Age‐dependent changes in reproductive allocation in a facultative ectoparasite, the blowfly Lucilia sericata (Meigen) (Calliphoridae)

Abstract

Organisms trade‐off limited resources between life‐history traits to maximize fitness. In particular, costs associated with reproduction are balanced against somatic maintenance and this can result in age‐dependent changes in the optimal allocation of resource to reproduction. Changes in the allocation of resources to reproduction with age were considered in the facultatively parasitic blowfly Lucilia sericata (Diptera: Calliphoridae), using biochemical analysis of lipids in the body and ovary, and lipid and protein in individual eggs. Resource allocation to reproduction, measured as lipid content in the ovary, declined over time. This decline was associated with the production of fewer and smaller eggs per batch. The lipid content of the residual body did not change. A decrease in lipid and increase in protein contents of individual eggs over time, although statistically significant, were relatively slight, suggesting that age‐related changes in nutritional allocation to individual eggs were more subtle than changes in egg batch number or size. This study highlights the insights to be gained from considering both biochemical measures of nutritional allocation, and observable measures of reproductive effort, when evaluating how females balance allocation across competing life‐history traits. Future work should explore how allocation patterns might vary under conditions of resource constraint and whether age‐dependent allocation in laboratory flies is representative of that found in wild populations.

Female delayed mating has a limited impact on the reproductive output of Cerambyx welensii, a synovigenic longhorn beetle

“…Through oosorption, females are able to reallocate reproductive resources (mostly yolk material from mature oocytes) to fuel somatic maintenance, which would otherwise be wasted as unfertilised eggs. Thus, in response to a mating delay, females may allocate less resources to egg production and more to somatic maintenance, expecting future mating chances and reproduction (Alqurashi et al, 2023; Fadamiro & Baker, 1999; Proshold et al, 1982; Zheng et al, 2020). Our results, however, suggest that oosorption appears to be inappreciable or lacking in Cw since female longevity was similar regardless of mating delay and also because post‐mating fecundity was roughly equivalent in the female groups mated until 20 days of age (MD0, MD10 and MD20).…”

Effects of larval diets on some biological parameters and morphometric and biochemical analysis of ovaries of Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae)

“…Adult Lucilia are anautogenous and require several protein meals to complete egg development, but even small protein meals can initiate yolk deposition in some eggs (Wall et al 2002, Alqurashi et al 2023). We observed that the ovaries of two-day-old flies reared (as larvae) on chicken meat had higher amounts of protein than those of flies reared on beef liver, and that this reflected the higher relative protein composition in the chicken meat itself.…”

“…Egg maturation in the related species L. sericata requires about a week if protein is provided (Wall et al 2002). Further research would be needed to determine whether the higher protein levels in eggs of young flies would be sufficient to speed up the timeline for egg maturation after the flies were given additional protein meals (Alqurashi et al 2023).…”