influence of caspian gammarus on growth parameters, survival and serum biochemical factors in jewel fish (hemichromis bimaculatus

abstract this investigation was conducted to replace artificial food with gammarus and study this effect on survival and growth parameters of jewel in case of completely randomized design with 3 treatments and 3 replicates in each treatments. 270 jewel fishes with initial mean weight of 1.22±0.72 were reared in 9 aquariums (30 fishes in each aquarium) with volume of 100 liter water. experimental diets were including: 1) gammarus 2) commercial pellet and gamarus alternatively 3) commercial pellet (control diet). fish were fed with the experimental diets to apparent satiation 4 times daily. at the end of experiment, growth parameters were estimated by the initial and final weight and hematology parameters were measured. results showed significant differences for increased body weight and specific growth rate (p<0.05), but there were no significant differences for feed conversion ratio, conditional factor and survival rate between treatments (p>0.05). increased body weight and specific growth rate was higher in control diet among treatments. gammarus made significant differences on blood and biochemical factors such as hematocrit, hemoglobin, mch, mcv, mchc and triglyceride (p<0.05) but, red blood cells, white blood cells and total protein have not shown significant differences (p>0.05). control diet had the higher value of hematocrit, hemoglobin, and triglyceride and lowest value of hematocrit and triglyceride was observed in gammarus while hemoglobin was lowest in treatment 2. diet containing commercial pellet and gamarus alternatively had similar growth rate and some blood parameters than that of commercial pellet, so it could be useful for rearing ornamental fish and can considered as replacement by the part of commercial food, despite the fact that gammarus could not cause to increase growth parameters as only feed.