Thermal Tempering Does Not Increase the Survival of Eyed Salmonid Eggs

• 作者: Lynn Slama Nathan Huysman Jill M. Voorhees Michael E. Barnes
• 来源期刊: 应用科学(英文)
• 学科: 工学
• 关键词: TEMPERING TROUT EGGS SALMONID Iodophor
• 年，卷（期）: 2021,（3）
• 页码范围: 287-293
• 页数: 7页
• 分类号: TG1

摘要

Eyed salmonid eggs can be subjected to large temperature swings during development, particularly when shipped in ice-filled containers from broodstock facilities to production hatcheries. This study examined the effect of thermal tempering on the survival of brown trout <em>Salmo trutta</em> and rainbow trout <em>Oncorhynchus mykiss</em> eyed eggs to hatch. Eyed eggs at 1<span style="white-space:nowrap;">°</span>C were either directly placed in 11<span style="white-space:nowrap;">°</span>C water or allowed to thermally temper from 1<span style="white-space:nowrap;">°</span>C to 11<span style="white-space:nowrap;">°</span>C gradually over an hour. In addition, each of the tempering treatments occurred either with or without a 10-minute iodophor disinfection treatment. Tempering had no significant effect on survival-to-hatch in either species (85% - 97%). However, survival was significantly lower in rainbow trout eggs subjected to iodine disinfection (73% - 75%) compared to non-disinfected eggs (91% - 97%), likely because of the close proximity to hatch. The results of this study indicate that slowly raising the temperature (thermal tempering) of brown trout and rainbow trout eyed eggs is unnecessary. Additionally, iodine disinfection of eyed salmonid eggs in close proximity to hatching should be avoided.