PRELIMINARY PREY DIGESTION IN A PREDACIOUS ESTUARINE CILIATE AND THE USE OF DIGESTION DATA TO ESTIMATE INGESTION

Digestion of ciliate prey (Pleuronema sp. and Metanophrys sp.) in Euplotes woodruffi was examined in laboratory experiments. Similar exponential declines in recognizable food vacuole contents were found in feeding and non-feeding cells. Ingestion rates, based on digestion rates and food vacuole contents, yielded estimates of 0.4-1.6 Pleuronema and 3.7-4.2 Metanophrys consumed per E. woodruffi h-1 at 20-degrees-C, in agreement with rates obtained by other methods. Cells starved for 24 h showed faster digestion rates; temperature variation over a range of 15-degrees-25-degrees-C gave a Q10 of approximately 1.5.