Analysis Of Bacterial Infection And Drug Resistance Of Isolated Bacteria In Clinically Pathogenic Porcine

In order to further understand the common bacterial infections in clinically infected pigs,the drug sensitive characteristics of bacteria,and the carrying status of common bacterial drug-resistance genes,148 strains of pathogenic bacteria were isolated from clinically infected pigs and the following tests were conducted:1.A total of 337 pathogenic swine samples from 113 pig farms in various regions of Hunan Province were subjected to bacterial isolation and identification.Results 44 E.coli isolates,35 SS,14 HPS,5 APP,5 Pm,8 SE,7 Staphylococcus,4 ERY,and 26 clinically rare pathogenic bacteria were isolated..It shows that the most common bacteria isolated from clinically affected pigs are E.coli,SS,HPS,APP,Pm,ERY,SE,Staphylococcus and so on.2.Select theoretically effective drugs for different types of isolates,and then use the paper method to analyze all the isolates for drug sensitivity analysis.The results showed that all isolated E.coli strains had the highest resistance rates to doxycycline,streptomycin,and ampicillin,reaching 97.8% and 100%,respectively;conditional gram-negative pathogens that are not clinically common are completely resistant to streptomycin,ampicillin,and amoxicillin;the resistant rate of Haemophilus parasuis to streptomycin was 90.9%;all isolated Gram-positive bacteria(Swine Streptococcus,pig erysipelas,etc.)to Lincomycin completely resistant to mycophenolate;all staphylococci are completely resistant to erythromycin and lincomycin.70.9% of the bacteria had more than double resistance,53.4%of the bacteria had more than 4 resistance.However,most bacteria have higher sensitivity to ceftriaxone,enrofloxacin,and amikacin.The detection results of drug resistance genes showed that the detection rates of sulfa,tetracyclines,and chloramphenicol were relatively high.The isolated E.coli strains contained plasmids and the detection rate of their plasmid resistance genes was very high.The highest detection rate of Salmonella resistance gene was sulfonamide resistance gene,and the detection rate of TEM-1 gene on its plasmid reached 75%.Staphylococcus was low in the carrying rate of drug resistance genes detected in this study.Only the presence of TEM-1 and ParC genes was detected.3.Infection tests on mice with Streptococcus suis and Haemophilus parasuis revealed that the simultaneous injection of the two bacteria could cause the disease to be more serious than that of a type of bacteria.At the same time,it was found that when a large amount of one of the bacteria was injected,mice were injected with dexamethasone at the same time,and the mice had a slower onset and a lower mortality rate.This may be due to the fact that dexamethasone inhibits the acute inflammatory response of the body in the early stages of bacterial invasion,leading to the onset of serious non-injection drug use.The blood was collected from the Haemophilus parasuis and the control mice that had not died after the challenge.Serum concentrations of the antibodies were tested after dilution.The results showed that injection of dexamethasone had no significant effect on the production of mouse antibodies in the presence of a large number of live bacteria injections.