Comparison of propagation efficiency of sobaity (Sparidentex hasta) fish rearing with fish capture from the sea in circular spawning tank

This project was conducted in imam Khomeini mariculture research state from October 2010 to June 2013 to compare reproductive performance between wild and domesticated Sobaity seabream broodstocks. In 3 years wild broodstocks did not spawn in 5 and 10 fiberglass and concrete tanks but domesticated broodstocks spontaneously spawned from February to March. In the first year domesticated broodstock in ratio of 3 females to 6 males allotted in 10 mt concrete tanks in triplicate. the about 2776000 eggs produced from 9 females and 18 males but further heavy mortality occurred because of winter shock syndrome and suppression of immunity system. Mean temperature, salinity and PH in incubation period was 16.5˚C (range between16-18˚C), 45ppt, 8.5 respectively. Mean floating eggs and hatch percent was 15.5% and 8.9% and about 19000 larvae produced. In the second year domesticated broodstock in ratio of 9 females to 23 males allotted in 5 mt fiberglass tanks in triplicate .about 17540000 eggs acquired from 27 female and 69 male broodstocks. Mean temperature, salinity and PH in culture period was 24.8 ˚C(range between20-28.3˚C), 47.5 ppt, 8.4 respectively. Mean floating eggs and hatch percent was 58.94% and 84% and about 8640000 larvae produced and stocking density was 10-30 larvae per liter. After 61 days mean production and survival were 503.3 (range between 140-1220) larvae per cubic meter and 5.3% (range between 0.47–12.2 %) respectively. Final mean weight of fry was 2.6 gr. In the third year domesticated broodstock in ratio of 3 females to 6 males allotted in 5 mt fiberglass tanks in triplicate. about 6570000 eggs acquired from 9 female and 18 male brood stocks. Mean temperature, salinity and pH in culture period was 23.9˚C(range between 19.5-28.4˚C), 45, 7.6 respectively. Mean floating eggs and hatch percent was 54.7% and 81.6% and about 2889800 larvae produced and stocking density was 10-30 larvae per liter. At the end of 87 and 89 days of husbandry the mean production and survival were 359 (range from 300 to 397) larvae per cubic meter and 2.7% (range between 1.32–3.8 %) respectively. Final mean weight of fry was 3.5 gram and Larvaeculture in the last 2 years carried out in 5 cubic meters fiberglass tanks. It seems to domesticated broodstocks because of spontaneous spawning, long spawning period, more brood stocks and possibility of reusing them in the next year are very economical for propagation than wild broodstocks