COMPARISON OF 3 BIOLOGICAL ASSAYS FOR THE DETECTION OF TOXIGENIC PROPERTIES OF BORDETELLA-BRONCHISEPTICA ASSOCIATED WITH ATROPHIC RHINITIS

The toxigenic properties of Bordetella bronchiseptica strains associat ed with clinical atrophic rhinitis were compared using three biologica l assays: the guinea pig skin test, the mouse spleen atrophy and the s uckling mice mortality assay. Forty one sick pigs were cultured and, i n 20 of them B. bronchiseptica strains were isolated. Eighteen of the strains were toxigenic by at least one test. However, positivity did n ot always coincide amongst assays. This discrepancy raises the possibi lity of either differences in sensitivity between assays or the existe nce of more than one toxin.