【作者】 赵勇；

【导师】 王彦红； 严敏；

【作者基本信息】 扬州大学 ， 兽医硕士（专业学位）， 2022， 硕士

【摘要】 徐州水禽产业规模在江苏省乃至全国占有重要地位。徐州作为江苏省肉鸭的主产区和肉鹅的养殖聚集区,每年鸭、鹅的出栏量占比高达70%。随着畜牧养殖业的集约化规模不断发展,危害水禽的疫病也越来越多,越来越复杂,其中沙门氏菌病是造成企业损失的重要细菌病之一。抗生素药物被广泛用于沙门氏菌的治疗和预防,但由于抗生素长时间、超剂量和盲目使用,导致沙门氏菌对抗生素药物产生耐药性,甚至出现多重耐药性。因此,探索解决水禽规模养殖中对环境产生的污染问题、公共食品质量问题具有重要意义。本文主要研究了两个主要问题:一是围绕江苏省徐州地区有关鸭、鹅不同季节、不同月龄以及不同区域沙门氏菌进行科学系统的流行病学调查;二是养殖场中鸭或鹅源沙门氏菌耐药性,旨在为遏制江苏省徐州地区水禽产品沙门氏菌污染提供指导监测数据,为水禽养殖中合理使用抗生素、有效防控沙门氏菌病提供理论依据。试验分为以下2个部分:本试验对徐州地区部分水禽生产企业的沙门氏菌进行流行病学调查,同时对采集的病料进行沙门氏菌的分离鉴定。对采集的样本使用选择性培养基、生化鉴定与PCR等方法,将获得的沙门氏菌纯菌株进行血清型鉴定。研究结果表明:本试验共分离获得62株沙门氏菌,其中鸭源沙门氏菌分45株,鹅源沙门氏菌17株;从小于1月龄的鸭鹅样品中分离出44株,从大于1月龄的鸭鹅样品中分离出18株。62株分离菌血清学鉴定检测发现,共鉴定出5种血清型,33株分离菌为肠炎沙门氏菌,其中鸭源分离出30株,鹅源分离出3株;16株分离菌为鼠伤寒沙门氏菌,其中鸭源分离出4株,鹅源分离出12株;11株分离菌为印第安纳沙门氏菌,其中鸭源分离出10株,鹅源分离出1株;1株鹅源分离菌为海德堡沙门氏菌,1株鸭源分离菌为科特布斯沙门氏菌。本试验旨在系统研究徐州地区水禽重点养殖区域分离获得沙门氏菌的耐药情况。耐药性试验结果表明:分离菌株对氨苄西林的耐药率高达1 00%;对头孢曲松最为敏感,耐药性最低,耐药率为0。有40株出现多重耐药情况,多重耐药率为64.5%,耐药最多的沙门氏菌可以耐受6种类别的抗生素。选取对β-内酰胺类和氨基糖苷类耐药的38株菌株检测相应的9种耐药基因。其中,β-内酰胺类抗生素中TEM基因的检出率为92.11%,CTX-M基因的检出率为7.89%,OXA-1基因的检出率为15.79%,OXA-48基因的检出率为0,CMY基因的检出率为21.05%,ACC基因的检出率为18.42%。氨基糖苷类抗生素中aac(3)-Ia基因的检出率为0,aac(6)-Ib基因的检出率为13.16%,aadA基因的检出率为44.74%。同时携带2种或2种以上耐药基因的沙门氏菌高达94.7%(36株),本试验单株菌最多携带7个耐药基因,其中TEM与aadA基因联合于各种组合最为常见,共检测出17株(44.7%)。TEM和TEM+CTX-M+OXA-1+OXA-48+CMY+ACC等基因与药敏性的总符合率较高。综上所述,江苏省徐州地区水禽养殖场中有5种血清型,其中最常见的血清型为肠炎沙门氏菌,并对多种抗生素有耐药性,这与沙门氏菌本身携带的耐药基因有一定的联系。这些实验结果为江苏省徐州地区水禽养殖过程中沙门氏菌的综合防治提供理论依据。更多还原

【Abstract】 The waterfowl industry in Xuzhou occupies an important position in Jiangsu province and even in China.Xuzhou,as the main producing area of ducks and geese in Jiangsu Province,accounts for 70%of the annual output of ducks and geese.With the continuous development of the intensive scale of animal husbandry,more and more diseases of waterfowl are becoming complex,among which salmonellosis is one of the important bacterial diseases that cause enterprise losses.This is not only harmful to animal health and productivity,but also a serious threat to human health.Antibiotic are widely used in the treatment and prevention of Salmonella.However,due to long-term,over-dose and blind use of antibiotics,Salmonella develops resistance to antibiotic,even multiple antibiotic resistance.Therefore,it is significant to explore the environmental pollution and public food quality problems caused by large-scale waterfowl husbandry.This study mainly studied two main problems:to investigate scientific and systematic epidemiological of ducks and geese in Xuzhou,Jiangsu province in different seasons,ages and regions and to provide theoretical basis for rational use of antibiotics in waterfowl breeding and effective prevention and control of salmonellosis.This study contained the following two parts:In this study,the epidemiological investigation of Salmonella from some waterfowl production enterprises in Xuzhou was carried out,and Salmonella was isolated and identified from the collected diseased samples.The samples were selected for serotype identification by selective medium,biochemical identification and PCR.The results showed that sixty-two strains were isolated by culture medium,biochemical identification and PCR.Forty-five strains were isolated from ducks and seventeen from geese.Forty-four strains were isolated at less than 1 month of age and eighteen strains were isolated at greater than 1 month of age.Serological identification showed that five serotypes were identified.Thirty-three strains of Salmonella Enteritidis were isolated,including thirty strains from ducks and three strains from geese.Sixteen strains of Salmonella Typhimurium were isolated,including four strains from ducks and twelve strains from geese.Eleven Salmonella Indiana strains were isolated,including ten strains from ducks and one strain from geese.One Salmonella Heidelberg strain was isolated from goose and one Salmonella Kottbus strain was isolated from duck.This study was conducted to investigate the drug resistance of waterfowl farms in Xuzhou.The antibiotic resistance test results showed that the resistance rate to ampicillin was up to 100%.Ceftriaxone was the most sensitive and had the lowest drug resistance,with a drug resistance rate of 0.Forty strains were found to have multiple drug resistance,with a multiple drug resistance rate of 64.5%.The most resistant Salmonella strains could tolerate six classes of antibiotics.Nine drug resistance genes of 38 strains resistant to β-lactam and aminoglycoside were detected.The detection rates of TEM gene,CTX-M gene,OXA-1 gene,OXA-48 gene,CMY gene and ACC gene of β-lactam antibiotics were 92.11%,7.89%,15.79%,0,21.05%and 18.42%,respectively.The detection rates of aac(3)-Ia gene,aac(6’)-Ib gene and aadA gene of aminoglycoside antibiotics was 0,13.16%and 44.74%,respectively.The proportion of isolations containing three resistance genes was the highest(26.3%).As many as 94.7%(36 strains)of Salmonella had 2 or more resistance genes.In this study,a single strain carried up to 7 resistance genes,among which TEM combined with aadA gene was the most common,17 strains(44.7%)were detected.The genes that were more coincident with drug sensitivity of the isolates were TEM and TEM+CTX-M+OXA-1+OXA-48+CMY+ACC.In conclusion,there are five serotypes in waterfowl farms in Xuzhou,Jiangsu Province,among which the most common serotype is Salmonella enteritidis,which is resistant to a variety of antibiotics,which may be related to the drug resistance genes carried by Salmonella.These experimental results provide theoretical basis for comprehensive control of Salmonella in waterfowl breeding in Xuzhou,Jiangsu Province.更多还原