In Vitro Antibacterial Activities of the Tibetan Herbal Medicines Against the Staphylococcus Isolated From Mastitis of Guanzhong Dairy Goat

Background: Dairy goat mastitis is one of the most significant disease with effect on Guanzhong dairy goat breeding. The purpose of this study was to screen the pathogenic bacteria from milk samples of the mastitis of Guanzhong dairy goat and evaluate the antibacterial activities of six Tibetan herbal medicines, including Swertia bimaculata , Gentiana urnula , Uncaria rhynchophylla , Aconitum flavum , Dracocephalum tanguticum and Lagotis brachystachy on Staphylococcus isolated. Results: Fifty-two bacteria species, and a total of 149 different isolates were identified from 55 milk samples, and Staphylococcus was the predominant species as it accounted for 36.91% (55/149) of the identified isolates, and S. aureus (26/55) was the majority of the Staphylococcus isolates. Histopathological examination showed that obvious pathological changes were observed in the liver, kidney and lung tissues of the mice infected with S. aureu s. Most of the Staphylococcus isolates expressed the multidrug resistance except for S. aureus and S. hemolyticus . The water extracts of several Tibetan medicinal plants exhibited distinguished in vitro antibacterial activities for the Staphylococcus, especially the S. aureus as well as the MDR isolates. Lagotis brachystachy has the most significant antibacterial activity, and followed by the Aconitum flavum , Uncaria rhynchophylla , Swertia bimaculata , and Dracocephalum tanguticum , while the Gentiana urnula showed the weaker inhibitory effects to the tested Staphylococcus isolates. Conclusion: This study indicated that Tibetan herbal medicines could be a potential candidate for the treatment the mastitis of dairy goat in clinical application.