MacConkey and A-1 broths were compared for the MPN enumeration of fecal coliforms in the Sydney Rock Oyster (Crassostrea commercialis), using an incubation regime of 2 h at 37 ± 1 C followed by up to 46 h at 44.5 ± 0.5 C. A higher recovery was obtained with MacConkey broth, with ratios of the geometric mean MPN values of 111 samples tested in A-1 and MacConkey broth of 0.5460 and 0.5654 after 24 h and 48 h incubation, respectively. Incubation for 48 h produced significantly higher counts than 24-h incubation for both broths.

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