Comparison of two selective media for the isolation of Brucella melitensis from naturally infected sheep and goats.

The efficacy of two selective media for the isolation of Brucella melitensis from naturally infected sheep and goats was compared. Two hundred and eighty sheep and 60 goats belonging to B melitensis-infected flocks were slaughtered and samples of milk (when available) and seven tissues were taken from each animal for bacteriological analyses. A modified Thayer-Martin's medium was more sensitive than Farrell's medium; by the combined use of both media 142 infected sheep and 40 infected goats were detected, and 486 of the samples from the sheep and 179 of the samples from the goats were found to be infected.