盐度对斑点叉尾鮰幼鱼生长性能、肌肉持水力和营养组成的影响

摘要

为探明盐度对斑点叉尾鮰幼鱼生长、肌肉持水力和营养组成的影响,试验将不同家系来源的斑点叉尾鮰幼鱼混合后分别养殖在盐度为0、1、3、5、7和9 ng/L等6种水体环境中60 d,测定斑点叉尾鮰幼鱼生长性能、肌肉持水力和营养成分等指标.结果表明,盐度3和盐度5的水体中斑点叉尾鮰幼鱼生长良好,存活率均在95％左右,特定生长率分别为2.65％/d和2.59％/d.在肌肉持水力方面,随着养殖水体盐度的增加,持水力总体上呈下降趋势,盐度3组中幼鱼肌肉持水力与盐度0组总体差异性并不显著(P>0.01).在肌肉营养成分方面,随着水体盐度提高的总趋势是幼鱼肌肉中水分含量升高,灰分含量降低,粗蛋白和粗脂肪含量受到其摄食量的影响较大,盐度3组具有较高的粗蛋白和粗脂肪含量.结果表明,适当提高斑点叉尾鮰幼鱼养殖水体盐度可以显著性提高存活率,减少病虫害的发生,且对肌肉品质没有太大影响,最适宜的盐度值为3 ng/L.%The object of this study was to investigate the effect of salinity on growth and flesh quality of channel catfish fingerlings. The fish were reared at different salinity (0, 1, 3, 5, 7 and 9 ppt) for 60 days, and the growth performance, water binding capacity of muscle and muscle nutrients composition were determined. The results showed that the fish reared at salinity 3 and 5 groups with grea-ter survival rate (96. 67％ and 94. 67％, respectively) and SGR (2. 65％/d and 2. 59％/d, respectively), both of which had signif-icant differences in comparison with other salinity groups (P<0. 01). Generally, water binding capacity decreased with the increase of the salinity, but the difference of salinity 3 and salinity 0 groups was not significant (P>0. 01). In terms of muscle nutrients, with the increase of salinity, the water content in muscle increased and the ash content decreased, while the contents of crude protein and crude fat were affected by the food intake. The fish reared at salinity 3 group had higher crude protein and crude fat contents. Thus, the re-sults indicated that raise appropriately the aquaculture water salinity of channel catfish fingerlings could significantly improve the surviv-al rate, reduced the occurrence of pests and diseases, and the muscle quality could not be impacted to a certain extent. The most suit-able salinity is 3 ppt according to the present results and findings.