Comparative study on the performance of genetically improved rohu Jayanti and native rohu, Labeo rohita fingerlings reared in biofloc system

The experiment was designed to compare the growth performance, haematological parameters, digestive enzyme activities, carcass composition and survival of genetically improved Labeo rohita (Jayanti rohu) and native Labeo rohita fingerlings rearing under the biofloc system. One ccomparative experimental trial of 60 days was carried out using pearl-millet as a carbon source with a C/N ratio of 15:1 along with control. Results showed that the average TAN (mg/l) was significantly lower in biofloc treatments as compared to control. The growth of Jayanti rohu was significantly higher in biofloc treatments. Further FCR was also found significantly lower in Jayanti rohu as compared to native rohu. Better survival was found in BFT treatments as compared to control. Jayanti rohu showed the highest survival (100%) compared to native rohu (96.66%). Jayanti rohu exhibited the highest average body weight gain (4.30 +/- 0.06) and the lowest FCR (0.91 +/- 0.01) in biofloc based system as compared to weight gain (3.46 +/- 0.04) and FCR (1.17 +/- 0.01) of native rohu. Enzymes viz. amylase, protease and lipase showed significantly higher activities in Jayanti rohu as compared to native rohu in the BFT treatment, whereas, haematological parameters were also found significantly higher in Jayanti rohu and native rohu in BFT treatment compared to control. Carcass composition of the Jayanti rohu showed significantly higher protein level (21.53 +/- 0.39) and lipid level (0.96 +/- 0.02) as compared to native rohu. The study revealed that, genetically improved Labeo rohita (Jayanti rohu), appears to be a better suitable strain to culture under BFT systems compared to native rohu.