FISH LARVAL NUTRITION AND FEED FORMULATION - KNOWLEDGE GAPS AND BOTTLENECKS FOR ADVANCES IN LARVAL REARING (A LARVANET REVIEW)

摘要

The requirements of most of the nutrients in fish larvae are unknown, due to difficulties in making the graded, stable and easily bio-available diets needed in dose response experiments. Instead, researchers have tried to find indirect methods to measure the nutrient requirements. One method is to analyze the nutrient profile of the main natural diet, copepods, assuming that these organisms cover the requirements. Another is to extrapolate the requirements in fish to the larval stage. Other methods based on nutrient composition and utilization of the yolk and the uptake and metabolism of radiolabeled nutrients have also been applied. An important aspect is the definition of the requirement, e.g. the requirement for pigmentation and immune function may be different from that for optimal growth and survival. Furthermore, requirements may differ between species and with environmental conditions.