Efeitos de dietas suplementadas com vitamina e sobre o crescimento, eficiência alimentar e parâmetros hematológicos e fisiológicos do tambaqui Colossoma macropomum (CUVIER, 1818)

The vitamin E inclusion in fish food is related to improvements in in growth performance and nonspecific immune response for different species. The present study aimed to evaluate the effect of different vitamin E levels (DL acetate-α-tocopherol, 50% active) on productive performance, hematological variables, hematometric index and physiological parameters of tambaqui (Colossoma macropomum) fingerlings. A total of 150 fishes with an average weight of 2.94 ± 0.14 g and initial average standard length of 4.29 ± 0.07 cm were distributed in aquariums (300 L) in water recirculation system, temperature of 27.13 ± 0.45 ºC, pH 7.16 ± 0.45, dissolved oxygen 7.15 ± 0.88 mg L-1, electronical conductivity 0.142 ± 0.05 (μs cm-1); ammonia 0.00 ± 0.00 (ppm) and nitrite 0.19 ± 0.25 mg L-1. The stocking density was 10 fishes per experimental unity. The inclusion levels of α-tocopherol in the diet were 0, 250, 700 and 1,000 mg kg-1. Thus, was used a completely randomized design with five treatments and three repetitions, where the fishes were fed three times a day during 90 days. The results indicate that the different vitamin E levels did not affect the productive performance of tambaqui fingerlings. However, the inclusion of 1,000 mg kg-1 of α-tocopherol reduced (P0.05) by α-tocopherol supplementation. In differential leukocyte count, there was no significant difference of lymphocyte number, monocytes and basophiles. However, the neutrophil number was greater in the control treatment (P>0.05), while eosinophil and specials granulocytic cells were better than control treatment (P0,05) pela suplementação com α-tocoferol. Na contagem diferencial de leucócitos, não houve diferença significativa no número de linfócitos, monócitos e basófilos. Contudo, a quantidade de neutrófilos foi maior no tratamento controle (P