营养强化对红螯螯虾抱卵及胚胎营养成分影响研究

Study of The Effect of Nutrient Fortification on The Egg Holding and Embryo of Cherax quadricariratus

红螯螯虾抱卵量少、孵化率低,导致其出苗量不足,这是制约其产业化发展的瓶颈之一。营养强化有助于提高亲本抱卵效果及胚胎质量。试验设置3组(1组:每日投喂亲虾两次配合饲料;2组:一周轮流投喂带鱼—配合饲料+胡萝卜—螺蛳肉—配合饲料—带鱼—配合饲料+胡萝卜—配合饲料;3组:一周轮流投喂带鱼—配合饲料+胡萝卜—带鱼—螺蛳肉—带鱼—配合饲料+胡萝卜—螺蛳肉),30 d后检测各组抱卵指标及黄卵期(原肠期至5对附肢期,呈黄色)、桔卵期(7对附肢期至18对附肢期,呈桔色)胚胎的营养成分。结果表明:①2、3组红螯螯虾的抱卵率、相对怀卵量均显著高于1组。②黄卵期胚胎的总蛋白含量显著低于桔卵期胚胎,总脂含量则显著高于桔卵期胚胎;桔卵期胚胎1组的总蛋白含量显著低于2、3组(P<0.05)。③黄卵期胚胎的必需氨基酸含量显著低于桔卵期胚胎,桔卵期胚胎3组的必需氨基酸含量显著高于其他两组(P<0.05);非必需氨基酸中,黄卵期胚胎的天冬氨酸、谷氨酸、丙氨酸、脯氨酸、酪氨酸、胱氨酸含量均显著低于桔卵期胚胎(P<0.05),1组黄卵期胚胎的胱氨酸含量显著低于2、3组,1、2组中的酪氨酸含量显著低于3组(P<0.05),3组桔卵期胚胎的天冬氨酸、谷氨酸、丝氨酸、精氨酸、胱氨酸含量显著高于1、2组(P<0.05),3组的甘氨酸、脯氨酸、酪氨酸含量显著高于1组(P<0.05)。④黄卵期胚胎的C15∶0、C18∶3n-6、C20∶5n-3(EPA)显著高于桔卵期胚胎(P<0.05);3组黄卵期胚胎的EPA、C22∶6n-3(DHA)显著高于其他两组(P<0.05);桔卵期胚胎中1组的C17∶0、C17∶1n-7、C18∶0、C18∶1n-9、C18∶2n-6、C18∶3n-3、C20∶4n-6、C20∶3n-3、EPA显著低于其他两组(P<0.05)。总之,胚胎从黄卵期发育为桔卵期,总蛋白含量升高,总脂含量降低,可能与器官的生成及之后胚体发育与胚胎孵化有关。同时,使用带鱼、螺蛳肉、胡萝卜进行营养强化可提高亲虾的抱卵率、相对怀卵量、胚胎总蛋白含量、大部分氨基酸与脂肪酸含量,促进亲虾的性腺发育。

The lack of emergence caused by the small amount of eggs and low hatching rate of Cherax quadricariratus is the bottleneck problem restricting its industrialization development.Nutritional fortification is helpful to improve the egg holding effect and embryo quality.Three groups were set up in the experiment(group 1:fed compound diet twice a day;group 2:fed hairtail-artificial diets+carrot-snail meat-artificial diets-hairtail-artificial diets+carrot-artificial diets every week;group 3:fed hairtail-artificial diets+carrot hairtail snail meat-hairtail-artificial diets+carrot-snail meat every week).After 30 days,the egg holding indexes and the nutritional components of embryos(yellow embryo:gastrula stage to five pairs of appendages,orange embryo:seven to eighteen pairs of appendages)were statistically detected.The results showed that:①the egg holding rate and the relative number of pregnant eggs in groups 2 and 3 were significantly higher than those in group 1(P<0.05).②The total protein content of yellow embryos was significantly lower than that of orange embryos(P<0.05),while the total lipid content was significantly higher than that of orange embryos(P<0.05).The total protein content of orange embryo of group 1 was significantly lower than that of group 2 and 3(P<0.05).③The content of essential amino acids in yellow embryos was significantly lower than that in orange embryos(P<0.05).The content of essential amino acids of orange embryos in group 3 was significantly higher than that in the other two groups(P<0.05).Among the nonessential amino acids,the contents of asparate,glutamate,alanine,proline,tyrosine and cystine in yellow embryos were significantly lower than those in orange embryos.The contents of cystine in group 1 of the yellow embryos were significantly lower than those in groups 2 and 3,and the tyrosine in groups 1 and 2 were significantly lower than those in group 3(P<0.05).The contents of aspartate,glutamate,serine,arginine and cystine in group 3 of orange embryos were significantly higher than those in groups 1 and 2(P<0.05),the contents of glycine,proline and tyrosine in group 3 were significantly higher than those in group 1(P<0.05).④The C15∶0,C18∶3n-6,EPA of yellow embryos were significantly higher than those of orange embryos(P<0.05).In yellow embryos,the EPA and DHA of group 3 were significantly higher than those of the other two groups(P<0.05).In orange embryos,the C17∶0,C17∶1n-7,C18∶0,C18∶1n-9,C18∶2n-6,C18∶3n-3,C20∶4n-6,C20∶3n-3,EPA of group 1 were significantly lower than those of the other two groups(P<0.05).In conclusion,when the yellow embryo develop to the orange embryo,the total protein content increase,while the total fat content decrease,which may be relate to the formation of organs and subsequent embryo development and embryo hatching.Besides,adding hairtail,snail meat and carrots for nutritional fortification will help improve the egg holding rate and relative egg holding capacity of parents,and will also significantly promote the increase of the total protein content of embryos,most amino acids and fatty acids,and promote the gonadal development of parents.