Study on feasibility of rearing integrated native fish of Shizotorax zarudnyi with chianies carp on Sistan area

Present study carried out in 6 earthen ponds (3500 m^2 each) at the Zahak fish propagation and cultivation center. In July 2005 ponds were prepared and stocked with 1100 fish specimens with 40 g average weight. Stocking normative in two ponds (1 and 4) were 220 common carp, 110 grass carp, 715 silver carp, and 55 big head specimens. In the next two ponds (5 and 6) common carp reduced to 50% and Shizotorax zarudnyi was replaced. In the rest two ponds (7 and 8) common carp reduced to zero and totally replaced with Shizotorax zarudnyi. Manure and inorganic fertilizer were used during cultivation period. Carp was fed by concentrated food and grass carp was fed by alfalfa. At the end of the cultivation period (16 months) mean weights of common carp, grass carp, silver carp, big head, and Shizotorax zarudnyi reached 1201 g, 1572 g, 313 g, 486 g, 531 g respectively. Mean daily growth were 2.41 g, 3.19 g, 0.56 g, 0.92 g, 1 g respectively. Survival rate during cultivation period were 97.57%, 68.3%, 94%, 85.45%, 46.85% respectively. Biological parameters were recorded once a month. Other chemical and physical parameters such as air and water temperatures, oxygen, pH, twice per day and factors such as nitrite, nitrate, Ammoniac, transparency, salinity and phosphate were measured and recorded once per week. During cultivation period average pH was 7-10.34, water temperature was 0.5-33 °C, transparency was 12-115cm, salinity was 1.1-5 mg/l, oxygen was 2-10 mg/l, nitrite was 0.86-0.16 mg/l, nitrate was 0.06- 2.21 mg/l, and phosphate was 0.1-1.8 mg/l. Average total yields in the ponds 1 and 4 with standard normative for the region were 554, and 623 kg. In the ponds 5 and 6 with 50% Shizotorax zarudnyi were 514 and 518 kg, and in the ponds 7 and 8 with total Shizotorax zarudnyi replacement were 533 and 386 kg