Female Growth and Offspring Quality over Successive Spawnings in a Caridean Shrimp Neocaridina davidi (Decapoda, Atyidae) with Direct Development

Abstract

This study analyzed the quality of recently spawned eggs and of juveniles over five and six consecutive spawns, respectively, in a caridean shrimp Neocaridina davidi with direct development. The potential energetic antagonism between reproduction and somatic growth was also evaluated. The number of eggs per spawn per female was highest in the first spawn, while the number of recently hatched juveniles per spawn per female declined in the sixth spawn. Lower lipid concentration and energy content were detected in eggs of the fourth and fifth spawns, which may indicate for the first time a decrease in maternal provisioning as a result of multiple spawning in a decapod with direct development. This result had no effect on the size of eggs or of recently hatched juveniles, nor on the growth performance of juveniles during a 30-day period following hatching. Lipids were the most abundant biochemical component of eggs, followed by proteins and glycogen; the relative proportion of each component was probably related to embryonic development type. Egg volume was unsuitable as an indicator of nutrient content, as no correlation was found between these variables. The physiological costs of reproduction were evident from the lower energy content of females that reproduced versus females that remained virgin. The lower body weight of the reproductive females at the end of the experiment showed that allocation of resources to reproduction occurred at the expense of somatic growth. To our knowledge, this is the first empirical demonstration of a decapod with direct development.