Effect of Penicillin on the Maintenance of Rumen Oligotrich Protozoa

Abstract

IT has been shown previously^1,2 that sheep rumen Entodinia spp., principally Entodinium caudatum, could be grown in vitro, dividing every 48 hr. on a medium of salts, dried grass, rice starch, chloramphenicol and fresh or autoclaved rumen fluid, but that it was necessary to add fresh grass and rice starch to the medium every day. This communication describes the successful maintenance of these Protozoa in the presence of penicillin for periods up to 14 days without daily additions.