Role of recent feeding protocols, rearing water systems and microbial trends in improving marine larviculture: insights into water quality and larval performance

Document Type : Review

Authors

• Heba S. El-Sayed
• Sara F. Ghanem
• khouloud M. Barakat

National Institute of Oceanography and Fisheries, NIOF, Egypt

10.22034/iar.2024.2008550.1645

Abstract

Larvae nutrition is considered to be the ‘bottle neck’ for marine finfish culture. Nowadays, marine larviculture can be significantly enhanced by producing new protocols of live feed using modern microbial trends. Primary goals of successful farmed larvae mainly rely on excellent survival and growth, since marine fish larvae record unpredicted high mortality rate and poor performance on designed diets during weaning stage. Adding live or inactive food to the rearing systems is also a widespread technique that has a significant impact on larval survival and performance. The bulk of mass-cultured marine fish larvae still need live feeding species, particularly at the beginning of larval nutrition such as: Artemia (brine shrimp), rotifers Brachionus spp., and microalgae. Bacteria are also added with live food and microalgae in the larval tanks for the rearing water system. Therefore, this review shed light on the developments of water rearing systems and improvements in marine fish larvae diets by discussing different types of live feeds and formulation of weaning microdiets. Since larval development is the most crucial stage of marine aquaculture production during which the greatest death rates can exceed 70%. Hence, the ontogenic development and digestive physiology of fish model larvae are also highlighted. Beneficial effects of prebiotics and probiotics on improving feed utilization and water quality, promoting larval growth and enhancing disease resistance were also discussed. Moreover, additional case studies about live food enrichment and reared fish larvae were presented to elucidate their effective role in improving water quality and larval growth performance. Despite recent substantial advancements in marine larviculture, many questions about fish larvae nutrition remain unanswered and numerous research avenues remain unexplored. Suggestions, recommendations and future considerations were mentioned to improve diets during larval rearing and pinpoint the research gaps that need to be addressed in manual hatchery operations.

Keywords

• Marine larvae
• Ontogenic development
• Digestive system
• Diets
• Water systems
• Microbial trends

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