猪变形杆菌感染症的调查研究

AN INVESTIGATIVE STUDY ON INFECTION OF PROTEUS IN PIGS

1986年以来,我县某些猪场发生一种以“体温升高、呕吐、腹泻、咳嗽、气喘”为主要症侯的猪病,猪群发病率从28.7％～52.3％不等,病猪平均致死率17.5％。剖检病死猪见肺、肺门淋巴结、气管和小肠呈明显的病理性变化。从17头病猪的肺、肺门淋巴结、脾和肝分离到12株变形杆菌。这些菌能产生不耐热的肠毒素,对小白鼠都有致死作用,回归健康猪能得与自然病例同样的病症,并在发病后4天死亡。康复猪的血清对本菌的凝集价高达1∶80～640,从而确诊为猪的变形杆菌感染症。

The clinical disease with symptoms of fever, cough, asthma, diarrhea and vomiting was found on some pig farms. Mortality of the affected pigs on these farms was from 28.7% to 52.3% and on average 17.5% of the fatalities directly related to the sickness. Obviously pathological alterations could be observed in the lungs,small intestines, lymph nodes and bronchi of affected pigs. 12 strains of Proteus were isolated in 17 infected lungs and liver samples where bacterial cultivation was attempted. The Proteus isolated from cases could cause death of mice after celiac inoculation and produce LT enterotoxin as evidenced by the experiments. Attempts to infect healthy pigs with Proteus were undertaken to determine pathogenicity and experimental pigs showed similar clinical signs with death resulting 4 days after oral inoculation. Recovery from the infection was accompanied by the appearance of agglutination antibodies ( l:80-640 ) . These findings indicate pathogenesis of Proteus infection in pigs.