Isolation And Identification Drug Resistance Analysis Of Pathogen Of Dairy Cow Mastitis In Shanghai Area

Objective: dairy cow's breast health directly affects the quality and safety of dairy products,and the pathogenic microorganism is the main factor that causes dairy cow mastitis.In order to understand the feeding and management of some standardized dairy farms in Shanghai,the contamination of major pathogenic bacteria in milk and the drug resistance rate,it provides a rational basis for the prevention and clinical diagnosis and treatment of cow mastitis in dairy farms.Methods: cows from 71 large-scale dairy farms in Shanghai were randomly sampled,and 71 samples of diseased cow's milk were collected through field investigation.The pathogenic bacteria were isolated,cultured and purified by line method,and then identified by biochemical and molecular biological methods.The main pathogenic bacteria(gram-positive bacteria and gram-negative bacteria)were isolated by dilution method of microbroth.Results:1.According to the investigation,all the 71 representative dairy farms in Shanghai have been able to carry out standardized management,regular disinfection and standard milking operation,which greatly reduced the invasion of pathogenic microorganisms in the milking process.Dairy farms are equipped with full-time veterinarians,USES the DHI(cow population improvement)determination technology to judge cows healthy,timely elimination of cured beef cattle farm collected amount of total and milking cow restock mostly in 0-499 scale,milk production 0 t-5 t,5 t-10-20 t t,10 t,more than 20 t pastures are evenly distributed,and most clinical mastitis and invisibility mastitis dairy occurrence are more optimistic,very few serious ranch type of mastitis.The survey found that the dairy farm management in the range of 1000 ~ 3000 was the most standardized and reasonable.2.In this experiment,71 samples were collected from large-scale dairy farms in Shanghai,and the target bacteria were identified: staphylococcus aureus,enterococcus faecalis,escherichia coli and klebsiella.The separation rate of enterococcus faecalis was 7.0%(5/71),klebsiella was 11.3%(8/71),escherichia coli was 15.5%(11/71),and staphylococcus aureus was 16.9%(12/71).3,staphylococcus aureus isolates are low or even no drug resistance,resistance to ampicillin,amoxicillin in enterococcus-clavulanic acid,cephalosporins thiamethoxam injunctions,doxycycline,rifampin and vancomycin and ciprofloxacin,and sulfanilamide different oxazole and compound new Ming min rate rate is higher,60%-100%,of cefalotin completely resistant,resistant rate of 100%,followed by penicillin,benzene Westwood,erythromycin,clindamycin and gentamicin,percentages are 60%,e.coli,only show the resistance of cefalotin,Klebsiella to cephalosporin thiamethoxam injunctions,beauty e.faecalis,streptomycin,kanamycin,fluorine benzene nicol,ciprofloxacin,polymyxin E and the sensitivity is high and the sensitive rate of 62.5%-100%,to ampicillin,gentamicin,tetracycline,sulfanilamide different oxazole and compound new Ming resistance performance,severity drug resistance to ampicillin =sulfanilamide different oxazole = gentamicin(75%)> tetracycline(62.5%)> compound new Ming(50%).4,staphylococcus aureus,without multiple drug resistance of enterococcus faecalis resistance results mainly focus on the three kinds of drugs,of 4 kinds of drug resistant,resistant to 5 kinds of drug resistance and 6 kinds of drug resistance,multiple drug-resistant e.coli results are mainly concentrated in 3,6 and 9,e.coli and klebsiella multi-resistant situation is most serious,klebsiella mainly concentrated in the 5,6,8 and10 resistance;Escherichia coli is resistant to 9 or 10 antimicrobial agents.The multiresistance of each strain was mainly concentrated in 3,5 and 6 resistance,among which 4 strains of enterococcus faecalis,5 strains of klebsiella and 3 strains of escherichia coli were 12 strains,accounting for 33.33% of the total number of4 isolates.Conclusion: staphylococcus aureus,enterococcus faecalis,escherichia coli and klebsiella bacteria were found in the fresh milk of large-scale dairy farms in some areas of Shanghai.Escherichia coli,klebsiella,multiple drug resistance is more serious,the use of antibiotics should be standardized;Cefotifume,ciprofloxacin,amoxicillin-clavulanate antibiotics can be recommended in this area,combined with the actual situation of the dairy farm to take preventive and medication measures,standardized and rational drug use,effectively curb the emergence of multiple drug resistance,for the prevention and treatment of cow mastitis to provide reference basis.