|Document Type:||Journal Article|
|Title:||A comparison of early development between a domesticated strain of coho salmon (Oncorhynchus kisutch) and its parental stock|
|Author:||Kathleen Guinevere Neely, James M. Myers, Jeffrey J. Hard|
|Journal:||Transactions of the American Fisheries Society|
We compared the rate of early development and yolk conversion efficiency in a domesticated stock of coho salmon Oncorhynchus kisutch that had been selected for improved growth to pan size (350 g) over 18 generations with that of its hatchery-origin unselected parental stock. Fish from both the domesticated stock and the parental stock were spawned and incubated under similar conditions. The domesticated fish produced significantly smaller eggs, reached blastopore closure sooner, and utilized their yolk store more efficiently than the parental stock. Because we were concerned that egg size may have confounded the results of the blastopore closure portion of the experiment,we repeated the experiment using eggs of sizes different from those of the domesticated stock. We determined that the rate of early embryonic development to blastopore closure was strongly influenced by egg size, an influence that probably confounded our stock comparison. In contrast, comparisons of later embryonic growth rates show a clear distinction between the domesticated stock and parental stock, the domesticated stock exhibiting a growth rate significantly faster than that of parental stock for exogenous feeding.