Avaliação de diferentes fontes de carbono no desenvolvimento de juvenis de Tambatinga (Colossoma Macropomum X Piaractus Brachypomus) cultivado em sistema bioflocos

Abstract

In this study, the use of three different sources of organic carbon in the development of juveniles of the tambatinga hybrid (Colossoma macropomum X Piaractus brachypomus) cultivated with biofloc technology. For this, three replicates were used, totaling 9 experimental units, each being fertilized by a source (refined sugar, tapioca gum and wheat flour), where these replicates were ordered randomly for 28 days. Twenty individuals were stored in each experimental unit. The fertilization of the experimental units was based on the amount of ammonia present in the system. The hydrochemical parameters monitored were: total ammonia, toxic ammonia, nitrite, water temperature, dissolved oxygen, carbon dioxide, total dissolved solids, pH and sedimentation of microbial flakes. The identification of the organisms present in the microbial flakes was at the level of large groups like kingdom and phylum. Biometrics were done biweekly every two weeks, with the aim of having: weight gain, final biomass, survival rate, apparent feed conversion, specific growth rate and productivity. The data were statistically analyzed in program R. Of the hydrochemical parameters the temperature of the water, dissolved oxygen, pH and carbon dioxide were within the recommended for the development of the species for all the treatments, however, the toxic ammonia was elevated during the whole period of culture, leading to the mortality of many individuals, mainly in the treatment with wheat flour, due to that this treatment was the one that presented lower survival rate. The individuals with the tapioca gum were the ones that presented the best feed conversion and also the best productivity per cubic meter, it was also the treatment that presented more water consumption and less diversity of organisms in the flakes, but the refined sugar was the which had less water consumption at the same time as it had a good productivity, was also the treatment where the individuals presented the best relation weight-length and greater diversity of organisms. The treatments with tapioca gum presented better efficiency and practicality of handling, the refined sugar had a good efficiency, however one has to be more careful when handling and the wheat flour was the less efficient and more complicated to handle. More in-depth studies are needed to have more precise conclusions about the subject.