不同剂型和剂量的维生素C对幼刺参生长的影响

The effects of dietary vitamin C sources and levels on growth in juvenile sea cucumber(Apostichopus japonicus)

在水温11．0～14．0℃条件下，将平均体质量2．29g的幼刺参（Apostichopus japonicus）随机放入39个容积50L塑料水槽中，投喂以玉米蛋白为蛋白源，分别添加0、500、1000、2000和4000mg／kg Vc-2-三聚磷酸酯（L—ascorbyl-2-polyphosphate，LAPP）、Vc-棕榈酸酯（L—ascorbyl palmitate，LAP）和Vc-磷酸酯镁（L-ascorbyl-2-monophosphate-magnesium，APM）的13种饲料。90d的饲养情况表明，摄食添加Vc饲料的刺参的生长、蛋白质效率均显著高于摄食未添加Vc的幼参（P〈0．05）。摄食添加LAPP饲料幼参的特殊生长率最高（0．21％／d），添加LAP（0．17％／d）的次之，添加APM（0．15％／d）的最低，分别比对照组（0．12％／d）高75．00％、41．67％和25．00％。摄食添加LAPP饲料幼参的平均蛋白质效率最高（12．57％），摄食添加LAP饲料的（7．76％）次之，摄食添加APM（6．86％）的最低，分剐比对照组（5．52％）高127．72％、40．58％和24．28％。在3种剂型Vc组中，饲料系数由低到高依次为：LAPP〈LAP〈APM。饲料中LAPP、APM和LAP的添加量为2000-2500mg／kg、1000～1500mg／kg和2000～3125mg／kg时，幼刺参对饲料蛋白的表观消化率最高，生长最快，饲料系数最低。

Few studies have been reported on effects of dietary vitamin C sources and levels on growth of juvenile sea cucumber （Apostichopus japonicus）, though vitamin C as an essential micronutrition for animals is widely added to feed in fish and shrimp. The sea cucumber juveniles averaging 2.29 g in body weight were randomly stocked into 39 plastic tanks of each 45 cm× 31 cm× 30 cm at rate of 15 individuals per tank and fed formulated feed containing 7.63% crude protein （corn gluten as only protein source） and 3.89% crude fat supplemented with 5 levels （0 mg/kg, 500 mg/kg,1 000 mg/kg, 2 000 mg/kg and 4 000 mg/kg diet） of L-ascorbyl-2-polyphosphate （LAPP）, L-ascorbyl palmitate （LAP） or L-ascorbyl-2-monophosphate-magnesium （APM） to investigate the effects of dietary vitamin C sources and levels on the growth of the juveniles with triplication at water temperatures of 11. 0 ～14. 0℃ for 90 days. The higher specific growth rate （SGR）, protein efficiency ratio （PER）, and lower feed conversion ratio （FCR） were found in the juveniles fed the diets supplemented with the vitamin C than those in the juveniles in the control groups （P〈0. 05）. The juveniles fed the diets supplemented with LAPP （0. 21（K/d）） had the maximal SGR （0.21（%/d））, followed by the juveniles （0.17（%/d）） fed the diets supplemented with LAP and the next in the juveniles （0.15（%/d）） fed the diets supplemented with APM, 75.00%, 41.67% and 25.00% higher than those in the control groups. There were the maximal PER in the juveniles fed the diets supplemented with LAPP （12. 57%）, followed by the juveniles fed the diets supplemented with LAP （7.76%） and the next in the juveniles fed the diets supplemented with APM （6. 86%）, 127.72%, 40. 58% and 24.28% higher than those in the control groups （5.52%）. The FCR was in a descendent order arranged for the vitamin C＇s as follows： LAPP〈LAP〈APM. Second-degree polynomial regression revealed that the maximal apparent digestibility of dietary protein, SGR and minimal FCR were observed in the juveniles fed the diets supplemented with LAPP at a rate of 2 000～2 500 mg/kg, APM 1 000～1 500 mg/kg and LAP 2 000～3 125 mg/kg. The results come to the conclusion from the improvement of growth in the sea cucumber that the optimal dietary vitamin C micronutrition is of LAPP.