出壳雏鸡感染病原菌的分析

Analysis of pathogenic bacteria of the infected chicks

为探究刚出壳雏鸡感染病原菌的种类,本研究对90只刚出壳的病弱雏鸡进行病理观察;从肝脏等器官分离细菌,提取分离株DNA,进行16S r RNA基因序列的扩增并测序,将测定结果与Gen Bank相应细菌株比对,结合菌落菌体形态进行鉴定。结果显示,病弱雏鸡腹围较大;解剖显示皮下胶冻样,卵黄吸收不良,肝土黄色;显微镜下显示肝充血,脂肪变性。从病弱雏鸡的肝脏分离出菌株56株,分离率为62.2%（56/90）。其中粪肠球菌分离率为46.4%（26/56）,大肠杆菌为16.1%（9/56）,金色葡萄球菌为14.3%（8/56）,奇异变形杆菌为8.9%（5/56）,鲍氏不动杆菌为5.3%（3/56）,沼泽考克氏菌为3.6%（2/56）,柠檬酸细菌属为1.8%（1/56）,无色杆菌为1.8%（1/56）,地衣芽胞杆菌为1.8%（1/56）。结果提示,刚出壳雏鸡感染的细菌为9种,主要有肠球菌、大肠杆菌和金黄色葡萄球菌。这为雏鸡细菌感染的防治奠定了基础。

Our study observed the pathological changes of 90 sick and weak chicks just emerging from the shell to explore the newly hatched chickens infected with the types of pathogens.We isolated the bacteria from liver and else organ,the DNA of the isolate was extracted,the 16 S r RNA gene sequence was amplified and sequenced,and the result was compared with the strain of bacteria in Gen Bank.We identified the isolates by combining the morphology of the colonies with the results of the comparison.In result,the sick and weak chick＇s abdominal circumference was larger.Through the anatomy,their abdominal subcutaneous jelly,yolk malabsorption and khaki liver were observed.Under the microscope,we observed that the liver was congested and fatty degeneration.A total of 56 isolates were isolated,with a separation rate of 62.2%（56/90）.The Enterococcus faecalis separation rate was 46.4%（26/56）,Escherichia coli separation rate was 16.1%（9/56）,Staphylococcus aureus separation rate was 14.3%（8/56）,Bacillus separation rate was 8.9%（5/56）,Acinetobacter baumannii separation rate was 5.3%（3/56）,Candida marshes separation rate was 3.6%（2/56）,Citrobacter separation rate was 1.8%（1/56）,Achromobacter separation rate was 1.8%（1/56）,and Bacillus licheniformis separation rate was 1.8%（1/56）.The results suggest that newly hatched chicks infected with 9 species of bacteria and the main pathogens are Enterococcus,Escherichia coli and Staphylococcus aureus.The above-mentioned results laid the foundation for the prevention and treatment of chick bacterial infection.