Control of mastitis in the dairy herd by hygiene and management.

Abstract An examination has been made of the value of hygiene systems in the control of mastitis and how this control can be improved by changes in hygiene and milking machines and by better use of therapy. A comprehensive hygiene scheme for controlling mastitis has two objectives: prevention of intramammary infection during milking and prevention of infection between one milking and the next. Indirect evidence suggests that the latter objective is the more important. However, the complete prevention of the transfer of mastitis pathogens from cow to cow has not been found possible, even with a comprehensive hygiene system. Nevertheless, hygiene systems designed to prevent the transfer of pathogens and more particularly to eliminate residual contamination at the completion of milking have been shown to reduce the number of new infections by about half. The combination of such hygiene systems with effective antibiotic therapy, which reduces the duration of infection, generally resulted in a decrease of more than 50% in the incidence of infection within a year. It is probable that further reduction in the incidence of infection can be made by improving management techniques. But it is more likely that this will be achieved by improved methods of mechanical milking designed to prevent infection occurring during milking and by the use of better teat dips than by the development of more comprehensive hygiene systems.