复方中草药超微粉防治鸡致病性大肠杆菌病的研究

发布时间：2018-02-26 20:27

  本文关键词： 鸡 致病性E.coli 复方中草药超微粉 防治试验　出处：《河北科技师范学院》2017年硕士论文　论文类型：学位论文

【摘要】：为了筛选出有效的防治鸡致病性大肠杆菌病复方中草药超微粉,本试验以筛选的致病性最强优势血清型地方流行株QH1(O_(78))建立病理模型,进行单味中草药体外抑菌试验,利用鸡致病性大肠杆菌病的中兽医辨证理论观点,选择体外抑菌敏感单味中草药作为主药,根据各种单味中草药配伍中君、臣、佐、使的药理性质组合成复方中草药超微粉,通过体外抑菌试验和人工感染动物试验筛选出抑菌效果好的复方中草药超微粉,用人工感染14、49日龄雏鸡致病性E.coli验证其复方中草药超微粉防治效果,并检测复方中草药超微粉对人工感染14日龄雏鸡致病性E.coli后的免疫机能指标、血清生化指标,揭示其作用机理;通过对雏鸡的急性、亚慢性毒性试验评价复方中草药超微粉使用的安全性。本研究的试验结果如下:1.从秦皇岛地区不同养鸡场分离鉴定出56株E.coli,其中46株分离株为致病性E.coli,占分离菌株的82.1%;46株致病性E.coli属于11种血清型,以O_(78),O89,O142及O1为优势血清型;46株致病性E.coli携带16种不同毒力基因。根据E.coli分离菌株的动物致病性试验、血清型及毒力基因携带情况,筛选出了致病性最强优势血清型地方流行株QH1(O_(78))。对1,14,49日龄雏鸡的LD50分别为3.16×106 CFU/mL,1.07×107 CFU/m L,5×108 CFU/mL。2.单味中草药体外抑菌试验,利用平板琼脂打孔法和改良微量二倍稀释-平板法,从26种中草药中筛选出对鸡致病性E.coli的地方株QH1(O_(78))、QH2(O89)、QH4(O1)均敏感的中草药金银花、黄连、乌梅、五味子,其抑菌圈直径在20.3~22.7mm之间,MIC在15.65~31.25 mg/mL之间。3.复方中草药超微粉的筛选,利用鸡致病性大肠杆菌病的中兽医理论辨证理论观点与各种单味中草药配伍中的药理性质组合5个复方中草药,通过体外抑菌和人工感染动物性试验,筛选出了抑菌效果最好的复方Ⅲ。4.复方中草药超微粉(复方Ⅲ)对人工感染14,49日龄雏鸡致病性E.coli防治试验的结果显示,C组(1%禽用头孢噻呋钠)和D~F组(复方Ⅲ添加量分别为1.5%、2.0%、2.5%)的死亡率明显低于B组(阳性对照组),E组和F组的预防与治疗效果均高于B组与C组,其中以E组对14,49日龄雏鸡致病性大肠杆菌病防治效果最好,保护率分别为86.7%,90.0%;治愈率分别为92.9%,90.0%;有效率分别为89.7%,93.3%。5.复方中草药超微粉(复方Ⅲ)对人工感染14日龄雏鸡致病性E.coli血清中生化指标、免疫机能的检测,A~F组分别在试验后的第7,14,21天采血分离血清进行相关指标检测。结果显示,E组(2.0%复方Ⅲ添加)效果最好,能提高血清中免疫蛋白IgG,IgM,IgA水平;提高血清中LZM,TP,GLB的含量;降低血清中GOT,TG,TC,BUN,UA含量。6.急性性毒性试验结果显示复方Ⅲ对雏鸡是无急性毒副作用,最大耐受量超过25g/(kg·d)。亚慢性毒性试验结果显示,复方Ⅲ对雏鸡长期服用是安全的。
[Abstract]:In order to screen out the superfine powder of Chinese herbal medicine for the prevention and treatment of chicken pathogenic Escherichia coli, the pathological model was established by screening the most dominant serotype local epidemic strain QH1 / OF78, and the bacteriostasis test of single Chinese herbal medicine was carried out in vitro. Based on the theory of Chinese veterinarian syndrome differentiation of pathogenic Escherichia coli disease in chicken, the Chinese herbal medicine with single Chinese herbal medicine was selected as the main medicine in vitro. According to the compatibility of each kind of Chinese herbal medicine with Zhong Jun, Chen and Zuo, the pharmacological properties were combined into compound Chinese herbal medicine ultrafine powder. In vitro bacteriostasis test and artificial infection animal test were used to screen the superfine powder of compound Chinese herbal medicine with good bacteriostasis effect. The pathogenicity E.coli of 14 ~ 49 days old chicks infected artificially was used to verify the control effect of the compound Chinese herbal medicine ultrafine powder. The immune function index, serum biochemical index and mechanism of compound Chinese herbal medicine ultrafine powder on 14 day old chickens infected by artificial infection were detected, and the mechanism of their action was revealed. The results of this study are as follows: 1. 56 strains of E. coli were isolated from different chicken farms in Qinhuangdao area, of which 46 strains were pathogenicity E.coli, accounting for the isolation of bacteria. There are 11 serotypes in pathogenic E. coli. 46 strains of virulence E. coli carried 16 different virulence genes. According to the animal pathogenicity test, serotype and virulence gene carrying status of E. coli isolates. The most virulent serotypic endemic strain QH1 / L was screened out. The LD50 of the chicken was 3.16 脳 106CFU / mL1.07 脳 107CFU / mL1.07 脳 107CFU / mL / mL, 5 脳 108CFU / mL-1 respectively. The bacteriostasis test of single Chinese herbal medicine in vitro was carried out by using plate Agar punching method and modified microdilution plate method. The Chinese herbal medicines Flos Lonicerae, Coptis chinensis, Fraxinus chinensis, Fructus Schisandrae and Schisandra chinensis, which are sensitive to the local strain QH1 / OH7, QH2O89, QH4O1, have been screened from 26 Chinese herbal medicines. The inhibitory circle diameter of Flos Lonicerae, Coptis chinensis, Fructus Schisandra and Fructus Schisandrae is between 20.32mm and 22.7mm, and the MIC is 15.653.31.25 mg/mL. Five compound Chinese herbal medicines were combined by using the theory of Chinese veterinary medicine dialectical theory of pathogenic Escherichia coli disease in chicken and the pharmacological properties of each kind of Chinese herbal medicine. The in vitro bacteriostasis and artificial infection of animal were tested. Compound 鈪，

本文编号：1539588