双齿围沙蚕对饲料中氮元素的利用及其与体质量和温度的关系

The utilization of dietary nitrogen related to body quality and temperature in sluge worm Perinereis aibuhitensis

对不同体质量双齿围沙蚕Perinereis aibuhitensis在不同温度条件下对牙鲆配合饲料中氮元素的利用和氮收支进行了研究。试验按沙蚕体湿重设置(0.40±0.19)、(1.00±0.22)、(2.00±0.50)g 3个组,分别记为S、M和L组,每组分别设16、20、24℃3个温度梯度。结果表明:1)20℃时各组双齿围沙蚕对氮的摄食率均达到最大值,平均为17.0 mg/(d.g),变幅为14.3～22.0 mg/(d.g);2)双齿围沙蚕于不同温度下对氮的摄食率均随体质量的增加而降低,其中,S组为10.5～22.0 mg/(d.g),M组和L组则分别为8.0～14.7、6.6～14.3 mg/(d.g),氮摄食率与体质量的关系可用幂函数式CN=aWb表示,其中a值在20℃时最高,为10.618,b值为-0.2076～-0.1911;3)双因素方差分析表明,温度和体质量对沙蚕的氮摄食率均有极显著影响(F=79.125,P<0.001;F=34.308,P<0.001);4)在本试验条件下,双齿围沙蚕对饲料中氮的累积率平均为11.8 mg/(d.g),以摄食氮为100%计,累积氮所占的比例最大,平均为88.99%,排粪氮次之,为9.43%,而排泄氮所占的比例最低,仅为1.58%。

Nitrogen utilization and nitrogen budget were studied in sluge worm Perinereis aibuhitensis with body weight of（0.40±0.19）g（Group S）,（1.00±0.22）g（Group M）,and（2.00±0.50）g（Group L） collected from seaside of Zhuanghe,Dalian,Liaoning Province,reared in 10 cm thick sand tanks with circulating water,and fed flounder feed,at various temperature of 16,20 and 24 ℃.1）The nitrogen consumption of the sluge worm was found to be ranged from 14.3 mg/（d·g）to 22.0 mg/（d·g）,with average 17.0 mg/（d·g） at 20 ℃,higher than that at 16 ℃ and 24 ℃.2）At the same water temperature,the nitrogen consumption was depressed with increase in body weight,from 10.5 mg/（d·g）to 22.0 mg/（d·g） in Group S,from 8.0 mg/（d·g）to 14.7 mg/（d·g） in Group M,and from 6.6 mg/（d·g）to 14.3 mg/（d·g） in Group L.The relationship between nitrogen consumption [CN,mg/（d·g）] and the body weight（W,dry body weight,g） was expressed as CN=aWb,with the maximum a of 10.618 at 20 ℃,and the b value from-0.2076.3 to-0.1911.The nitrogen consumption were significantly affected by temperature（F=79.125,P0.001） and body weight（F=34.308,P0.001）.4）Under the experimental conditions,the average nitrogen budget was expressed as 100CN=88.99PN＋1.58UN＋9.43FN,with the average nitrogen retention of 11.8 mg/（d·g）.