Accumulation of zinc by rainbow trout as influenced by pH, water hardness and fish size

The diets and growth rates of rainbow trout in the Wollomombi and Guy Fawkes Rivers in northern New South Wales were examined. The growth rate of trout in the Wollomombi River was much higher than that of fish in the Guy Fawkes River. Spearman rank correlation coefficients indicated that stream type was more important than fish size in determining the composition of the diet of the trout. Benthic invertebrates formed the largest component of the diet in both streams: 66.0 and 63.0% of ash-free dry weight (AFDW) in the Wollomombi River and the Guy Fawkes River, respectively. Trout in the Wollomombi River consumed more nektonic prey (33.3% of AFDW) than fish in the Guy Fawkes River (3.7% of AFDW). In contrast, surface food (aquatic imagines and terrestrial insects) made up a much higher proportion of the diet of trout in the Guy Fawkes River (33.9% of AFDW) than in the Wollomombi River (0.6% of AFDW). Crayfish were a major component of the diet (in terms of AFDW) in both streams, their proportions increasing with fish size. The significance of crayfish in relation to fish growth is discussed.

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Toxicity of TFM (Lampricide) to Six Early Life Stages of Rainbow Trout (Salmo gairdneri)

Journal of the Fisheries Research Board of Canada ◽

10.1139/f73-176 ◽

1973 ◽

Vol 30 (8) ◽

pp. 1047-1052 ◽

Cited By ~ 6

Author(s):

L. E. Olson ◽

L. L. Marking

Keyword(s):

Rainbow Trout ◽

Early Life ◽

Natural Waters ◽

Life Stage ◽

Water Hardness ◽

Salmo Gairdneri ◽

Life Stages ◽

Early Life Stages ◽

Margin Of Safety ◽

Coexisting Species

The lampricide TFM (3-trifluoromethyl-4-nitrophenol) was tested against the following life stages of rainbow trout (Salmo gairdneri): green eggs, eyed eggs, sac fry, swim-up fry, fry, and fingerlings in four water hardnesses (12, 44, 170, and 320 mg/liter as CaCO3). The eyed-egg stage was one of the most resistant stages tested, and the sac-fry stage was one of the least resistant. Increased water hardness decreases toxicity to all stages. The LC50’s range from 0.532 mg/liter to 40.0 mg/liter depending upon life stage, water hardness, and duration of exposure. The margin of safety for coexisting species exposed to TFM ranges from 3.2 to 4.1 in natural waters. The margin of safety for early life stages of rainbow trout and larval lamprey under controlled laboratory conditions ranges from 4.2 to 12.2. Therefore, all six early life stages of rainbow trout are safe in minimum lampricidal concentrations of TFM.

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Effects of fish size and route of infection on virulence of a Danish Yersinia ruckeri O1 biotype 2 strain in rainbow trout (Oncorhynchus mykiss)

Aquaculture ◽

10.1016/j.aquaculture.2019.01.041 ◽

2019 ◽

Vol 503 ◽

pp. 519-526 ◽

Cited By ~ 7

Author(s):

Maki Ohtani ◽

Kasper Rømer Villumsen ◽

Helene Kragelund Strøm ◽

Anne Hjørngaard Lauritsen ◽

Bent Aalbæk ◽

...

Keyword(s):

Rainbow Trout ◽

Oncorhynchus Mykiss ◽

Yersinia Ruckeri ◽

Fish Size ◽

Rainbow Trout Oncorhynchus Mykiss ◽

Route Of Infection

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Effects of water hardness and pH on vanadium lethality to rainbow trout

Water Research ◽

10.1016/0043-1354(82)90246-9 ◽

1982 ◽

Vol 16 (10) ◽

pp. 1479-1488 ◽

Cited By ~ 22

Author(s):

D.H. Stendahl ◽

J.B. Sprague

Keyword(s):

Rainbow Trout ◽

Water Hardness

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Differences in Swimming Performance Among Strains of Rainbow Trout (Salmo gairdneri)

Journal of the Fisheries Research Board of Canada ◽

10.1139/f77-048 ◽

1977 ◽

Vol 34 (2) ◽

pp. 304-307 ◽

Cited By ~ 16

Author(s):

Allan E. Thomas ◽

Michael J. Donahoo

Keyword(s):

Growth Rate ◽

Rainbow Trout ◽

New Zealand ◽

Swimming Performance ◽

Salmo Gairdneri ◽

Swimming Ability ◽

Fish Swimming ◽

Fish Size ◽

Swimming Time ◽

Performance Profiles

Swimming performance profiles, relating fish size to swimming time, were established for three strains of rainbow trout (Salmo gairdneri). No differences were found in slope of regressions; only in level at each size of fish. Swimming performances of New Zealand and Sand Creek strains did not differ, but were superior to the Manchester strain. In stamina results from 189-day-old fish from individual matings of seven strains and various crosses, similar strains and crosses had closely matching profiles whereas profiles of unrelated groups were variable. Comparison of slowest, average, and fastest growing fish within the New Zealand strain showed that swimming ability was not related to growth rate.

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RNA/DNA ratios in white muscle as estimates of growth in rainbow trout held at different temperatures

Canadian Journal of Zoology ◽

10.1139/z90-221 ◽

1990 ◽

Vol 68 (7) ◽

pp. 1494-1498 ◽

Cited By ~ 31

Author(s):

Moira M. Ferguson ◽

Roy G. Danzmann

Keyword(s):

Growth Rate ◽

Rainbow Trout ◽

Oncorhynchus Mykiss ◽

White Muscle ◽

Specific Growth ◽

Fish Size ◽

Rainbow Trout Oncorhynchus Mykiss ◽

Different Temperatures ◽

Specific Growth Rates ◽

Rna And Dna

The concentrations of RNA, DNA, and protein in white muscle from 240 uniquely tagged rainbow trout (Oncorhynchus mykiss) held at three temperatures (5, 8 (control), and 11 °C) were measured. Both RNA and RNA/DNA ratios were better predictors of recent length- and weight-specific growth rates than they were of absolute fish size. Furthermore, RNA concentrations were better predictors of growth than RNA/DNA ratios. The strength of the regression between either RNA/DNA ratio or RNA and growth rate did not differ consistently among temperatures. Fish reared at warmer temperatures had lower concentrations of RNA for both a given growth rate and a given DNA concentration compared with cold-reared trout. Warm-reared fish also had lower concentrations of DNA and higher protein/DNA ratios than cold-reared trout when fish size was standardized. The concomitant decrease in both RNA and DNA concentrations resulted in marginally lower RNA/DNA ratios in warm-reared fish.

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