Ontogenetic change in dietary selection for protein and lipid by gypsy moth larvae

Abstract

Physiological changes during insect ontogeny should be manifest in changes in nutrient requirements and food preference. To investigate ontogenetic changes in food preference and digestive physiology, third-through sixth-instar gypsy moth larvae were provided choices among artificial diets differing in protein and lipid concentrations. Control larvae received two identical cubes of diet that were nutritionally complete, each containing a balanced mixture of protein and lipid. A second group of larvae received two different but complementary cubes, one deficient only in protein, the other deficient only in lipid. During early to late instars, preference shifted away from lipid-deficient, high protein cubes toward proteindeficient, high lipid cubes. This is consistent with the need for late-instar larvae to accrue energy reserves and specific fatty acids required during the pupal and non-feeding adult stages. Male larvae ate a higher proportion from the protein-deficient, high-lipid cube than females, possibly the result of greater energy demands by adult males. Female larvae tended to grow faster on deficient, complementary cubes than larvae provided complete cubes, despite poorer food utilization efficiency. These shifts and sex-specific variations in preference for protein and lipid likely reflect changing nutrient demands and fundamental physiological differences. Food preference Ontogeny Protein Nitrogen Lipid Lymantria dispar

Macronutrient ratios in pollen shape bumble bee ( Bombus impatiens ) foraging strategies and floral preferences

“…Furthermore, our studies demonstrate that B. impatiens does not simply avoid pollen (or diets) with high lipid content: One of their most preferred plant species, T. ohiensis, had relatively high lipid concentrations (Table 1), and they preferentially consumed modified diets with moderate lipid concentrations. Thus, similar to other insects [caterpillars and predators (37,38,44)], B. impatiens appears to regulate the intake of dietary P:L ratios, which may, at least partially, drive feeding behavior in bees.…”

Response of Lymantria dispar (Lepidoptera: Lymantriidae) larvae from differently adapted populations to allelochemical stress: Effects of tannic acid

“…The nutritional requirements of an insect alter throughout development. In older gypsy moth larvae, the change in preference from a high protein to a high lipid diet is related to increased accumulation of energy reserves required for the non-feeding stages (Stockhoff, 1993). This could be reflected through decreased total proteases activity and increased lipase activity recorded in larvae from both populations.…”

Adaptive phenotypic plasticity of gypsy moth digestive enzymes

“…Undeniably, the most evident inducible enzymatic response to dietary stress, which was clearly connected with higher larval relative fitness on the tannin-supplemented diet, was significantly higher lipase activity. As shown in gypsy moth larvae, lipids are very important for energy storage during advanced larval instars [66]. Since dietary lipids are richer sources of energy than proteins, higher lipase activity may provide efficient usage of dietary lipids and accordingly, acquisition of sufficient energy resources for induction of defense mechanisms in stressful environments.…”