Previous studies indicated that female Heliothis virescens and Estigmene acrea caterpillars use both feeding and postingestive processing as mechanisms to meet nutrient demands. We present utilization and nutrient budget data on the postingestive partitioning of nutrients into pre- and postabsorptive components. Both species utilized @entity1735 efficiently except at very high ingestion rates. Of the @entity1735 utilized, more was unaccounted for as intake increased, and we assume the material unaccounted for served as a respiratory substrate. In contrast, the pattern of @entity1568 utilization differed between the species. Larval H. virescens efficiently retained @entity1568 except at very high ingestion rates, whereas E. acrea progressively increased @entity1568 egestion in response to increased @entity1568 ingestion. Overall, females of both species utilized @entity1568 more efficiently than did males at most ingestion levels, thus contributing to the greater protein-derived growth we previously reported. In addition, for H. virescens, protein and @entity1522 accounted for a small proportion of fecal @entity1568 so that most of the fecal @entity1568 was of a postabsorptive nature. In contrast, @entity1568 excreted by E. acrea could be partitioned into both pre- and postabsorptive components. The manner of postingestive processing by these two species reflects differences in their larval diet.

Sexual differences in postingestive processing of dietary protein and XXXX in caterpillars of two species.

@entity1522 :: ('CHEBI:33709', 'Chemical') :: ['amino acids'] @entity1568 :: ('MESH:D009584', 'Chemical') :: ['nitrogen'] @entity1735 :: ('CHEBI:16646', 'Chemical') :: ['carbohydrate']
@entity1735 :: (CHEBI:16646,Chemical) :: ['carbohydrate']
