Dataset for: Ultrasound as a non-invasive tool for monitoring reproductive physiology in female Atlantic salmon (Salmo salar)

Aiming to explore ultrasound technology as a non-invasive method for maturation monitoring, we compared ultrasound observations and measurements in female Atlantic salmon (Salmo salar) during the last year before ovulation with standard, invasive methods such as gonadosomatic index (GSI), gonad histology and sex hormone analysis. Ultrasound measurements of ovaries correlated strongly (R > 0.9, p < 0.01) with ovary weight and GSI, and could be used as a non-invasive tool for GSI estimation. Using ultrasound, we were able to identify females with advanced oocyte development and elevated sex hormone and GSI levels earlier than previously observed. Histological studies confirmed these observations showing oocyte yolk accumulation 10 months before ovulation and eight months before significant increase in sex hormones. Levels of 11-keto testosterone (11-KT) indicated a new role of this hormone at final maturation in salmon females. We propose the use of ultrasound as an alternative method to traditionally used invasive methods during sexual maturation monitoring in wild and farmed Atlantic salmon broodstock populations. Eliminating sacrifice of valuable broodfish, and reducing handling stress, would improve animal welfare in present-day broodstock management.

本研究旨在探索将超声技术作为非侵入性成熟度监测手段，对排卵前一年内的雌性大西洋鲑（Salmo salar）开展超声观测与测量，并与性腺成熟指数（gonadosomatic index, GSI）、性腺组织学及性激素分析等标准侵入性方法进行对比。卵巢超声测量值与卵巢重量及GSI呈显著强相关（R>0.9，p<0.01），可作为估算GSI的非侵入性工具。借助超声技术，我们能够比此前的观测更早地识别出卵母细胞发育晚期、性激素及GSI水平升高的雌性个体。组织学研究验证了上述观测结果：卵母细胞的卵黄积累发生于排卵前10个月，且早于性激素显著升高的时间（8个月前）。11-酮睾酮（11-keto testosterone, 11-KT）的水平提示，该激素在雌性大西洋鲑的最终成熟过程中具有新的生理功能。我们提出，在野生及养殖的大西洋鲑亲鱼种群的性成熟监测中，可采用超声技术替代传统的侵入性方法。通过避免宰杀珍贵的亲鱼并降低捕捞处理带来的应激反应，可有效改善当前亲鱼管理中的动物福利水平。