Background: Much has been written about introduced rainbow trout (Oncorhynchus mykiss) interbreeding and outcompeting cutthroat trout (Oncorhynchus clarkii). However, the specific mechanisms by which rainbow trout and their hybrids outcompete cutthroat trout have not been thoroughly explored, and the published data is limited to lotic ecosystems. Materials and Methods: Samples of rainbow trout ...

BACKGROUND Despite vaccination with a commercial vaccine with a documented protective effect against Vibrio anguillarum O1 disease outbreaks caused by this bacterium have been registered among rainbow trout at Danish fish farms. The present study examined specific serum antibody levels as a valid marker for assessing vaccination status in a fish population. For this purpose a highly sensitive e...

Propolis, a resinous substance collected by Apis mellifera bees from various plant sources is transformed in the presence of bee enzymes. Short- and long-term effects of diet supplementation with ethanol extract of Iranian propolis (EEIP) was investigated on growth and immunity in juvenile rainbow trout. The fish (mean body weight 30 ± 3.2 g) were fed a commercial diet supplemented with 0 (cont...

Rainbow trout are classified as Oncorhynchus mykiss, and as such belong to the same genus as Pacific salmon, and to the family Salmonidae, which includes Atlantic salmon (Salmo salar), various trout (Salvelinus sp.), Arctic char (Salvelinus alpinus), Arctic grayling (Thymallus arcticus) and whitefish (Coregonus sp.). Rainbow trout are native to areas around the North Pacific Ocean, from souther...

The direct predatory effects of introduced rainbow trout Oncorhynchus mykiss on native longnose dace Rhinichthys cataractae were examined using a series of in-stream enclosures to determine if presence, density, or acclimation period of rainbow trout influenced survival of longnose dace. The number of longnose dace remaining in enclosures over the first 72 hours after rainbow trout introduction...

A study was undertaken to compare the virulence and serum killing resistance properties of Atlantic salmon and rainbow trout Yersinia ruckeri isolates. Five isolates, covering heat-stable O-antigen O1, O2 and O5 serotypes, were tested for virulence towards fry and juveniles of both species by experimental bath challenge. The sensitivity of 15 diverse isolates to non-immune salmon and rainbow tr...

The direct predatory effects of introduced rainbow trout Oncorhynchus mykiss on native longnose dace Rhinichthys cataractae were examined using a series of in-stream enclosures to determine if presence, density, or acclimation period of rainbow trout influenced survival of longnose dace. The number of longnose dace remaining in enclosures over the first 72 hours after rainbow trout introduction...

Ž . Rainbow trout Oncorhynchus mykiss of initial average weight 150 g and brook trout Ž . SalÕelinus fontinalis initially weighing 124 g on average, were reared at different growth rates Ž . Ž . by feeding either a high H, close to satiation or low L, half of H ration of a commercial diet. Fish were reared for 6 to 15 weeks in order to reach same size class. Fast growth increased whole Ž . Ž . ...

of the wildlife resources and a producer of additional fish and game via hatcheries and habitat management. Sometimes these roles of commodity versus stewardship are at odds. Such is the case where the DWR stocks exotic species such as rainbow trout to provide recreational fishing while attempting to conserve populations of native species such as the cutthroat trout. Cutthroat are the only trou...

The susceptibility of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) to the monogenean Discocotyle sagittata in the United Kingdom was assessed by experimental infection of naive fish. One month postinfection with 100 oncomiracidia/host, brown trout harbored significantly lower burdens (27.7 worms/host +/- 4.13 SE) than rainbow trout (47.8 worms/host +/- 3.90; P = 0.002). Th...