Blom J H, Dabrowski K
School of Natural Resources, Ohio State University, Columbus 43210, USA.
Biol Reprod. 1995 May;52(5):1073-80. doi: 10.1095/biolreprod52.5.1073.
Ascorbic acid is an essential nutrient in rainbow trout diets and has been shown to play an important role in fish reproduction. Recommended dietary levels are based on immature fish, and the specific requirements for brood stock are unknown. To establish the optimum dietary level for mature rainbow trout, six graded levels of ascorbyl-2-monophosphate were fed to groups of female fish over a period of 10 mo until spawning. Increasing dietary levels of ascorbyl monophosphate resulted in significantly increased ascorbic acid concentrations in liver, kidney, ovaries, and ovulated eggs. Liver and egg concentrations were saturable at 109.3 and 266.6 micrograms ascorbic acid/g tissue, respectively. Tissue saturation levels of 83.7% and 91.2%, respectively, were reached at the highest dietary level (870 mg ascorbyl monophosphate/kg diet) tested. Both fecundity and embryo survival increased significantly with dietary ascorbyl monophosphate levels. The results indicated that the present National Research Council recommended dietary level of 50 mg ascorbic acid/kg diet for rainbow trout is inadequate for brood stock fish. An amount 8 times higher is necessary to optimize tissue ascorbic acid levels and achieve maximum reproductive success.
抗坏血酸是虹鳟鱼饲料中的一种必需营养素，已被证明在鱼类繁殖中发挥重要作用。推荐的日粮水平是基于未成熟的鱼，而亲鱼的具体需求尚不清楚。为了确定成熟虹鳟鱼的最佳日粮水平，将六个梯度水平的抗坏血酸-2-单磷酸喂给雌鱼组，持续10个月直至产卵。日粮中抗坏血酸单磷酸水平的增加导致肝脏、肾脏、卵巢和排卵卵中抗坏血酸浓度显著增加。肝脏和卵中的浓度分别在每克组织109.3微克和266.6微克抗坏血酸时达到饱和。在测试的最高日粮水平（870毫克抗坏血酸单磷酸/千克饲料）下，组织饱和水平分别达到83.7%和91.2%。繁殖力和胚胎存活率均随着日粮中抗坏血酸单磷酸水平的增加而显著提高。结果表明，目前美国国家研究委员会推荐的虹鳟鱼日粮抗坏血酸水平为50毫克/千克饲料，对亲鱼来说是不够的。需要高出8倍的量才能优化组织抗坏血酸水平并实现最大繁殖成功率。
