Epidemiologic aspects of bovine mastitis and its control in several dairy herds in southeastern China

Abstract

Our surveys indicated that the incidence of clinical mastitis ranged from 132 to 212 clinical quarter per 100 cows year −1 and the incidence of subclinical mastitis averaged 38.4% as determined with a reagent similar to CMT (e.g. Hangzhou Mastitis Test, HMT). Contagious pathogens were responsible for about 80% of the total bacterial isolates; environmental bacteria such as Escherichia coli and Streptococcus uberis accounted for only less than 10%. Herbal therapy was effective against both clinical and subclinical mastitis. Laser beam irradiation on certain acupoints also has been used to treat subclinical mastitis. Further research to confirm the efficacy of these two therapies under well-controlled conditions is required. Several dry-cow preparations have been formulated and tested in the field on the basis of bacteriologic findings. They were efficacious in eliminating existing bacterial infections and reducing clinical outbreaks during the dry period. Recent studies have revealed that incorporation of dry-cow therapy and teat dipping into the dairy management system can markedly reduce the incidence of clinical and subclinical mastitis.