Yaghoubi Morteza, Mozanzadeh Mansour Torfi, Safari Omid, Marammazi Jasem G
Agriculture Research, Education and Extension, Iran Fisheries Research Organization (IFRO), South Iran Aquaculture Research Center, Ahwaz, Iran.
Department of Fisheries, Faculty of Natural Resources and Environment, Ferdowsi University of Mashhad, Khorasan Razavi, Iran.
Fish Physiol Biochem. 2018 Jun;44(3):853-868. doi: 10.1007/s10695-018-0475-3. Epub 2018 Feb 7.
As amino acids (AAs) are vital molecules in the metabolism of all living organisms and are the building blocks of enzymes, a 6-week feeding trial was conducted for determining the influence of dietary essential amino acid (EAA) deficiencies on pancreatic, plasma, and hepatic enzyme activities in silvery-black porgy (initial weight 4.7 ± 0.01 g) juveniles. Eleven isoproteic (ca. 47%) and isoenergetic (ca. 20.5 MJ kg) diets were formulated including a control diet, in which 60% of dietary nitrogen were provided by intact protein (fish meal, gelatin, and wheat meal) and 40% by crystalline AA. The other 10 diets were formulated by 40% reduction in each EAA from the control diet. At the end of the experiment, fish fed with threonine-deficient diet showed the lowest survival rate (P < 0.05), whereas growth performance decreased in fish fed all EAA-deficient diets, although the reduction in body growth varied depending on the EAA considered. Pancreatic enzymes (trypsin, lipase, α-amylase, and carboxypeptidase A) activities significantly decreased in fish fed the EAA-deficient diets in comparison with fish fed the control diet (P < 0.05). Fish fed with the arginine-deficient diet had the highest plasma and liver alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase levels (P < 0.05). Plasma and liver lactate dehydrogenase and superoxide dismutase showed the highest and lowest values, respectively, in fish fed the arginine and lysine-deficient diets (P < 0.05). Plasma metabolites were significantly affected by dietary EAA deficiencies (P < 0.05). The results of this study suggesting dietary EAA deficiencies led to reduction in growth performance as well as pancreatic and liver malfunction. Furthermore, arginine and lysine are the most limited EAA for digestive enzyme activities and liver health in silvery-black porgy.
由于氨基酸（AAs）是所有生物体新陈代谢中的重要分子，也是酶的组成成分，因此进行了一项为期6周的饲养试验，以确定日粮必需氨基酸（EAA）缺乏对黑鲷（初始体重4.7±0.01 g）幼鱼胰腺、血浆和肝脏酶活性的影响。配制了11种等蛋白（约47%）和等能量（约20.5 MJ/kg）的日粮，包括一种对照日粮，其中60%的日粮氮由完整蛋白质（鱼粉、明胶和小麦粉）提供，40%由结晶氨基酸提供。其他10种日粮通过将对照日粮中每种EAA减少40%来配制。在实验结束时，饲喂苏氨酸缺乏日粮的鱼存活率最低（P<0.05），而饲喂所有EAA缺乏日粮的鱼生长性能均下降，尽管体重增长的降低程度因所考虑的EAA而异。与饲喂对照日粮的鱼相比，饲喂EAA缺乏日粮的鱼胰腺酶（胰蛋白酶、脂肪酶、α-淀粉酶和羧肽酶A）活性显著降低（P<0.05）。饲喂精氨酸缺乏日粮的鱼血浆和肝脏丙氨酸转氨酶、天冬氨酸转氨酶和碱性磷酸酶水平最高（P<0.05）。血浆和肝脏乳酸脱氢酶和超氧化物歧化酶在饲喂精氨酸和赖氨酸缺乏日粮的鱼中分别呈现最高和最低值（P<0.05）。日粮EAA缺乏显著影响血浆代谢物（P<0.05）。本研究结果表明，日粮EAA缺乏导致生长性能下降以及胰腺和肝脏功能障碍。此外，精氨酸和赖氨酸是黑鲷消化酶活性和肝脏健康方面最受限的EAA。
