Thermal Effects on the Body mass, Transpiration rate, Feeding and Food Conversion of the Pillbug Armadillo officinalis (Isopoda, Oniscidea) Fed on the Dry Leaf of Punica Granatum

Abstract

Observations were made on the body mass; transpiration rate; assimilation efficiency; gross and net production efficiencies; feeding, assimilation, conversion and metabolic rates of the pillbug Armadillo officinalis Dumeril acclimatized at 14º and 21 °C for 15 days and fed on the dry leaf of Punica granatum (Pomegranate). A brief description is given on the chemical composition of P. granatum leaf. The difference in body mass increments of A. officinalis between the acclimatized temperatures was not significant (t = 1.09; p>0.05). However, significant differences were discernible on the transpiration rate (t = 9.53; p<0.01), moisture (t = 9.01; p<0.01), assimilation efficiency (t = 5.16; p<0.01), feeding (t = 3.76; p<0.05) and conversion (t = 2.58; p<0.05) rates between the woodlice acclimatized at 14º and 21 °C. Better feeding of P. granatum leaf by these animals was observed at 21° C, but better assimilation efficiency at 14 °C. Only 3.21% assimilated food at 14° C and 6.30% at 21 °C were converted into the production of new tissues. The food consumption of A. officinalis at 14º and 21° C was 2.05% and 3.79% body mass/day respectively. The effect of temperature on the activity of A. officinalis in the field is discussed.