池养大海马的摄食、生长和生态转换效率

The ingestion,growth and ecological conversion efficiency of Hippocampus kuda under the intensive rearing conditions

对大海马 (平均体长 92 .82± 2 .0 5 2 6mm ,平均体重 6 .6 9± 0 .4 5 70g)在养殖条件下 (放养密度为 2 0 0ind·m-3 ,溶解氧保持在 5 .5mg·L-1以上 ,生物耗氧量低于 3mg·L-1,pH值 7.5～ 8.2 ,透明度 5 0～ 85cm ,盐度 15 .2～ 2 6 .5 )的摄食、生长和食物生态转换效率进行了定量研究。通过系统取样 ,测量海马的全长、体重和消化道内食物重量 ,计算其增长速度、摄食率、消化道排空率、生态转换效率等数值 ,发现大海马的摄食每天有两个摄食高峰 ,即 12 :0 0和 18:0 0 ,晚上不摄食或很少摄食。大海马的日摄食量为 16 .6 342± 0 .782 0g·(10 0g) -1,日摄食率为 1177.2 5cal·ind-1,排空率 0 .14 4 4g·(10 0g) -1·h-1,食物转换效率 2 0 .0 4 % ,能量转换效率 31.4 2 %。体长日平均增长速度和日均增长率分别为 1.176 6mm和 1.2 7% ;体重日平均增重速度和日均增重率分别为0 .182 0g和 2 .2 7%。通过多元回归分析建立摄食率与体重及温度的相关关系 ,得出下列关系式 :C =6 .75 4 4+0 .30 14T +0 .2 190W (F =83.5 96 3,F0 .0 1=18.0 0 ,F >F0 .0 1)。

Hippocampus kuda Bleeker is an official oceanic fish in Chinese traditional medicine. Because of the great contradiction between supply and need, the nature resources of Hippocampus kuda Bleeker have declined sharply. The food consumption, growth and ecological conversion efficiency of H. kuda were studied in the Commercial Rearing Base Guangdong Richvast, the South China Sea, Guangdong Province. The Elliott Persson model and Eggers model were used to determine its feeding periodicity, to quantify its food consumption quantity, consumption rate,evacuation rate and food as well as energy conversion efficiency. The results indicated that seahorse (the range of body length 88.5-141.3mm, body weight 5.75-13.27g wet) fed in daytime with two peaks in 12:00 and 18:00 and were not fed in nighttime (the density is 200 ind·m -3 , DO is beyond 5.5mg·L -1 , BOD is below 3mg·L -1 , pH is 7.5-8.2, transparency is 50-85cm, salinity is 15.2-26.5). The mean daily food consumption of H. Kuda was 16.634 2±0.782 0g·(100g) -1 per day. The food consumption rate was 1 177.25 cal·ind -1 per day and evacuation rate was 0.144 4g·(100g) -1 ·h -1 . Its food and energy conversion efficiency was 20.04% and 31.42% respectively. The mean growth speed of its body length and daily growth rate was 1.176 6mm per day and 1.27% respectively .The mean body weight growth speed of H.kuda and daily body weight growth rate were 0.182 0g per day and 2.27% respectively. The food consumption of seahorse correlated with enviromental water temperature significantly (P<0.01). It can be expressed by the formula:FC=0.458 4+0.626 8T(P<0.01).The relationship between the food consumption rate and its body weight as well as water temperatuer can be experssed better by the formula C=6.754 4+0.301 4T+0.219 0W(F=83.596 3 F 0.01 =18.00 F>F 0.01) ).