title: The cultivation of the rumen ciliate Entodinium bursa in the presence of Entodinium caudatum.
abstract: The rumen ciliate protozoon Entodinium bursa has been grown in vitro in the presence of bacteria and Entodinium caudatum for over a year at population densities of 100 to 200 ml-1. The medium contained potassium phosphate, prepared fresh rumen fluid, cysteine, wholemeal flour (or rice starch), dried grass and a culture of the spineless form of Entodinium caudatum. Entodinium bursa has an obligate requirement for this protozoon and died within 48 h in its absence. During growth from a 2% inoculum, the mean generation time of E. bursa was 6 h. Entodinium bursa engulfed 1-5 to 2-5 E. caudatum organisms h-1, and when E. caudatum was in excess it developed caudal spines for the first time in 17 years; these spined forms were engulfed much less readily than the spineless organisms.
mesh_terms: D000818:Animals; D016798:Ciliophora / Q000166:cytology / Q000254:growth & development*; D003470:Culture Media; D010587:Phagocytosis; D012417:Rumen / Q000382:microbiology*; D012756:Sheep
chemical_list: D003470:Culture Media