in order to determine the changes in serum and blood factors of rainbow trout following experimental infection with a pathogenic aeromonas hydrophila, the cause of haemorrhagic septicemia in fish, three groups of rainbow trout (10 fish in each group) were injected intraperitoneally with 105, 106 and 107 of this bacteria respectively. the same number of fish in a control group were injected simi...

Skin removal is a generally accepted method to reduce exposure to contaminants through fish consumption. However, inconsistent results from studies on the effectiveness of this method suggest influence of other factors such as characteristics of contaminants and fish species. This study investigated the effects of skin removal on the lipid contents and concentrations of total mercury, α-chlorda...

—In response to a petition to list Great Basin redband trout (subspecies of rainbow trout Oncorhynchus mykiss) as threatened or endangered, the U.S. Fish and Wildlife Service conducted a status review in 1998. To support that review, we conducted a survey of the abundances of redband trout in each of six subbasins of the Great Basin that included the states of Oregon, California, and Nevada. We...

Philip Lymbery is an international animal welfare consultant. In 1992, his report, The Welfare of Farmed Fish, was the UK's first to look at the welfare issues in salmon and trout farming. This was written whilst working for Compassion In World Farming (1990-2000), where he spent the last 7 years as Campaigns Director. Maintaining a special interest in fish welfare, Philip submitted both writte...

Accurate assessment of species identity is fundamental for conservation biology. Using molecular markers from the mitochondrial and nuclear genomes, we discovered that many putatively native populations of greenback cutthroat trout (Oncorhynchus clarkii stomias) comprised another subspecies of cutthroat trout, Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus). The error can be e...

A Streptococcus species biochemically and serologically identical to the rainbow trout pathogenic Streptococcus species was isolated from the internal organs of the fish specific leech, Batracobdelloides tricarinata. These leeches were obtained from Roodeplaat Dam, near Pretoria, in which rainbow trout do not occur. This is the first isolation of this bacterium from an environmental source not ...

Fish fauna of small coldwater streams of North America typically include trout and salmon, sculpins, minnow, sticklebacks, suckers, or lampreys (Hocutt and Wiley 1986). Standard sampling protocols provided herein apply primarily for trout and salmon because of their sport and commercial values (Johnson et al. 2007). As interest in nonsalmonid species grows, further development of sampling metho...

background & aim: continuous use of antibiotics leads to drug resistance and thereby to a reduced efficacy of the drugs. antibiotics accumulate in the environment and fish pose a potential risk to consumers and to the environment.increased public awareness of the negative effects caused by overexposure to synthetic chemicals has led to the search for ‘‘green drugs’’, such as organic and syn...

We describe 12 diagnostic single nucleotide polymorphism (SNP) assays for use in species identification among rainbow and cutthroat trout: five of these loci have alleles unique to rainbow trout (Oncorhynchus mykiss), three unique to westslope cutthroat trout (O. clarkii lewisi) and four unique to Yellowstone cutthroat trout (O. clarkii bouvieri). These diagnostic assays were identified using a...

—There is evidence that actively moving salmonids are of lower condition than the general population, and they are sometimes regarded as inferior to resident fish. However, little information exists on the permanence of this attribute. We used mark–recapture and two-way traps to determine whether there are differences in the condition and growth of mobile and resident Bonneville cutthroat trout...