pH值对大菱鲆生长及鱼体生化组成的影响

Effects of pH on Growth and Biochemical Indices of Juvenile Turbot(Scophthalmus maximus)

研究不同pH对大菱鲆（Scophthal musximus）幼鱼生长及一般生化组成的影响。结果发现：不同时间段内，饲料利用率（FCR）总是随环境pH升高而呈上升趋势，特定生长率（SGR）及增重率（WGR）随环境DH升高而呈下降趋势。在不同时间段，pH83与pH88组的FCR均高于其他组，差异有统计学意义（P〈0.05），而SGR、WGR均低于其他组，差异有统计学意义（P〈0.05）。各组间鱼体水分差异无统计学意义（P〉0.05）；脂肪含量总体呈下降趋势，pH63组的脂肪含量高于其他组，差异有统计学意义（P〈0.05），pH6．8至7．3之间时差异不具统计学意义（P〉0.05），pH78至8．8时降低，差异有统计学意义（P〈0.05）；蛋白含量在pH6．3至7．3之间时差异无统计学意义（P〉0.05），pH7．8至88时降低，差异有统计学意义（P〈0.05）；灰分含量在DH6．3至7．3之间时差异无统计学意义（P〉0.05），pH7．8至88时升高，差异有统计学意义（P〈0.05）。结果表明，水环境pH在6．3～7．3范围内有利于大菱鲆幼鱼的健康生长。

The variation of growth and common biochemical indices of juvenile turbot （Scophthalmus maximus） under different water pH were studied. The results showed that, in different time periods, the feed consumption ratio （FCR） increased, while the specific growth ratio （SGR） and the weight gain ratio （WGR） decreased with increasing pH. Regarding FCR, the ratios of pH 8.3 and pH 8.8 groups were significantly higher than that of other pH groups （P 〈 0.05）, and the SGR and the WGR ofpH 8.3 and pH 8.8 groups were significantly lower than those of other pH groups （P 〈 0.05）. The moisture did not differ significantly in the six pH group （P 〉 0.05）. The crude fat of the whole body had a decreased trend with pH increasing, and the highest level was found at pH 6.3, and had evident differences compared with other pH groups （P 〈 0.05）, and no significant differences were found from pH 6.8 to 7.3 （P 〉 0.05）, but the content decreased significantly from pH 7.8 to 8.8 （P 〈 0.05）. As to the crude protein, no significant differences were observed from pH 6.3 to 7.3 （P 〉 0.05）, but the value significantly decreased from pH 7.8 to 8.8 （P 〈 0.05）. The content of ash had no significant differences from pH 6.3 to 7.3 （P 〉 0.05）, but increased significantly from pH 7.8 to 8.8 （P 〈 0.05）. To sum up, the results showed that pH 6.3 - 7.3 were regarded as the optimum range for the growth of juvenile S. maximus.