Survival of white shrimp larvae grown in different containers and fed
natural or artificial diets

A. O.  Meyer-Willerer

Survival of white shrimp larvae grown in different containers and fed natural or artificial diets

Autores

A. O. Meyer-Willerer

Editor

Universidad de Colima

Descripción

Artificial and natural feeds for shrimp larvae cultures (Litopenaeus vannamei) were tested in a series of containers. These were eight flasks with 15L, eight aquaria with 50L and as control group six large fiberglass tanks with 1500L, all with fresh marine filtered water. Initial density in all containers was 70 nauplii/L. Those in flasks and aquaria received either natural feeds, or artificial diets. The control group were fed natural diets and were cultured in large tanks that are normally used in postlarvae hatchery laboratories. The main soluble product excreted by shrimp larvae is the ammonium ion that is toxic, when present in high concentrations. It was determined daily with the indophenol colorimetric method. Results show differences in ammonia concentration and larval survival between the different diets and also between containers. In small water volumes compared to larger ones, the natural products presented higher total ammonia ion concentration present (from 500 to 750µg/L) due to this ion added to the algae as fertilizer, needing daily water exchanges after the ninth day of culture to keep this ion under lethal concentration for shrimp larvae. Poor postlarvae survival was achieved (less than 15%) with the artificial fed larvae due to the presence of protozoa feeding on precipitated diet in the bottoms of the flasks or aquaria. Those larvae in aquaria presented also sublethal ammonia ion concentrations at the ninth day, but survival rate with natural feeds was almost four times higher, than with artificial diets. Control tanks with natural feeds presented survival rates (70 ± 5%) similar those reported in other larvae laboratories.