Clinical mastitis (visible inflammation of the udder) is a painful disease which mostly is caused by udder infection with bacteria and is the most common cause of antibiotic treatment in Swedish dairy cows. The long-term aim of the project is to improve animal welfare and the economy of the herds by producing new treatment guidelines resulting in reduced and more efficient use of antibiotics, which in turn leads to fewer injections and fewer new cases of mastitis due to reduced risk of spread of udder infections between cows.
The project will investigate if local treatment with antibiotics (penicillin) in the udder to a large extent can replace systemic treatment with penicillin via intramuscular injections (present standard treatment) for bacteria that are relatively easy to cure. This would reduce the total amount of penicillin used from 70 to 17 grams per case for a normal size dairy cow. For bacteria that are more difficult to cure, as they are prone to cause chronic udder infections with increased risk of spread to other cows in the herd, we want to investigate if systemic treatment can be combined with local treatment to improve bacteriological cure. This would result in a small increase in the amount of penicillin used per case, but a significant reduction of the total amount used if this regimen can prevent new cases of mastitis by reducing the number of cows with chronic infection.