水温对细鳞鱼幼鱼消化酶活性的影响

1在水温6℃、14℃、22℃下和180×60×50cm控温水族箱中,饲养初始鱼体质量11.3±0.94g的细鳞鱼Brachymystax lenok幼鱼21d,测定了幼鱼消化器官（胃、幽门盲囊、肝脏和肠）中的蛋白酶、淀粉酶和脂肪酶的活力。结果表明：水温14℃下胃蛋白酶活性最高,其次为水温6℃时,22℃时消化酶活性最低,显著低于前2个处理组（P〈0.05）。肠中脂肪酶活性最高,显著高于胃和肝中（P〈0.05）,其次为幽门盲囊。各消化器官脂肪酶活力均在14℃时最高,其中肠和幽门盲囊中脂肪酶活力显著高于其他2个处理组。各水温条件下,幽门盲囊中淀粉酶活性最高,其次为肠。6℃时,幽门盲囊中淀粉酶活性显著高于胃和肝脏中（P〈0.05）;14℃和22℃时,幽门盲囊和肠中淀粉酶活性显著高于胃和肝脏中（P〈0.05）,胃和肝脏中差异不显著（P〉0.05）。14℃时各消化器官淀粉酶活力最高,6℃时肝脏和肠中淀粉酶活性显著低于14℃时,其它组织中各处理组间淀粉酶活力差异不显著（P〉0.05）。

Effects of water temperature on activities of digestive enzymes in juvenile lenok Brachymystax lenok

A 21-day feeding experiment was carried out to investigate the effect of water temperature on activities of digestive protease,amylase and lipase in stomach,pyloric caeca,liver,and gut in juvenile lenok Brachymystax lenok with body weight of 11.3±0.94g cultured and fed to satiation twice（08：00,and 15：00）a day）at water temperature of ：6℃,14℃,or 22℃.The results showed that： the minimal protease activity was observed in the stomach at 22℃,significantly lower than that in the other groups（P 0.05）.The maximal activities of lipase were found in the gut and pyloric caeca at 14℃（P 0.05）.There were significantly higher activities of amylase were showed in the gut and pyloric caeca than those in the stomach and liver at 14℃ and 22℃（P 0.05）.The maximal activities of amylase were occurred in all examined digestive organs at14℃,and there were significantly lower amylase activities in the liver and gut at 6℃than that at 14℃（P 0.05）.