The experiments and model together suggest that interspecific variation in remating opportunities and clutch size may be responsible for differences in care patterns within the sub-family Tilapiini. Abstract.The study was conducted to develop guidelines for high-density overwintering of tilapia in tanks using warm underground sea water. Yearly fluctuations in size distribution were attributed to changes in the proportions of fast- and slow-growers, as well as in the abundance of year-classes. blue tilapia), Tilapia galilaea (now Sarotherodon galilaeus, Galilee cichlid), Tilapia heudeloti (now Sarotherodon melanotheron, Senegal. First year's growth, 23152mm, was closely related to final length, which appeared to be affected by genetic variation in the population. Different sizes of fish showed different absorptive capacity. Assuming a natural mortality (M) of 0.94, total stock size averaged 300700 tonnes in that period, while recruitment averaged < 0.73 million per year. Seawater-acclimated fish of 20 g were stocked in 36 tanks at 250, 500 and 750/m3. Intestinal absorption by Sarotherodon galilaeus (syn Tilapia galilaea ) of Lake Kainji. galilaeus whose body length ranged from 13.4cm and 24.1cm in IITA lake in Ibadan. Three broods hatched in years of relatively high water levels (1970, 19) yielded especially low recruitment. Ben-Tuvia (1960) reported Tilapia galilaea whose body length was 32cm as. Water flow was regulated at 0.1 and 0.2 l/kg fish/min. Between 19, catches of Tilapia galilaea in Lake Kinneret fell from an annual average of about 200 tonnes to a low of 70 tonnes in 1974, and then returned to their former level. Fish were fed at the rates of 0.75% and 1.0% of biomass per day.After 135 culture days, the mean individual weight gain and specific growth rate decreased, whereas feed conversion increased significantly (P <0.0001) with the increase in stocking density. Tilapia galilaea galilaea Linnaeus, 1758 Tilapia galilaea pleuromelas. The condition factor at 500 and 750 fish/m3 was significantly lower (P<0.0005) than at 250 fish/m3. However, stocking density had no significant effect on the survival rate. Significantly better specific growth rate, condition factor and feed conversion were observed at a water flow rate of 0.2 l/kg fish/min than at 01 l/kg fish/min. Furthermore, the fish start to be caught at 210mm through the current gillnet mesh size. ![]() Significantly higher mean individual weight gain, specific growth rate, and survival rate were observed at 1.0%/day than at the 0.75%/day feeding rate. The findings indicate that the optimum stocking density for overwintering tilapia in tanks using warm underground sea water is 750 fish/m3 with a water flow rate of 0.1 l/kg fish/min and a feeding rate of 0.75%/day.
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