Effects of Curcuma longa rhizome on growth, skin pigmentation, and stress tolerance after transport of Trichogaster labiosa

ABSTRACT We aimed to evaluate the effects of Curcuma longa as growth promoter, skin pigmentation enhancer, and stress reducer in diets of Trichogaster labiosa after transport. We used five diets containing 0.0, 1.0, 5.0, 10.0, and 25.0 g kg−1 of turmeric rhizome powder. We observed quadratic effects of turmeric supplementation for feed intake, weight gain, final length, and specific growth rate. The estimated amount of turmeric that decreased these variables ranged from 15.53 to 16.39 g kg−1. Quadratic effects of supplementation of turmeric for cyan and black dorsal skin coloring indices were observed, with estimated values that increased these variables equal to 15.03 and 17.44 g kg−1, respectively. After fish transport, quadratic effects of turmeric were observed for the cyan and black dorsal skin depigmentation indices, with estimated values that increased these variables equal to 13.29 and 17.04 g kg−1, respectively. These results demonstrate that supplementation with turmeric at levels up to 17 g kg−1 causes further reduction in skin color due to the stress of transport. Thus, Curcuma longa acts neither as a growth promoter nor as a stress reducer for Trichogaster labiosa. Curcuma longa does not improve the orange pattern of skin pigmentation in the strain of T. labiosa orange thick-lipped gourami.