Endocrine Control of Salmonid Development and Seawater Adaption

This project seeks to reduce losses of fish due to improper timing of release from hatcheries by developing an accurate physiological assessment of salmon development and the endocrine mechanisms responsible for this development. Heretofore the general period for hatchery release has been decided according to the regular (Gregorian) calendar, and based on insufficient biological information. As a consequence, the actual date of hatchery release or transport for subsequent release was determined by river conditions (which in part corresponded to water releases from dams), transport facilities, hatchery logistics, and other special considerations having little to do with factors determining ultimate contribution to the salmon fishery. We plan to investigate the relation between the lunar cycle-based thyroxin surge and the several components of smoltification and to establish a reliable endocrinology of development and seawater adaptation by continuing our analysis of a variety of endocrine mechanisms.

本项目旨在通过构建精准的鲑鱼发育生理评估体系、解析调控该发育过程的内分泌机制，降低因孵化场放流时机不当造成的鱼类损失。迄今为止，孵化场放流的通用时段一直依据常规公历（Gregorian calendar）确定，且所依托的生物学信息较为匮乏。因此，孵化场放流或转运后再放流的实际日期，往往由河流水文条件（部分对应大坝泄水调度）、运输设施、孵化场后勤及其他特殊因素决定，而这些因素几乎与决定鲑鱼渔业最终贡献的核心要素无关。本项目拟研究基于月周期的甲状腺素（thyroxin）激增与幼鲑降海变态（smoltification）各环节间的关联，并通过持续分析多种内分泌调控机制，构建一套可靠的发育与海水适应内分泌学评估体系。