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Full-Text Articles in Aquaculture and Fisheries
The Effects Of Crossbreeding And Low Fish Meal Diets On Growth-Related Traits In Chinook Salmon (Oncorhynchus Tshawytscha), Katarina H. Doughty
The Effects Of Crossbreeding And Low Fish Meal Diets On Growth-Related Traits In Chinook Salmon (Oncorhynchus Tshawytscha), Katarina H. Doughty
Electronic Thesis and Dissertation Repository
Growth rate is the most important trait that can be manipulated to create more efficient aquaculture. Crossbreeding, where different populations are bred, has the potential to increase performance through release from inbreeding depression. I crossed a farm population of Chinook salmon (Oncorhynchus tshawytscha) with seven wild populations, then compared growth rate, feed conversion efficiency, swimming speed and metabolic rate between the crossbred and original farmed lines. Crossbreeding resulted in increased growth rates, but had no effect on the other traits. I next evaluated the feasibility of using a diet that replaced fish meal with corn gluten meal and …
Fish Out Of Salt Water: Smoltification In Subyearling Chinook Salmon From The Laurentian Great Lakes, Steve Sharron
Fish Out Of Salt Water: Smoltification In Subyearling Chinook Salmon From The Laurentian Great Lakes, Steve Sharron
Electronic Thesis and Dissertation Repository
The timing of smoltification in juvenile anadromous salmonids is important to ensure individuals match their preparedness with their migration timing and the optimal conditions in the environment. I performed the first study of smoltification in adfluvial juvenile Chinook salmon naturalized in the Laurentian Great Lakes. In a hatchery study, I found that juveniles from one of these populations have similar patterns of smoltification timing to individuals from anadromous populations. Their Na+/K+ ATPase activity, a common indicator or smolt status, peaked at 7.7 μmoles ADP/mg protein/hour on July 1 in freshwater. During the peak period, individual body size …
Introduced Chinook Salmon (Oncorhynchus Tshawytscha) In Lake Huron: Do They Spawn At The Right Time?, Meghan T. Gerson
Introduced Chinook Salmon (Oncorhynchus Tshawytscha) In Lake Huron: Do They Spawn At The Right Time?, Meghan T. Gerson
Electronic Thesis and Dissertation Repository
Chinook salmon (Oncorhynchus tshawytscha), following their introduction to the Great Lakes, have successfully colonized many tributaries. Under the hypothesis that colonization success is facilitated by intrinsic factors (i.e., preadaptation), I predicted that patterns of reproductive timing in an introduced population would show similarities with those in their native range. To test this prediction, attributes of reproductive timing were characterized in Chinook salmon from the Sydenham River, Ontario. In their native range, female Chinook salmon exhibit a seasonal decline in reproductive lifespan, a decline in fat stores, low egg retention at death (< 0.5%), and spawning at temperatures below 12.8°C. In contrast, Sydenham River Chinook salmon showed no seasonal decline in reproductive lifespan or fat stores and nineteen of twenty females had egg retention greater or equal to 0.5%. Also, many individuals (30%) spawned when water temperatures exceeded 12.8°C. Thus, individuals do not appear to be pre-adapted in this system.