Larval fish

Aquaculturists may elect to purchase animals for stocking or maintain their own broodstock and hatchery. The decision may rest on such factors as the availabihty and cost of fry fish, post-larval fish, oyster spat, or other eady life history stages in the location selected for the aquaculture venture. 

Barron, M.G. and I.R. Adelman. 1984. Nucleic acid, protein content, and growth of larval fish sublethally exposed to various toxicants. Canad. Jour. Fish. Aquat. Sci. 41 141-150. 

Larval fish should have food provided beginning at 5-6 days post-fertilization (dpf). Food may include live paramecia and/ or dry larval diet. Feed twice daily. 

Several studies have also focused on the phospholipid requirements in larval fish and crustaceans. In particular, the effects of diets supplemented with different mixtures of phospholipids... 

Most larval fish (e.g., sea bass, salmon, trout, turbot, seabream, flounder, carp, and goldfish) have a requirement for dietary phospholipids. The phospholipid requirement generally decreases with age or developmental stage. The requirements also differ between species (321). 

How might species differences in egg lipid content and the timing of yolk consumption affect POP deposition into developing embryos or larval fish Before addressing this issue, a brief overview of egg biochemistry and yolk dynamics in fish embryos and larvae is warranted. 

Laboratory experiments have demonstrated that larval fish do feed better in... 

Many species of larval fish have retinal cones that perceive UV-A (350-370 nm) and these are thought to help larvae locate and capture their prey [63,64]. However, some prey species also have UV-A photoreceptors. Responses to UV-A wavelengths in these organisms may therefore also be a means of predator avoidance in the surface waters. In this case, predation may be the ultimate cause of DVM but UV-A light would be the proximate cue. Further investigation is needed to test these types of hypotheses. 

At about the same time, others groups began investigating the toxicity of Pfiesteria using alternative approaches. One group examined organic extracts of lyophilized Pfiesteria cells, all of which failed to kill larval fish [18], Since most known algal toxins have a polyketide structure, other researchers used molecular primers to demonstrate that at least P. shumwayae most likely lacked the polyketide synthases needed to synthesize this class of toxins [18]. 

It seems to be impossible energetically for larval fish to be operating at 10% efficiency of retention [(50/500) X 100]. Simultaneous measurements of protein growth, protein synthesis and oxygen consumption of larval fish are needed to resolve these problems. 

It has been suggested that the postulated high protein synthesis rates of larval fish may be due to the relatively high proportion of the body occupied by the intestine which will have a high rate of synthesis relative to the white muscle (Dabrowski 1986 Weatherly and Gill 1987). Thus as body size increases not only may fractional rates of protein synthesis of individual tissues decline but also the relative proportions of the body may change with a relative increase in slowly synthesising white muscle. 

Brown CR (1988) The physiological basis of specific dynamic action The relationship between protein synthesis and oxygen consumption in Ictaluruspunctatus. PhD. Thesis, Univ Texas at Austin, USA Brown CR, Cameron JN (1986) The relationship between specific dynamic action (SDA) and protein synthesis in the channel catfish. Am Zool 26(4) 124A Buckley LJ (1984) RNA-DNA ratio an index of larval fish growth in the sea. Mar Biol 80 291-298... 

GUNVOR 0, reitan k I, EVJEMO J o, ST0TTRUP J and OLSEN Y (2011) Live feeds, in Holt J G, (ed.). Larval Fish Nutrition. Chichester Wiley-Blackwell, 307-334. 

RHODES A (2003) Methods for high density batch culture of Nitokra lacustris, a marine harpacticoid copepod, in Browman HI and Skiftesvik A B (eds). The Big Fish Bang, Proceedings of the 26" annual larval fish conference. Bergen Institute of Marine Research, 449-465. 

HOLT J (2011) Larval Fish Nutrition. Chichester Wiley-BlackweU. 

KJORSViK E, GALLOWAY T, ESTEVEZ A, SAELE o and MOREN M (2011) Effect of larval nutrition on development, in Holt J (ed.). Larval Fish iVi[Pg.221]

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