Bovine mastitis, a significant inflammatory response of the mammary gland, adversely impacts dairy cow health and milk production globally. Klebsiella pneumoniae (K. pneumoniae) has been identified as the important bacterium causing mastitis in dairy cows. However, the mechanism remains to be fully elucidated. In this study, we established the mastitis model induced by K. pneumoniae which demonstrated significantly lower milk fat and protein synthesis, accompanied by mitochondrial dysfunction. Mechanistically, K. pneumoniae caused inflammation and triggered mastitis by activating folliculin interacting protein 1 (FNIP1), impairing mitochondrial function, and inhibiting the synthesis of milk lipids and milk proteins. In conclusion, this study demonstrated that FNIP1 is involved in the inflammatory response of dairy cow mastitis caused by K. pneumoniae infection through regulating mitochondrial function, which is expected to be a new target for the prevention and control of bovine mastitis.

Read the full article in the Journal of Animal Science.