; Jiaqi Wang

doi:10.3389/fmicb.2023.1247348

Relationship between rumen bacterial community and milk fat in dairy cows

Front Microbiol. 2023 Oct 11:14:1247348. doi: 10.3389/fmicb.2023.1247348. eCollection 2023.

Authors

Boxue Si^{1

2}, Kaizhen Liu^{1

2

3}, Guoxin Huang^{1

2}, Meiqing Chen^{1

2}, Jiyong Yang^{1

2}, Xufang Wu^{1

2}, Ning Li^{1

2}, Wenhao Tang^{1

2}, Shengguo Zhao^{1

2}, Nan Zheng^{1

2}, Yangdong Zhang^{1

2}, Jiaqi Wang^{1

2}

Affiliations

¹ State Key Laboratory of Animal Nutrition and Feeding, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
² Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
³ Henan International Joint Laboratory of Nutrition Regulation and Ecological Raising of Domestic Animal, College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, China.

Abstract

Introduction: Milk fat is the most variable nutrient in milk, and recent studies have shown that rumen bacteria are closely related to milk fat. However, there is limited research on the relationship between rumen bacteria and milk fatty. Fatty acids (FAs) are an important component of milk fat and are associated with various potential benefits and risks to human health.

Methods: In this experiment, forty-five healthy Holstein dairy cows with alike physiological and productive conditions were selected from medium-sized dairy farms and raised under the same feeding and management conditions. The experimental period was two weeks. During the experiment, raw milk and rumen fluid were collected, and milk components were determined. In this study, 8 high milk fat percentage (HF) dairy cows and 8 low milk fat percentage (LF) dairy cows were selected for analysis.

Results: Results showed that the milk fat percentage in HF group was significantly greater than that of the dairy cows in the LF group. 16S rRNA gene sequencing showed that the rumen bacterial abundance of HF dairy cows was significantly higher than that in LF dairy cows; at the genus level, the bacterial abundances of Prevotellaceae_UCG-001, Candidatus_Saccharimonas, Prevotellaceae_UCG-003, Ruminococcus_1, Lachnospiraceae_XPB1014_group, Lachnospiraceae_AC2044_group, probable_genus_10 and U29-B03 in HF group were significantly higher than those in the LF group. Spearman rank correlation analysis indicated that milk fat percentage was positively related to Prevotellaceae_UCG-001, Candidatus_Saccharimonas, Prevotellaceae_UCG-003, Ruminococcus_1, Lachnospiraceae_XPB1014_group, Lachnospiraceae_AC2044_group, probable_genus_10 and U29-B03. Furthermore, Prevotellaceae_UCG-001 was positively related to C14:0 iso, C15:0 iso, C18:0, Ruminococcus_1 with C18:1 t9, Lachnospiraceae_AC2044_group with C18:1 t9 and C18:1 t11, U29-B03 with C15:0 iso.

Discussion: To sum up, rumen bacteria in dairy cows are related to the variation of milk fat, and some rumen bacteria have potential effects on the deposition of certain fatty acids in raw milk.

Keywords: 16S rRNA gene sequencing; fatty acid composition; key bacteria; milk fat; rumen bacteria.

Grants and funding

This study was supported by the National Key R&D Program of China (2022YFD1301004), the State Key Laboratory of Animal Nutrition and Feeding (2004DA125184G2108), the Agricultural Science and Technology Innovation Program (ASTIP-IAS12) and Modern Agro-Industry Technology Research System of the PR China (CARS-36).