STUDIES ON CAROTENOID TRANSPORT IN RED-AND WHITE-FLESHED CHINOOK SALMON (ONCORHYNCHUS TSHAWYTSCHA)

奇努克鲑鱼在太平洋鲑鱼（Oncorhynchus spp.）中是独一无二的，因为在海上喂养的未成熟鱼类会发育出两种不同的肌肉颜色之一，并且被称为红肉和白肉的奇努克鲑鱼。这些颜色类型受到强烈的遗传控制。像其他太平洋鲑鱼一样，红肉的奇努克鲑鱼更为常见，由于类胡萝卜素的沉积，它们的肌肉颜色从粉红色到深红色不等。白肉鱼显然不会在肌肉中沉积类胡萝卜素。红肉和白肉大马哈鱼的肌肉类胡萝卜素水平经常以两种颜色类型为指导进行检查，但很少有报道描述类胡萝卜素在肌肉以外的各种组织中的分布。研究了红肉和白肉奇努克鲑鱼的肌肉、卵巢、被皮和血清中类catotena的分布及其肌肉近似成分。除了类胡萝卜素水平外，红肉和白肉鲑鱼的肌肉水分、蛋白质和脂肪成分没有显著差异。在红肉和白肉大马哈鱼的卵巢中发现了相似的类胡萝卜素水平，尽管白肉大马哈鱼的肌肉类胡萝卜素水平明显低于红肉大马哈鱼。这表明白肉大马哈鱼有能力在卵巢中积累类胡萝卜素，而不是在肌肉中。白肉大马哈鱼的肌肉中可能缺乏类胡萝卜素受体，这似乎是它们无法在肌肉中积累类胡萝卜素的原因。

Chinook salmon are unique among Pacific salmon (Oncorhynchus spp.) because immature fish feeding at sea develop one of two distinct muscle colors, and are known as red- and white-fleshed chinook. These color types are under strong genetic control. The red-fleshed chinook salmon, like the other Pacific salmon, are more common, their muscle color ranging from pink to deep red due to the deposition of carotenoids. The white-fleshed ones apparently do not deposit carotenoids in their muscle. The muscle carotenoid levels of red- and white-fleshed chinook salmon are frequently examined with the guidance of the two color types, but there are very few reports describing the carotenoid distribution in various tissues other than muscle.Catotenoid distribution was examined in muscle, ovary, integument, and serum from red- and white-fleshed chinook salmon along with their muscle proximate compositions. There were no significant differences in muscle compositions of moisture, protein, and lipid except for the carotenoid levels between red- and white-fleshed salmon. Similar carotenoid levels of ovaries were found between red- and white-fleshed chinook salmon, although the muscle carotenoid level of white-fleshed salmon was apparently low compared to redfleshed salmon. This suggests that white-fleshed chinook salmon have the ability to accumulate the carotenoids in their ovaries but not muscle. The white-fleshed chinook salmon may be devoid of carotenoid receptors in their muscle and this seems to be the reason for the failure to accumulate the carotenoids in their muscle.