What are the two most important causative agents of mastitis?

The primary causative agents of mastitis in dairy cows are indeed Staphylococcus aureus and Streptococcus agalactiae. Staphylococcus aureus is particularly significant because it can cause persistent infections, leading to chronic mastitis and is known for its ability to form biofilms, making treatment difficult. It can also be transmitted between cows, which poses a risk in herds, resulting in economic losses due to decreased milk production and increased veterinary costs. Streptococcus agalactiae, on the other hand, is a contagious pathogen associated specifically with mastitis and can lead to severe infections.

Together, these two organisms represent some of the most common and impactful agents of mastitis, affecting both the health of the cows and the quality of milk produced. Their prevalence and the challenges they pose reinforce the importance of effective mastitis management and prevention strategies within dairy operations.