he experiment was performed in order to investigate the applicability of the rapid detection of salmonellae in various animal-origin foods by means of the direct fluorescent antibody technique.
Egg, sausage and chicken were inoculated with various concentrations of Sal.paratuphi A, Sal. paratyhi B and Sal. thompson, and the fluorescent antibody technique was applied and compared with the conventional cultura method for the sensitivity of detection of the organisms. Two methods were employed in the fluorescent antibody technique; the direct smear method in which the smear being made directly from the specimens, and the enrichment smear method in which the smear being made from the enrichment broth.
The effect of various enrichment time (1,5,8,11 and 13 hours) in tetrathionate broth on the detection of salmonellae in the fluoresent antibody technique was also studied.
The results obtained were summarized as followings;
1. Of the three methods, the enrichment smear method of fluorescedt antibody technique was highly effective as cultural method for the detection of salmonella organisms.
2. Direct smear method of fluorescent antibody technique was effective as two other methods 5×10⁴ organisms presented in 50 g(㎖) of specimens. This method may not be applicab1e when the specimens contained 5×10² or less organisins.
3. Of the three specimens, the recovery rate of Salmonella organisms from egg was slightly higher than that of sausage and chicken.
4. In fluorescent antibody technique and cultural method, the specimens inoculated with Sal. thompson were found to be higher detection rate than the specimens inoculated with Sal. paratyphi A,
5. The optimum enrichment time of Salmonella organisms in tetrathionate broth on the detection by fluorscent antibody technique was found to he 11 hours or longer when the specimens of egg, sausage and chicken were inoculated with approximately 500 organisms. The longer enrichment time was the higher detection rate up to 11 hours tested.
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