Dietary Enhancement of colour in the Swordtail Xiphophorus hellerii.

Abstract- This study was conducted to evaluate the dietary enhancement of colour in the swordtail, Xiphophorus hellerii, supplemented with Orange peel, Pumpkin and Papaya. Completely randomized design was employed for the study. Fish with mean size group ranging from 0.66 g to 0.75 g were used for the study. The experiment was carried out in 12 FRP tanks of 80 L capacity. Each diet was fed to fish in a set of three tanks each. Fishes were stocked at the rate of 10 per tank. Three test diets namely T1, T2 and T3 with 5% of carotenoid pigment sources were formulated. Diet T1 had 5%, T2 had 5% and T3 had 5% of Orange peel, Pumpkin, Papaya respectively, and the diet without supplementation of carotenoids source served as the control (T0). Growth response as well as water quality parameters were monitored at fortnightly intervals. The growth was highest in papaya supplemented diets followed by orange peel and pumpkin supplemented diets. The average fortnightly gain in colour, growth and water quality parameters for each treatment were analysed using two way analysis of variance within three replications. Water quality parameters was observed to be within the acceptable range of the cultured species and all the three test diets showed significantly different growth from the control fish. Significant enhancement in colour development was observed in fish fed all the three test diets. The intensity of colour development was highest in T2 treatment followed by T3 and T1. Fish fed the control diet showed the least colour intensity. The three pigment sources of plant origin namely Orange peel, Pumpkin and Papaya meals assessed are cheap, easily available and involve only marginal additional cost. This approach is easily adoptable at the farmer level and moreover, does not involve any adverse effects. The study showed that incorporation of 5% of Pumpkin in diet was found to enhance the coloration in Xiphophorus hellerii.