Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Pau, France.
INRAE, Universite de Pau et des Pays de l'Adour, E2S UPPA, Numea, 64310, Saint-Pée-sur-Nivelle, France.
Chemosphere. 2024 Sep;364:142967. doi: 10.1016/j.chemosphere.2024.142967. Epub 2024 Jul 27.
The increasing use of alternative feeds for sustainable aquaculture leads to a reduced selenium content requiring the use of supplements to maintain the antioxidant status of farmed fish. The introduction of tuna by-products in fish feed is attractive for their selenium content, but the presence of mercury limits their use as it may negatively impact fish health. Indeed, selenium and mercury metabolism, in relation to their interaction and biological effects in fish, is far from being fully understood. This study aims to assess the impact of parental and dietary supplementation with selenomethionine and methylmercury on selenium and mercury localisation and concentrations in tissues of 3-week rainbow trout fry. Six diets were used. Broodstock were fed a plant-based diet Bpc (with 0.2 μg g selenium and 0 μg g mercury) or a tuna by-product-based diet Bt (with 4 μg g selenium and basal mercury at 0.2 μg g) during 6 months, supplemented or not with 4 μg g of selenomethionine for the plant-based diet Bpo and/or with 2 μg g of methylmercury for diets Bph, Bpho and Bth. Their offspring were fed the plant-based diet Fpc, supplemented or not with the same levels of selenomethionine and methylmercury, until their third week. Mercury and selenium concentrations were determined in fry whole-body by ICP MS and quantitative images of selenium and mercury were produced by LA-ICP MS from fry whole-body thin sections. Dietary supplementation of fry with selenium and/or mercury increased their concentration in all tissues, especially in liver, kidney, muscle and intestine. Parental selenomethionine supplementation had a more pronounced effect on fry selenium levels than tuna by-products diet. Mercury transfer from broodstock to their offspring was weak. Mercury concentrations decreased in the kidney of fry supplemented with both selenium and mercury, which could be related to the presence of selenium.
替代饲料在可持续水产养殖中的应用日益增加，导致硒含量降低，需要使用补充剂来维持养殖鱼类的抗氧化状态。在鱼饲料中引入金枪鱼副产品因其硒含量而具有吸引力，但由于汞的存在限制了其使用，因为它可能对鱼类健康产生负面影响。事实上，硒和汞的代谢，以及它们在鱼类中的相互作用和生物效应，远未被完全理解。本研究旨在评估亲代和饮食补充硒蛋氨酸和甲基汞对 3 周龄虹鳟鱼苗组织中硒和汞定位和浓度的影响。使用了六种饮食。亲鱼在 6 个月内分别喂食植物性饮食 Bpc（含 0.2μg g 硒和 0μg g 汞）或金枪鱼副产品为基础的饮食 Bt（含 4μg g 硒和基础汞为 0.2μg g），补充或不补充 4μg g 植物性饮食的硒蛋氨酸和/或补充 2μg g 甲基汞饮食 Bph、Bpho 和 Bth。它们的后代喂食植物性饮食 Fpc，并补充或不补充相同水平的硒蛋氨酸和甲基汞，直到它们的第三周。通过 ICP-MS 测定鱼苗全身体内的汞和硒浓度，并通过 LA-ICP-MS 从鱼苗全身体薄片中生成硒和汞的定量图像。鱼苗饮食补充硒和/或汞会增加其在所有组织中的浓度，特别是在肝脏、肾脏、肌肉和肠道中。亲代硒蛋氨酸补充对鱼苗硒水平的影响比金枪鱼副产品饮食更为显著。亲代向后代传递汞的能力较弱。补充硒和汞的鱼苗肾脏中汞浓度降低，这可能与硒的存在有关。
