histopathological and biochemical evaluation of tetravalent enterotoxemia vaccine effects in balb/c

clostridium perfringens, one of the most important pathogens is the main causative agent of enterotoxemia in farm animals. vaccination is the most effective prevention method against diseases caused by clostridium perfringens. one of the most important testes regarding vaccine quality control is toxicity test (measuring residual toxin). the evaluation of test results was done regarding to clinical factors and mortality rate of mice that received vaccine. the present study was aimed to evaluate the toxicity test of enterotoxemia vaccine clinically, histopathologically and biochemically (bs, bun and creatine) examinations. in this study, 21 balb/c mouse with an average weight of 25 grams were used and divided into 3  equal groups including group 1 (vaccine), group 2 (control) and group 3 (culture medium). health factors and mortality rate of all mice was checked before and during the survey. groups 1 and 3 received 0.5 ml enterotoxaemia vaccine and culture medium (without bacterium) subcutaneously, respectively and group 2 (control) did not receive any material. after 48 hrs blood sampling was done and blood biochemical factors were evaluated. finally, animals were necropsied and histopathological studies on 3 groups were performed.  the stata10 software and anova and scheffe tests were used for statistical analysis. for analysis of histopathological results, fisher test were used. histopathological results showed focal gliosis in brain tissue in the vaccinated group (except in two cases), control group (except one) and culture medium group (except one). liver tissues had mild lymphocytic hepatitis and mild hepatocellular degeneration and necrosis in all samples of vaccinated group, 6 samples of control group and 3 samples of culture medium group. kidneys in all groups showed a mild degree of epithelial changes except of 1 case in vaccinated group and 2 cases in culture medium group. heart, spleen, intestine and lungs were normal in all groups. results showed no significant difference between groups. also, biochemical results showed a significant difference in amount of bs between group 1 and groups 2 and 3, as well as the amount of urea between group 1 and 3 (p < 0.05). the results of the study indicate that enterotoxemia vaccine didn’t cause a significant injury in tested mice.