Studies on growth performance of metals mixture stressed Cirrhina mrigala in earthen ponds

The whole experiment was conducted in two phases. During phase-I fingerlings of Cirrhina mrigala were divided into two groups, one group was exposed to sub-lethal concentration of metals mixture (Fe, Zn, Pb, Ni, Mn) while other was kept un-stressed as control in glass aquaria for 30 days. During stress period fish (unstressed) showed significantly better growth, fork and total lengths as 2.24g, 6.11 and 6.95mm, respectively. At the end of phase-I, both stressed and control fish were shifted to earthen ponds for phase-II study the growth parameters in semi-intensive culture for a period of six months. The ponds were fertilized with poultry droppings at the rate of 0.16g nitrogen per 100g net fish weight daily. During each trial, fish was fed daily at the rate of 2% body weight (6 days a week) with the feed of digestible energy equal to 2.90 Kcal.g-1 and 35% digestible protein. Analysis of variance revealed that only months had statistically significant effect on growth perfor