Effect of feed, manure and their combination on the growth of Cyprinus carpio (L.) fry and fingerlings

Abstract

Two field experiments, each of 120-day, were conducted in twelve earthen ponds, each with dimensions 50 x 20 x 1.0m (length x width x depth) were located at Serow Fish Farm, National Institute of Oceanography And Fisheries, Dakahlia Governorate, Egypt, with a view to study the effect of nutrient inputs (feed, manure and their combination) on the common carp ( Cyprinus carpio ) fry and fingerlings of the fish. The treatments consisted of control (C, T 1), only feed (F, T2), only manure (M, T3) and manure plus feed (M+F (T4)). Poultry manure was applied in split doses to ponds of manure treatments (M and M+F). Fry (Experiment one) and fingerlings (Experiment two) of average initial weight 0.67 g a nd 3.2 g respectively, were stocked seven days after the initial manure applica tion at 5 individuals/m2. Fish in F and M+F treatments were provided a fish meal based pelleted diet once daily in the morning at 5% of body weight. The most dominant genera of phytoplankton encountered were Microcystis , Anabaena and Microspora , while among the zooplankton, Keratella and Nauplii dominated. M+F treatment had the highest plankton biomass (P 0.05), whereas F and M+F treatments recorded lower survival (P 0.05) in experiment one, but was sign ificantly (P<0.05) different in experiment two. The increment in gross fish product ion over the control was 103.22 and 119.99% in feed, 77.30 and 59.44% in manure and 162.34 and 175.08% in M+F treatments of the two experiments respectively. Car cass protein, fat and ash contents were significantly (P<0.05) higher in the three tre atments as compared to the control.