Ontogenetic Dietary Changes and Thiamine Status of Lake Ontario Chinook Salmon, 2005-2006
Ontogenetic Dietary Changes and Thiamine Status of Lake Ontario Chinook Salmon, 2005-2006
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DOI：
10.1002/nafm.10659
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发表时间：
2021-08-30
影响因子：
1.1
通讯作者：
Rush, Scott
中科院分区：
文献类型：
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作者：
Fitzsimons, John D.;Honeyfield, Dale C.;Rush, Scott
在五大湖，据报道，由于高硫胺酶活性，Alewife Alosa pseudoharengus饮食导致鲑鱼硫胺素缺乏症。硫胺素缺乏症的个体发育及其与Alewife消费的关系尚未确定在该系统内的奇努克鲑鱼Oncorhynchus tshawytscha。使用稳定的同位素混合模型沿着与肌肉硫胺素，我们评估个体发育的变化，饮食和相应的肌肉硫胺素状态的安大略湖奇努克鲑鱼TL范围从100至1,000毫米。硫胺素水平最高的年轻的一年中收集的支流安大略湖，但下降一旦奇努克鲑鱼进入安大略湖。在安大略湖，青少年（200-400毫米; 97-99%）和成年人（>400毫米; 97-100%）奇努克鲑鱼的饮食几乎完全由Alewives使用混合模型估计。这种Alewife饮食与奇努克鲑鱼肌肉硫胺素的个体发育下降有关。硫胺素浓度随着肌肉大小的增加而逐渐下降，在720-758 pmol/g肌肉处达到稳定。低于硫胺素阈值500 pmol/g（与平衡丧失相关）的个体比例随着TL增加至799 mm，然后在800和1，000 mm之间下降。在这些肌肉浓度下，没有观察到硫胺素缺乏的外在迹象。计算硫胺素的身体储存的总质量积累（肌肉浓度乘以体重）显示出意外的和显着的增加与大小。虽然看来，饮食Alewives影响硫胺素的状态，有不确定的因素，如不完全破坏硫胺素的硫胺素酶，肠道合成的硫胺素，鳃吸收水硫胺素，和/或其他因素，这有助于这些奇努克鲑鱼的整体硫胺素状态。
In the Great Lakes, an Alewife Alosa pseudoharengus diet has been reported to cause thiamine deficiency in salmonines as a result of high thiaminase activity. The ontogeny of thiamine deficiency and its relationship to Alewife consumption have not been determined in Chinook Salmon Oncorhynchus tshawytscha within this system. Using stable isotope mixing models along with muscle thiamine, we assessed ontogenetic changes in the diet and corresponding muscle thiamine status of Lake Ontario Chinook Salmon ranging in TL from 100 to 1,000 mm. Thiamine levels were highest in young of the year collected in a tributary of Lake Ontario but declined once Chinook Salmon entered Lake Ontario. In Lake Ontario, the diets of juvenile (200-400 mm; 97-99%) and adult (>400 mm; 97-100%) Chinook Salmon consisted almost entirely of Alewives as estimated using mixing models. This Alewife diet was associated with an ontogenetic decline in muscle thiamine among Chinook Salmon. The asymptotic decline in thiamine concentration with increasing size plateaued at 720-758 pmol/g of muscle. The proportion of individuals below a thiamine threshold of 500 pmol/g (associated with a loss of equilibrium) increased with TL up to 799 mm and then declined between 800 and 1,000 mm. At these muscle concentrations, no outward signs of thiamine deficiency were observed. Calculation of total mass accumulation of body stores of thiamine (muscle concentration times body weight) showed an unexpected and significant increase with size. Although it appears that dietary Alewives affected thiamine status, there were undetermined factors, such as incomplete destruction of thiamine by thiaminase, gut synthesis of thiamine, gill absorption of water thiamine, and/or other factors, that contributed to the overall thiamine status of these Chinook Salmon.