Jakeline Marcela Azambuja de Freitas

Desempenho de juvenis de tilápia-do-nilo alimentados com rações contendo complexo enzimático

The aim of this study was to evaluate the inclusion of an enzimatic complex in diets for Nile tilapia (Oreochromis niloticus) on performance, carcass chemical composition as well as water quality. The experiment was performed in 62 days. It was used two hundred reverted fingerlings (14.57 ± 1.24 g) distributed in a complete randomized design in 20 500 L-tanks with four treatments and five replicates, considering a box with 10 fish as a experimental unit. The fish were fed diets containing 0; 0.033; 0.066 and 0.099% of enzimatic complex. The diets were processed in peletized way and supplied four times a day (8:00 a.m., 11:00 a.m., 2:00 p.m. and 5:00 p.m.) The pH average values, electric conductivity, dissolved oxygen, temperature, total phosphorus, ammonia and water nitrate of the cultivation were not influenced by the inclusion of the enzimatic complexin the diet. The inclusion of enzymatic complex in the diet did not affect weight gain, survival, and specific growing rate; however, it affected diet consumption and food conversion, whose values were greater for fish fed 0.066% of enzimatic complex diet. No differences were observed on dry matter, humidity, crude protein, mineral matter, calcium and phosphorus in the fish carcass, nevertheless, the ether extract decreased linearly as the level of enzymatic complex increased. The utilization of enzimatic complex (amylase, protease, cellulase, lipase, pectinase, xylanase, β-glucanase and phytase) at the level of 0.066% for juvenile Nile tilapia (Oreochromis niloticus) worsens food conversion but does not influence performance and body composition of the fish.

Proteína e energia em rações para alevinos de piavuçu

The aim of this study was to evaluate the requirement of crude protein (CP) and digestible energy (DE) in piavucu fingerlings (Leporinus macrocephalus), for a period of 45 days. It was used 150 fingerlings with average weight of 0.40 ± 0.08g, distributed in 30 aquariums (30L) in a completely randomized design in a 3x 2 two-factorial scheme composed of three levels of crude protein (25, 30 and 35% of crude protein) and two levels of digestible energy (3,250 and 3,500 kcal of DE/kg), totaling six diets and five replicates. The rations were given four times a day. Weight gain linearly increased while feed conversion decreased, also in a linear fashion, according to crude protein levels. Digestible energy only influenced weight gain whose best result was observed on animals fed diets containing 3,500 kcal digestyble energy. Feed conversion was not affected by levels of digestible energy. A significant interaction occurred among CP and DE levels for body composition in moisture, protein and lipids. Levels of 35% of CP and 3,500 kcal of DE provide better zootechnical results without affecting chemical composition of carcass of piavucu fingerlings, so the suggested energy:protein ratio is 10 kcal/g CP.

Proteína e energia na dieta de jundiás criados em tanques-rede

The objective of this study was to evaluate the influence of two levels of digestible energy (3250 and 3500 kcal kg-1) in conjunction with three levels of crude protein (25, 30 and 35%) on the productive performance of catfish (Rhamdia voulezi) juveniles. Two-hundred and forty catfish juveniles with 95.55±6.70 g average weight and 20.43±1.13 cm total length were randomly assigned into twenty-four 370 L-cages, in a factorial arrangement with six treatments and four reptitions. Feeding was performed four times a day, ad libitum. At end of experimental period, the factorial analysis of variance showed significant influence with respect to the different parameters evaluated. The fish fed with diets of 30% crude protein and 3,250 kcal digestible energy kg-1 of diet presented the best results. Therefore, diets with at least 30% crude protein and 3,250 kcal digestible energy kg-1 are recommend for catfish juveniles.