Influência da densidade de estocagem e frequência de alimentação no crescimento do camarão Litopenaeus vannamei na fase de berçario em sistema de bioflocos

Abstract

This dissertation is divided into two chapters corresponding to two papers, the first evaluated the growth performance of the marine shrimp Litopenaeus vannamei grown in different stocking densities, while the second evaluated the influence of different feeding frequencies in the growth of L. vannamei both in nursery stage bioflocs system. The first experiment consisted of four treatments with three repetitions, corresponding to densities of 1500, 3000, 4500 and 6000 shrimps/m². Shrimps with initial average weight of 0,004g were stocked at random, as the treatments on 12 circular plastic tanks with bottom area of 0.5 m2 and useful volume of 300L for a period of 35 days. Water quality variables remained within acceptable limits during the experiment. The results for the growth performance showed significant differences between treatments. The final weight values were higher in farmed shrimp in densities of 1500, 3000 and 4500 m², while survival was significantly reduced at densities of 4500 and 6000 shrimp/m². The second experiment consisted of four treatments and three replications food corresponding to frequencies of 1, 2, 3 and 4 times daily. Shrimps with initial average weight of 0,004g were stocked at random, as the treatments on 12 fiber boxes, with bottom area of 1.0 m2 and useful volume of 1000L over a period of 35 days. These tanks were connected to a recirculating water system supplied by a tank 10000L matrix, used for performing fertilization, aimed at forming bioflocs. Water quality variables remained within acceptable limits during the experiment, except that the temperature had from the fourth week values uninspired, probably influencing the growth. The results for the average final weight showed significant differences between treatments, indicating that the daily power equation reflects the shrimp growth. Based on the results obtained in the first experiment, density 3000 shrimps m2 was considered most appropriate in terms of overall growth performance, whereas the second experiment the feed frequency of three times a day was considered the most suitable for growth of L. vannamei in the nursery phase in bioflocs system in Northeastern Brazil.