Cytological and Histological Studies on the Hybrid of Platichthys stellatus X Parophrys vetulus, with Notes on Its Backcross to P. vetulus

An investigation to determine what species of diatoms are used as food by different species of copepods: Calanus tonsus, Euchaeta japonica, Metridia lucens, Harpacticus uniremis, and Diosaccus spinatus. Also to determine the food chains between diatoms, copepods, and the following fish: Pacific herring, Clupea pallasii; chum salmon, Oncorhynchus keta; spring salmon, O. tschawytscha; dogfish, Squalus suckleyi; ling cod, Ophiodon elongatus; rockfish, Sebastodes caurinus; starry flounder, Platichthys stellatus; lemon sole, Parophrys vetulus; yellow-finned surffish, Damalichthys vacca; blue perch, Taeniotoca lateralis, and yellow shiner, Cymatogaster aggregatus. Stomach, intestines, and excreta were examined for the presence of diatoms. Almost all the common diatoms were found to be used as food by the copepods. The copepods and herring were found to be important links in the food chains between diatoms and the larger fishes.

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Biosynthesis of Trimethylammonium Compounds in Aquatic Animals: IV. Precursors of Trimethylamine Oxide and Betaine in Marine Teleosts

Journal of the Fisheries Research Board of Canada ◽

10.1139/f64-069 ◽

1964 ◽

Vol 21 (4) ◽

pp. 765-771 ◽

Cited By ~ 16

Author(s):

E. Bilinski

Keyword(s):

Metabolic Pathways ◽

Sodium Acetate ◽

Sodium Formate ◽

Whole Body ◽

Platichthys Stellatus ◽

Trimethylamine Oxide ◽

Dragendorff Reagent ◽

Limited Degree ◽

Parophrys Vetulus

An in-vivo study was made of potential precursors of trimethylamine oxide (TMAO) in marine teleosts (lemon sole, Parophrys vetulus, and starry flounder, Platichthys stellatus). C14-labelled compounds were administered intraperitoneally and the incorporation of tracer into TMAO, isolated from the whole body, was determined. Trimethylamine (TMA)-C14 was found to be a much better precursor than the other compounds tested. A limited labelling of TMAO was observed after administration of γ-butyrobetaine-methyl-C14, betaine-methyl-C14 and methionine-methyl-C14. There was little or no incorporation of C14 into TMAO after administration of methylamine-C14, carnitine-methyl-C14, gIycine-2-C14, sodium formate-C14, sodium acetate-1-C14, sodium acetate-2-C14 and NaHCO3-C14. The conversion of choline-methyl-C14 to TMAO was higher after intraperitoneal than after intramuscular injection and only trace amounts of radioactivity were found after intravenous injection. The results provide support for formation of TMAO in fish by oxidation of TMA but they give no clear indication for metabolic pathways leading to this oxidative step.Betaine was isolated from fish after administration of choline-methyl-C14, methionine-methyl-C14 and glycine-2-C14. Evidence of extensive conversion of choline to betaine was obtained. Betaine also was found to be labelled after administration of methionine-methyl-C14, but only a limited degree of labelling was observed after administration of glycine-2-C14. The results indicate that betaine is formed by oxidation of choline in fish.A modification of the Dragendorff reagent for use as a spray for detecting trimethylammonium compounds on paper chromatograms is described.

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Scale Thickness Predicts Skin Puncture-Force Resistance in Three Pleuronectiform Fishes

Integrative Organismal Biology ◽

10.1093/iob/obz005 ◽

2019 ◽

Vol 1 (1) ◽

Author(s):

M R Minicozzi ◽

J Perez ◽

D S Kimball ◽

A C Gibb

Keyword(s):

A Priori ◽

Blind Side ◽

Puncture Resistance ◽

Scale Type ◽

Scale Thickness ◽

Physical Defense ◽

Platichthys Stellatus ◽

Puncture Force ◽

Mechanical Insult ◽

Parophrys Vetulus

Synopsis In fishes, the skin and scales provide a physical barrier to the external environment and must withstand direct physical insult from biotic and abiotic features of the habitat. Flatfishes likely rely heavily on their scales for physical defense because they rest directly on the substrate. Using a flatfish model, we asked: what are the effects of scale type and scale morphology on puncture force resistance? We also asked: are there morphological and functional differences between the eyed and blind sides in flatfishes and do the morphological and functional properties of scales vary with organism size? Using a large size range of three species of Pleuronectid flatfish (Isopsetta isolepis, n = 10; Parophrys vetulus, n = 10; and Platichthys stellatus, n = 12), we measured the force required to puncture the integument using a sample of skin+scales taken from the eyed and blind side of each individual. We also measured the diameter, area, and thickness of the scales of each individual. Scaling relationships (body length vs. variable of interest) were derived for each species and compared with a priori expectations of geometric similarity. We found no relationship between scale type and puncture resistance and no differences in morphological parameters or puncture resistance between the eyed and blind side within a given species. These flatfish species do vary in their ability to withstand puncture forces; however, once scale thickness is taken into account, species differences disappear. Thus, the ability of a flatfish to withstand mechanical insult from puncture-forces varies depending on the thickness of the scale.

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Fin Erosion Disease of Starry Flounder (Platichthys stellatus) and English Sole (Parophrys vetulus) in the Estuary of the Duwamish River, Seattle, Washington

Journal of the Fisheries Research Board of Canada ◽

10.1139/f76-302 ◽

1976 ◽

Vol 33 (11) ◽

pp. 2577-2586 ◽

Cited By ~ 34

Author(s):

S. R. Wellings ◽

C. E. Alpers ◽

B. B. McCain ◽

B. S. Miller

Keyword(s):

Chronic Inflammation ◽

Environmental Variables ◽

Genetic Constitution ◽

English Sole ◽

Functional Surface ◽

Starry Flounder ◽

Platichthys Stellatus ◽

Chemical Pollutants ◽

Fin Rays ◽

Parophrys Vetulus

Fin erosion in the starry flounder (Platichthys stellatus) and English sole (Parophrys vetulus) of the Duwamish River, Washington, is characterized by ulcerating chronic inflammation and fibrosis with resorption of fin rays. The end result is deformation, shortening, and retraction of residual fin tissue with loss of functional surface. We suggest that the incidence of fin erosion in a particular population is related to an interaction between genetic constitution and multiple environmental variables, including a variety of chemical pollutants.

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A Comparison of Skin Tumors in Three Species of Flounders

Journal of the Fisheries Research Board of Canada ◽

10.1139/f71-190 ◽

1971 ◽

Vol 28 (9) ◽

pp. 1241-1251 ◽

Cited By ~ 9

Author(s):

G. E. McArn ◽

S. R. Wellings

Keyword(s):

Age Groups ◽

Skin Tumors ◽

Single Specimen ◽

English Sole ◽

Tumor Bearing ◽

Platichthys Stellatus ◽

Similar Disease ◽

History Of ◽

Hippoglossoides Elassodon ◽

Parophrys Vetulus

A study of the natural history of skin tumors occurring on two species of Pleuronectidae was conducted in the waters of Bellingham Bay, Washington. Twelve collections at monthly intervals indicated that 4.8% of 1977 English sole (Parophrys vetulus) and 2.4% of 2946 starry flounders (Platichthys stellatus) were tumorous. Three types of tumors were observed, and were classified as angioepithelial nodules, epidermal papillomas, or angioepithelial polyps, according to nomenclature previously established by other workers. The angioepithelial nodule was found on fish in the 1st year of life but not on fish older than 1 year. Epidermal papillomas usually occurred on fish that were 1 year or older, as did the angioepithelial polyps. The incidence of tumor-bearing fish, and the average number of tumors on a single specimen was greatest during the 1st year of life and decreased progressively in older age-groups. Tumors were more likely to occur on the pigmented side than on the nonpigmented side of the fish. The results of this study were compared and contrasted with a similar disease previously described on Hippoglossoides elassodon, the flathead sole.

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