Ref ID : 1725
Edward K. Mercer and Eldon J. Cairns; Food consumption of the free-living aquatic nematode Pelodera chitwoodi. J.Nematology 5(3):201-207, 1973
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A Cartesian diver respirometer was used to measure O2 uptake and respiratory quotients at 25 degrees C. Respiratory quotients were about 0.70 in starved nematodes, and 0.80 in third-stage and adult nematodes that had fed on bacteria. The energy output as measured by O2 uptake was inversely related to the concentration of bacteria in the medium, indicating reduction in feeding effort. Feeding bacteria to third-stage nematodes in divers quickly resulted in peak respiration rates averaging 6.4 nlO2/µg wet weight nematode per hour (QO2) or six times the endogenous rate. In about 4 hr, the rates fell and then stabilized at a QO2 of 2.5. Adult males fed bacteria in divers had a peak QO2 of 2.8 or twice the starved rate. Adult females fed bacteria had a peak QO2 of 3.7. Starving adult males and third-stage larvae were estimated to lose 2.4% and 1.4%, respectively, of their body weight per day in the form of fat based on the caloric equivalent of oxygen used and a respiratory quotient of 0.70. The caloric content of the bacteria fed to nematodes in divers was determined. It was then calculated that both third-stage larvae and adult males ingested bacteria equivalent to 4.4x10E5 cal/µg wet weight nematode tissue per hour when feeding. Of the bacterial calories ingested, the larvae used 27% and adults 21% for respiration. It was estimated that males ingested 3.1x10E6 bacteria and females 10x10E6 bacteria during an 8-day life span.