单环刺螠摄食节律的研究

Feeding rhythm of echiuran worm Urechis unicinctus

为研究人工养殖条件下单环刺螠Urechis unicinctus的摄食节律,试验中将粉末状饲料与水按1∶10混合均匀后形成浊液,用分光光度法测定其浊度变化,通过计算每个时段投饵1 h后养殖水体因单环刺螠摄食造成浊度的改变值,来获得各时段单环刺螠的摄食强度。结果表明:单环刺螠不同时段的摄食强度具有极显著性差异(P<0.01);一天中单环刺螠摄食最高峰出现在18:00,次高峰为6:00,且6:00、18:00两个时段的摄食强度显著高于其他时段(P<0.05);摄食最低峰出现在3:00,次低峰为21:00,此2个时段的摄食强度显著低于其他时段(P<0.05),单环刺螠摄食无明显的昼夜节律(P>0.05)。本研究结果可为单环刺螠的投喂策略提供科学参考依据。

The suspension of dietary powder containing 14.0 % of crude protein mixed with water was fed to echiuran worm Urechis unicinctus with body weight of（ 5.69±0.60） g at water temperature of（ 22±1） ℃ and change in turbidity in the water was measured by spectrophotometry 1 h after feeding in each group to evaluate feeding rhythm of the echiuran worm in artificial culture. The results showed that there were very significant differences in feeding intensity at various time（ P〈0.01）,the peak at 18： 00,followed by at 6： 00 in the morning,and significantly higher at 6： 00,9： 00 an 18： 00 than the other time（ P〈0.05）.The minimal feeding intensity was observed at 3： 00,followed by at 21： 00,significantly lower than the other time（ P〈0.05）,without diurnal feeding rhythm（ t = 0.758t0.05,6= 2.447,P〈0.05）. The findings will provide scientific reference for feeding tactics of echiuran worm.