Survival of Whirling-Disease-Resistant Rainbow Trout Fry in the Wild: A Comparison of Two Strains

Abstract.—Laboratory challenges of two rainbow trout Oncorhynchus mykiss strains with Myxobolus cerebralis triactinomyxons confirm the resistance to whirling disease of the Hofer trout strain. Although the number of fish that became infected and developed clinical disease was similar for the Hofer and the Trout Lodge strains at all challenge doses, the median spore numbers were lower at all challenge doses for the Hofer rainbow trout. Parasite challenge doses required to produce lesions of high severity were 10-fold lower for the Trout Lodge strain (100 triactinomyxons) than the Hofer strain (1,000 triactinomyxons). Challenges of the Hofer strain with other common salmonid pathogens; the myxozoans Ceratomyxa shasta and Tetracapsuloides bryosalmonae, the bacterium Yersinia ruckeri, and the viruses Salmonid herpes-like virus type 1 and infectious hematopoietic necrosis virus demonstrate that the susceptibility of the Hofer strain was similar to what would be expected for other strains of rainbow trout, either domestic or wild. These pathogen challenges provide evidence that the Hofer trout present a low risk for introducing any pathogen that might be detrimental to native or established fish populations or further amplifying those that are endemic.

Download Full-text

Kinetics of local and systemic immune cell responses in whirling disease infection and resistance in rainbow trout

Parasites & Vectors ◽

10.1186/s13071-019-3505-9 ◽

2019 ◽

Vol 12 (1) ◽

Cited By ~ 2

Author(s):

Mona Saleh ◽

Ruth Montero ◽

Gokhlesh Kumar ◽

Arun Sudhagar ◽

Adina Friedl ◽

...

Keyword(s):

Rainbow Trout ◽

Immune Cell ◽

Whirling Disease ◽

Cell Responses ◽

Kinetics Of

Download Full-text

Relative quantification of immune-regulatory genes in two rainbow trout strains, Oncorhynchus mykiss, after exposure to Myxobolus cerebralis, the causative agent of whirling disease

Parasitology Research ◽

10.1007/s00436-007-0582-z ◽

2007 ◽

Vol 101 (4) ◽

pp. 1019-1027 ◽

Cited By ~ 21

Author(s):

Vanessa I. C. Severin ◽

Mansour El-Matbouli

Keyword(s):

Rainbow Trout ◽

Oncorhynchus Mykiss ◽

Causative Agent ◽

Regulatory Genes ◽

Relative Quantification ◽

Whirling Disease ◽

Myxobolus Cerebralis

Download Full-text

Myxosoma cerebralis: Inactivation of Spores by Hot Smoking of Infected Trout

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f82-124 ◽

1982 ◽

Vol 39 (6) ◽

pp. 926-928 ◽

Cited By ~ 6

Author(s):

Ken Wolf ◽

Maria E. Markiw

Keyword(s):

Rainbow Trout ◽

Aquatic Environment ◽

Brook Trout ◽

Salvelinus Fontinalis ◽

Soil Samples ◽

Healthy Tissue ◽

Salmo Gairdneri ◽

Heat Inactivation ◽

Whirling Disease

We processed 2-yr-old rainbow trout (Salmo gairdneri) and brook trout (Salvelinus fontinalis) with clinical whirling disease, which is caused by Myxosoma cerebralis, in one of the following ways: iced, iced and brined, or iced, brined, and hot smoked at 66 °C for 40 min. Skeletal elements of each group were added to tanks containing soil samples from an aquatic environment free of M. cerebralis and aged for 4 mo at 12.5 °C. Following this we assayed for infectivity by holding susceptible rainbow trout fry for 3 mo in the tanks of aquatic soil and skeletal elements. The fry were then examined for M. cerebralis spores. Spores were found in the fry from tanks that had received iced and iced and brined samples, but not in fry from the tanks containing hot smoked tissue, healthy tissue, or no tissue — the last two being negative controls.Key words: whirling disease, Myxosoma cerebralis, heat inactivation, hot smoking

Download Full-text

Survival of Hatchery-Reared Rainbow Trout (Salmo gairdneri) in Relation to Stamina Tunnel Ratings

Journal of the Fisheries Research Board of Canada ◽

10.1139/f72-145 ◽

1972 ◽

Vol 29 (7) ◽

pp. 1005-1009 ◽

Cited By ~ 5

Author(s):

Donald L. Horak

Keyword(s):

Rainbow Trout ◽

Conclusive Evidence ◽

Salmo Gairdneri ◽

Swimming Ability ◽

In The Wild ◽

Lotic Environments ◽

Survival Potential

No conclusive evidence was found in tests from 1966 to 1969 in either lentic or lotic environments to support the hypothesis that hatchery-reared rainbow trout (Salmo gairdneri) with a high-stamina index had a higher survival potential than those whose stamina index was low. Physical stamina was measured by determining the length of time each fish could withstand sustained swimming in a specially constructed stamina tunnel. For high-stamina rating, fish swam in the tunnel for 80 min; for low stamina, 1–10 min.In tests of reproducibility of stamina ratings, improved swimming ability of low-stamina fish was demonstrated upon retesting in the tunnel. In 1970, with retested fish, still no evidence was found to indicate higher survival of fish rated as high in stamina. Additional studies are needed to determine if performance of hatchery-reared salmonids in a stamina tunnel is a valid indicator of their survival potential in the wild.

Download Full-text