The correlation and mechanism between rumen microbiota disturbance and mastitis in dairy cows

Abstract

Background: Mastitis, which is a highly prevalent disease in dairy cows and economically costly to the dairy industry worldwide, is commonly believed to be caused by local infection of the mammary gland. Recently, studies have suggested that the gut microbiota plays an important role in the development of cow mastitis, yet the mechanisms linking the gut microbiota to mastitis remain unclear. This study assessed the effects and mechanisms of rumen microbiota on mastitis based on the subacute rumen acidosis (SARA) model induced by feeding a high-concentration diet (HCD) to Holstein cows . Results: Lipopolysaccharides (LPS)-derived from the rumen translocated into the blood and then accumulated in the mammary glands by damaging the integrity of the blood-milk barrier and induced an inflammatory response in the mammary glands of SARA cows. Furthermore, elevation of the abundance of Stenotrophomonas was one of the endogenous factors to induce mastitis during cows suffering SARA. Finally, we found that rumen microbiota imbalance induced by SARA resulted in increased severity to mastitis by inhibiting the clearance of pathogens from the mammary glands in SARA cows. Conclusions: This study identifies rumen microbiota dysbiosis and LPS translocation from the rumen to the mammary gland as important factors to induce mastitis in cows. In addition, rumen microbiota imbalance increased mastitis susceptibility by inhibiting the ability of the mammary glands to clear out pathogens. Our studies provide a basis for novel therapeutic strategies that exploit the gut microbiota in cow mastitis.

Effect of Heat Stress on Rumen Microbial Diversity and Fermentation Pattern in Buffalo

“…Genus Stenotrophomonas, unclassified genus (family: Moraxellaceae), and Achromobacter of the phylum Proteobacteria appeared after exposure to heat stress in the present study. Increased abundance of Stenotrophomonas indicated an increase in pathogenic population in the rumen ecosystem as Stenotrophomonas population was reported to be correlated with mastitis and subacuteruminal acidosis in dairy cows [64]. Similarly, an increase in abundance of Moraxellaceae has been reported during subacuteruminal acidosis [65] which implies that increase in Moraxellaceae during heat stress was due to a decrease in pH; however, a minimal change was observed in the bacterial population responsible for lowering pH in the present study.…”

Healthy Cattle Microbiome and Dysbiosis in Diseased Phenotypes

“…Recent studies suggested that gut microbiome dysbiosis played an important aetiological role in intra-mammary infections (IMI) [94]. In a study by Ma Chen et al, 2018, it was proposed that the intestinal microbiota can induce mastitis.…”

“…One study found out that the overproduced lipopolysaccharides (LPS) by the rumen, moved into the blood and disturbed the blood-milk barrier by accumulating in the mammary glands. Consequently, inducing IMI in subacute rumen acidosis (SARA) infected cows, and increases the severity of mastitis infection [94]. Ruminal short-chain fatty acids (SCFAs) have a protective effect on the blood-milk barrier, and therefore against IMI [97] (Table 1).…”

Healthy Cattle Microbiome and Dysbiosis in Diseased Phenotypes

“…Recent studies suggested that gut microbiome dysbiosis played an important aetiological role in intramammary infections (IMI) [92]. In a study by Ma Chen et al 2018, it was proposed that the intestinal microbiota can induce mastitis.…”

“…One study found out that the overproduction of lipopolysaccharides (LPS) by the rumen, translocated into the blood and disturbed the blood-milk barrier by accumulating in the mammary glands. Consequently, inducing IMI in subacute rumen acidosis (SARA) infected cows, which eventually increased the severity of mastitis infection [92]. Ruminal short chain fatty acids (SCFAs) have a protective effect towards the blood-milk barrier, and therefore against IMI [95].…”