Junaid Khan, Mansoor Rather, Anayitullah Chesti, Sadiya Farooq, Shahid Manzoor Mandu, Anam Aijaz and Uzma Nazir
Abstract
The study was conducted to evaluate the effect of duckweed (Lemna minor) based formulated diets on the growth Performance, , survival and proximate composition of Schizothorax niger (snow trout) in two farming systems viz in intensive and semi-intensive systems. Duck weed was incorporated at 10%, 20%, and 30% levels in a 35% protein diet designated as T1, T2, and T3 respectively. T0 or control diets had no duckweed. Schizothorax niger fry, averaging 10.5±0.12 g, were randomly distributed into four treatments and fed twice daily at 5% body weight. At the end of the 60 day rearing period, the weight gains in the intensive system were 12.67±0.13 g, 14.02±0.12 g, 11.17±0.03 g, and 10.06±0.13 g, and in the semi-intensive system were 13.84±0.25 g, 16.24±0.2 g, 12.25±0.17 g, and 10.47±0.13 g for T0, T1, T2, and T3 respectively. FCR ranged from 2.87±0.05 to 3.96±0.06, and SGR from 1.11±0.01 to 1.55±0.02 day-¹. Survival rates were 85%-97.5% in intensive and 92.5%-100% in semi-intensive systems, with the highest survival in T1. Protein and lipid content were highest in T1 (16.62±0.03%, 7.47±0.02% in intensive; 16.97±0.02%, 7.88±0.03% in semi-intensive), while ash content was highest in T3 (2.45±0.03%, 2.32±0.01%). The semi-intensive system showed better overall performance, indicating its efficiency for Schizothorax niger aquaculture with up to 10% duckweed replacing fish meal without compromising growth or survival