the absorption of hydrophobic chemicals across perfused rainbow trout gills: methodological aspects.the absorption rates of 4-bromophenol, 2,4-dibromophenol, 3,4,5-trichloroguaiacol, and tetrachloroveratrol across fish gill epithelium have been measured in a perfused gill preparation from rainbow trout (oncorhynchus mykiss). in additional experiments the absorption rate of tetrachloroveratrol was measured in free swimming fish. the absorption rates were perfusion limited in gills perfused with a saline containing 2% polyvinylpyrrolidone mw 40,000 (pvp-40) as a plasma protein substitute. replac ...19921282872
stimulation of hepatic thyroxine 5'-deiodinase activity in rainbow trout (oncorhynchus mykiss) by pacific salmon growth hormone.1. growth hormone extracted from pacific salmon pituitaries (sgh) was injected intra-peritoneally into rainbow trout to determine sgh effects on plasma levels of thyroxine (t4), 3,5,3'-triiodothyronine (t3) and properties of the hepatic 5'-deiodinase enzyme (5'-d) responsible for t4 to t3 conversion. 2. after 24 hr, sgh (0.1 or 0.5 microgram/g) did not alter the plasma t4 level or 5'-d, km, but elevated plasma t3 and especially 5'-d vmax. 3. thus sgh, like the previously tested human gh, acutely ...19921351442
dietary arginine requirement of young rainbow trout (oncorhynchus mykiss).1. two growth trials were conducted with young rainbow trout (oncorhynchus mykiss) to determine the dietary arginine requirement under conditions of rapid weight gain at 15 degrees c. 2. the growth requirement does not exceed 4.2 g arginine/16 g dietary nitrogen and, thus, is much lower than the value of 6.0 g arginine/16 g dietary nitrogen presently listed by the nrc for chinook salmon and widely applied to all salmonids. 3. comparison of the present results with the arginine requirement of the ...19921351818
chronic fasting reduces the response of the thyroid to growth hormone and tsh, and alters the growth hormone-related changes in hepatic 5'-monodeiodinase activity in rainbow trout, oncorhynchus mykiss.chronically fasted rainbow trout (oncorhynchus mykiss) had significantly lower plasma l-thyroxine (t4) and triiodo-l-thyronine (t3), and higher plasma growth hormone (gh) concentrations than fed animals. fasted and fed trout were administered bovine thyrotropic hormone (btsh), native ovine gh (ogh), or recombinant human gh (rhgh) alone, or gh in combination with btsh to further study the effects of food deprivation on the activity of the pituitary-thyroid axis and on the control of hepatic t3 pr ...19921426938
the primary structure of piscine (oncorhynchus mykiss) retinol-binding protein and a comparison with the three-dimensional structure of mammalian retinol-binding protein.1. the primary structures of two variants of rainbow trout (oncorhynchus mykiss) plasma retinol-binding protein (rbp) were determined and found to be approximately 60% identical with those of both human and xenopus laevis rbps. the comparable sequence similarities that we have found agree with the estimate of similar divergence times between bony fishes and mammals and between bony fishes and amphibians. the two piscine rbp variants differ by six amino acid substitutions at positions that are no ...19921483476
rainbow trout mitochondrial dna: sequence and structural characteristics of the non-coding control region and flanking trna genes.we have determined the sequence of the 1003-bp control region (also referred to as the 'displacement-loop region') and flanking trna genes in the mitochondrial dna (mtdna) of the rainbow trout, oncorhynchus mykiss. this region has the same overall structure (i.e., trnt-trnp-control region-trnf) as in mammalian and amphibian (xenopus laevis) mitochondrial (mt)dnas. the trout control region contains apparent homologues of the conserved sequence blocks (csb) and termination-associated sequences ide ...19921511893
[antibacterial resistance induced by injection of ascitic fluid (with igm partially removed) and natural monoclonal antibodies of human origin in rainbow trout].human monoclonal immunoglobulins m from myeloma shown to have the typical polyspecificity of natural antibodies, were precipitated from the ascitic fluid that originally contained them. the igm and their supernatant were injected in parallel, intraperitoneally into rainbow trout (oncorhynchus mykiss) to test passive protection against experimental furunculosis. protection was observed in both cases (significant protection at 2%). however, only trout treated with igm were still protected against ...19921559182
intra- and extra-cellular sources of t3 binding to putative thyroid hormone receptors in liver, kidney, and gill nuclei of immature rainbow trout, oncorhynchus mykiss.the sources of extracellular and intracellular 3,5,3'-triiodo-l-thyronine (t3) binding to putative thyroid hormone receptors in liver, kidney, and gill nuclei were determined in vivo for immature rainbow trout at 12 degrees c. both [131i]t3 and [125i]t4 were injected intraperitoneally, the plasma and tissues were examined at isotopic equilibrium at 20 h, and the proportions of intracellular [125i]t3 and extracellular [131i]t3 saturably bound in the nucleus were determined. comparable total amoun ...19921583450
cortisol content of eggs and larvae of teleosts.the whole-animal content of the cortisol was measured in embryos and larvae of tilapia (oreochromis mossambicus), rainbow trout (oncorhynchus mykiss), ayu (plecoglossus altivelis), milkfish (chanos chanos), and yellowfin bream (acanthropagrus latus) by radioimmunoassay following the validation of an extraction method. the total cortisol content in tilapia was 50.3 +/- 19.1 pg immediately following fertilization, then decreased abruptly and maintained a lower level of 10-17 pg until larval hatchi ...19921601267
the acute influence of ingested thyroid hormones on hepatic deiodination pathways in the rainbow trout, oncorhynchus mykiss.juvenile rainbow trout were fed once daily with trout pellets supplemented with l-thyroxine (t4) or 3,5,3'-triiodo-l-thyronine (t3) and the effects on plasma t4 and t3 levels and hepatic 5'-monodeiodinase (5'd) activity determined after 1, 2, or 3 days. in all cases t3 (12 ppm) elevated plasma t3 and caused a significant reduction in the functional level (vmax) of 5'd with no change in enzyme affinity (km). after 3 daily meals (3 ppm t3), 5'd activity fell to 52% of control levels. in most insta ...19921577241
hplc analysis of in vitro hepatic deiodination products of thyroid hormones in the rainbow trout, oncorhynchus mykiss.reverse-phase hplc employing five different solvent systems was used to determine the 125i-labeled products formed in rainbow trout by in vitro incubation at 12 degrees of the hepatic microsome fraction with l-thyroxine (t4) labeled with 125i in the outer phenyl ring. trout were starved for 2 weeks or fed a 2% ration. the only labeled products identified during incubation for 7.5-70 min over a t4 substrate range of 0.03-0.5 nm were 125i- and 3,5,[125i]3'-triiodo-l-thyronine (t3). these products ...19921577240
sequential development of the immune response in rainbow trout [oncorhynchus mykiss (walbaum, 1792)] to experimental plerocercoid infections of diphyllobothrium dendriticum (nitzsch, 1824).development of the inflammatory response of rainbow trout to experimental infections with diphyllobothrium dendriticum plerocercoids is described using light and electron microscopy. the cellular response to plerocercoids occurred within 2 weeks post-infection (p.i.). this was followed by an increase in leucocyte numbers during weeks 3-6 p.i., with full encapsulation of plerocercoids by week 6 p.i. neutrophils were the first leucocytes to engage the developing plerocercoid, followed by large inf ...19921614733
influence of hypophysectomy, castration, fasting, and spermiation on sbp concentration in male rainbow trout (oncorhynchus mykiss).the influence of different experimental and physiological conditions on sex steroid binding protein (sbp) concentrations in the blood (and in hepatic and testicular cytosols) has been studied on male rainbow trout. sbp was measured with a specific binding assay. the aim was to further understanding of regulation of the sbp and in particular to determine the respective influences of reproductive and metabolic status. twelve days after hypophysectomy, pituitary and steroid hormones were dramatical ...19921563611
a comparative study of the host-parasite relationship of pomphorhynchus patagonicus (acanthocephala) in two species of fish from lake rosario (chubut, argentina).some aspects of the host-parasite relationships of pomphorhynchus patagonicus (acanthocephala) in 2 fish species from lake rosario (chubut, argentina) were studied. the fish species patagonina hatcheri (atherinidae) is autochthonous, and oncorhynchus mykiss (salmonidae) is introduced. the host species appears to influence attachment, size, sexual maturity, and distribution of parasites along the digestive tract. in p. hatcheri, an effective major host, parasites are attached firmly to the wall o ...19921635031
effects of human insulin-like growth factor-i on release of growth hormone by rainbow trout (oncorhynchus mykiss) pituitary cells.a recombinant human igf-i (rhigf-i) was applied to primary cultures of rainbow trout pituitary cells. in wells containing 3 x 10(4) and 6 x 10(4) cells/well, rhigf-i inhibited basal gh release both in short (6 h) and long (12 and 24 h) exposures. the decline in gh release was dose-dependent over the range of 0.01 and 100 mm. the combination of rhigf-i and low concentrations of synthetic somatostatin (srif) enhanced the inhibitory effect of rhigf-i in an additive manner. any appreciable effect of ...19921640199
neutrophil, glass-adherent, nitroblue tetrazolium assay gives early indication of immunization effectiveness in rainbow trout.neutrophil activity in rainbow trout (oncorhynchus mykiss) is increased upon antigenic stimulation with the yersinia ruckeri o-antigen bacterin. the characteristics of neutrophil attachment to glass and nitroblue tetrazolium (nbt) staining were used to determine the effectiveness of immunization programs with fingerling rainbow trout. fish immunized by intraperitoneal injection with doses of 100, 10, or 1 microgram of the bacterin showed the highest responses in that order in numbers of glass ad ...19921546446
cloning and sequence analysis of the cdna encoding p-450 aromatase (p450arom) from a rainbow trout (oncorhynchus mykiss) ovary; relationship between the amount of p450arom mrna and the production of oestradiol-17 beta in the ovary.the enzyme aromatase p-450 (p450arom) catalyses the conversion of androgen to oestrogen. a cdna insert encoding p450arom was isolated from a rainbow trout (oncorhynchus mykiss) ovary cdna library. the insert was sequenced and found to contain an open-reading frame predicted to encode a protein of 522 amino acid residues. the deduced polypeptide is 52% homologous with human, mouse and rat p450arom and 53% homologous with that of chicken. the insert was confirmed to encode p450arom by introducing ...19921543534
[triiodothyronine is needed for the acclimatization of brown trout (salmo trutta) or rainbow trout (oncorhynchus mykiss) to seawater].brown and rainbow trout, held in freshwater at 13 +/- 1 degrees, were injected, every 3 days, with iopanoic acid (iop: 5 mg/100 g body wt), an inhibitor of deiodination of thyroxine (t4) to triiodothyronine (t3). one group of iop-treated rainbow trout was immersed in t3 (20 micrograms/l water). in iop trout, plasma t3 fell to very low levels by day 7, while changes in t4 levels were less marked. in iop + t3 trout plasma t3 increased fivefold, plasma t4 being unchanged. no mortality occurred and ...19921521165
isolation of an acute-phase phosphorylcholine-reactive pentraxin from channel catfish (ictalurus punctatus).1. channel catfish (ictalurus punctatus) serum contains a protein that precipitates pneumococcal c-polysaccharide (cps) in a calcium-dependent fashion. 2. the serum titer of this protein follows an acute-phase pattern in catfish injected with turpentine. 3. a non-glycosylated, phosphorylcholine (pc)-reactive protein (prp) with molecular mass ca 100 kda, was isolated from channel catfish acute-phase sera by affinity chromatography on pc-sepharose 4b. 4. contaminating proteins with molecular masse ...19921499290
purification and characterization of two chymotrypsin-like proteases from the pyloric caeca of rainbow trout (oncorhynchus mykiss).1. two chymotrypsins, called chymotrypsin i and ii, were purified from the pyloric caeca of rainbow trout, by (nh4)2so4 fractionation, hydrophobic interaction chromatography (phenyl-sepharose) and ion-exchange chromatography (deae-sepharose). 2. the approximate molecular weights of chymotrypsin i and ii were 28,200 (+/- 1200) and 28,800 (+/- 900), respectively, as determined by sds-page and their isoelectric points were about 5. 3. the ph optima of the enzymes were centered around nine, when ass ...19921499272
enrichment of metabolites in the cerebrospinal fluid of cod (gadus morhua) following oral administration of hexachlorobenzene and 2,4',5-trichlorobiphenyl.the disposition of 14c-labelled hexachlorobenzene (hcb) and 2,4',5-trichlorobiphenyl (tricb) was studied in cod (gadus morhua) and rainbow trout (oncorhynchus mykiss). for both compounds tape section autoradiography revealed substantial amounts of radiolabelled material in the central nervous system (cns) of cod, whereas only traces of radioactivity were observed in the cns of rainbow trout. furthermore, an enrichment of radiolabelled compound in the cerebrospinal fluid (csf) was observed in the ...19921480551
isolation and primary structure of gastrin-releasing peptide from a teleost fish, the trout (oncorhynchus mykiss).immunohistochemical studies have established that fish gastrointestinal tissues contain peptides with gastrin-releasing peptide (grp)/bombesin-like immunoreactivity, but the molecular nature of this material is unclear. in this study, the most abundant peptide that was immunoreactive towards an antiserum raised against pig grp was isolated in pure form from an extract of the stomach of the rainbow trout (oncorhynchus mykiss). the primary structure of the peptide was established as: ser-glu-asn-t ...19921480521
vector specificity of trypanosoma catostomi and its infectivity to freshwater fishes.trypanosoma catostomi was found in 36.2% of 558 white suckers (catostomus commersoni) from ontario, canada. the abundance of actinobdella inequiannulata was 35% (68 leeches/197 suckers examined for leeches). the susceptibility of 3 species of leeches (hemiclepsis marginata, desserobdella phalera, and a. inequiannulata) and 7 species of fishes (c. commersoni, amia calva, anguilla rostrata, ictalurus nebulosus, oncorhynchus mykiss, perca flavescens, and esox lucius) to infection with t. catostomi ...19921738075
phosphofructokinase from white muscle of the rainbow trout, oncorhynchus mykiss: purification and properties.phosphofructokinase was purified and characterized from the white skeletal muscle of rainbow trout oncorhynchus mykiss. purification involved three steps: ion-exchange chromatography on hydroxyapatite and affinity chromatography on phosphocellulose and atp-agarose. a final specific activity of 75 units per mg of protein at 22 degrees c and ph 7.2 with 40% recovery was obtained. the purified enzyme gave a single band on sds-page with a subunit molecular mass of 76.5 +/- 0.6 kda. based on gel filt ...19921477103
zona radiata proteins are synthesized by rainbow trout (oncorhynchus mykiss) hepatocytes in response to oestradiol-17 beta.the present study delineates the origin of the three major proteins constituting the rainbow trout (oncorhynchus mykiss) zona radiata. intraperitoneal administration of oestradiol-17 beta induced the appearance in the blood from juvenile fish (both sexes) of proteins immunoreactive to rabbit antisera against zona radiata proteins (zr proteins). these proteins had similar molecular weights to the zr proteins (alpha, 60 kda; beta, 55 kda; and gamma, 50 kda). primary hepatocyte cultures from fish t ...19921474336
characterization of peptides related to neuropeptide tyrosine and peptide tyrosine-tyrosine from the brain and gastrointestinal tract of teleost fish.neuropeptide y was isolated from the brain of the atlantic cod, gadus morhua and its primary structure established as tyr-pro-ile*-lys-pro-glu*-asn-pro-gly-glu10-asp-ala-pro-ala-asp*-g lu*-leu*-ala- lys*-tyr20-tyr-ser-ala-leu-arg-his-tyr-ile-asn-leu30-ile-thr -arg-gln-arg-tyr- conh2. residues denoted by an asterisk are different from the corresponding sequence of human neuropeptide y. a structurally similar peptide was isolated from the brain of the trout, oncorhynchus mykiss. trout neuropeptide ...19921459125
the effects of computer-controlled shadow stimuli on the success of cercarial transmission by cryptocotyle lingua (digenea: heterophyidae).pectoral fins from juvenile rainbow trout (oncorhynchus mykiss) were used in a bioassay, the object of which was to quantify the effect of simulated shadow stimuli on the transmission success of the cercariae. for a period of 60 min, parasites and fins were exposed to a sequence of computer-controlled shadow stimuli, continuous light or total darkness, and subsequently the number of infections was counted. trials were conducted with cercariae 1, 12 and 24 h old. within the constraints of the exp ...19921454422
identification of a second insulin-like growth factor in a fish internal portion of insulin-like growth factor (igf) amplified from the total cdna of rainbow trout (oncorhynchus mykiss) liver by a pcr was used to screen a rainbow trout liver cdna library, and recombinant clones encoding two distinct igfs were isolated. on the basis of a 98.7% nucleotide and 98.3% predicted amino acid identity to coho salmon igf-i, one cdna sequence was identified as rainbow trout preproinsulin-like growth factor i (rtigf-i). the second cdna sequence shared 46.1% and 43.3% ...19921409585
the energetic cost of protein synthesis in isolated hepatocytes of rainbow trout (oncorhynchus mykiss).to establish the energetic cost of protein synthesis, isolated trout hepatocytes were used to measure protein synthesis and respiration simultaneously at a variety of temperatures. the presence of bovine serum albumin was essential for the viability of isolated hepatocytes during isolation, but, in order to measure protein synthesis rates, oxygen consumption rates and rna-to-protein ratios, bsa had to be washed from the cells. isolated hepatocytes were found to be capable of protein synthesis an ...19921401333
effects of nutritional state, insulin, and glucagon on lipid mobilization in rainbow trout, oncorhynchus mykiss.the effects of nutritional state, insulin, and glucagon on lipid mobilization were determined in rainbow trout, oncorhynchus mykiss. in nutritional state experiments, fish were either fed continuously (except 24 to 36 hr prior to experimentation) with commercial trout chow or fasted for 4 weeks. lipase activity in liver tissue isolated from fasted fish and cultured for 5 hr was greater than that in tissue isolated from fed fish and cultured. the presence of glucose (5.55 mm) in the incubation me ...19921398015
dexamethasone stimulates release of an anp-like substance from rainbow trout cardiocytes.a substance that cross-reacts with antiserum to human atrial natriuretic peptide (anp) is found in fish hearts. this anp-like material increases sodium output from the gill and kidney while inhibiting sodium uptake in the gut. mammalian anp secretion is stimulated by glucocorticoids, and cortisol injection increases sodium output in salt-loaded fish. therefore, we wanted to determine if the release of anp in fish is sensitive to dexamethasone. ventricle cardiocytes from the rainbow trout oncorhy ...19921387296
effect of sublethal concentrations of four chemicals on susceptibility of juvenile rainbow trout (oncorhynchus mykiss) to saprolegniosis.the effects of sublethal concentrations of a variety of chemicals on the susceptibility of rainbow trout (oncorhynchus mykiss) juveniles to saprolegnia parasitica infection was examined. sublethal concentrations of un-ionized ammonia (0.05 mg/liter) and nitrite (0.12 mg/liter) increased fish susceptibility after 10 days of exposure to the toxin, this increase being higher for ammonia (75% and 20% morbidity) than for nitrite (20% and 0% morbidity, respectively) with inoculum doses of 1.4 x 10(6) ...19911872610
immune complex-mediated glomerulonephritis associated with bacterial kidney disease in the rainbow trout (oncorhynchus mykiss).rainbow trout (oncorhynchus mykiss) developed a post-infectious chronic membranous glomerulonephritis 15 months after they had been experimentally infected with renibacterium salmoninarum. histologically, peritubular and periglomerular fibrosis, hypercellular glomeruli with occluded bowman's space, and partial or complete adhesion to bowman's capsule were constant features. electron microscopy revealed thickened glomerular basement membranes with spikes accompanied by finely granular electron-de ...19921385916
mhc class ii beta-chain expression in the rainbow trout.a cdna clone corresponding to the mhc class ii beta-chain of the rainbow trout (oncorhynchus mykiss) has been isolated and used in restriction fragment length polymorphism (rflp) studies in a family of full siblings of rainbow trout. a very simple rflp pattern was detected, suggesting segregation of a homozygote aa genotype and a heterozygote ab genotype. the mhc class ii beta-chain of the rainbow trout seems to be transcribed in the same type of cells as class ii genes of higher vertebrates eve ...19921351315
pharmacokinetics of enrofloxacin in fingerling rainbow trout (oncorhynchus mykiss).the pharmacokinetics of intravenously and orally administered enrofloxacin was determined in fingerling rainbow trout (oncorhynchus mykiss). doses of 5 or 10 mg enrofloxacin/kg body weight were administered intravenously to 26 fish for each dose and blood was sampled over a 60-h period at 15 degrees c. two groups of fish were treated orally with 5, 10, or 50 mg/kg (80 fish/dose at each temperature) and held at 15 degrees c or 10 degrees c during the 60-h sampling period. following intravenous ad ...19921315398
gyrodactylus bohemicus sp. n. (monogenea: gyrodactylidae) from oncorhynchus mykiss (walbaum) and salvelinus fontinalis (mitchill) (clupeiformes: salmonidae) in czechoslovakia.gyrodactylus bohemicus sp. n (gyrodactylidae: monogenea) is described from the fins, skin and gill filaments of oncorhynchus mykiss (walbaum) and salvelinus fontinalis (mitchill) (clupeiformes: salmonidae) from a trout farm in czechoslovakia. g. bohemicus sp. n. is most closely related to g. thymalli zitnan, 1960 and g. magnus konovalov, 1967 in the shape of the anchors, the ventral and the dorsal bar, but can be distinguished from both these species by the shape of the marginal hook proper.19921291456
in vitro effect of levamisole on the neutrophil activity in rainbow trout (oncorhynchus mykiss).an in vitro immunization and cultivation method for fish spleen organ section was used to investigate the effects of levamisole on the neutrophil activity. after 10 days of culture with either 50 micrograms/ml, 25 micrograms/ml, 5 micrograms/ml or no levamisole in the media, the nonspecific defense reactions were measured by determining the metabolic activity of neutrophils by using the nitroblue tetrazolium test, and phagocytic and adherence indexes by incubating the fish cells with suspensions ...19921285074
immunostimulants added to injected aeromonas salmonicida bacterin enhance the defense mechanisms and protection in rainbow trout (oncorhynchus mykiss).immunostimulants were given to rainbow trout for assaying effects on modulating non-specific defense mechanisms, specific immune response, and protection levels against pathogen challenge with aeromonas salmonicida. three drugs, levamisole (an approved veterinary drug in the usa), a quaternary ammonium compound (qac), and a short-chain polypeptide (isk) were found to affect the non-specific defense mechanism activities, which were measured by changes in circulatory neutrophil and phagocytic acti ...19921280879
properties of t4 5'-deiodinating systems in various tissues of the rainbow trout, oncorhynchus mykiss.l-thyroxine (t4) 5'-monodeiodinase (5'd) activity was examined in the microsomal fractions of liver, kidney, gill, white skeletal muscle, and red blood cells (rbc) of fed rainbow trout held in freshwater at 12 degrees. two distinct 5'd systems were established and were examined at low (0.08-1.3 nm) or high (1.6-25 nm) t4 substrate ranges. the low substrate 5'd occurred in liver, gill, and muscle, but not in kidney or rbc. the ph optimum was 7.0 and the optimum dithiothreitol (dtt) level ranged f ...19921601281
the effects of thyroid hormones and starvation on hepatic mitochondrial nucleic acids of rainbow trout (oncorhynchus mykiss).twenty four hours after an intraperitoneal injection of thyroxine (t4; 4.4, 44 ng/g body wt) or triiodothyronine (t3; 3.3, 33 ng/g body wt), dna and rna were significantly reduced in isolated liver mitochondria of rainbow trout. total liver dna was increased with the higher doses in both t4- and t3-injected specimens while total rna was significantly reduced with the same doses. total circulating plasma t4 was reduced with the injections of t3 or starvation, and plasma t3 was increased severalfo ...19911936929
thyroid hormone increases transcription of growth hormone mrna in rainbow trout pituitary.treatment of young rainbow trout (oncorhynchus mykiss) fish for one week with thyroid hormone (t3) (3,3',5-triiodo-l-thyronine) increased the steady state levels of mrna for growth hormone in the pituitary 3-4 times as compared to control groups. the steady state levels of growth hormone in the pituitary and in the plasma, were not significantly altered. this implicates the existence in fish of a molecular mechanism of transcriptional stimulation of the gh gene by thyroid hormone, similar to tha ...19921612552
effects of short-term 17 beta-estradiol treatment on the properties of t4-binding proteins in the plasma of immature rainbow trout, oncorhynchus determine the effects of 17 beta-estradiol (e2) on the properties of the plasma proteins that bind l-thyroxine (t4) immature rainbow trout, oncorhynchus mykiss, were injected intraperitoneally on days 0 and 3 with 0.5 mg e2-3-benzoate/100 g body weight, and plasma was sampled on days 4, 7, or 12. control trout received peanut oil alone. e2 caused a small but significant decrease in the free t4 index. saturation analysis on miniature g-25 sephadex columns revealed at least two major t4-binding ...19921624912
isolation and characterization of the major glycosphingolipids from the liver of the rainbow trout (oncorhynchus mykiss): identification of an abundant source of 9-o-acetyl gd3.the carbohydrate structures of the major glycosphingolipids from the liver of the rainbow trout oncorhynchus mykiss have been examined. we have isolated and identified four major neutral (glucosylceramide, galactosylceramide, lactosylceramide, and globoside) and five acidic (sulfatide, gm3, gm2, gd1a, and 9-o-acetyl gd3) glycosphingolipids from trout liver. they have been characterized by 1h nuclear magnetic resonance spectroscopy, methylation analysis, fast atom bombardment mass spectrometry, a ...19911989525
analysis of ras gene mutations in rainbow trout liver tumors initiated by aflatoxin b1.the suspect human hepatocarcinogen aflatoxin b1 (afb1) is a well-known potent initiator of hepatic tumors in rainbow trout (oncorhynchus mykiss). both hepatocellular carcinomas and mixed hepatocellular/cholangiocellular carcinomas are induced by afb1 in trout, with the mixed form predominating. we previously isolated two c-ras genes from trout liver cdna, and in the present study we analyzed dna from 14 afb1-induced trout liver tumors for point mutations in exon 1 of both genes. using the polyme ...19911645972
development of fish peritoneal macrophages as a model for higher vertebrates in immunotoxicological studies. i. characterization of trout macrophage morphological, functional, and biochemical properties.the immune defense mechanisms of fish are not as well characterized as those of mammals but seem to be related and similarly competent. because of this, there is an increased interest in the immune responses of fish as models for higher vertebrates in immunotoxicological studies. prior to such studies, baseline criteria for specific components of the immune response needed to be established. for this study, we have examined trout macrophage morphology using light and scanning electron microscopy ...19911649778
comparative metabolic profiling of chloramphenicol by isolated hepatocytes from rat and trout (oncorhynchus mykiss).1. isolated liver cells from rat and rainbow trout were used to study the biotransformation of labelled chloramphenicol (cp). 2. the 3h-cp metabolic rates were 1.7 nmol/hr/10(6) rat hepatocytes and 0.2 nmol/hr/10(6) trout hepatocytes. 3. in rat, as in trout liver cells, the major metabolite was cp-glucuronide. in addition to this conjugate, cp-base, cp-alcohol and cp-oxamic acid were detected in significant amounts. 4. these results are compared with in vivo data on cp metabolism previously obta ...19911687566
in vitro immunostimulation of rainbow trout (oncorhynchus mykiss) spleen cells with in vitro immunization and cultivation method for fish spleen organ sections was used to investigate the effects of levamisole on the immune response. after 10 days of culture with either 50 micrograms/ml, 25 micrograms/ml, 5 micrograms/ml or no levamisole in the media, the nonspecific defense reactions were measured by determining the metabolic activity of neutrophils by using the nitroblue tetrazolium test, and phagocytic and adherence indexes by incubating the fish cells with suspensions of ...19901695158
expression of immunoreactive glutathione s-transferases in hepatic neoplasms induced by aflatoxin b1 or 1,2-dimethylbenzanthracene in rainbow trout (oncorhynchus mykiss).the expression of immunoreactive glutathione s-transferase (gst) was examined in hepatic neoplasms induced in rainbow trout by aflatoxin b1 (afb) or 1,2-dimethylbenzanthracene (dmba). tumors were induced in adult trout by continuous dietary exposure to 8 p.p.b. afb1 for 12 months or embryo bath exposure to dmba (5 p.p.m. for 24 h, 3 times with 12 h intervals between exposures). polyclonal antiserum specific for the two major trout hepatic gst subunits in trout liver was produced by immunizing ra ...19901702371
the role of alpha 2-macroglobulin in furunculosis: a comparison of rainbow trout and brook trout.1. the molecular basis for the high survival rate of rainbow trout, oncorhynchus mykiss, infected with furunculosis was investigated. 2. alpha 2-macroglobulin (alpha 2m), a major serum protease inhibitor, was partially purified from rainbow trout and brook trout, salvelinus fontinalis, sera; the latter species shows marked disease susceptibility. 3. it is shown that a 10-fold species-based difference in alpha 2m inhibitory activity exists against a furunculosis associated bacterial protease. 4. ...19911714367
[parasitism in fishes and human riverside communities of the huillinco and natri lakes (great island of chiloé), chile].in april and december 1989, 35 fish from lake huillinco (42 degrees 48's, 74 degrees 02'w) and 36 fish from lake natri (42 degrees 48's, 73 degrees 50'w), in the great island of chiloé (chile) were examined. coprological samples from 159 persons, 17 dogs, 19 pigs and 4 cats from around both lakes were examined for diphyllobothrium spp. infection. in the lake huillinco the following helminths of fishes were determined: contracaecum sp. and hysterothylacium sp. in salmo trutta, cauque mauleanum an ...19902152358
degranulation of eosinophilic granule cells induced by capsaicin and substance p in the intestine of the rainbow trout (oncorhynchus mykiss walbaum).adult rainbow trout (oncorhynchus mykiss) were injected intraperitoneally with capsaicin, substance p, serotonin, or a control of saline vehicle or bovine serum albumin (0.5 microgram/g body weight). fish were sacrificed 30 min and 1, 2, and 4 h post-injection, the gut was dissected out, and a small section of the upper intestine was processed for electron microscopy. a significant proportion of eosinophilic granule cells (egcs) of the intestine were in close association with non-myelinated neur ...19911725861
immunosuppressive effect of infectious pancreatic necrosis virus on rainbow trout (oncorhynchus mykiss).the infectivity of infectious pancreatic necrosis virus (ipnv) for rainbow trout (oncorhynchus mykiss) mononuclear leukocyte subpopulations was investigated to determine the mechanisms of immunosuppression caused by the virus. ipnv was recovered from nylon wool-adherent, surface immunoglobulin (ig)-positive leukocytes of head kidney, spleen and peripheral blood collected from virus-inoculated fish with higher titers than non-adherent, ig-negative cells. non-adherent cell population showed mitoge ...19902177807
the piscine plasma retinol-binding protein. purification, partial amino acid sequence and interaction with mammalian transthyretin of rainbow trout (oncorhynchus mykiss) retinol-binding protein.1. retinol-binding protein (rbp) has been isolated from the pooled plasma or rainbow trouts (oncorhinchus mykiss) by gel filtration, hydrophobic interaction chromatography and ion-exchange chromatography. by this procedure two forms of the protein, both with a molecular mass (approximately 20 kda) similar to that of mammalian rbp, were purified to homogeneity. five amino acid substitutions have been found in the partial (about 60%) sequences of the two forms of trout rbp, which are presumably ac ...19921740159
cryptobia cataractae from the blood of semotilus atromaculatus: structure and division in the fish.a cryptobiid was found in the blood of 2 of 9 semotilus atromaculatus from a tributary of the saugeen river in ontario, canada. blood inoculation produced an infection in 2 uninfected s. atromaculatus but not in any oncorhynchus mykiss, catostomus commersoni, or carassius auratus. the flagellate was identified as cryptobia cataractae, based on host restriction. cryptobia cataractae occurred as slender and broad forms (body width 3.0-8.7 microns). the length of the anterior flagellum was equal to ...19902213407
identification and characterization of a zinc metalloprotease associated with invasion by the fish pathogen vibrio invasiveness-defective mutant of the fish-pathogenic bacterium vibrio anguillarum was isolated. compared with the wild type, this mutant had a 1,000-fold higher 50% lethal dose after immersion infection of rainbow trout, oncorhynchus mykiss, while after intraperitoneal infection, the mutant had only a 10-fold higher 50% lethal dose. in addition, the mutant showed a lower level of protease activity. two forms of the protease (pa and pb) were found after sodium dodecyl sulfate-polyacrylamide ge ...19902228244
in vivo and in vitro studies on sex steroid binding protein (sbp) regulation in rainbow trout (oncorhynchus mykiss): influence of sex steroid hormones and of factors linked to growth and metabolism.the respective roles of sex steroids and hormones related to growth and metabolism, on sbp regulation have been studied in rainbow trout. in vivo, oestradiol (e2) supplementation induces a slow but significant increase of plasma sbp concentration. testosterone or cortisol injections have no effect. in vitro, the steroid binding protein that accumulates in incubation medium of hepatic cell primary cultures has been characterized and found to be similar to blood sbp. its production is increased by ...19911751398
virulence and serum-resistance in different clonal groups and serotypes of yersinia ruckeri.the virulence in rainbow trout (oncorhynchus mykiss) of 32 isolates of yersinia ruckeri, representing a range of biotypes, serotypes, and omp-types, was examined. virulence was assayed in fish of average weight 7.7 g by bath challenge for 1 h with approximately 5 x 10(7) cells per ml. two of the six serotype o1 clonal groups of y. ruckeri, clones 2 and 5, were virulent, whereas the other four clonal groups, clones 1, 3, 4 and 6, as well as all serotype o2, o5, o6 and o7 isolates examined, were a ...19911771752
leucocyte migration in rainbow trout (oncorhynchus mykiss [walbaum]): optimization of migration conditions and responses to host and pathogen (diphyllobothrium dendriticum [nitzsch]) derived chemoattractants.a rainbow trout leucocyte-derived chemoattractant(s) was prepared and tested as a stimulant of leucocyte migration. it was used to optimize an in vitro leucocyte migration assay using a 48-well micro chemotaxis chamber. this assay has subsequently been used to test the chemoattractant activity of antigen extracts from the tegument of diphyllobothrium dendriticum plerocercoids and conditioned medium obtained after in vitro maintenance of live plerocercoids. leucocytes were found to have an increa ...19911773854
the acute effects of food and glucose challenge on plasma thyroxine and triiodothyronine levels in previously starved rainbow trout (oncorhynchus mykiss).the acute effects of a single meal on plasma l-thyroxine (t4) and 3,5,3'-triiodo-l-thyronine (t3) levels were examined in rainbow trout starved for 3 days. plasma t4 increased within 2 hr of food intake and remained elevated to 8 hr. plasma t3 was not altered consistently. feeding-induced elevations in plasma t4 were present only in trout weighing less than 250 g and if they consumed a ration exceeding 0.38% of body weight. postprandial elevations in plasma glucose paralleled those in plasma t4, ...19902332149
isolation of sockeye salmon growth hormone utilizing serum triiodothyronine enhancement in rainbow trout to monitor biological activity.growth hormone (gh) was isolated from sockeye salmon (oncorhynchus nerka) pituitary glands using established techniques of affinity and gel filtration chromatography, and preparative polyacrylamide gel electrophoresis. the gh activity was followed throughout the fractionation procedure with a bioassay based on the increase of serum triiodothyronine (t3) in rainbow trout (oncorhynchus mykiss), measured by radioimmunoassay (ria). amino-terminal amino acid sequence analysis and subsequent compariso ...19911808018
location and characterization of growth hormone binding sites in the central nervous system of a teleost fish (oncorhynchus mykiss).the binding of 125i-chinook salmon growth hormone (125i-sgh) to rainbow trout brain membranes was studied. specific binding was detected on telencephalon, thalamus-midbrain, cerebellum-medulla and hypothalamus. in all brain regions, specific binding was dependent on membrane protein concentration, being linear in the range of 250-2500 micrograms of membrane proteins (derived from 30-300 mg wet weight tissue). scatchard analysis evidenced a single class of high affinity (8.2 +/- 0.3-10 +/- 0.5 x ...19911842346
pseudomonas fluorescens isolated from the diseased rainbow trout, oncorhynchus mykiss.pseudomonas fluorescens was isolated from the diseased rainbow trout, oncorhynchus mykiss, in iwate prefecture. typical symptoms of the diseased fish were hemorrhage at the bases of fin and anal region, and internally, petechia of each organ, especially the intestine. this bacterium was pathogenic to rainbow trout and tilapia, sarotherodon niloticus.19892517962
site availability and density-dependent constraints on the acanthocephalan pomphorhynchus laevis in rainbow trout, oncorhynchus mykiss (walbaum).threshold density levels were investigated experimentally in rainbow trout, oncorhynchus mykiss, for the acanthocephalan pomphorhynchus laevis. fifty small fish 120-150 mm long were infected with 50 cystacanths each every 4 weeks for 16 weeks, and samples of up to 10 fish examined at 1, 5, 9, 13 and 17 weeks after the original infection. the mean intestinal length was found to have increased significantly over this period, from a mean of 125 to 173 mm and the mean number of parasites recovered i ...19911866187
ultrastructural observations and radiometric assay on cercarial penetration and migration of the digenean diplostomum spathaceum in the rainbow trout oncorhynchus mykiss.the entrance into host tissues by the cercaria of the digenean diplostomum spathaceum and the parasite's migration to the eyes of the fish host (post-penetration larvae) were studied by scanning and transmission electron microscopy at the ultrastructural level and by a radiometric assay in experimentally infected rainbow trout (oncorhynchus mykiss). it was demonstrated that cercariae penetrated the host surface at several sites, although the major site involved the gill region. this observation ...19911866417
recombinant infectious hematopoietic necrosis virus and viral hemorrhagic septicemia virus glycoprotein epitopes expressed in aeromonas salmonicida induce protective immunity in rainbow trout (oncorhynchus mykiss).fragments of the glycoprotein genes of viral hemorrhagic septicemia virus (vhsv) and infectious hematopoietic necrosis virus (ihnv) were cloned into a bacterial broad-host-range expression vector under the control of the plac promoter. western blot (immunoblot) analysis with monoclonal antibodies specific to the glycoproteins demonstrated the inducible expression of the fusion proteins in escherichia coli. aeromonas salmonicida is the causative agent of furunculosis in salmonid fish. it was conf ...19957486994
the acute effects of alteration in the dietary concentrations of carbohydrate, protein, and lipid on plasma t4, t3, and glucose levels in rainbow trout, oncorhynchus mykiss.the acute (4 hr) postprandial effects of a single isocaloric meal varying in the proportions of either carbohydrate (c)/lipid (l), c/protein (p), or l/p on plasma levels of glucose, t4 (l-thyroxine) and t3 (3,5,3'-triiodo-l-thyronine) were examined in rainbow trout starved for 3 days. relative to starved controls, plasma t3 was generally uninfluenced by feeding but was increased by diets containing the highest c/l and p/l ratios. plasma t4 was elevated only in instances where there was sufficien ...19911879659
osmoregulatory actions of insulin-like growth factor-i in rainbow trout (oncorhynchus mykiss).the ability of insulin-like growth factor-i (igf-i), insulin and gh to promote hypoosmoregulatory ability was examined in juvenile rainbow trout (oncorhynchus mykiss). following adaptation to 12 parts per thousand (p.p.t.) seawater for 5 days, fish were given a single injection of hormone or vehicle, then exposed to 29 p.p.t. for 24 h and examined for changes in plasma osmolarity, ions and glucose. ovine gh (ogh; 0.2 micrograms/g) significantly improved the ability of rainbow trout to maintain p ...19911880479
effects of lindane exposure on rainbow trout (oncorhynchus mykiss) immunity. i. effect of lindane on antibody-secreting cells (asc) measured by elispot assay.yersinia ruckeri vaccine was injected in rainbow trout 7 days after ip contamination with 10, 50, or 100 mg lindane per kilogram body weight. the antibody-secreting cells measured by elispot assay were affected by the insecticide, slightly for 10 mg and strongly for higher concentrations. consequently the antibody production in sera, measured by agglutination, was suppressed.19947525199
comparative toxicity of organotin compounds to rainbow trout (oncorhynchus mykiss) yolk sac fry.the comparative toxicity of various organotin compounds was investigated in early life stages of the rainbow trout. beginning with yolk sac fry, trout were continuously exposed for 110 days to tributyl- (tbtc), triphenyl- (tphtc) or tricyclohexyltin chloride (tchtc) at concentrations of 0.12-15 nm, to trimethyltin chloride (tmtc) at concentrations of 3-75 nm or to dibutyl- (dbtc) or diphenyltin chloride (dphtc) at 160-4000 nm. the diorganotin compounds dbtc and dphtc were about three orders of m ...19911882234
response of xenobiotic metabolizing enzymes of rainbow trout (oncorhynchus mykiss) to the mono-ortho substituted polychlorinated pcb congener 2,3',4,4',5-pentachlorobiphenyl, pcb-118, detected by enzyme activities and immunochemical methods.the mono-ortho-substituted polychlorinated pcb congener 2,3',4,4',5'-pentachlorobiphenyl (pcb-118) was administered i.p. (30 mg/kg body weight) to gonadally immature rainbow trout (oncorhynchus mykiss), of both sexes. in liver microsomes prepared from fish killed 4 days after administration, the cytochrome p450-dependent monooxygenase activities of 7-ethoxyresorufin o-deethylase (erod), aryl hydrocarbon hydroxylase (ahh), and aldrin epoxidase (ae) were measured. in addition, nadph-cytochrome c r ...19911907123
studies on the infectivity of diplostomum spathaceum in rainbow trout (oncorhynchus mykiss).the infectivity of diplostomum spathaceum (digenea: trematoda) cercariae to rainbow trout and the efficacy of the diplostomule migration to the lens following different routes of administration was examined. the optimum age of infectivity for cercariae was between 0-5 h after liberation from the snail and for intraperitoneally injected diplostomules, 5 h post-transformation in vitro through fish skin. after exposure of the entire fish body or head to cercariae, metacercariae first appeared in th ...19911940246
a comparison of hepatic p450 induction in rat and trout (oncorhynchus mykiss): delineation of the site of resistance of fish to phenobarbital-type inducers.1. a comprehensive approach was taken to delineate the site of refractivity of trout to phenobarbital-type (pb-type) hepatic monoxygenase (mo) inducers. 2. model inducers beta-naphthoflavone (bnf; 3-mc-type), and pb as well as the polychlorinated biphenyl isomers, 3,4,5,3',4',5'-hexachlorobiphenyl (3,4,5-hcb; 3-mc-type) and 2,4,5,2',4',5'-hexachlorobiphenyl (2,4,5-hcb; pb-type) were used to assess mo activities, total cytochromes p450, and [35s]-methionine incorporation into de novo synthesized ...19901980437
effects of cortisol on aspects of 3,5,3'-triiodo-l-thyronine metabolism in rainbow trout (oncorhynchus mykiss).aspects of 3,5,3'-triiodo-l-thyronine (t3) metabolism were studied in fed rainbow trout (oncorhynchus mykiss) held at 11.5-14 degrees and intraperitoneally implanted with hydrogenated corn oil (controls) or oil containing cortisol. cortisol implants caused dose-related plasma cortisol elevations within the physiological range for 2-3 weeks, loss in body weight, and depression in plasma t3 and free t3 index with no consistent change in plasma thyroxine (t4) or free t4 index. plasma t3 clearance r ...19912019395
presence of specific growth hormone binding sites in rainbow trout (oncorhynchus mykiss) tissues: characterization of the hepatic receptor.the present work outlines the presence of specific binding for chinook salmon growth hormone (sgh) in different tissue preparations of rainbow trout. optimal incubation conditions (ph, tris, mgcl2) were determined. specific binding was very sensitive to salt concentration during incubation. the specific binding reached a plateau after 15 and 25 hr of incubation at 12 and 4 degrees. at 20 degrees, specific and nonspecific binding were not stable. specific binding dissociation was slower than asso ...19912026319
opsonizing activity of anti-aeromonas salmonicida antibodies after inactivation of complement in rainbow trout.young rainbow trout (oncorhynchus mykiss) were immunized with killed aeromonas salmonicida, bled 5 wk later, and tested for the presence of serum agglutinins. the positive antisera were pooled and fractionated in a ultrogel aca 34 column. seven fractions were collected and concentrated. the higher agglutinin titres were found in the 2nd fraction, which also contained igm revealed by immunoelectrophoresis. the 7 fractions were heated for 30 min at 45 degrees c to inactivate the complement system, ...19912042906
nonspecific cytotoxic cells of rainbow trout (oncorhynchus mykiss) kill yac-1 targets by both necrotic and apoptic mechanisms.nonspecific cytotoxic cells (ncc) have been identified in a number of fish species and are thought to be evolutionary progenitors of mammalian natural killer cells. we show here that trout ncc are functionally similar to cytotoxic cells of higher vertebrates in that they mediate cytotoxicity through both mechanisms of apoptosis and necrosis. to demonstrate that trout ncc inflict apoptic and necrotic lesions in tumor target cells, dna fragmentation and 51chromium release assays were conducted usi ...19912060685
effect of lernaea cyprinacea (crustacea: copepoda) on stocked rainbow trout (oncorhynchus mykiss).prevalence, intensity and pathogenesis of lernaea cyprinacea (anchorworm) in stocked rainbow trout (oncorhynchus mykiss) fingerlings were monitored annually for 4 yr (1981 to 1984) in east canyon reservoir, utah (usa). anchorworms were first detected in midsummer each year and were most abundant in the fall. the mean parasite intensity was highest in october 1982 (19 anchorworms per fish); in other years, maximum density was 7 to 9. the dorsal and caudal areas of the fish were the most heavily p ...19912067042
a conserved aeromonas salmonicida porin provides protective immunity to rainbow trout.a protein with an apparent m(r) of 28,000 was isolated from outer membrane preparations of aeromonas salmonicida a440. the protein was tested for the ability to form pores, using a planar lipid bilayer model membrane system. the protein appeared to be a monomer with a single-channel conductance in 1.0 m kcl of 1.96 ns and a cation/anion permeability ratio of 2.91 +/- 0.68. these data show that the porin channel is comparable in size to ompc and ompf of escherichia coli and is relatively nonselec ...19957622241
monoclonal antibodies to salmonid immunoglobulin: characterization and applicability in immunoassays.monoclonal antibodies to rainbow trout (oncorhynchus mykiss) igm were prepared and characterized for use in immunoassays. antibodies produced by the five clones reacted with the heavy chain of the immunoglobulin. no indication of different heavy chain isotype specificity was observed for the mabs. one clone discerned igm from rainbow trout while the other four clones cross-reacted with igm from atlantic salmon (salmo salar) and from brown trout (salmo trutta). the monoclonal antibodies identifie ...19902086271
carcinogenic and genotoxic activity of extracts from contaminated sediments in western lake order to investigate the putative association between chemical contamination in western lake ontario and high prevalences of fish tumors, sediments from hamilton harbour and oakville creek in lake ontario and reference sites in non-polluted areas of ontario, canada were collected and extracted for organic contaminants. sediment extracts from hamilton harbour had the highest concentrations of polychlorinated biphenyls and organochlorine insecticides (ppb) and contained very high concentrations ...19902163105
a concurrent increasing of natural antibodies and enhancement of resistance to furunculosis in rainbow order to compare the respective roles of specific response and non-specific mechanisms in the enhancement of resistance to furunculosis, 2 groups of rainbow trout (oncorhynchus mykiss) were immunized with supernatants of aeromonas salmonicida or escherichia coli cultures. the fish received 4 weekly intraperitoneal injections (70 micrograms of crude proteins). one control group was injected with phosphate-buffered saline, while another was untreated. specific agglutinins were produced only in ...19902202250
the laboratory maintenance of diphyllobothrium dendriticum (nitzsch, 1824).a protocol for the routine laboratory maintenance of the life-cycle of diphyllobothrium dendriticum, using herring gulls (larus argentatus), cyclops abyssorum and rainbow trout oncorhynchus mykiss ( = salmo gairdneri) as the definitive, first and second intermediate hosts respectively, is described.19902235071
influence of dietary lipid and carbohydrate levels and chronic 3,5,3'-triiodo-l-thyronine treatment on thyroid function in immature rainbow trout, oncorhynchus mykiss.the influence of varying dietary levels of nonprotein energy sources (lipid, l; carbohydrate, c) and 3,5,3'-triiodo-l-thyronine (t3) on thyroid function in immature rainbow trout was studied. three diets of equivalent available energy content and identical nutrient composition, except for dissimilar concentrations of l and c (diet 1, l = 7%, c = 28.3%; diet 2, l = 13%, c = 14.9%; diet 3, l = 19%, c = 1.5%), were each supplemented with 0, 4, 8, or 12 ppm t3 and fed to satiation to trout at 6.5 +/ ...19902272475
a radioimmunoassay for perch (perca fluviatilis) metallothionein.a sensitive radioimmunoassay (ria) for the measurement of metallothionein (mt) from perch (perca fluviatilis) has been developed. the method is a double-antibody ria with rabbit anti-perch mt serum as first antibody, goat anti-rabbit immunoglobulin g as second antibody, and perch mt conjugated to 125i-labeled bolton-hunter reagent as tracer. the rabbit antiserum raised against perch mt recognizes rainbow trout (oncorhynchus mykiss) mt, but shows little cross-reactivity with horse mt. at a diluti ...19902315933
vascular reactivity of the coronary artery in rainbow trout (oncorhynchus mykiss).vascular reactivity of the large coronary artery of a lower vertebrate was investigated for the first time in this study. the responses of vascular rings to various pharmacological agents were measured using isometric force transducers. coronary arteries from rainbow trout, oncorhynchus mykiss, contracted with acetylcholine and predominantly relaxed with isoproterenol, epinephrine, norepinephrine, and serotonin. atenolol blocked the adrenergic relaxation, suggesting a predominance of beta 1-adre ...19902360689
effects of ichthyophonus hoferi on condition indices and blood chemistry of experimentally infected rainbow trout (oncorhynchus mykiss).body condition, hepatosomatic index and blood chemistry of oncorhynchus mykiss experimentally infected with a tissue dwelling fish pathogenic fungus, ichthyophonus hoferi, were monitored over a 6 wk period. this was to determine whether the infection constituted a stress manifest by changes in the hypothalamic-pituitary interrenal axis, and especially plasma cortisol levels. infection caused anaemia and leucopenia but did not change the condition, hepatosomatic indices, or plasma chloride, chole ...19902388355
phenotypic and genomic studies of "cytophaga psychrophila" isolated from diseased rainbow trout (oncorhynchus mykiss) in france.five strains of gliding bacteria were isolated in france from farmed diseased rainbow trouts reared at low water temperature. the resemblance of these bacteria to the known fish pathogen "cytophaga psychrophila" led to their comparative study with reference strain ncmb 1947 and with an american isolate. morphological, physiological, and biochemical characteristics of the seven strains proved to be similar. comparison of their dna by the s1 nuclease dna-dna hybridization method showed that the se ...19892764577
[a study of the cause of massive mortality among marine-cultured rainbow trout (oncorrhynchus mykiss, walbaum) in a fish farm in the southwestern netherlands].the present study investigated the mass mortality of marine cultured young rainbow trout (oncorhynchus mykiss, walbaum) in the netherlands. the course of the disease, the clinical symptoms, and bacteriological and virological investigations lead to the diagnosis: 'primary infectious pancreatic necrosis virus (ipnv) infection followed by secondary vibriosis'. treatment with flumequine seemed to be effective. the trout were possible infected with ipnv at the trout hatchery and nursery from which t ...19957482471
[food habits of the rainbow trout oncorhynchus mykiss (salmoniformes: salmonidae) in an andean creek of venezuela].monthly stomach context samples of rainbow trout from mucunután stream (mérida, venezuela), were collected from, march 1987 to february 1988 (n = 306). the major dietary components were ephemeroptera, trichoptera and diptera. baetodes sp. was the most important food item based on numerical composition (43%) and frequency of occurrence (88%). when the gravimetric method was used leptonema sp. was the major dietary component. the diet was not a function of sex. the consumed fauna was more similar ...19947501873
parasite infections in danish trout farms.samples from 5 danish freshwater trout farms rearing rainbow trout (oncorhynchus mykiss) were examined for parasite infections from october 1993 until november 1994 and recorded parasites are listed. in addition, results from an examination of a mariculture net cage system are presented as well. a total of 10 metazoan and 10 protozoan parasites were recorded. the metazoans included gyrodactylus derjavini, gyrodactylus salaris, eubothrium crassum, triaenophorus nodulosus, proteocephalus sp., dipl ...19957502946
cadmium toxicity to rainbow trout oncorhynchus mykiss walbaum and brown trout salmo trutta l. over extended exposure periods.the toxicity of cadmium in water is well known, but there have been few reports on the long-term effects of this metal on fish at concentrations near the european inland water standard of 5 micrograms cd liter-1. this paper describes experiments in which adult rainbow trout oncorhynchus mykiss and brown trout salmo trutta were exposed to cadmium concentrations near water quality standard levels for periods of up to 90 weeks. the survival and growth of these fish were assessed, and sperm and eggs ...19947529162
stimulation of in vitro ovarian estradiol-17 beta synthesis in the rainbow trout by the carbohydrate-poor protein fraction from sockeye salmon pituitary glands.the role of carbohydrate-poor (con a i) and carbohydrate-rich (con a ii) pituitary protein fractions, isolated from sockeye salmon (oncorhynchus nerka), were investigated pertaining to in vitro estradiol-17 beta (e2) production by rainbow trout (oncorhynchus mykiss) ovarian follicles. during the early vitellogenic phase of the reproductive cycle, using defolliculated ovarian follicle preparations (outer epithelium-thecal layer absent), it was demonstrated that the con a i fraction was capable of ...19911911440
measurement and prediction of digestible energy values in feedstuffs for the herbivorous fish tilapia (oreochromis niloticus linn.).digestible energy (de) values were measured in a selection of feedstuffs for the tilapia (oreochromis niloticus linn.) and used to develop equations for predicting de values of a wider range of feedstuffs from chemical analyses. preliminary work examined the influences of substitution level in a reference diet and adaptation over time on de values for soya-bean meal. length of adaptation period significantly affected de values (p less than 0.01), but substitution level, over the range 200-600 g ...19911931904
characterization of epidermal growth factor binding to hepatic plasma membranes of rainbow trout (oncorhynchus mykiss).epidermal growth factor (egf) is a potent mitogen which exerts its effects through a transmembrane receptor located on target cells. since little is known about egf in nonmammalian animals, experiments were conducted to characterize the egf receptor in rainbow trout hepatic cell membranes. the binding of mouse egf with rainbow trout receptors was peptide-specific, saturable, reversible, and of high affinity. optimal binding was observed at ph 7.2. both monovalent and divalent cations augmented t ...19911936915
hplc determination of plasma thiocyanate concentrations in fish blood: application to laboratory pharmacokinetic and field-monitoring studies.the pharmacokinetics of thiocyanate (scn-) in the blood plasma of 35-g rainbow trout (oncorhynchus mykiss) were followed during a 20-day exposure to 39.8 mg scn- liter-1 and the subsequent 16-day depuration period. scn- concentrations were determined by reverse-phase hplc. kinetic constants were estimated using a one-compartment first-order kinetic model fitted to the data by the computer programs biofac and systat. the respective biofac and systat estimates for the uptake rate constant (k1, 0.5 ...19957541344
[characterization of cdna of t-cell receptor beta chain in rainbow trout].using a two-step pcr strategy, we have cloned several cdna segments encoding the t-cell receptor beta chain in a teleost fish, the rainbow trout (oncorhynchus mykiss). the nine clones analyzed encode identical n-terminal-truncated v beta regions which present limited sequence similarities with several mammalian tcr v beta chains, from residue tyr-35 to residue ser-95. these v beta regions are followed by v beta-d beta-j beta-like regions which are different in all the sequenced clones, and by id ...19947882160
effects of transforming growth factor beta 1 on rainbow trout oncorhynchus mykiss macrophage respiratory burst activity.natural bovine transforming growth factor beta 1 (tgf-beta 1) was found to have both enhancing and suppressing effects on the respiratory burst activity of rainbow trout, oncorhynchus mykiss, head kidney macrophages. incubation with tgf-beta 1 alone increased respiratory burst activity using doses from 0.05 to 0.2 ng/ml. however, incubation of activated macrophages with tgf-beta 1 decreased their respiratory burst activity in a dose-dependent manner. coincubation of macrophages with activating s ...19947883061
rainbow trout ventricular natriuretic peptide: isolation, sequencing, and determination of biological activity.ventricular natriuretic peptide (vnp) is a new type of cardiac natriuretic peptide initially isolated from the eel ventricle. vnp has been isolated from cardiac ventricles of the rainbow trout, oncorhynchus mykiss, and found to consist of 35 amino acid residues carrying a c-terminal tail sequence with 14 amino acid residues. thus, the long c-terminal sequence characteristic of vnp was also conserved in the trout vnp. a vnp with 4 amino acid residues truncated from the c-terminus was also isolate ...19947883149
glucose dehydrogenase in beef (bos taurus) and rainbow trout (oncorhynchus mykiss) liver: a comparative study.the monomer molecular mass of glucose dehydrogenase (gdh, ec from rainbow trout liver and beef liver were estimated to be 90 kda for both enzymes, by electrophoresis in the presence of na-dodecyl-so4 (sds). the 90-kda proteins were partially degraded to about 60 kda when purified with a delayed procedure without protease inhibitors. tryptic cleavage of the 90-kda proteins gave fragments of about 60 kda and 30 kda, being similar for trout and beef gdh. isoelectric points, kinetic and th ...19947553351
immunoregulatory activities of eicosanoids in the rainbow trout (oncorhynchus mykiss).eicosanoids such as prostaglandins (pg), leukotrienes (lt) and lipoxins (lx) have been shown to be potent immunoregulatory molecules in mammals. to determine if they have similar roles in 'lower' animals, rainbow trout (oncorhynchus mykiss) were immunized with either sheep erythrocytes or aeromonas salmonicida in the presence or absence of the stable analogue of pge2, 16,16-dimethyl-pge2, and the number of plaque-forming cells (pfc) or specific antibody levels determined. the higher dose of 16,1 ...19957558126
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