Ontogenetic changes in digestive enzyme activities of a common water flea

To clarify the ontogenetic changes of digestive enzyme activities in zooplankters, we examined five digestive enzyme activities related to the assimilation of carbohydrates, lipids, amino acids, and phosphorus using a common Daphnia species under different food abundances. In the present analyses, we found that the activities of at least some digestive enzymes changed ontogenetically, suggesting that the nutritional demands differ between mature and immature individuals in Daphnia. We also found that most digestive enzyme activities differed significantly between the neonates from the first and second clutches. The result implies that mature individuals invest nutrients and energy reserves differently to neonates in different clutches depending on their nutritional conditions.

Automated summary

In order to understand the developmental changes of digestive enzyme activities in zooplankters, we investigated five digestive enzyme activities related to nutrient assimilation in a common Daphnia species under varying food abundances. Our analysis revealed that some digestive enzyme activities changed during ontogeny, indicating different nutritional demands between mature and immature individuals. Additionally, we observed significant differences in digestive enzyme activities between neonates from different clutches, suggesting varied nutrient allocation from mature individuals to neonates depending on their nutritional conditions.