Isolation And Identification Of Bovine Mastitis Pathogenic Bacteria And The Drug Susceptibility Testing To The Pathogens

The intension of this study is to find out the leading pathogens causing bovine subclinical and clinical mastitis and effective antibiotic treatments to certain pathogens; also Chinese traditional medicine susceptibility is tested.In a certain herd(90 cows), the incidence of the subclinical and clinical mastitis was collected by an Epidemiology investigation. The bacteria causing bovine subclinical and clinical mastitis were isolated and identified. The reasch of drug susceptibility testing was also operated in vitro. As the investigation showed, the cow infection rate of clinical mastitis is 15.56%(14 of 90); that of subclinical mastitis is 57.78%(52 of 90). The GVFBXquarter infection rate of clinical mastitis is 5.41%(18 of 333) and that of subclinical mastitis is 32.73%(109of333).59 bacterial strains were isolated from 10 milk samples of subclinical mastitis.including staphylococci(22 of 59,37.29%), streptococci(23 of 59,38.98%)and Gram-negative bacilli(14 of 59,23.73%). 275 bacterial strains were isolated from 11 milk samples of clinical mastitis, Including staphylococci(79 of 275, 28.73%), streptococci(167 of 275, (50.73%) and Gram-negative bacilli(29 of275,10.54%). The leading pathogens(accounting for 18.64% of totle) of subclinical mastitis are Staphylococcus aureus, Streptococcus agalactiae amd Escherichia coli; that of clinical mastitis is Streptococcus agalactiae accounting for 37.09% which is much higher than any other pathogens.The drug susceptibility testing indicates that Quinotones, Amikacin,Kita sermonic, Cephazolin and Erythromycin have good inhibitory effect on Staphylococcus. All these three kinds of Staphylococcuus take on high sensitive effect. Enrofloxacin, Ampicillimn and Erythromycin have good inhibitory effect on Streptococcus.Four Staphylococcus strains take on high sencitivity. Amikacin and Kita sermonic have the best inhibitory effect on Gram-negative bacilli. The Chinese traditional medicine susceptibility testing shows that the compound Chinese traditional medicine I has inhibitory effect on the leading pathogens; the compound Chinese traditional medicine II plays an important role on the inhibition of the mastitis caused by Staphylococcus; however, the compound Chinese traditional medicine III doesn't show good effect, while the further research about the compound Chinese traditionalmedicine I and II should be continued in order to apply to clinical medicine.Above all, Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli are the main pathogens causing bovine subclinical mastitis; the bovine clinical mastitis is usually caused by Streptococcus agalactiae. Antibiotics such as Enrofloxacin, Erythromycin and Kita sermonic show effective on treatment; the preparation of Chinese traditional medicine has great potential on bovine mastitis treatment and should be widely spread.