Performance of Nile tilapia fingerlings submitted to different levels of cottonseed meal inclusion

Abstract

With the objective of evaluating the Nile tilapia fingerlings performance submitted to different levels of cottonseed meal (CM) inclusion (0,00; 20,00; 40,00; 60,00 and 80,00%) in rations with 30,00% of digestible protein and 3000 kcal/kg of digestible energy, the experiment was carried out in the Laboratório de Aquicultura/UEM, 250 Nile tilapia fingerlings, were used, sexually reverted, divided in 25 tanks with 150 L, in a completely randomized design with five treatments and five replications. The evaluated variables were diary weight gain (DWG), feed gain (FG), protein efficiency rate (PE), survival (S), hepatic-somatic index (HSI), condition factor (CF), dry matter (DM), protein in the carcass percentage (PC) and fat in the carcass percentage (FP). The medium values of temperature, dissolved oxygen, electrical conductivity and pH during the experimental period, were 26,93 ± 0,29oC; 5,47 ± 0,86 mg/L; 245,80 ± 54,29 µS/cm and 7,78 ± 0,19, respectively. The WG and PE presented linear decrease when the CM was included in the ration, the FG and HSI presented linear increase. The DM, PC and WG presented quadratic effect with point maxim to 45,25, 47,84 and 45,15, respectively. The S and CF didn't present significative differences (P>0,05). Concluded that the cottonseed meal influences in a negative way the Nile tilapia fingerlings performance.