Coleman G S, Laurie J I, Bailey J E
J Gen Microbiol. 1977 Aug;101(2):253-8. doi: 10.1099/00221287-101-2-253.
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.
瘤胃纤毛虫原虫——袋状内毛虫已在含有细菌和尾状内毛虫的体外环境中培养了一年多，种群密度为100至200个/毫升。培养基含有磷酸钾、新鲜制备的瘤胃液、半胱氨酸、全麦粉（或大米淀粉）、干草以及无棘尾状内毛虫培养物。袋状内毛虫对这种原虫有绝对需求，在没有它的情况下48小时内就会死亡。从2%的接种量开始生长期间，袋状内毛虫的平均世代时间为6小时。袋状内毛虫每小时吞噬1.5至2.5个尾状内毛虫个体，当尾状内毛虫数量过多时，它在17年来首次长出尾刺；这些有刺形态的个体比无刺个体更不容易被吞噬。
