Influence of Maternal Size, Offspring Feeding and Their Interaction on the Hatchery Outcomes of an Indian Major Carp, Rohu (Labeo rohita)

Abstract

Broodstocks' size and larval feeding are very crucial in quantitative and qualitative production of gametes and offspring in any fish breeding system. Therefore, this study was carried out to investigate the influence of maternal size, offspring feeding strategy and their interaction on spawning performance and offspring fitness using a highly commercially important aquaculture species, an Indian major carp (Labeo rohita). The entire study was comprised of two experiments, such as 1) maternal size effect and 2) maternal size, offspring feeding and their interactive effects. During the study, females were divided into two size groups ('large' and 'small'), while offspring were randomly assigned into two feeding strategies ('everyday' and 'every other day'). The results revealed that larger mothers produced significantly higher amount of eggs with enhanced hatching and reduced deformation rate, and larger sized offspring than the smaller mothers. The offspring feeding strategy disclosed that everyday fed offspring had higher survival and better size than those fed every other day. The study did not find any significant effect of maternal size on egg number and size, and offspring survival, while interaction between maternal size and offspring feeding showed no significant effect on any offspring trait which confirmed that very strong effects of maternal condition and offspring feed deprivation were not compromised with any change. The overall findings of this study suggest that maternal size and regular offspring feeding must be considered to produce high quantity and good quality of gametes and offspring for sustainable production of this valuable species.