Study the production performance of carp poly-culture in earthen ponds at BAPARD by using natural feeds in winter season

Abstract

An experiment was conducted to compare the production performances of different carps i.e. Rohu (Labeo rohita), Catla (Catla catla), Mrigal (Cirrhinus cirrhosus) and Silver carp (Hypophthalmicthys molitrix) in different stocking densities of poly-culture by using natural feeds in winter season. Three treatments each with three replications were maintained and the stocking densities of carps were 32, 64 and 128 per decimal in T1, T2 and T3 respectively. The ratio of stocking for Rohu, Catla, Mrigal and Silver carp were 5:1:1:1. The water quality parameter such as pH, temperature, dissolved oxygen and transparency were observed fortnightly. The obtained results showed that the highest weight was gained at 470.12±0.76 g in treatments T1 by Silver carp, followed by Mrigal (401.70±0.31g), Catla (410.10±0.30 g) and Rohu (450.10±0.30 g). Similarly, the highest length was obtained in treatment T1 by Silver carp at 37.10±0.30 cm followed by Rohu at 25.75±1.13 cm Catla at 28.47±2.50 cm and Mrigal 24.33±1.20 cm. However, both the weight gain and the length gain were the lowest in treatment T3 for all species. On the other hand, the highest SGR% was found in treatment T2 for Mrigal (2.10) and the lowest SGR% was in T3 for Rohu (1.37). The highest survival (%) of the fishes was found in treatment T1 than those of treatments T2 and T3. Furthermore, the highest production was obtained in treatment T3 (12.35 kg/dec.) followed by T2 (11.56 kg/ dec.) and T1 (10.19 kg/dec.). The BCR was calculated 1:1.28 for T1, 1:0.75 for T2 and 1:0.03 for T3. The findings of this experiments revealed that among three treatments, the stocking density 32 per decimal (T1) is the most suitable.