Subclinical Listonella anguillarum infection does not impair recovery of swimming performance in rainbow trout Oncorhynchus mykiss.
This study examines whether injections of the commonly used bacterial-challenge pathogen Listonella anguillarum (formerly Vibrio anguillarum) negatively impact the ability of rainbow trout Oncorhynchus mykiss Walbaum to perform repeat swimming trials. Fish were given intraperitoneal injections of either a sub-lethal (10(5) colony forming units; CFUs) or a lethal (10(7) CFUs) dose of L. anguillarum, held for 48 h, and then given 2 successive ramp critical swimming speed (Ucrit) tests separated by 45 min. Compared with saline-injected control fish, the low-dose injection did not significantly impair swimming performance and recovery. Similarly, Ucrit and re-performance for fish surviving the high-dose injection were comparable to control (2 of 6 fish died after injection and before testing). In contrast, a positive control test of seawater challenge did impair recovery of swimming performance. In view of these results and common use of L. anguillarum as a challenge pathogen for toxicological studies, it seems unlikely that the consequences of pathogenesis impact the important cardiorespiratory changes associated with exercise.
Tierney
Keith B
KB
Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada. ktierney@sfu.ca
Balfry
Shannon K
SK
Farrell
Anthony P
AP
D000704:Analysis of Variance; D000818:Animals; D005069:Evaluation Studies as Topic; D005393:Fish Diseases / Q000382:microbiology* / Q000503:physiopathology*; D016905:Gram-Negative Bacterial Infections / Q000503:physiopathology / Q000662:veterinary*; D017686:Oncorhynchus mykiss; D013550:Swimming / Q000502:physiology*; D014737:Vibrionaceae