Mating status affects females feeding behavior but does not the encapsulation response in the field cricket, Gryllus (Gryllus) assimilis (Fabricius, 1775)

Abstract

Mating can trigger different effects on the physiology and behavior of animals, especially in females. These effects can be either beneficial, such as boosting the immune response, or harmful, such as decreasing survival, for example. Cricket females are among the most used models for understanding these life history trade-offs. We recently demonstrated that mated females have a slight cost of reproduction in survival that could be explained if they differed in resource consumption compared to unmated, being able to avoid putative damages of reproduction on self-maintenance. To test whether mating status modulates feeding behavior and self-maintenance (i.e., immunity), we performed two experimental blocks: In the first, we measure the food intake of both virgin and mated females of Gryllus (Gryllus) assimilis (Fabricius, 1775). In the second, we compared the ability to mount an acute immune response (encapsulation) against a nylon filament implant, a widely used method to challenge the insect immune system. Results showed that mated females did not increase food consumption compared to pre-mating period, however, the virgin group (control) drastically decreased the amount of food ingested. Furthermore, no difference in immune response was found between mating status. As mated females ingested more food than those virgins of the same age, we suggest the feeding behavior (i.e., resource acquisition) as one of the used behavioral strategies to maintain immune ability, high oviposition rates, and survival of mated females of G. (G.) assimilis when fed ad libitum.