Prophylaxis of Salmonella abortus ovis-induced abortion of sheep by a Salmonella typhimurium live vaccine.
A Salmonella typhimurium live vaccine with optimal level of attenuation for sheep, constructed by means of 'metabolic drift' mutations, was tested for its efficacy in preventing Salmonella abortus ovis-induced abortions. In two field trials in Kirgiziya, 78,000 to 100,000 first delivery sheep received a fully tolerated single dose of 10(9) c.f.u. live vaccine 2 months before to 4 months after insemination. Alternatively, they were immunized twice with commercial inactivated S. abortus ovis vaccine, or they served as non-immunized controls. The S. abortus ovis-induced abortion frequency in the controls was greater than or equal to 30%, in sheep immunized with inactivated vaccine greater than or equal to 11%. In flocks immunized with live vaccine, the S. abortus ovis-induced abortion frequency did not exceed 0.1%. Thus, use of 'metabolic drift' mutations for construction of stable vaccine strains optimally attenuated for the particular host species proved to be relevant to practice.
Linde
K
K
Institute of Medical Microbiology and Epidemiology, Leipzig University, Germany.
Bondarenko
V
V
Sviridenko
V
V
D000034:Abortion, Veterinary / Q000517:prevention & control*; D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology*; D005260:Female; D011247:Pregnancy; D012481:Salmonella Infections, Animal / Q000517:prevention & control*; D012486:Salmonella typhimurium / Q000276:immunology*; D012756:Sheep; D012757:Sheep Diseases / Q000517:prevention & control*; D014611:Vaccination
D001428:Bacterial Vaccines