Kinetics of large ciliate protozoa in the rumen of cattle given sugar cane diets (original) (raw)

1. Experiments were undertaken to examine the kinetics of large ciliate protozoa in the rumen of cattle on sugar-cane diets.2. Three Zebu bulls were fed once daily on a diet of sugar cane and wheat bran. The diurnal patterns of volatile fatty acids and ammonia concentrations, and the numbers of protozoa in rumen fluid were determined. The numbers of protozoa reached values of 5 × 104/ml for holotrichs (large ciliates) mainly Isoiricha and Dasytricha spp and 4 × 105 for smaller protozoa, mainiy Entodinia (small ciliates)3. A method was developed which allowed large ciliate protozoa in rumen fluid to be separated from plant material and bacteria and concentrated in a relatively uncontaminated form. Analysis of these protozoa indicated that 1.8 × 105 large ciliates contained 1 mg nitrogen and approximately 32 mg dry matter4. A labelled preparation consisting mainly of large ciliates (principally Isotricha spp.) was obtained by incubating isolated protozoa in rumen fluid (free of plant ...