Open AccessFeeding Ration, Genetics, and Reproductive Traits in Female Coho Salmon: Is Bigger Better?
Author(s) -
Myers James M.,
Park Linda K.,
Neely Kathleen G.,
Swanson Penny,
Elz Anna E.,
Hard Jeffrey J.
Publication year - 2011
Publication title -
journal of the world aquaculture society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.655
H-Index - 60
eISSN - 1749-7345
pISSN - 0893-8849
DOI - 10.1111/j.1749-7345.2011.00520.x
Subject(s) - biology , fecundity , zoology , body weight , reproduction , oncorhynchus , fish <actinopterygii> , ecology , endocrinology , fishery , demography , population , sociology
We assessed the effects of different feeding regimes on reproductive traits in coho salmon, Oncorhynchus kisutch . Ration treatments subjected fish to different energy levels during oocyte proliferation (Year 1) and oocyte maturation (Year 2). Fish from 10 full‐sibling families were fed at either the recommended feeding rate or double the recommended ration during the first year. At the beginning of the second year, each ration group was split again into recommended and double ration tanks for a total of four dietary treatments. At the end of the second year, 365 females from the four treatment groups were spawned and body weight, egg weight, and egg number were measured. Overall, the fish fed the double ration during both years grew the fastest (50.1% larger than controls), had the highest egg number (46.3% larger), and had the largest eggs (9.6% larger), although similar increases were observed feeding at the double ration level during the second year alone. Ration modification produced significant changes in some reproductive traits, especially egg number, while family effects had a greater influence on relative fecundity (eggs/g female body weight) and egg weight. In fact, family effects were significant for all of the traits. Results indicate that reproductive traits can be manipulated through changes in ration and/or via genetic selection, either directly or indirectly.