Abstract
Juvenile landlocked Chinook salmon (Oncorhynchus tshawytscha) (mean ± SD initial weight 2.6 ± 0.7 g, fork length 6.3 ± 0.5) were reared in three different water velocities [0.5, 1.5 and 3.0 body length/s (BL/s)] for four weeks to determine possible effects of water velocity on growth, condition, and survival. Fish were sampled for weight, fork length, condition factor, hepatosomatic index (HSI), viscerosomatic index (VSI), and fin erosion after four weeks of feeding to satiation. At the end of the feeding trial, the fish were handled and transported to simulate stocking, with survival observed over the following 10 d. Following four weeks of feeding, fish reared in 0.5 and 1.5 BL/s had the same growth and food conversion ratio, but fish reared at 3.0 BL/s had a significant reduction in both metrics. Furthermore, fish reared at 1.5 BL/s had a significantly higher condition factor than fish reared in other treatments. No significant differences were found for HSI, VSI, fin erosion, or survival. The results from this study indicate that a moderate velocity (1.5 BL/s), which is necessary for circular tanks to be self-cleaning, is not detrimental to fish growth or condition, but a faster water velocity (3.0 BL/s) negatively affects fish growth and food utilization.
Highlights
Using rearing velocities to exercise cultured fish has been shown to influence fish growth [1]-[3] and food conversion [4] [5]
The negative impacts on growth and food conversion ratios (FCR) associated with the 3.0 body length/s (BL/s) swimming speed likely indicates an increased energetic cost compared to the two lesser velocities
1.5 BL/s which is required for tanks to sufficiently be self-cleaning did not result in any reduction in growth or FCR in comparison to fish in the 0.5 BL/s
Summary
Using rearing velocities to exercise cultured fish has been shown to influence fish growth [1]-[3] and food conversion [4] [5]. (2014) Rearing Velocity Impacts on Landlocked Fall Chinook Salmon (Oncorhynchus tshawytscha) Growth, Condition, and Survival. The effect of exercise on Chinook salmon (Oncorhynchus tshawytscha) led to reduced growth. Kiessling et al [6] showed that Chinook salmon swimming at speeds of 0.5 - 1.5 BL/s for 212 days had the same growth rate, but higher swimming speeds resulted in increased feed consumption and decreased food conversion ratios (FCR). Decreased growth performance of Chinook salmon reared at higher water velocities may be compensated by increased fish quality [4] [7] and increased post-stocking survival [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
