Sambraus F, Fjelldal P G, Remø S C, Hevrøy E M, Nilsen T O, Thorsen A, Hansen T J, Waagbø R
Institute of Marine Research (IMR), Matredal, Norway.
Department of Biology, University of Bergen, Bergen, Norway.
J Fish Dis. 2017 Sep;40(9):1195-1212. doi: 10.1111/jfd.12594. Epub 2017 Feb 11.
The aim of the present study was to investigate cataract development in diploid (2N) and triploid (3N) Atlantic salmon smolts and post-smolts at two water temperatures (10 and 16 °C) given diets with different histidine supplementation (LH, 10.4 and HH, 13.1 g kg ) before and after seawater transfer. In freshwater, a severe cataract outbreak was recorded in both ploidies reared at 16 °C. The cataract score was significantly higher in triploids compared to diploids, and the severity was lower in both ploidies fed the HH diet. The cataract development at 10 °C was minor. Low gill Na , K -ATPase activity in fish reared at 16 °C before seawater transfer was followed by osmoregulatory stress with elevated plasma electrolyte concentrations and high mortality in sea water. Both diploids and triploids reared at 10 °C developed cataracts during the seawater period, with higher severities in triploids than diploids and a reduced severity in the fish fed the HH diet. The findings of this study demonstrate the importance of environmental conditions in the husbandry of Atlantic salmon, and particularly triploids, with regard to smoltification and adjusted diets to mitigate cataract development in fresh and sea water.
本研究的目的是调查二倍体（2N）和三倍体（3N）大西洋鲑鱼苗及后鱼苗在两种水温（10和16°C）下，海水转移前后给予不同组氨酸补充量（低组氨酸，10.4；高组氨酸，13.1 g/kg）日粮时白内障的发展情况。在淡水中，记录到在16°C饲养的两个倍性群体中都爆发了严重的白内障。三倍体的白内障评分显著高于二倍体，且两种倍性群体中喂食高组氨酸日粮的鱼白内障严重程度较低。10°C时白内障的发展程度较轻。海水转移前在16°C饲养的鱼鳃钠钾ATP酶活性较低，随后出现渗透调节应激，血浆电解质浓度升高，海水养殖时死亡率较高。在10°C饲养的二倍体和三倍体在海水养殖期间都出现了白内障，三倍体的严重程度高于二倍体，喂食高组氨酸日粮的鱼严重程度降低。本研究结果表明，在大西洋鲑养殖中，特别是三倍体养殖中，环境条件对于驯化及调整日粮以减轻淡水和海水中白内障发展的重要性。
