Swimming performance and associated ionic disturbance of juvenile pink salmon Oncorhynchus gorbuscha determined using different acceleration profiles.
Swimming performance was assessed in juvenile pink salmon Oncorhynchus gorbuscha (body mass<5.0 g) using five different protocols: four constant acceleration tests each with a different acceleration profile (rates of 0.005, 0.011, 0.021 and 0.053 cm s(-2)) and a repeated ramped-critical swimming speed test. Regardless of the swim protocol, the final swimming speeds did not differ significantly (P>0.05) among swim tests and ranged from 4.54 to 5.20 body lengths s(-1). This result supports the hypothesis that at an early life stage, O. gorbuscha display the same fatigue speeds independent of the swimming test utilized. Whole body and plasma [Na+] and [Cl-] measured at the conclusion of these tests were significantly elevated when compared with control values (P<0.05) and appear to be predominantly associated with dehydration rather than net ion gain. Given this finding for a small salmonid, estimates of swim performance can be accurately measured with acceleration tests lasting<10 min, allowing a more rapid processing than is possible with a longer critical swim speed test.
Nendick
L
L
Department of Zoology, University of British Columbia, 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada. nendickl@interchange.ubc.ca
Grant
A
A
Gardner
M
M
Sackville
M
M
Brauner
C J
CJ
Farrell
A P
AP
D000054:Acceleration; D000704:Analysis of Variance; D000818:Animals; D049628:Body Size / Q000502:physiology; D001834:Body Water / Q000502:physiology; D002712:Chlorides / Q000378:metabolism*; D005221:Fatigue / Q000097:blood / Q000503:physiopathology; D012474:Salmon / Q000502:physiology*; D012964:Sodium / Q000378:metabolism*; D013550:Swimming / Q000502:physiology*
D002712:Chlorides; D012964:Sodium