Effect of stocking density on growth performance, survival and production of Catla catla and Labeo rohita during nursery rearing in cages.

Abstract

A nursery rearing experiment of fry to fingerlingwas conducted in cages in Dimbhe reservoir of Pune Dis-trict of western India, located at 19060N, 73440Etoevaluate optimum stocking density for better growth per-formance and production of Indian Major Carps, Catla(Catla catla) and Rohu (Labeo rohita) using formulatedfeed with 36% protein. The culture experiment was carriedout in triplicate for the period of 115 days. Catla and Rohufry of 36 ±1.75 mm were stocked in four differentstocking densities viz T1(900 no), T2(1800 no), T3(2700no) and T4(3600 no) in 18 m3water spread area of39393 m sized cages. The composition of catla androhu was 55 and 45%, 47 and 53%, 40 and 60% and 43 and57% in T1;T2;T3and T4respectively. Results of the studyfound significantly (p \ 0.05) highest mean length(145.65 ±2.70 mm), mean weight (57.33 ±3.31 g),specific growth rate (3.76 ±0.22%) and survival (65.5%)in T1as compared to other (T2;T3and T4) experimentaltrials. The highest production in terms of number (1239nos) and biomass (49.64 kg/cage) was significantly(p \ 0.05) higher in T4with its mean length and meanweight (115.23 ±3.73 mm and 37.34 ±1.45 g). Thestudy suggests that stocking density of 3600 nos of fry/27 m3produces maximum fingerling of [100 mm] size in115 days in cages. These findings aid in providing guide-line for stocking density of fry rearing in nursery cages toimprove sustainability of freshwater carp farming in cages.