Hyper-intensive farming of white shrimp Litopenaeus vannamei in a freshwater tank under semi-controlled conditions (Decapoda: Penaeidae)

Abstract

Developing shrimp to a commercial size in a confined freshwater space is important because it saves food and  because predators and diseases are avoided. Our study was conducted to calculate the growth of white shrimp Litopenaeus vannamei by hyper-intensive farming in fresh water from 0,5 to 5‰ and under semi-controlled conditions. We seeded at a density of 563 postlarvae/m3 or m2 during the first cycle and 400 postlarvae/m3 in the second cycle in an outdoor pond of 6m3 or m2 covered with a mesh. Aeration was constant, they were fed Daphnia magna during the first two weeks and then camaronina pellets containing 35% protein, in food baskets, as demanded. The temperature ranged from 22,3 to 31,3°C, pH between 7,5 and 8,7, the oxygen was 4,26±1,43mg/L; the ponds were cleaned of debris every other day, and water was changed according to a program. The food conversion factor (FCA) was 1:1,1. The shrimp were measured weekly to calculate growth using the Bertalanffy model. Survival in the first cycle was 88,1 and 95,8% for the second cycle. Population parameters by maximum likelihood method of the first cycle were k=0,0957, L∞ =146,98 and t0=-0,93; in the second cycle k=0,0172, L∞ =367,82 and t0=-4,60. The results indicate rapid growth during the first ten weeks. Biomass was obtained from 26kg for the first cycle and 16kg for the second cycle.KEY WORDSGrowth, density, survival, biomass, semi-controlled conditions.