بررسي اثر سه جيره غذايي برگ د رخت بر بازماند گي Gammarus komareki د ر شرايط آزمايشگاهي

The effect of three kind of plant leaf as a feed on survival of amphipod (Gammarus komareki)

A compeletly randomized design was conducted to determine the effect of three kind of plant leaf as gammarus feeds (Plane: Platanus orientalis; Alder: Alnus glutinosa and mixed of Plane and Alder) on survival of amphipod (Gammarus komareki) during a 1-month culture in a water recirculating system. The specimens of gammarus were gathered from the Shour River in the area of Eshtehard in province of Tehran, Iran, then transported to lab of Department of Fisheries and Environmental Sciences, Natural Resources Faculty of University of Tehran. The experimental unit was consisted of an aquarium with the capacity of holding 30 L water, a trough (30 cm length, 25cm width and 10cm depth) and an aquarium pump with the power of pumping 5L of water per minute to recycle the water through the aquariums and troughs. At the start of the experiment, each aquarium filled with 30 L of brackish water (salinity of 9 ppt), then 20 pieces of Gammarus komareki with the average weight of 10±1.11 mg were introduced into each trough. The specimens were fed dry experimental leaf with the rate of 0.5 g /unit. The old leaf was replaced fresh dry leaf during the experimental period. Water temperature and pH ranged 24-28oc and 7.49-8.23, respectively during the experiment. Concentration of hardness, calcium, total nitrogen, carbonate and bicarbonate decresed during the experimental period. The survival of gammarus was significantly different (p<0.05) among treatments. This rate in treatment with plane leaf was higher compared to other treatments. The result of this study indicated that Gammarus komareki fed plane leaf better than alder leaf and mixed of plane and alder.