Experimental studies on the effect of food in early larvae of the cleaner shrimp Lysmata amboinensis (De Mann, 1888) (Decapoda Caridea: Hippolytidae)

Identifying appropriate larval husbandry is a key to improve larval quality and shorten duration of larval stages, and culture costs of ornamental cleaner shrimps Lysmata amboinensis. Several feeding and zootechnical experiments were conducted under laboratory conditions to test the effect of food during the first day posthatch, the effect of feeding with microalgae on larval digestion after 24 h posthatch, the effect of enriched rotifers upon survival and the combined effect of stocking density and food concentration on growth and survival of young larvae. For the first time, oxygen consumption values, trypsin-like activity and metabolite content (protein and triacylglycerols) were determined for L. amboinensis early stage larvae. When starved during the first day of life, L. amboinensis larvae had the same oxygen consumption as fed larvae, indicating that food ingestion is not crucial during that period. Nevertheless, energy reserves such as TAG were significantly lower in 24 h starved larvae when compared with fed larvae indicating facultative primary lecitotrophy. Trypsin-like activity of digestive enzymes (U mg prot^{- 1}) was low when compared with other decapod larvae. Larvae fed with Tetraselmis chuii showed a significant increase in enzyme activity after 24 h. Present results showed that enriched rotifers result in higher larval survival during the first days of life when compared with larvae fed with non-enriched rotifers and that survival is not dependent on the relation between larval density and food concentration. In addition, stocking densities of 10 larvae ml^{- 1} showed higher survival compared to that obtained at the stocking density of 20 larvae ml^{- 1}.