dna content in eurasian sturgeon species determined by flow cytometry.the nuclear dna content in 10 species of chondrostean fishes was measured by flow cytometry. the sterlet acipenser ruthenus blood cells were used as an internal standard. the sterlet dna content was calculated on the basis of comparison with the xenopus laevis blood cells, 2c = 6.30 pg. in the tetraploid a. ruthenus and a. stellatus the dna content comprises 3.74 pg/nucleus and is practically invariant; in huso dauricus it is almost the same, 3.74-3.81 pg; and in a. nudiventris it is a little hi ...19938513694
[nontraditional "large-cell" neuroendocrine formations (accessory nuclei) in the brain of anamnia and amniota].using immunochemical pap-method nonapeptidergic neuroendocrine formations in the hypothalamus and adjacent brain areas of fishes (the sterlet acipenser ruthenus, the shark scylliorhinus canicula), amphibians (the frog rana temporaria), reptiles (the snake natrix natrix), mammals (rats and dogs) and human have been studied. in amniota and human accessory nuclei (an) in addition to main "magnocellular" nuclei (supraoptic, postoptic and paraventricular) were discovered. two an, circular and dorsola ...19958714298
chromosomal mapping of 18s-28s and 5s rrna genes by two-colour fluorescent in situ hybridization in six sturgeon species.the number and distribution of the 18s-28s and 5s rrna (rdna) gene sequences were examined on mitotic chromosomes of six sturgeon species by two-colour in situ hybridization. four of the six species, huso huso, acipenser stellatus, acipenser sturio, and acipenser ruthenus, with about 120 chromosomes, showed from six to eight 18s-28s rdna signals, while 5s rdna signals were on only one chromosome pair. the two species with 250-270 chromosomes, acipenser baerii and acipenser transmontanus, showed ...200312834065
Lactococcus lactis subsp. lactis infection in Bester sturgeon, a cultured hybrid of Huso huso×Acipenser ruthenus, in Taiwan.Approximately 5300 hybrid sturgeons with an average body weight of 600-800g were farmed in 3 round tankers measuring 3m in diameter each containing 28,000L of aerated groundwater. According to the owner's description, the diseased fish had anorexia, pale body color, and reddish spots on the abdomen. The morbidity and lethality rates in this outbreak were about 70% (3706/5300) and 100% (3706/3706), respectively. The clinical examination revealed enteritis, enlarged abdomen, and rapid respiration ...201122098776
3-d structure, volume, and dna content of erythrocyte nuclei of polyploid fish.we have explored the potential relationship between ploidy level, dna content (pg dna nucleus(-1)), and dimensional characteristics, such as volume (μm(3)), surface area (μm(2)), and 3-d structure of erythrocyte nuclei in a series of fish ploidy level models using feulgen image analysis densitometry, flow cytometry, and confocal laser scanning microscopy. the species were diploid tench (tinca tinca) (2n), cuban gar (atractosteus tristoechus) (2n), triploid tench (3n), evolutionary tetraploid ste ...201424446105
[ultrastructural characteristics of the vitellaria, uterus and vagina of amphilina foliacea rudolphi, 1819 (cestoda: amphilinidea)].the ultrastructural features of the vitelline follicles, uterus and vagina of the amphilinid cestode amphilina foliacea from the body cavity of acipenser ruthenus of the volga basin are described. some new distinguishing characters are revealed, including the presence of a single type of the cellular component in the vitelline follicles with sarcoplasmic processes filling the space around and within vitellocytes. the,uterus of this species is recognized by the presence of the syncytial epithelia ...201425464739
[ultrastructural characteristics of the vitellaria, uterus and vagina of amphilina foliacea rudolphi, 1819 (cestoda: amphilinidea)].the ultrastructural features of the vitelline follicles, uterus and vagina of the amphilinid cestode amphilina foliacea from the body cavity of acipenser ruthenus of the volga basin are described. some new distinguishing characters are revealed, including the presence of a single type of the cellular component in the vitelline follicles with sarcoplasmic processes filling the space around and within vitellocytes. the,uterus of this species is recognized by the presence of the syncytial epithelia ...201425508370
non-dioxin-like pcbs in ten different fish species from the danube river in serbia.this work has been developed to examine the level of non-dioxin-like (ndl) pcbs (28, 52, 101, 138, 153 and 180) in (a) ten different freshwater fish species from the danube river, (b) two sampling points: up and downstream of the industrial zone of the city of pancevo (ecological hot spot in serbia) and (c) two time points i.e., in 2001 and 2006. obtained results would serve to analyse spatial, temporal and congener profile characteristics of ndl pcbs cumulated in fish tissues due to environment ...201021161586
detection of mycobacteria in aquarium fish in slovenia by culture and molecular methods.thirty-five aquarium fish were investigated for the presence of mycobacteria by culture and molecular methods. the following species were examined: goldfish carassius auratus auratus, guppy poecilia reticulata, 4 three-spot gourami trichogaster trichopterus, dwarf gourami colisa lalia, siamese fighting fish betta splendens, freshwater angelfish pterophyllum scalare, african cichlid fish cichlidae spp., cichlid fish microgeophagus altispinosus, cichlid fish pseudotropheus lombardoi, blue streak h ...200515900685
[polypodium hydriforme in the eggs of the sterlet from the northern dvina river].the paper provides data on the invasion of acipenser ruthenus (sterlet) in the north dvina river by polypodium hydriforme (cnidaria). prevalence and intensity of invasion proved to be similar for two fishing sites. prevalence of invasion exceeded 88%, thus being exceptionally high for p. hydriforme. intensity of invasion was from 1 to 436 eggs per female. a verage percentage of infected eggs was about 1%.200312815815
the genus acipenser as a model system for vertebrate urogenital development: nephrostomial tubules and their significance for the origin of the gonad.early gonadal development was studied in the sterlet, acipenser ruthenus, by means of histological and semithin serial sections and scanning electron microscopy. special attention was given to the role of opisthonephric nephrostomial tubules and their coelomic funnels (nephrostomes, coelomostomes) in the origin of the gonad. specimens of about 1 mm in length (about 7 days post hatching) have a continuous kidney complex (holonephros) that extends from the branchial region to the level of the cloa ...200211875667
cd3epsilon homologues in the chondrostean fish acipenser ruthenus.cd3epsilon is an essential component of the t-cell receptor (tcr) complex for antigen. we report here molecular cloning and characterization of cdnas encoding the cd3epsilon homologues in sterlet (acipenser ruthenus), a representative of primitive chondrostean fishes. sequence analysis of the cdna clones demonstrated unexpectedly high cd3epsilon gene heterogeneity in this species. while some cdnas encoded proteins with the structure typical of mammalian cd3epsilon, others coded for proteins lack ...200011061286
effects of temperature on in vitro short-term storage of sterlet sturgeon (acipenser ruthenus) ova.artificial propagation of sturgeons is becoming increasingly important for recovery efforts as well as for commercial production. sterlet acipenser ruthenus is a common eurasian sturgeon with a small body size and one of the fastest reproductive cycles among the sturgeons. the practical question being addressed in this study was how long fertilization of ovulated eggs can be delayed without substantially reducing the hatching rate, and an ancillary question is under what' temperature conditions ...201626708725
segmental paleotetraploidy revealed in sterlet (acipenser ruthenus) genome by chromosome painting.acipenseriformes take a basal position among actinopteri and demonstrate a striking ploidy variation among species. the sterlet (acipenser ruthenus, linnaeus, 1758; arut) is a diploid 120-chromosomal sturgeon distributed in eurasian rivers from danube to enisey. despite a high commercial value and a rapid population decline in the wild, many genomic characteristics of sterlet (as well as many other sturgeon species) have not been studied.201526587056
the antioxidant system of seminal fluid during in vitro storage of sterlet acipenser ruthenus sperm.the role of the seminal fluid antioxidant system in protection against damage to spermatozoa during in vitro sperm storage is unclear. this study investigated the effect of in vitro storage of sterlet acipenser ruthenus spermatozoa together with seminal fluid for 36 h at 4 °c on spermatozoon motility rate and curvilinear velocity, thiobarbituric acid reactive substance level, and components of enzyme and non-enzyme antioxidant system (superoxide dismutase and catalase activity and uric acid conc ...201626559692
enzyme activity in energy supply of spermatozoon motility in two taxonomically distant fish species (sterlet acipenser ruthenus, acipenseriformes and common carp cyprinus carpio, cypriniformes).as spermatozoon motility duration differs significantly among fish species, the mechanism of atp generation-regeneration and its distribution along the flagellum may be species-dependent. the present study compared the role of creatine kinase (ck) with that of adenylate kinase (ak) in atp regeneration during motility of demembranated spermatozoa of taxonomically distant fish species, sterlet, and common carp, allowing investigation for the presence of the creatine-phosphocreatine (pcr) shuttle i ...201626483312
comparative localization of corticotropin and corticotropin releasing factor-like peptides in the brain and hypophysis of a primitive vertebrate, the sturgeon acipenser ruthenus l.the sturgeon is a primitive actinopterigian fish that, unlike modern teleosts, possess a portal vascular system that connects a true median eminence with the anterior pituitary as in mammals. the occurrence and localization of corticotropin and corticotropin releasing factor-like immunoreactivies were examined in the brain of the sturgeon (acipenser ruthenus l.) by immunocytochemistry with antisera raised against synthetic non-conjugated human corticotropin, and rat/human corticotropin releasing ...19921335041
the parasitic coelenterate, polypodium hydriforme ussov, from the eggs of the american acipenseriform polyodon significant differences in macro- and micromorphology were found between the parasitic stolon and free-living polyps of polypodium sp. obtained from infected eggs of the north american acipenseriform fish polyodon spathula and corresponding developmental stages of polypodium hydriforme ussov, parasitic in the volga sterlet (acipenser ruthenus). therefore, both the american and the european forms of polypodium belong to the species p. hydriforme ussov.197941895
the mammalian skeletal muscle dhpr has larger ca(2+) conductance and is phylogenetically ancient to the early ray-finned fish sterlet (acipenser ruthenus).the l-type ca(2+) channel or dihydropyridine receptor (dhpr) in vertebrate skeletal muscle is responsible for sensing sarcolemmal depolarizations and transducing this signal to the sarcoplasmic ca(2+) release channel ryr1 via conformational coupling to initiate muscle contraction. during this excitation-contraction (ec) coupling process there is a slow ca(2+) current through the mammalian dhpr which is fully missing in euteleost fishes. in contrast to ancestral evolutionary stages where skeletal ...201727793347
the influence of cryoprotectants on sturgeon (acipenser ruthenus) sperm quality, dna integrity, antioxidant responses, and resistance to oxidative stress.this study examined the effect of cryoprotectants on dna integrity, antioxidant defense, and resistance to oxidative stress in cryopreserved sterlet acipenser ruthenus sperm. the freeze-thaw process significantly influenced sperm motility, with significant differences among cryoprotectants. in vitro exposure of cryopreserved sperm to the xanthine-xanthine oxidase (x-xo) system as a model reactive oxygen species inducer resulted in a lesser motility rate and velocity compared to the control, and ...201526089085
bioaccumulation of heavy metals and microelements in silver bream (brama brama l.), northern pike (esox lucius l.), sterlet (acipenser ruthenus l.), and common carp (cyprinus carpio l.) from tisza river, serbia.the aim of this study was to determine the concentrations of al, as, b, cd, co, cr, cu, fe, hg, mn, ni, pb, se, sr, and zn in liver, gills, gonads, and brain of four ecologically different fish species in serbia: piscivorous northern pike, benthivorous sterlet and silver bream, and omnivorous common carp. fish were caught at four sites along the stretch of the river tisza in the pannonian part of serbia during october 2010. results revealed that heavy metals and microelements with the highest va ...201526039743
activation of the albino sterlet acipenser ruthenus eggs by uv-irradiated bester hybrid spermatozoa to provide gynogenetic progeny.meiotic gynogenesis was induced in the albino form of sterlet acipenser ruthenus by activation of eggs with uv-irradiated bester (huso huso x acipenser ruthenus) spermatozoa followed by inhibition of the second meiotic division performed by a heat shock. obtained putative gynogenetic progeny were all albinos. the genetic verification based on three microsatellite dna markers confirmed the only maternal inheritance of the progeny from the gynogenetic experimental groups. cytogenetic analysis prov ...201525858073
ultrastructural localization of intracellular calcium during spermatogenesis of sterlet (acipenser ruthenus).calcium regulates many intracellular events such as growth and differentiation during different stages of gamete development. the aim of this study was to localize and quantify the intracellular distribution of calcium during different developmental stages of spermatogenesis in sterlet, acipenser ruthenus, using a combined oxalate-pyroantimonate technique. the distribution of calcium was described in spermatogonium, spermatocyte, spermatid, and spermatozoon stages. in the spermatogonium and sper ...201627866505
gonad histology and serum 11-kt profile during the annual reproductive cycle in sterlet sturgeon adult males, acipenser ruthenus.the aim of this study was to assess monthly testicular development in the cultured breeding stock of sterlet, acipenser ruthenus, using histological and serum sex steroid changes. testicular development in the adult male was examined monthly and showed four distinct phases including resting, pre-spawning, spawning and post-spawning. also, seasonal changes of the testes were described according to its variations in gonadosomatic index (gsi) during different phases of testicular development. using ...201728109018
physiological changes and reproductive performance of sterlet sturgeon acipenser ruthenus injected with evaluate the effects of thiamine on physiological changes and spawning performance of sterlet sturgeon acipenser ruthenus, 45 farmed female fish (698.6±8.9g) were randomly distributed in 9 tanks (1000l) and fed a diet with 1g/kg of an anti-thiamine drug. this was provided for 5 months prior to spawning. thiamine hydrochloride was intraperitoneally injected to fish at three different doses: 0 (t0, as control), 5 (t5) and 50 (t50) mg/kg body weight at days 30, 90 and 150 after the experiment st ...201728131605
disturbances in the ploidy level in the gynogenetic sterlet acipenser ruthenus.artificial mitotic gynogenesis, a chromosome set manipulation, is applied to provide the homozygous progeny with only maternal inheritance. here, gynogenetic development was induced in the sterlet acipenser ruthenus l. (acipenseridae) by activation of the eggs originating from albino females with the uv-irradiated spermatozoa from wild-coloured males, followed by the heat shock applied to suppress the first mitotic division in the haploid zygotes. all experimentally obtained gynogenetic offsprin ...201728168627
ig light chain gene in the siberian sturgeon (acipenser baeri).elasmobranch and teleost fish have their ig light (l) chain loci organized in multiple clusters (vl-jl-cl). the vl segments of teleosts are in opposite transcriptional orientation to the cl genes, suggesting that in teleosts and elasmobranchs there may have been separate evolutionary events leading to this organization. to address this problem, the igl locus from the siberian sturgeon (acipenser baeri) (representative of a branch between elasmobranchs and teleosts) was investigated. sequence ana ...19968757324
early development of the olfactory organ in sturgeons of the genus acipenser: a comparative and electron microscopic study.formation and morphology of the olfactory organ of vertebrates has been intensely studied in some taxa for more than a century. as a functionally important and complex sensory organ, its ontogenetic development has often been a matter of debate on higher-level craniate evolution. however, sufficient knowledge of structure and development of the olfactory organ in the crucial taxa needed for a serious phylogenetic reasoning is generally not available. this study aims at this essential primary dat ...200312684762
cloning hsp70 and hsp90 genes of kaluga (huso dauricus) and the effects of temperature and salinity stress on their gene expression.the genes encoding hsp70 and hsp90 proteins were isolated from kaluga by homologous cloning and rapid amplification of complementary dna (cdna) ends (race). hsp70 (genbank accession no. kp050541) and hsp90 (genbank accession no. kp050542) cdnas were composed of 2275 and 2718 bp and encoded polypeptides of 650 and 725 amino acids, respectively. basic local alignment search tool (blast) analysis showed that hsp70 and hsp90 of kaluga shared high identities with those of acipenser ruthenus, acipense ...201626683614
cryopreservation of early stage siberian sturgeon acipenser baerii germ cells, comparison of whole tissue and dissociated cells.several sturgeon species are near extinction; therefore an efficient conservation strategy is required. germ stem cells can be used for long-term storage and restoration of genetic information using surrogate reproduction. this study compared cryopreservation procedures of early stages of siberian sturgeon acipenser baerii testicular and ovarian cells. whole gonad tissue or dissociated cells were frozen at a cooling rate of 1 °c/min in phosphate buffered saline with 0.5% bovine serum albumin, 50 ...201626920821
fertilization success of sterlet acipenser ruthenus and siberian sturgeon acipenser baerii gametes under conditions of heterospecific mating.species may be prevented from interspecific hybridization by a number of different reproductive barriers that operate precopulatory and postcopulatory. in situation, when natural precopulatory reproductive barriers are affected by anthropogenic factors, postcopulatory reproductive barriers may be important for maintaining gametic isolation and hence preventing interspecific hybridization. this is highly topical in sturgeon (order acipenseriformes) which exhibits remarkable ease of interspecific ...201627692499
effects of feeding, digestion and fasting on the respiration and swimming capability of juvenile sterlet sturgeon (acipenser ruthenus, linnaeus 1758).the objective of this study is to provide information on changes in swimming capability and respiration of the sterlet sturgeon (acipenser ruthenus, linnaeus 1758) caused by different levels of fasting. before testing, the four groups of sturgeon (body length: 12.1-15.4 cm, body mass: 10.0-20.2 g) fasted for 6 h, 2 days, 1 and 2 weeks, respectively. swimming tests were then performed to measure critical swimming speed and oxygen consumption at 20 ± 0.5 °c. results show: (1) fasting times shorter ...201727632015
different computer-assisted sperm analysis (casa) systems highly influence sperm motility this study, we examined different computer-assisted sperm analysis (casa) systems (crismas, hobson sperm tracker, and image j casa) on the exact same video recordings to evaluate the differences in sperm motility parameters related to the specific casa used. to cover a wide range of sperm motility parameters, we chose 12-second video recordings at 25 and 50 hz frame rates after sperm motility activation using three taxonomically distinct fish species (sterlet: acipenser ruthenus l.; common ca ...201323932168
[determination of 17 amino acids in fish eggs by ultra performance liquid chromatography coupled with precolumn derivatization].a rapid quantitative method of ultra performance liquid chromatography (uplc) has been developed for the analysis of 17 amino acids in fish eggs from acipenser schrenckii, huso dauricus and acipenser ruthenus. the analytes were hydrolyzed with 6 0 mol/l hci. the extraction solution was concentrated under low pressure and neutralized with naoh solution before derivatization with 6-aminoquinolyl-n-hydroxy-succinimidyl carbamate (aqc) as derivatization agent in borate buffer solution (ph 8.8). grad ...201323786002
role of ca2+ in the ivm of spermatozoa from the sterlet acipenser ruthenus.the role of ca2+ in sturgeon sperm maturation and motility was investigated. sperm from mature male sterlets (acipenser ruthenus) were collected from the wolffian duct and testis 24 h after hormone induction. testicular spermatozoa (ts) were incubated in wolffian duct seminal fluid (wdsf) for 5 min at 20°c and were designated 'ts after ivm' (tsm). sperm motility was activated in media with different ion compositions, with motility parameters analysed from standard video microscopy records. to in ...201627246727
[the effect of hormonal stimulation of sterlet (acipenser ruthenus l.) on steroid levels in tissue incubates].sex steroids and corticol levels in leibovitz's l-15 media samples after incubation of intact female and male sterlet (acipenser rhutenus l.) tissue fragments and those if fishes treated with a superactive analogue of mammalian luteinising hormone-releasing hormone (lh-rh-a) were compared. 17,20β,21-trihydroxy-4-pregnen-3-one (20βs) levels were significantly higher in the media samples after incubation of ovarian follicles taken from females 5 h after treatment with lh-rh-a in comparison with 20 ...201627220236
a method for hypophysectomy of the sexually mature sterlet, acipenser ruthenus l., and the state of the fish after the operation.hypophysectomy was performed on sexually mature sterlets, acipenser ruthenus l., in summer and autumn. the operation usually lasted about 45 sec, but never longer than 90 sec. after the parasphenoid was stripped, an ellipsoid hole was trepanated at the level of the eyes. the hypophysis was ablated by catching its rostral end with a pincer. as the result of the extirpation of the hypophysis the majority of the specimens grew steadily lighter, and a considerable loss of the body weight as well as ...20144076766
erratum to: changes of vitellogenin and lipase in captive sterlet sturgeon acipenser ruthenus females during previtellogenesis to early atresia. 201627052423
motility initiation of sterlet sturgeon (acipenser ruthenus) spermatozoa: describing the propagation of the first flagellar the present study, for the first time in fish spermatozoa, we describe the precise chronology of motility initiation of sterlet (sturgeon) sperm from completely immotile flagella to regular full wave propagation. the successive activation steps were investigated by high-speed video microscopy, using specific experimental situation, where sperm motility initiation was delayed in time up to several seconds (10 ± 2.68 seconds). starting from fully immotile, the flagellum shows some trembling for ...201525794841
[the origin and possible role of microvesicles in olfactory receptor cells].microvesicles and spherical particles have been described in the bulbs of receptor olfactory cells of acipenser ruthenus. two pathways of the origin of the above vesicles have been followed. these structures derive at the stage of differentiation from non-ciliary to ciliary cell type. the first of the pathways involves the autolysis of microfibril bundles produced during the regression of microvilli. the other one includes micropinocytosis induced on the basis of regressing microvilli. taking in ...20051231094
effects of dietary garlic powder on growth, feed utilization and whole body composition changes in fingerling sterlet sturgeon, acipenser ruthenus.a 12 week growth study was carried out to investigate the supplemental effects of dietary garlic powder (gp) on growth, feed utilization and whole body composition changes of fingerling sterlet sturgeon acipenser ruthenus (averaging weight, 5.5 g). following a 24-h fasting, 540 fish were randomly distributed to each of 18 tanks (30 fish/tank) under a semi-recirculation freshwater system. the gp of 0.5% (gp0.5), 1% (gp1), 1.5% (gp1.5), 2% (gp2) and 3% (gp3) was added to the control diet (gp0) con ...201425178374
commercial fish species of inland waters: a model for sustainability assessment and management.the permanent increase in the exploitation of commercial fish species has led to the need for developing practical and effective tools for the sustainability assessment and management of the target fish populations. the aim of this study was to formulate an eshippofishing model which would provide a reliable assessment of commercial fish population sustainability and indicate the conservation priorities. the existing eshippo model was modified by introducing a new index of local sustainability o ...201425170830
motility and fertilization ability of sterlet acipenser ruthenus testicular sperm after cryopreservation.sturgeon spermatozoa are immotile in the testis and acquire the potential for motility after contact with urine in wolffian duct. the present study tested if in vitro incubation of testicular sperm in seminal fluid from wolffian duct sperm leads to the acquisition of sperm fertilization ability. sterlet sperm was taken from the testes, matured in vitro and cryopreserved. the fertility and motility of cryopreserved semen were tested. matured testicular sperm showed freeze-thaw survival rates simi ...201425058859
in vitro sperm maturation in sterlet, acipenser ruthenus.the aim of the study was to examine sperm maturation in sturgeon and to establish the localization of the maturation. we demonstrated that sperm maturation occurs in sturgeon outside the testes via dilution of sperm by urine. the process involves the participation of high molecular weight (>10kda) substances and calcium ions.201424856476
biochemical characterisation and assessment of fibril-forming ability of collagens extracted from bester sturgeon huso huso × acipenser ruthenus.collagens purified from bester sturgeon organs were characterised biochemically, and their fibril-forming abilities and fibril morphologies formed in vitro clarified. yields of collagens were 2.1%, 11.9%, 0.4%, 18.1%, 0.4%, 0.8% and 0.03% (collagen dry weight/tissue wet weight) from scales, skin, muscle, swim bladder, digestive tract, notochord and snout cartilage, respectively. using sds-page and amino acid composition analyses, collagens from scales, skin, muscle, the swim bladder and digestiv ...201424799243
evidence for a divergence in function between two glucocorticoid receptors from a basal teleost.duplicated glucocorticoid receptors (gr) are present in most teleost fish. the evolutionary advantage of retaining two grs is unclear, as no subtype specific functional traits or physiological roles have been defined. to identify factors driving the retention of duplicate grs in teleosts, the current study examined grs in representatives of two basal ray-finned fish taxa that emerged either side of the teleost lineage whole genome duplication event (wgd) event, the acipenseriform, acipenser ruth ...201222862956
comparison of protein fractions in seminal plasma from multiple sperm collections in sterlet (acipenser ruthenus).seminal plasma of sterlet acipenser ruthenus was evaluated using comparative proteomics to characterize its protein fractions and to determine any influence of multiple sperm collections on these proteins. an experimental group of fish was used, in which sperm was collected three times at 5 h intervals. protein fractions of seminal plasma were determined by sds-gel electrophoresis (sds-page) and two-dimensional electrophoresis high-resolution gels (2d). at all stripping times, five protein bands ...201322747924
sperm characteristics and androgens in acipenser ruthenus after induction of spermiation by carp pituitary extract or gnrha implants.spermiation and changes in androgen (testosterone, t and 11-ketotestosterone, 11-kt) levels were studied in sterlet (acipenser ruthenus) treated with gnrh agonist implants (dala(6)-pro(9)-lhrha) at 25 and 75 μg kg(-1) b.w. and compared with those males treated with 4 mg kg(-1) b.w. of carp pituitary extract (cpe) and 3 pellets of ovopel kg(-1) b.w., which contains dala(6)-pro(9)net-mgnrh and metoclopramide. sperm quality (sperm mass, spermatozoa concentration and sperm motility and velocity) was ...201222665160
use of histopathology and elemental accumulation in different organs of two benthophagous fish species as indicators of river pollution.the bottom feeding fish species have a good potential to be used for assessments of pollution, as they are under pressure from pollutants from both water and sediments. in this study, the level of similarity of histopathological responses to pollution in gills and liver between barbel (barbus barbus) and sterlet (acipenser ruthenus) from the danube river was assessed, and compared with elemental concentrations in their gills, liver, and muscle. results indicate that the detected metal concentrat ...201524677754
protease in sturgeon sperm and the effects of protease inhibitors on sperm motility and mammals, proteases are present in sperm acrosome and play key role in fertilization. sturgeon sperm has an acrosome, but its physiology, biochemistry, and potential role in fertilization are unknown. in the present study, we have observed high protease activity in acidic extract of intact sperm compared to that of seminal plasma in sterlet (acipenser ruthenus). the protease activity was decreased and increased in acidic extract of motility-activated sperm and in the activation medium, respect ...201424677048
effects of tetrabrombisphenol a on dna integrity, oxidative stress, and sterlet (acipenser ruthenus) spermatozoa quality variables.the sperm of sterlet (acispenser ruthenus) was used to investigate the effect of the xenobiotic tetrabrombisphenol a (tbbpa) on sperm quality variables (atp content, spermatozoa motility, and velocity), dna integrity, and oxidative stress indices. sperm was diluted to obtain a spermatozoa density of 5 × 10(8) cells/ml and exposed for 2 h to final concentrations of tbbpa (0.5, 1.75, 2.5, 5, and 10 μg/l). the oxidative stress indices, including lipid peroxidation, carbonyl derivatives of proteins, ...201524459015
complete mitochondrial genome of sterlet (acipenser ruthenus).the complete mitochondrial genome of sterlet (acipenser ruthenus) was determined in this study. the mitogenome is 16,790 bp in length and contains 13 protein-coding genes, 22 transfer rna genes, 2 ribosomal rna genes and 2 non-coding regions (the control region and the putative origin of the light strand replication) with a typical vertebrate mitochondrial gene arrangement. the overall base composition of the heavy strand is 30.26% for a, 29.00% for c, 16.23% for g and 24.51% for t, with a sligh ...201524021000
lateralisation of rotational swimming but not fast escape response in the juvenile sterlet sturgeon, acipenser ruthenus (chondrostei: acipenseridae).for the first time, behavioural lateralisation was shown in a chondrostean fish (sterlet sturgeon acipenser ruthenus). a significant directional bias was found in young a. ruthenus swimming along a circular swimway. this laterality manifested itself as an individual preference for a certain movement direction (either clockwise or counterclockwise) which was consistent at the retest 10 days later. on the other hand, no significant rotational bias was observed at the population level. the same ste ...201423758344
in vitro effects of bisphenol a on the quality parameters, oxidative stress, dna integrity and adenosine triphosphate content in sterlet (acipenser ruthenus) spermatozoa.among endocrine disruptors, the xenoestrogen bisphenol a (bpa) deserves particular attention due to widespread human exposure. besides hormonal effects, bpa has been suspected to be responsible for adverse effect on reproductive ability of various species. in the present study the effect of bpa on the quality parameters, oxidative stress, the dna integrity and intracellular atp content of sterlet (acipenser ruthenus) spermatozoa were investigated in vitro. fish spermatozoa were exposed to concen ...201323680852
the in vitro effect of duroquinone on functional competence, genomic integrity, and oxidative stress indices of sterlet (acipenser ruthenus) spermatozoa.the sturgeon is a highly endangered fish species mostly due to over-fishing, habitat destruction, and water pollution. duroquinone (derivative of 1,4-benzoquinone) is a xenobiotic compound widespread in the environment. the effect of duroquinone on motility, dna integrity, and oxidative stress indices in sterlet, acispenser ruthenus, spermatozoa was investigated. sterlet sperm was exposed for 2h to duroquinone at concentrations of 25, 50, 100, and 150 μm. spermatozoa motility, velocity, and atp ...201323587503
motility of sturgeon spermatozoa can sustain successive activations we report for the first time the possibility of sequential sperm motility activation in sturgeon (sterlet, acipenser ruthenus), a fish with external fertilization, through changes either in osmolality (global solute concentration) or in the ca(2+) concentration of the medium surrounding the spermatozoa. sperm motility was initiated in any of three solutions containing buffer and sucrose at 80, or 40 or 10mm (called s80, s40, s10, respectively); s80 is hypertonic relative to sterlet seminal ...201323528713
short-term storage of sterlet acipenser ruthenus testicular cells at -80 °c.the conservation of sturgeons is of critical importance, and optimization of long-term storage is crucial to cell survival. this study aimed to examine the viability rates of several variations of sturgeon testicular cells storage at -80 °c for purpose of a short-term storage in a deep freezer or shipment on dried ice. testes extracted from three immature fish were cut into small pieces, immersed in a cryomedium composed of phosphate buffered saline with 0.5% bovine serum albumin, 50 mm glucose, ...201626964775
first report on facultative parthenogenetic activation of eggs in sterlet sturgeon, acipenser ruthenus.this study reported facultative parthenogenetic cleavage development of sterlet sturgeon acipenser ruthenus eggs and quantified the percentage of parthenogenetically developed eggs in relation to the fertilization ability of different females. when eggs were activated in freshwater, 5.1-13.7% of eggs developed parthenogenetically, while among those activated eggs 3.6-9.4% developed to 2 cells, 0.4-4.5% developed to 4 cells, and 0-0.8% developed to 8 cells. the mean percentage of fertilized and p ...201626952761
changes of vitellogenin and lipase in captive sterlet sturgeon acipenser ruthenus females during previtellogenesis to early atresia.plasma chemistry, lipid metabolism and vitellogenin gene expression of captive sterlet sturgeon acipenser ruthenus were studied in different maturity stages. a total of 32 fish were sampled, and maturity stages were identified on the basis of histological criteria and direct observation. females were classified to four groups: previtellogenic, vitellogenic, post-vitellogenic, and atresia. blood, gonad and liver tissue samples were taken through non-lethal biopsy. our results showed that plasma l ...201626732070
sterilization of sterlet acipenser ruthenus by using knockdown agent, antisense morpholino oligonucleotide, against dead end gene.sturgeons (chondrostean, acipenseridae) are ancient fish species, widely known for their caviar. nowadays, most of them are critically endangered. the sterlet (acipenser ruthenus) is a common eurasian sturgeon species with a small body size and the fastest reproductive cycle among sturgeons. such species can be used as a host for surrogate production; application is of value for recovery of critically endangered and huge sturgeon species with an extremely long reproductive cycle. one prerequisit ...201526248520
novel technique for visualizing primordial germ cells in sturgeons (acipenser ruthenus, a. gueldenstaedtii, a. baerii, and huso huso).primordial germ cells (pgcs) are the origin of all germ cells in developing embryos. in the sturgeon embryo, pgcs develop from the vegetal hemisphere, which mainly acts as an extraembryonic source of nutrition. current methods for studying sturgeon pgcs require either killing the fish or using costly and time-consuming histological procedures. here, we demonstrate that visualization of sterlet (acipenser ruthenus>) pgcs in vivo is feasible by simply labeling the vegetal hemisphere with fluoresce ...201526134864
effects of pre-incubation of eggs in fresh water and varying sperm concentration on fertilization rate in sterlet sturgeon, acipenser ruthenus.standardization of fertilization protocols for sterlet acipenser ruthenus is crucial for improving reproductive techniques and for conservation purposes. our objectives were to determine the number of sperm (tested 430,000:1, 43,000:1, 4300:1, 430:1 sperm to egg) required to fertilize eggs and explore how pre-incubation of eggs in freshwater for 0min, 0.5min, 1min, and 10min interacts with different sperm ratios. fertilization success ranged from 29.7% at 430:1 to 84.2% at 430,000:1. pre-incubat ...201526119142
influence of environmentally relevant concentrations of vinclozolin on quality, dna integrity, and antioxidant responses of sterlet acipenser ruthenus spermatozoa.the effects of vinclozolin (vin), an anti-androgenic fungicide, on quality, oxidative stress, dna integrity, and atp level of sterlet (acipenser ruthenus) spermatozoa were investigated in vitro. fish spermatozoa were incubated with different concentrations of vinclozolin (0.5, 2, 10, 15, 20 and 50 μg/l) for 2 h. a dose-dependent reduction in spermatozoa motility and velocity was observed at concentrations of 2-50 μg/l. a dramatic increase in dna fragmentation was recorded at concentrations 10 μg ...201323376258
site heteroplasmy in the mitochondrial cytochrome b gene of the sterlet sturgeon acipenser ruthenus.sturgeons are fish species with a complex biology. they are also characterized by complex aspects including polyploidization and easiness of hybridization. as with most of the ponto-caspian sturgeons, the populations of acipenser ruthenus from the danube have declined drastically during the last decades. this is the first report on mitochondrial point heteroplasmy in the cytochrome b gene of this species. the 1141 bp sequence of the cytb gene in wild sterlet sturgeon individuals from the lower d ...201223271951
[electron microscopy study of the frontal neurohypophysis of the sterlet acipenser ruthenus]. 200612815976
developmental structure of the vertebral column, fins, scutes and scales in bester sturgeon, a hybrid of beluga huso huso and sterlet acipenser the larval bester, a hybrid sturgeon of beluga huso huso and sterlet acipenser ruthenus, development of cartilage around the notochord began 7 days post hatch (dph) (14.0 mm, total length, l(t)). the vertebral cartilage develops in the following sequence: basidorsals and basiventrals, neural canals, neural spines and ribs. the development of ribs remained incomplete in the largest specimen (181 dph, 179 mm l(t) ) that was examined. endoskeletal development of the fins began 4 dph for the dors ...201223130694
different swimming behaviors of sterlet (acipenser ruthenus) spermatozoa close to solid and free surfaces.spermatozoa tend to swim near surfaces. such attraction toward surface vicinity was approximated by the force-dipole theoretical approach and hydrodynamic modeling, but the physical parameters of surfaces have not usually been included in these models and their effect on sperm mobility remains unknown. in spermatozoa, changes in wave parameters, together with rotation around their longitudinal axis and circling appear when movement takes place close to surfaces. here we show, by analysis of micr ...201323102849
distribution of gfap immunoreactive structures in the rhombencephalon of the sterlet (acipenser ruthenus) and its evolutionary implication.previous studies have revealed that although the brains of cypriniform teleosts (iberian barb, barbus comiza; carp, cyprinus carpio; goldfish, carassius auratus) are rich in glial fibrillary acidic protein (gfap), they have, however, areas devoid of gfap immunoreactivity. the largest ones of these are in the rhombencephalon, e.g., the zones of the sensory and motor neurons in the vagal lobe. our studies in amniotes suggested that the gfap immunonegative areas could be characteristic of the more ...200212210122
ploidy levels and the number of nuclei in cardiomyocytes of the lamprey and is well known that polyploidization of cardiomyocytes (cmc) is an essential component of heart growth in the warm-blooded vertebrates. using the feulgen cytophotometry of alkali-dissociated cells, we determined the ploidy in cmc of the lower vertebrates: lamprey lampetra fluviatilis (cyclostomata), skate bathyraja maculata (chondrostei), sterlet acipenser ruthenus, and russian sturgeon acipenser güldenstädti (ganoids), as well as paradise fish macropodus opercularis, amur sleeper perccottus g ...200212149784
effects of dietary garlic extracts on whole body amino acid and fatty acid composition, muscle free amino acid profiles and blood plasma changes in juvenile sterlet sturgeon, acipenser ruthenus.a series of studies were carried out to investigate the supplemental effects of dietary garlic extracts (ge) on whole body amino acids, whole body and muscle free amino acids, fatty acid composition and blood plasma changes in 6 month old juvenile sterlet sturgeon (acipenser ruthenus). in the first experiment, fish with an average body weight of 59.6 g were randomly allotted to each of 10 tanks (two groups of five replicates, 20 fish/tank) and fed diets with (0.5%) or without (control) ge respec ...201225049498
effects of dietary garlic extract on growth, feed utilization and whole body composition of juvenile sterlet sturgeon (acipenser ruthenus).this study was carried out to investigate the supplemental effects of dietary garlic extract (ge) on growth performance of juvenile sterlet sturgeon (acipenser ruthenus). the first experiment was designed to determine the optimum levels of garlic extract as growth promoter during 10 weeks. three groups (two replicates/group) of 240 fish with mean body weight of 85 g were fed with diets containing 0 (control), 0.5 and 1.0% of ge. the highest weight gain (%) and feed efficiency (%) were found in f ...201225049599
[the influence of testosterone on activity of glycosidases and proteinases in the intestine of the sterlet (acipenser ruthenus)].observation of the influence oftestosterone (0.7 mg/kg) on the activity ofglycosidases and proteinases, which function in the chime and the mucous coat of the sterlet intestine (acipenser ruthenus), revealed a decrease in enzyme activity of both chains as against that one typical for intact individuals. the activity of the investigated enzymes changes in both the experimental and control groups offish. nevertheless, they have unlike dynamics of this activity. in a number of cases, we indicated a ...201622117424
evaluation of spermiation indices with multiple sperm collections in endangered sterlet (acipenser ruthenus).this study investigated the effects of multiple collections of sperm on endangered sterlet (acipenser ruthenus) sperm functional parameters [spermatozoa motility and curvilinear velocity (vcl)] as well as on protein concentration and osmolality of seminal plasma. the average sperm volume and mean spermatozoa concentration per male were significantly altered with multiple collections. on the other hand, no significant effect of multiple collections on protein concentration of seminal plasma was o ...201221978021
roles of osmolality, calcium - potassium antagonist and calcium in activation and flagellar beating pattern of sturgeon sperm.the present study shows the roles of osmolality, calcium (ca(2+))-potassium (k(+)) antagonist and ca(2+) in sperm activation and flagellar beating of a sturgeon species, sterlet (acipenser ruthenus). sperm motility was activated at hypoosmolality relative to seminal plasma and suppressed at 175 mosmol kg(-1). sperm activation was totally suppressed by 0.35mm k(+), but ca(2+) could fully reverse k(+) inhibitory effect at ca(2+): k(+) ratio of 0.25. neither egta (a chelator of ca(2+) ions) nor nif ...201121651987
influence of environmental related concentrations of heavy metals on motility parameters and antioxidant responses in sturgeon sperm.the effects of heavy metals (cd, cr and cd+cr) on the motility parameters and oxidative stress of sterlet (acipenser ruthenus) sperm were investigated in vitro. sturgeon sperm were exposed for 2h to heavy metals at environmental related concentrations (0.1mgl(-1) cr, 0.001mgl(-1) cd, 0.1mgl(-1) cr+0.001mgl(-1) cd) and higher concentrations (5.0mgl(-1) cr, 0.05mgl(-1) cd, 5.0mgl(-1) cr+0.05mgl(-1) cd). results revealed that environmental concentrations of heavy metals had no significant influence ...201020836996
liver, gills, and skin histopathology and heavy metal content of the danube sterlet (acipenser ruthenus linnaeus, 1758).the sterlet (acipenser ruthenus l.) is a bottom-feeding fish species with a direct exposure to contaminants from water and sediments. although heavy metal pollution is believed to be one of the main threats to the sterlet population in the danube river basin, there is a lack of knowledge of the exact impact of heavy metals on their survival. in the present study, effects of heavy metal pollution on sterlet in the danube basin were assessed as well as the utility of different sterlet organs and t ...201020821473
image cytometric measurements of diploid, triploid and tetraploid fish erythrocytes in blood smears reflect the true dimensions of live cells.comparative image cytometry of erythrocytes of diploid and triploid tench tinca tinca l. and evolutionary tetraploid sterlet acipenser ruthenus l. was performed on whole live unstained cells, live cells with stained nuclei and on stained fixed whole cells and their nuclei to test if erythrocyte measurements made from blood smears reflect the true dimensions of live cells. nuclear area and perimeter were the best ploidy level predictors distinguishing accurately among live and fixed diploid, trip ...201120812918
[buffer, respiratory properties, and ion surrounding of hemoglobin in the sterlet acipenser ruthenus]. 201620583587
size determination of acipenser ruthenus spermatozoa in different types of electron this study three types of scanning electron microscopes were used for the size determination of spermatozoa of sterlet acipenser ruthenus - high vacuum scanning electron microscope (sem, jeol 6300), environmental scanning electron microscope (esem, quanta 200 feg), field emission scanning electron microscope (fesem, jeol 7401f) with cryoattachment alto 2500 (gatan) and transmission electron microscope (tem, jeol 1010). the use of particular microscopes was tied with different specimen prepara ...201020226681
a visual pigment of the sturgeon retina.the visual pigments of hybrid sturgeon (a cross between acipenser ruthenus (male) and huso huso (female) have been studied both by the methods of incomplete partial bleaching and hplc analysis. on the basis of the results obtained the relationship between the structure of opsins and the spectral characteristics of visual pigments is discussed.19892920798
vascularization of the telencephalic choroid plexus of a ganoid fish [acipenser ruthenus (l.)].the vascularization of the telencephalic choroid plexus of the sterlet acipenser ruthenus, a ganoid fish, was examined by vascular corrosion casting and by light and transmission electron microscopy. the arterial supply is from the dorsal mesencephalic artery via: 1) the ventral choroidal arteries (left and right); 2) the dorsal choroidal arteries (left and right); 3) the caudal choroidal arteries (left and right); 4) the ventral arteries of the dorsal sac; and, from the olfactory arteries, via ...19883389312
first evidence of autotriploidization in sterlet (acipenser ruthenus).polyploidization has played an important role in vertebrate evolution. acipenseridae bring clear examples of polyploidy ancestry and, also, polyploidization seems to be an ongoing process in these fishes. in the present study, the genetic origin of six triploid specimens morphologically determined as acipenser ruthenus from commercial aquaculture was analyzed using a combination of mitochondrial and nuclear markers. a further five successive statistical analyses including median joining of mitoc ...201323456847
acrosome staining and motility characteristics of sterlet spermatozoa after cryopreservation with use of methanol and this study we describe acrosome staining and motility characteristics of fresh and cryopreserved sterlet (acipenser ruthenus l.) spermatozoa using soybean trypsin inhibitor-alexa conjugate fluorescent staining and computer-aided sperm analysis (casa), respectively. methanol or dimethylsulfoxide (dmso) were used as cryoprotectants. after cryopreservation a decline in sperm motility characteristics occurred, but no differential effect between cryoprotectant was observed. cryopreservation caused ...200818466892
fine structure and morphology of sterlet (acipenser ruthenus l. 1758) spermatozoa and acrosin localization.ultrastructure of sterlet acipenser ruthenus l. 1758 sperm was examined by scanning and transmission electron microscopy, which allowed us to use various methods for visualizations of different parts of sterlet spermatozoa. sperm cells possess a head with a distinct acrosome, a midpiece and a single flagellum surrounded by the flagellar plasma membrane. the average length of the head including the acrosome and the midpiece was estimated as 5.14+/-0.42 microm. nine to 10 posterolateral projection ...200918359585
expression of igf-i and igf-i receptor in male and female sterlet, acipenser ruthenus--evidence for an important role in gonad maturation.recent in vitro studies suggest that insulin-like growth factor i (igf-i) is involved in cell differentiation and steroidogenesis in the gonad and could therefore function as an important trigger in vivo. in this study, sensitive real-time rt-pcr assays were used to determine igf-i and the igf-i receptor (igf-ir) mrna expression in maturing male and female sterlet (acipenser ruthenus) over a period of two years: in the first year, females entering vitellogenesis (maturing female group, mfg) reve ...200717289414
analysis of microvascular trees by means of scanning electron microscopy of vascular casts and 3d-morphometry.arterial and capillary trees form by consecutive branching (mostly bifurcations) from a stem vessel, venous trees form by repeated merging of blood vessels. diameters of stem (parent, mother) vessels and daughter vessels (branches), interbranching distances and branching angles between stem and daughter vessels lastly define the overall three-dimensional structure of the vascular network as well as the basic transport capacity of the system. here we use scanning electron microscopy and 3d-morpho ...200516101025
design of cerebellar and nontegmental rhombencephalic microvascular bed in the sterlet, acipenser ruthenus: a scanning electron microscope and 3d morphometry study of vascular corrosion casts.the design of the microvasculature of cerebellum and nontegmental rhombencephalic areas was studied in eight adult acipenser ruthenus l. by scanning electron microscopy of vascular corrosion casts and three-dimensional morphometry. gross vascularization was described and diameters and total branching angles of parent and daughter vessels of randomly selected arterial and capillary bifurcations (respectively, venous mergings) were measured. with diameters ranging from 15.9 +/- 1.9 microm (cerebel ...200616984664
the role of the igf-i system for vitellogenesis in maturing female sterlet, acipenser ruthenus linnaeus, 1758.transition from previtellogeneic to vitellogenic oocyte growth is a critical phase for folliculogenesis in sturgeon and may often be postponed for several years. recent findings on the involvement of insulin-like growth factor i (igf-i) in cell differentiation processes of oocyte follicle and ovarian steroidogenesis of teleosts in vitro led to the hypothesis that paracrine igf-i could function as a potential trigger in vivo. for the first time, igf-i and its corresponding receptor (igf-ir) were ...200716945369
assessing pollution in the danube river near novi sad (serbia) using several biomarkers in sterlet (acipenser ruthenus l.).the response of wild fish to pollutants was studied in sterlet (acipenser ruthenus l.) collected in 2001 and 2002 at two sampling sites in the danube river near novi sad (serbia): in the vicinity of the oil refinery and at the danube-begec, remote from the oil refinery and considered a reference site. the following biomarkers were measured in sterlet collected from these two sites: the activities of superoxide dismutase (sod), catalase, glutathione peroxidase (gsh-px), and glutathione s-transfer ...200616194569
comparative scanning electron microscopy of the ventricular surface in four actinopterygian fishes: acipenser ruthenus, salmo gairdneri, tinca tinca and blennius sanquinolentus (pisces).the ventricular surface structure of the brains of actinopterygian fishes representing four distinct evolutionary levels was investigated by scanning electron microscopy (sem). in the chondrostean acipenser ruthenus ventricular spaces are wide and the ependymal surface is for the greater part densely covered with cilia; apart from macrophages supraependymal cells (se) are very scarce. in the teleosts salmo gairdneri, tinca tinca and blennius sanquinolentus the ventricles are slit-like, the dense ...19853989278
[age and changes in the structure of the neurohypophysis of the sterlet, acipenser ruthenus l].the results are given of histophysiological study of neurohypophysis in sexually mature sterlets (acipenser ruthenus l.) of different age. an attention is paid to the age morphological changes of neurohypophysis and, in particular, to the number, size and topography of large and giant widenings of neurosecretory fibers, so-called gerring bodies. the relation between the frequency of gerring bodies and the age of fishes was followed. a suggestion is put forward to the effect that the appearance o ...1977882241
[receptor cells of different types and quantitative relations between them in the organ of smell of larval and adult specimens of acipenserid fishes].three types of olfactory cells: rod-like and cone-like (flagellar olfactory cells) and filamentous (microvillar olfactory cells), which have been described previously in adult acipenseridae were found in the olfactory organ of the ten-days larval sturgeons (acipenser güldenstädti), sevrugas (acipenser stellatus) and sterlets (acipenser ruthenus). the flagellar olfactory receptors appeared to predominate in both ten-days larvae and adults of the anadromous sturgeons and sevrugas, while the microv ...19761030860
the genus acipenser as a model for vertebrate urogenital development: the müllerian duct.the development of the müllerian duct was studied in a total of 85 specimens of acipenser ruthenus and acipenser baeri in the period from 7 days after hatching through 5 years of age. normal histology on serial sections, transmission and scanning electron microscopy and bromodeoxyuridine immunohistochemistry were applied. in acipenser, the primary set of opisthonephric nephrons possess short nephrostomial tubules with well-developed nephrostomes. proliferating cells from the lateral side of the ...200312649724
the genus acipenser as a model for vertebrate urogenital development: ultrastructure of nephrostomial tubule formation and of initial gonadogenesis.the ultrastructure of the nephrostomial tubule and the gonadal crest of acipenser ruthenus were studied by transmission and scanning electron microscopy. opisthonephric nephrostomial tubules begin to appear at the end of the first week after hatching and are regularly segmentally arranged and completely developed in the period between 10 and 35 days after hatching. fully differentiated nephrostomial tubules connect the vestibular area of the malpighian corpuscle with the coelomic cavity as short ...200212392324
[electron microscopic study of the olfactory organ of the sterlet (acipenser ruthenus)].three variations of olfactory cells were found in the olfactory organ of the sterlet acipenser ruthenus. they were different in the shape of their peripheral processes: rod-shaped ones supplied with flagella and solitary microvilla; cone-shaped ones with solitary flagella and a great number of microvilla; filiform ones without flagella but with numerous microvilla and groups of centrioles in the cytoplasm of the peripheral process. the character of the structural and functional organization of t ...19751200864
ultrastructure of neurosecretory cells at different stages of differentiation in the preoptic nucleus of immature sterlet.ultrastructure of neurosecretory cells of the preoptic nucleus in immature sterlet (acipenser ruthenus l.) was studies for the first time. the dorsal zone of the preoptic nucleus houses light, dark, and pycnomorphic neurosecretory cells, which contain varying numbers of elementary secretory granules measuring 1995 plus or minus 32 a in diameter. light cells containing numerous secretory granules with a diameter of 1707 plus or minus 27 a are predominant in the middle zone. pycnomorphic cells are ...19751124423
[head blood vessels of the sterlet (acipenser ruthenus l.) (acipenseridae, chondrostei)]. 19734730634
a method for hypophysectomy in the young sturgeon acipenser ruthenus l. 20035154595
[histologic studies on the gonads, thyroid gland, and pituitary in acipenser ruthenus in natural conditions in ponds and rivers]. 195313095293
immunoglobulin heavy chain constant region of five acipenseridae: cdna sequence and evolutionary relationship.the immunoglobulin m (igm) heavy chain constant region genes of russian sturgeon (acipenser gueldenstaedtii), sterlte sturgeon (acipenser ruthenus), amur sturgeon (acipenser schrenckii), chinese sturgeon (acipenser sinensis) and great sturgeon (huso huso) were cloned and analyzed with molecular biology and bioinformatics methods. we cloned igh nucleic acid sequences by rt-pcr using the specific primer, then determined the characteristics and functions of the amino acid sequences. the gene contai ...200717234432
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