| Chicken colibacillosis is a common disease of chicken,which causes great loss to poultry raising.Antibacterial drugs are one of the important means to control the Chicken colibacillosis.The problem of bacterial resistances and drug residues were more and more serious in the global scope,China has gradually increased the control of the use of antibacterial drugs following the banning on the use of antibacterial drugs in the form of feed additives in EU.The limited use of antibacterial drugs in food animals will become an inevitable trend worldwide.Systemic inflammation is the main pathological change of the Chicken colibacillosis.According to SIRS theory,the intervention of inflammation and development is one of the key links in the treatment of chicken colibacillosis.Chinese traditional medicine can play a positive role in many kinds of diseases by intervention of inflammation and other ways,and has the advantages of low residual and resistance to drug resistance.Combined literature and the needs of production,this study constituted compound preparation with the Chinese traditional medicine which anti-inflammatory and anti-bacterial is excellen,evaluated the therapeutic effect on chicken colibacillosis,and explore the mechanism of treatment.The result had important significance in prevention and treatment of chicken colibacillosis.1.The sensitivity of the O2 type of chicken E.coli clinical isolates to 8 kinds of antibacterial drugs such as penicillin（amoxicillin,amoxicillin-carat acid）,cephalosporins（Cephalosporin）,aminoglycosides（gentamicin）,Tetracycline（Tetracycline）,quinolones（ciprofloxacin,enrofloxacin）was detected by K-B method and double dilution method.The ESBLs was detected by disc diffusion method.The bacteriostatic ring diameter and MIC of 8 kinds of antibacterial drugs was Amoxicillin（16.4±2.1mm,64μg/ml）,amoxicillin/caratacid（19.8±1.39mm,4μg/ml）,cefuroxime（22.9±0.56mm,1μg/mL）,gentamicin（15.3±0.22mm,32μg/ml）,tetracycline（12.3±1.42mm,32μg/mL）,doxycycline（10.9±0.9mm,32μg/mL）,ciprofloxacin（13.2±1.3mm,8μg/ml）,enrofloxacin（25.1±1.64mm,0.25μg/ml）.The bacteriostatic ring diameter differences between two pairs of tested substrates were all greater than5mm.The results showed that the O2 type of chicken E.coli clinical isolates was highly resistant to amoxicillin,tetracycline,gentamicin,doxycycline and ciprofloxacin and sensitive to amoxicillin-carat acid,Cephalosporin and enrofloxacin.It was the multiple drug resistant bacteria which producing ESBLs.2.The drug resistance genes carried by the plasmid of the O2 type of chicken E.coli clinical isolates were amplification by PCR.The showed that the O2 type of chicken E.coli clinical isolates carried an AmpC gene（CMY）,two ESBL genes（CTX-M,TEM）,two fluoroquinolones resistance genes（qnrC,qepA）,two aminoglycoside resistance genes（armA,rmtB）and two tetracycline resistant genes（tetA,tetB）.The results was basically consistent with the phenotype of drug resistance.It is suggested that the drug resistance of clinical isolates of the O2 type of chicken E.coli clinical isolates may be related to the drug resistance genes;3.The sensitivity of the O2 type of chicken E.coli clinical isolates to 10 kinds of traditional Chinese medicine was detected by plate punch method and double dilution method in test tube.The anti-inflammatory activity of 10 kinds of traditional Chinese medicine was detected by the method of mouse ear swelling induced by xylene.The results showed that the MIC,bacteriostatic ring diameter and swelling inhibition rate of 10 kinds of traditional Chinese medicine were houttuynia cordata（62.5mg/mL,9.8±0.15mm,31.19±0.06%）,coptis（7.81mg/mL,18.3±0.04mm,22.1±0.04%）,scute llaria baicalensis（62.5mg/mL,14.4±0.12mm,42.29±0.05%）,paniculata（31.25mg/mL,14.6±0.17mm,56.3±0.04%）,kuh-seng（15.63mg/mL,13.6±0.15mm,39.49±0.09%）,honeysuckle（31.25mg/mL,12.8±0.16mm,28.4±0.06%）,rhizoma atractylodis（>0.5g/L,6.8±0.22mm,36.19±0.1%）,licorice（62.5mg/mL,7.4±0.13mm,33.8±0.13%）,fructus forsythia（15.63mg/mL,16.5±0.24mm,47.49±0.05%）,radix isatidis（31.25mg/mL,12.4±0.1mm,33.5±0.1%）.The bacteriostasis function of the coptidis and forsythia is the best and paniculata and forsythia have the best anti-inflammatory effect.Coptidis,forsythia and paniculata were selected for compound Chinese traditional medicine;4.On the basement of median infective dose of the O2 type of chicken E.coli clinical isolates to chicken which detected by two-step method and artificial infection model of chicken colibacillosis,the study researched the best proportion of paniculata,coptis and forsythia by orthogonal test method and took overall response rate of the treatment of chicken colibacillosis as an indicator.The results showed that paniculata and coptis have significant effect on total efficiency（P<0.05）and forsythia is not significant.The optimal dose combination of three traditional Chinese medicines was andrographis 70g,coptis 70g and forsythia 50g;5.The sensitivity of the O2 type of chicken E.coli clinical isolates to compound Chinese traditional medicine was detected by plate punch method and double dilution method.The results showed that the bacteriostatic ring diameter and MIC of compound Chinese traditional medicine were16.3±0.11mm and 15.63mg/mL to the O2 type of chicken E.coli.It was suggested that the O2 type of chicken E.coli clinical isolates were sensitive to the compound Chinese traditional medicine.The antibacterial mechanism may be related to the destruction of bacterial cell wall and membrane and increase of cell membrane permeability;6.The therapeutical effect of compound Chinese traditional medicine on artificial infection model of chicken colibacillosis was detected.The results showed that the high-dose compound Chinesetraditionalmedicinecanimprovetherelativeweightgainrateoftest chickens（47.77%）,improve the cure rate（62.5%）and overall response rate（87.5%）of chicken colibacillosis,and reduce incidence rate（26.67%）.The high-dose of compound Chinese traditional medicine group is very significant（P<0.01）or significant（P<0.05）higher than the APEC group,and the difference is not significant compare with the antibiotic control group;7.The therapeutic mechanism of compound Chinese traditional medicine on chicken colibacillosis was researched preliminary.The results showed that compound Chinese traditional medicine could decrease the content and mRNA expression level of transcription factor TLR4,NF-κB,proinflammatory cytokines IL-8,TGF-β4 and immunoregulatory factor IFN–γin peripheral blood,and improve the content and mRNA expression level of IL-10 in peripheral blood,increase or decrease the immune organ index significantly（P<0.01）and the ratio of IFN-γ/IL-4compared with control group.It is suggested that compound Chinese traditional medicine can improve the chicken colibacillosis by intervening inflammation,improving the immune level and maintaining the immune balance of chicken.Conclusion:1.The O2 type of chicken E.coli clinical isolates were the multiple resistant bacteria of ESBLs producing,which were highly resistant to 5 kinds of antibiotics such as amoxicillin,tetracycline,doxycycline,gentamicin and ciprofloxacin.Drug resistance was related to the drug resistance gene carried by plasmid;2.The O2 type of chicken E.coli clinical isolates were sensitive to compound Chinese traditional medicine（andrographis 70g,coptis 70g and forsythia 50g）,the mechanism was related to the destruction of bacterial cell wall and membrane;3.Compound Chinese traditional medicine can significantly reduce the incidence of Chicken colibacillosis,improve the cure rate and efficiency of Chicken colibacillosis,improve the relative weight gain rate of Chicken in colibacillosis,and have therapeutic effect on chicken colibacillosis.The therapeutic effect of high dose compound Chinese traditional medicine is equivalent to compound amoxicillin and carat acid;4.Compound Chinese traditional medicine can affect the transcription and expression of inflammatory factors,and can intervene and regulate the inflammatory response and improve the immune function of test chickens;5.The therapeutic effect of compound Chinese traditional medicine on chicken colibacillosis is related to its anti-inflammatory,antibacterial and regulation of immunity.Reducing the level of inflammation can improve the symptoms of chicken colibacillosis,and controlling the occurrence and development of inflammation may be one of the important means to treat chicken colibacillosis. |
PDF Full Text Request