title: [Trial, in a contaminated environment, of an attenuated lyophilized vaccine against S. abortus ovis abortion in sheep].
abstract: Merinos ewe-lambs from Arles formed part of a transhumant flock in which S. abortus ovis infection was enzootic. A lyophilized living vaccine was prepared from an attenuated mutant strain of Salmonella abortus ovis. About one third out of 450 ewe-lambs of the same flock received one subcutaneous injection of vaccine 1 to 3 months before fecundation; the other ewe-lambs were used as controls. No modification of behaviour was observed after vaccination. Three months later, serological post-vaccinal "H" agglutinins tested by a microtechnique could still be detected. According to observations during the lambing period, 25 (18.8%) out of the 133 vaccinated ewes and 55 (20.2%) out of the 272 controls were non-pregnant, 6 (4.5%) and 33 (12.9%) of each group lambed abnormally (P less than 0.02), and respectively 4 and 15 ewes excreted wild strains of S. abortus ovis. These results suggested the favourable effect of vaccination in an abortive environment caused by S. abortus ovis.
mesh_terms: D000034:Abortion, Veterinary / Q000517:prevention & control*; D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D001428:Bacterial Vaccines / Q000276:immunology*; D005260:Female; D005612:Freeze Drying; D006386:Hemagglutination Tests / Q000662:veterinary; D008297:Male; D011247:Pregnancy; D012475:Salmonella / Q000276:immunology*; D012481:Salmonella Infections, Animal / Q000517:prevention & control*; D012756:Sheep; D012757:Sheep Diseases / Q000517:prevention & control*; D014611:Vaccination / Q000662:veterinary; D014613:Vaccines, Attenuated / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D014613:Vaccines, Attenuated
vernacular_title: Essai en milieu contaminé d'un vaccin atténué lyophilisé contre l'avortement de la brebis du a S. abortus ovis.