Functional Morphology of the Utilization of Starch Grain by Rumen Entodiniid Ciliates In Vitro

Abstract

Degradation of starch grains by entodiniid ciliates from a goat rumen was investigated morphologically in vitro. The ciliates obtained from the culture were stained with iodine and PAS stain for light microscopy, or treated by resin-pulverizing method for scanning electron microscopy. When the ciliates were cultured with various kind of starch grain, favorable maintenance of the ciliates was done when the smaller grains, such as rice strach, were added in the culture. It indicates that the ability of assimilation of starch is closely related to the size of starch grain. The starch grains added were taken very quickly in the ciliate body (within 5 minutes). After that, the grains became smaller gradually, and disappeared about 72 hours after. Following the contraction of starch grains, PAS positive fine grains were noticed in the ectoplasm of ciliate. From the result that these fine grains disappeared in the starvation culture, it seemed that these grains were reserve materials for the rumen entodiniid ciliates.