BIO Web of Conferences (Jan 2024)
Clinical trial results of an associated vaccine against cattle clostridiosis and escherichiosis
Abstract
In veterinary practice, gastrointestinal diseases of newborn calves, caused by the association of pathogenic bacteria, in particular Clostridium perfringens and Escherichia coli, are often observed. The results of our research have shown that in the Volga Federal District of the Russian Federation, anaerobic enterotoxemia in newborn calves is most often caused by Clostridium perfringens serotypes A, C, D. For the specific prevention of this form of pathology, an associated vaccine has been developed containing inactivated antigens of Clostridium perfringens serotypes A, C, D and Escherichia coli, which produce adhesion factors K99 and A20. Clinical trials of the effectiveness of the vaccine on cattle were carried out in 3 large agricultural enterprises of the Republic of Tatarstan for the production of milk, permanently dysfunctional for clostridiosis and escherichiosis of newborn calves. Disease prevention began with the immunization of pregnant cows and heifers 60 days before the expected calving. The animals were vaccinated twice with an interval of 14 days at a dose of 10 cm3. Calves obtained from immunized cows were vaccinated twice subcutaneously at a dose of 3 cm3 at the age of 18- 20 days. A total of 3156 cows and heifers were vaccinated in three dairy complexes. It was found that the associated vaccine is harmless for deepwalled cows and heifers, does not cause post-vaccination complications. Immunization of animals in the last months of pregnancy contributes to the accumulation of specific antibodies in colostrum, the intake of which provides passive protection of the newborn calf from infection with Cl. perfringens and E. coli bacteria.