عنوان مقاله [English]
Clostridium novyi is the pathogenic agent of the black disease, especially in sheep and rarely in other animals. The α toxin produced by C. novyi type B is major pathogenic agent of the disease. The economic loss of the black disease includes sheep deaths, depreciation of farms, and hygienic carcass-disposal challenges. The most efficient method to control the black disease, as an incurable disease, is vaccination. To this end, bacterin vaccine of Razi Vaccine and Serum Research Institute (RVSRI) are mainly used in Iran. In the current study, the pentavalent clostridial toxoid vaccine, containing C. novyi type B was compared to the black disease bacterin/toxoid vaccine of RVSRI. The study is going to detect immunogenical, biochemical and hematological changes in the blood of New Zealand rabbits before and after two administrations with three-week interval administrations. Two weeks after the last injection, the rabbits were challenged orally by the bacteria. Results showed a more significant immunogenicity of toxoid than bacterin/toxoid vaccines in rabbits. The hematological factors including white blood cells, red blood cells, hemoglobin, MCV (mean Cell Volume), MCH (mean cell hemoglobin), MCHC (mean cell hemoglobin concentration), and platelet showed no significant difference at day 50 (after bacterial challenge) during the immunization period between the case and control groups. The biochemical factors, such as creatinine, glucose, total protein, albumin, BUN (blood urea nitrogen), ALT (alanine aminotransferase), and AST (aspartate aminotransferase), were also measured. Results showed no significant difference between the case and control groups in none of them also (p<0.05).