Nutrition of Juvenile and Adult Fish

Abstract

For marine fish farming to be feasible, foods that produce adequate growth and survival at an acceptable cost are necessary. It is useful to group fish into five feeding categories: pelagic carnivores, demersal carnivores, demersal omnivores, demersal herbivores, and planktivores. With few exceptions (e.g., milkfish, ayu, tilapia, striped mullet), most mariculture candidates fall into the first three groups. Requirements vary broadly among categories and on a finer scale among species within categories. Needs also are affected to a degree by factors such as age, size, growth rate, developmental stage, density, food quality, water quality, temperature, salinity, pH, photoperiod, stress, and health. Availability of feed ingredients varies among regions, and will influence the composition of least-cost formulas. High quality trash fish sometimes is used for grow-out of carnivorous and omnivorous marine fish, but unless it is very fresh, such a diet can carry pathogens and toxins, or be nutritionally deficient (Taniguchi, 1983a, 19836; Nakagawa et al., 1984). In Japan and Europe, some commercial feeds are available, but in other Far Eastern countries, the Middle East, Australia, and the Western Hemisphere, development of feeds for non-salmonid marine fish is relatively recent. Some of the earlier literature on feeding marine fish was reviewed by New (1986). This chapter reviews research on nutrition of representative cultured marine fish and makes some suggestions on fulfilling their requirements.