The Separation And Identification Of Dairy Cow Mastitis And Drug Resistance Analysis In Coagulase Negative Staphylococcus

Staphylococcus aureus is one of the main pathogenic bacteria in dairy cow mastitis.With the development of the dairy farming and domestic recognition of cow disease control and prevention,the prevention and control of dairy cow mastitis levels increase,some changes have taken place in pathogenic bacteria types and advantage bacterium group.Abroad reported by coagulase negative staphylococcus(CNS or CoNS)caused by recessive mastitis and clinical mastitis is in rising trend,and some studies have found that caused by the bacterium mastitis often occur in breeding management good cattle farm.In recent years,It is also gradually to the attention of the domestic in the field of veterinary.Two dairy recessive mastitis cases to investigate gansu province in the CNS infections,and the resistance characteristics of the isolated bacteria.We did research:1.Using recessive mastitis diagnostic reagents(LMT)two scale dairy cows screening in lanzhou of gansu province surrounding,selection LMT screening results for strong positive(+ + +)cow milk area,milk sample was taken a total of 58.36 strains of coagulase-negative staphylococci were isolated by bacterial isolation,Gram staining,Contact enzyme test and plasma coagulase test.Then,16 strains of CNS were identified by 16 S rDNA sequencing and online Blast software analysis.To determine the separation of 36 strains for eight kind(CNS).Respectively,Staphylococcus schleiferi,staphylococcus haemolyticus,Staphylococcus sciuri,Staphylococcus epidermidis,Staphylococcus lugdunensis,Staphylococcus warneri,staphylococcus xylosus,Staphylococcus simulans.The isolation rates were 47.22%,25.00%,13.88%,2.77%,2.77%,2.77%,2.77%,2.77%.Description,Staphylococcus schleiferi and staphylococcus haemolyticus of the CNS mainly caused by recessive mastitis in the two dairy cows in Gansu Province.2.Twenty kinds of antimicrobial agents were selected and the drug sensitivity test was carried out on 36 CNS by K-B method.The results show,36 strains of isolates showed a certain resistance phenotype,resistance to Penicillin,fusidic acid,clindamycin,gentamycin,tetracycline,erythromycin and amoxicillin were 30.56%,19.44%,13.88%,13.88%,11.11%,11.11%,8.3%,respectively,Sensitive to cefoxitin,oxacillin,cefepime,rifampicin,vancomycin,linezolid,nitrofurantoin.The resistance rates of 17 strains of Staphylococcus schleiferi to Penicillin,tetracycline,amoxicillinand clindamycin were 23.52%?23.52%?11.76%?11.76%.respectively.9 strains of staphylococcus haemolyticus were resistant to ciprofloxacin,penicillin,gentamicin,amoxicillinResistant rates were 44.44%?33.33%?33.33%?11.11%.The resistance rates of Staphylococcus aureus to fusidic acid,clindamycin and gentamicin were 100.00%,40.00% and 20.00%,respectively.Further detection of 36 CNS drug resistance genes.The results showed,the detection rate of resistance genes of 36 strains of coagulase-negative staphylococci to blaZ was 63.88%,the detection rate of rpoB was 55.55%,the detection rate of resistance gene of aacA-aphD was 19.44%,and the resistance of ermA ermB ermC The detection rate of drug resistance was 0.005%,5.55% and 16.66% respectively.The detection rate of vanA was 5.55%,and the detection rate of fusB and tetK,tetM and drug resistance were 0.00%.The positive rates of fusB,blaZ,ermB and ermC,vanA in 17 strains of Staphylococcus aureus were 88.23%,58.82%,11.76% and 29.41%,5.28% respectively.In 9 strains of Staphylococcus aureus blaZ,vanA The positive rates of rpoB,blaZ and aacA-aphD in staphylococcus aureus were 80.00%,40.00% and 40.00%,respectively.The positive rates of rpoB,blaZ and aacA-aphD were 66.66%,66.66% and 11.11% respectively.The results showed that CNSs with resistant phenotype did not necessarily carry the relevant drug resistance genes,and the strains carrying the relevant drug resistance genes did not necessarily show the relevant resistance phenotype.