The livers and tongues were swabbed just after removal of the pluck and the carcasses immediately before or after blast chilling.
Individuals were swabbed on up to eight occasions over the study period, which lasted 29 weeks.
The total area swabbed was around 0.4 m2.
The anterior segment of the eye was removed, as much as possible of the vitreous body gently swabbed away, and the eyecup ever ted.
Tongues were swabbed with one diaper, from the dorsal part of the larynx, over the pharynx until the tip of the tongue.
Longitudinal carriage studies, in which individuals are swabbed repeatedly over several weeks or months, can be particularly informative.
The average number of suspected colonies counted on the directly swabbed plate and the plate with the 3-ml saline suspension was recorded.
The data comprised the results of swabs from 283 recruits swabbed repeatedly over a year on up to 14 occasions.
