Effect of similar feeding regime on growth and body composition of Indian major carps (Catla catla, Cirrhinus mrigala and Labeo rohita) under mono and polyculture

Growth performance and body composition of yearling Indian major carps (Catla catla, Cirrhinus mrigala and Labeo rohita) was evaluated in semi-intensive (mono and polyculture) systems for 90 days. Prior to stocking, all ponds were fertilized with organic and inorganic manures. This application was repeated every two weeks throughout the study period. Supplementary feed containing 35% protein was applied daily at 3% of wet body weight. In trial 1, all the three species gained significantly higher weights with experimental feed (F1) versus control group (F0). There was non-significant difference observed among species. In trial 2, non-significant difference was observed for net weight gain among species and between feeds. The feed conversion ratio (FCR), protein efficiency ratio (PER), protein utilization (PU), gross nitrogen retention efficiency (GNRE%) and gross energy retention efficiency (GERE%) were found non-significantly different among species in both trials, except GNRE% in polyculture, where L. rohita showed significantly higher values than its counterparts. No significant difference was observed in body composition and mineral contents among species and between feeds in both trials. In conclusion, all the three fish species performed well under monoculture system with 35% protein diet and showed significantly higher growth than the control, compared to polyculture, without any significant effect on body composition.