中华绒螯蟹对赖氨酸、蛋氨酸和精氨酸的需要量

Lysine,methionine and arginine requirements of juvenile Chinese mitten crab(Eriocheir sinensis)

试验以酪蛋白、白鱼粉、豆粕和晶体氨基酸为蛋白源,配制了15组试验饲料,分别测定了中华绒螯蟹幼蟹对赖氨酸(Lys)、蛋氨酸(Met)和精氨酸(Arg)的需要量。养殖试验在室内玻璃纤维水族缸中进行,试验水温为(28±3.0)℃,pH为7.4左右,试验周期为56d。试验组1～试验组5为Lys试验,试验组6～试验组10为Met试验,试验组11～试验组15为Arg试验,试验用蟹平均初重分别为:Lys试验(2.050±0.027)g,Met试验(2.027±0.033)g,Arg试验(2.05±0.032)g。每个试验设5个氨基酸梯度,其中Lys梯度为:1.58%、1.98%、2.38%、2.78%和3.18%;Met梯度为:0.50%、0.75%、1.00%、1.25%和1.50%;Arg梯度为:1.39、2.09、2.79、3.49和4.19%。每个梯度设3重复。试验结果表明,Lys试验中,试验组3(含2.38%Lys)获得最大的增重率和特定生长率,但与试验组2(1.98%Lys)和试验组4(2.78%Lys)之间没有显著性差异;且试验组3的全蟹水分含量显著较低,而蛋白质含量显著较高(P<0.05)。Met试验中,试验组8(含1.00%Met)的增重率和特定生长率显著较高(P<0.05),而其它试验组的增重率和特定生长率差异不显著(P>0.05);试验组10全蟹水分含量显著较高,而粗蛋白含量显著较低(P<0.05)。Arg试验中,试验组14(日粮含3.49%Arg)的增重率和特定生长率显著高于其它试验组(P<0.05);而各试验组间全蟹营养组成均没有显著性差异。根据试验的生长反应和二次曲线回归分析,确定了中华绒螯蟹幼蟹饲料中最适赖氨酸、蛋氨酸和精氨酸的需要量分别为2.34%,1.12%和3.62%。

Three experiments were conducted to determine the lysine, methionine and arginine, requirements of juvenile Chinese mitten crab Eriocheir sinensis. The juvenile crab [ average initial weight： Lys experiment （2. 050 ± 0.027 ） g; Methionine experiment （ 2. 027 ± 0.033 ） g; Arginine experiment （ 2.05 ± 0.032 ） g ] were fed amino acids test diets for 56 days with the protein source containing casein, white fishmeal, soybean meal and crystalline amino acids. The test diets contained 5 graded levels of lysine （ 1.58%, 1.98%, 2.38%, 2.78% and 3.18% ）, methionine （0.50% ,0.75%, 1.00%, 1.25% and 1.50% ） and arginine （ 1.39%, 2.09% ,2.79% ,3.49% and 4.19% ） respectively. The triplicate feeding trials were conducted in fiberglass tanks indoor. Water temperature and pH were kept at （28 ± 3.0） ℃ and 7.4, respectively. The results of the lysine experiment showed crab fed diet 3 containing 2.38% lysine had the best weight gain （WG） and specific growth ratio（ SGR）, but no significant difference was found between the levels of 1.98% （ diet 2 ） to 2.78% （ diet 4 ） ; the whole crab fed diet 3 had significantly low moisture and significantly high protein content（ P 〈 0. 05 ）. The results of methionine experiment showed crab fed diet 8 containing 1. 00% methionine had significantly high WG and SGR（ P 〈 0.05 ）, no significant difference was found in other test groups; the crab fed diet 10 （1.5% methionine）had significant high moisture content and low protein content of whole body （ P 〈 0.05） ; no significant difference was found among the other test diets （ diet 6 to diet 9 ）. The results of arginine experiment showed crab fed diet 14 containing 3. 49% arginine had significant high WG and SGR （ P 〈 0.05） ;but no significant difference for the body composition of crab was found. Based on the growth response and quadratic model regression analysis of the relationship of WG with dietary Lys, Met or Arg levels, the Lys, Met and Arg requirements of juvenile Chinese mitten crab were estimated to be 2.34% ,1.12% and 3.62% respectively.