Respiratory energy losses related to cell weight and temperature in ciliated protozoa.

Respiratory energy losses in five species of ciliated protozoa, Tetrahymena pyriformis Ehrenberg, Vorticella microstoma Ehrenberg, Paramecium aurelia Ehrenberg, Spirostomum teres Claparède and Lachmann and Frontonia leucas Ehrenberg, were investigated at 8.5° C, 15° C and 20° C using Cartesian diver microrespirometry. Q 10 values of 1.15-2.24 were found for four of the species between 8.5-15° C, while in S. teres a Q 10 of 12.98 occurred between these temperatures. Between 15-20° C T. pyriformis and P. aurelia had Q 10 values of 3.73 and 1.56, respectively. Linear double log regressions of oxygen consumption vs. dry weight were derived at each temperature and regression coefficients (b) of 0.2723 (8.5° C), 0.4364 (15° C) and 0.4171 (20° C) were obtained. The results are explained and discussed in relation to previous work on the energetics of ciliated protozoa.