After the syringes were held for approximately 5 hours in a lighted incubator at 26oC, each syringe was removed, and the change in O2 concentration was recorded and used to determine metabolic rate. Each cockroach was weighed to the nearest 0.01 mg immediately after removal from the incubator. Separate trials were conducted on 4 different days, yielding data on 20 males and 20 females in both the Orlando Normal and Village Green strains. Mean metabolic rates and weights of both strains are listed in Table 1. Resistant and susceptible strains had similar metabolic rates, and thus resistance may not have an energetic cost.
Several explanations exist for the similar metabolic rates of the two strains.
This research was in part funded by the Clorox Company. Summary Metabolic rates, based on oxygen consumption, were determined for two strains of German cockroaches, one resistant and one non-resistant. Both strains had similar metabolic rates suggesting that resistance may not have an energic cost. References Cited Anderson, J. F., C. A. Lanciani, and J. T Giesel. Diel cycles and measurement of metabolic rate in Drosophila.