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在科威特湾中设置9只网箱(2.5m×2.5m×2.0m),饲养罗非鱼(Oreochr-omis spilurus Cünther),以探索可获得最佳产量的放养密度。鱼种入箱前已适应33×10~(-3)的盐度,以3个密度放养,即200、250和300尾/m~3。投喂鲷用沉性颗粒饲料,日投饵率随鱼的生长从6.0%降至2.5%。饲养193d后,3个放养密度的平均尾重和总产量无显著差异(P>0.05)。随着放养密度的增加,饵料系数显著增加(P<0.002),而成活率则显著降低(P<0.006)。在所有放养密度下,雄鱼的终重都显著地大于雌鱼(P<0.001)。小鱼(<250g)的肥满度显著(P<0.01)低于大鱼(>250g)。本研究表明,在该实验地点的海水网箱中饲养罗非鱼,最佳产量的放养密度为200尾/m~3。
Nine cages (2.5 m × 2.5 m × 2.0 m) were set up in the Kuwait Bay and Oreochr-omis spilurus Cünther was raised to explore stocking densities for optimal yields. The fish had adapted to the salinity of 33 × 10 -3 before entering the tank and were stocked at three densities, namely 200, 250 and 300 / m 3. Feeding seabream with pelleted feed, feed rate per day with the fish’s growth from 6.0% to 2.5%. After feeding for 193 days, there was no significant difference in the average tail weight and the total yield of the three stocking densities (P> 0.05). With the increase of stocking density, the bait coefficient increased significantly (P <0.002), while the survival rate decreased significantly (P <0.006). At all stocking densities, the final weight of males was significantly greater than that of females (P <0.001). Fatness of small fish (<250g) was significantly (P <0.01) lower than that of large fish (> 250g). The results of this study showed that the best stocking stocking density of tilapia was 200 / m ~ 3 in the seawater cage at the experimental site.