摘要
【目的】2023年4月山西太原某肉鸡场发生雏鸡精神沉郁、食欲不振、发病急、病程短、死亡率高的现象,试验旨在确定病死鸡病原菌感染情况并对其生物学特性进行研究,以期为该地区细菌感染疾病的防治提供参考依据。【方法】对病死雏鸡进行病理剖检观察,采用平板划线法将病死鸡心脏、肝脏、脾脏组织在无菌环境下接种于BHI琼脂培养基进行细菌分离培养,利用革兰染色观察分离株形态;通过生化特性鉴定、16S rRNA基因扩增测序、细菌特异性引物PCR扩增鉴定细菌种属,应用Mega 11.0软件构建系统进化树;通过药敏试验检测分离株对常见抗菌药物的敏感性,同时对其进行致病性分析。【结果】病死鸡剖检可见皮下水肿且有渗出液,心脏、肝脏、脾脏、胸肌有出血点。分离纯化获得12株分离株,其中8株在血琼脂培养基上出现明显的溶血现象,在麦康凯琼脂培养基不生长,革兰染色为紫色;3株在麦康凯琼脂培养基呈紫红色菌落且革兰染色为红色;1株呈透明白色菌落,革兰染色为红色。生化鉴定结果显示,分离株生化特性分别与金黄色葡萄球菌、大肠杆菌、奇异变形杆菌相符。8株分离株血浆凝固酶试验结果阳性,4株为阴性。16S rRNA基因PCR扩增测序结果显示,分离株分别与GenBank中的金黄色葡萄球菌、大肠杆菌、奇异变形杆菌的相似性达98%以上,分别命名为SA-1~SA-8、E1~E3、P1。细菌特异性基因PCR鉴定结果显示,在280、414、509 bp处出现单一明亮条带,与预期相符。药敏试验结果显示,分离株SA-1~SA-8对亚胺培南、米诺环素、头孢他啶均敏感,E1~E3对氟苯尼考、亚胺培南、米诺环素等敏感,P1对亚胺培南、庆大霉素、阿米卡星、氨苄西林等敏感。致病性试验结果显示,雏鸡单独感染以及混合感染3种分离菌,20 h内全部死亡,分离株均有较强的致病性。【结论】本研究成功分离获得8株�
【Objective】In April 2023,chicks in a broiler farm in Taiyuan,Shanxi province showed depression,loss of appetite,rapid onset,short course of disease,and high mortality.This experiment was aimed at determining the pathogenic bacteria infection of dead chickens and studying its biological characteristics,in order to provide reference for the prevention and control of bacterial infection diseases in this area.【Method】Pathological examination and observation were carried out on dead chickens.The heart,liver and spleen tissues of dead chickens were inoculated with BHI agar medium in sterile environment by plate streak method.The morphology of isolates were observed by Gram staining.The bacterial species were identified by biochemical characterization,16S rRNA gene and bacteria-specific primers PCR,and the phylogenetic tree was constructed by Mega 11.0 software.The sensitivity of the isolates to common antibiotics was detected by drug sensitivity test,and the pathogenicity of the isolates was analyzed.【Result】Subcutaneous edema and exudate were found in the necropsy of the dead chicken.There were bleeding points in the heart,liver,spleen and pectoral muscle.12 isolates were obtained by isolation and purification,8 of them showed obvious hemolysis on blood agar medium,but did not grow on MacConkey agar medium and the Gram staining was purple.3 isolates showed purplish red colonies in MacConkey agar medium and Gram staining was red.1 strain was transparent white colony,Gram staining was red.Biochemical identification results showed that the biochemical characteristics of the isolates were consistent with Staphylococcus aureus,Escherichia coli and Proteus mirabilis,respectively.The plasma coagulase test of 8 isolates was positive and 4 isolates were negative.The results of 16S rRNA gene PCR amplification and sequencing showed that the isolates were more than 98%similar to Staphylococcus aureus,Escherichia coli and Proteus mirabilis in GenBank,and were named SA-1 to SA-8,E1 to E3,and P1,respectively.PCR identifi
作者
谢常红
刘桂兰
王颖
任建乐
牛胜
赵宇军
范瑞文
田文霞
XIE Changhong;LIU Guilan;WANG Ying;REN Jianle;NIU Sheng;ZHAO Yujun;FAN Ruiwen;TIAN Wenxia(College of Veterinary Medicine,Shanxi Agricultural University,Taigu 030801,China)
出处
《中国畜牧兽医》
CAS
CSCD
北大核心
2024年第12期5549-5559,共11页
China Animal Husbandry & Veterinary Medicine
基金
山西省科技创新青年人才团队(202204051001022)
山西省现代农业产业技术体系建设专项资金(2021-07、2022-07、2023CYJST-09)
山西省1331工程(20211331-13)。
关键词
鸡
金黄色葡萄球菌
大肠杆菌
奇异变形杆菌
致病性
chicken
Staphylococcus aureus
Escherichia coli
Proteus mirabilis
pathogenicity
