Effect of dietary incorporation of natural attractants on growth and survival during seed rearing of Indian butter catfish, Ompok bimaculatus

ABSTRACT

Aim: The objective of the study was to assess the effect of dietary incorporation of different feed attractants viz. tubifex, earthworm and fish meal on growth and survival of O. bimaculatus (pabda fish) fry. Methodology: Fifty numbers of fifteen days weaned fry (0.105±0.008g; 2.14±0.14cm) were stocked into each aerated aquariums (30.0 x 15.0 x 15.0 cm) following a completely randomized design (CRD) consisting of four treatments including the control with three replicates each. Four iso-nitrogenous purified diets were prepared including three treatment diets with attractants (5%) by replacing an appropriate amount of casein and cellulose and fed to the fishes twice daily. Results: Results from the study showed that growth of fry as measured by final weight, weight gain, mean daily weight gain and specific growth rate of fries were significantly (p<0.05) higher in tubifex supplemented group and lower in control group. Survival was significantly higher in tubifex supplemented group (42.66±1.3%) and lower in control group. Moreover, other yield parameters such as total biomass, condition factor and performance index also followed the same trend as survival. Further, higher protease activity was found in control group (2.233±0.038 units mg protein-1 min-1) followed by earthworm (0.354±0.031 mg protein-1 min-1) supplemented group (p<0.05). The lipase and amylase activity were higher (p<0.05) in tubifex and control groups, respectively. Interpretation: It could be concluded that the dietary supplementation of tubifex at 5% inclusion level could be a promising aquaculture feeding strategy for pabda fish due to its rich nutrient content, increased feeding stimulation and more palatability.