The effects of cows' diet on microbiological quality of dairy products

Several studies have shown that supplementing dairy cows' diets with herbs has positive effects on their health, milk yield, and the quality of dairy products. Natural additives can be used for their antimicrobial effects, as a mean to reduce antibiotic usage to treat infections in animals. Additionally, it can be an effective strategy for decreasing methane emissions in ruminants. My thesis investigated the effects of herbs supplementation in cows’ diet on milk and cheese microbiological quality. The experiment was divided into two parts. In part I, a cohort of dairy cows was given total mixed ration (TMR), Canapa sativa supplementation, and Satureja hortensis supplementation, in rotation. In part II, dairy cows of another group were fed with total mixed ration, Galium odoratum supplementation, and Echinacea purpurea supplementation. Individual milk samples were collected from each cow and utilized for the production of experimental cheeses. The milk and cheese samples were microbiologically analysed using specific media. Canapa was the only supplementation that impacted the microbial community of milk. Satureja, Gallium, and Echinacea did not affect the microbial community in either milk or cheese, indicating their potential suitability as feed supplements for dairy cows, since they did not compromise the microbiological quality of milk and cheese.