[Behavior of rumen ciliate populations cultured in sucrose and sucrose-urea media].

The behaviour of rumen ciliates in culture in vitro is studied according to the concentration of substrates and requirements of middle removal. The most favorable concentrations, for a best ciliate's survival is from 0.4 to 0.6 mg/ml of sucrose and 0.05 mg/ml of urea. We observe two periods in the culture: in the first, Entodinium grows essentially, in the second the population of holotrich ciliates increases. If survival is almost the same, the population is most important in culture with sucrose urea than with sucrose.