Madagascar Hissing Cockroach hemolymph PO2, PCO2, and gas exchange parameters

Methods

These data were collected and analyzed according to the materials and methods in the associated JEB article. Briefly, Madagascar hissing cockroaches (Gromphadorhina portentosa) were secured in a respirometry chamber with PCO2 and PO2 optodes implanted in their hemocoel. A reflection sensor beneath their abdomen recorded abdominal pumping movements.

Cockroaches were exposed to normoxic normocapnia, hypoxic normocapnia, and normoxic hypercapnia. Roaches were exposed to these gas mixtures while intact and breathing continuously, and then decapitated which induced discontinuous gas exchange cycles (DGCs), before being exposed to the same gas mixtures as before. During these exposures, hemolymph PO2, PCO2, VCO2, and abdominal movements were recorded continuously.

The summary data extracted form these data traces are presented here.

Usage notes

Each treatment assumed 6 cockroaches were used. Empty cells indicate that either equipment failure resulted in a parameter (e.g. hemolymph PCO2) not being recorded from that individual insect, or the insect did not display the breathing pattern required to record a certain parameter (e.g., the cockroach began breathing discontinuously, preventing the recording of continuous gas exchange parameters).