Efeitos da suplementação dietética com astaxantina de Haematococcus pluvialis na coloração e desempenho zootécnico do peixe ornamental Cryptocentrus cinctus

Abstract

Ornamental fish farming is a highly profitable activity that is gaining momentum due to its rapid economic returns and high added value in the market. Coloration is one of the most important criteria in ornamental fish, along with health and productivity aspects. This study aimed to produce an inert diet supplemented with biomass of the microalgae Haematococcus pluvialis, which is rich in astaxanthin, to enhance pigmentation, antioxidant activity, and zootechnical performance of Cryptocentrus cinctus. The aquafeeds were formulated with different concentrations of astaxanthin from H. pluvialis biomass: A0 (0% - control), A10 (0.01%), and A15 (0.015%), with four replicates each. Twelve fish, four for each treatment, were fed for 60 days, and the variables of water quality, growth, tegument color, and catalase activity in the animals were evaluated. The presence of astaxanthin in the diet influenced the pigmentation of the fish, with changes in color observed in treatments A10 and A15 at the end of the experimental period. The treatment with a higher concentration of astaxanthin showed an acquisition of yellow tone (R= 144.75 ± 12.7; G= 122.9 ± 12.7; B= 48.5 ± 17.6), indicating the influence of this carotenoid on the pigmentation of the fish. In addition, dietary supplementation with astaxanthin from H. pluvialis at 0.015% (A15) influenced the catalase activity, with a mean value of 25 U CAT mg-1, and the zootechnical performance of C. cinctus. The fish in this treatment had greater weight gain (0.44 g) and length (7.93 mm) and a lower feed conversion factor (1.10). Therefore, the inert diet supplemented with 0.015% astaxanthin resulted in enhanced pigmentation with the acquisition of yellowish color, greater antioxidant activity, and improved growth and feed utilization in C. cinctus.