843 resultados para crucian carp (Carassius auratus)


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The relationship between photoperiod, plasma concentration of ionic calcium and the histology of the prolactin-secreting cells of the rostral pars distalis of the pituitary gland, the Corpuscles of Stannius and the Ultimobranchial gland were investigated. Neither the plasma concentration of ionic calcium nor histologically apparent prolactin cell activity could be correlated with photoperiod. Some evidence of a photoperiodic effect on both the Corpuscles of Stannius and the Ultimobranchial gland was obtained. The expected reciprocal relationship between the activity of these glands was not obvious at the histological level . Quantitative and qualitative analysis at the light microscope level revealed, however, that the hormone prolactin-secreting eta cells of the rostral pars distalis and the hypocalcin-secreting cells of the Corpuscles of Stannius may be arranged in a lamellar pattern comprized of synchronous bands of cells in like-phase of a secretory cycle consisting of four stages - synthesis, storage, release and reorganization. Such synchronized cell cycles in these glands have not heretofore been described in literature. It is suggested that the maintenance of at least 255? of the cells in any one phase of the cycle ensures a supply of the required hormone at all times.

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The effects of a diurnal sine-wave temperature cycle (250 +- 5° C) on the wa terI-e etc r o1 yt est a t us 0 f gol df1' Sh , Carassius auratus, was assessed through determination of Na+, K+, Mg2+, Ca2+, Cl- and water content in plasma, Red blood cells and muscle tissue. Animals were also acclimated to o 0 0 static temperatures (20 C, 25 c, 30 C) corresponding to the high, low and mid-ooint temperatures of the cycle. All groups were sampled at 03:00, 09:00, 15:00 and 21:00 hr. Hemoglobin content and packed cell volume, as well as electrolyte and 'water levels were determined for each animal and red cell ion concentrations and ion : hemoglobin ratios estimated. Cycled animals were distinct from those at constant temperatures in several respects. Hematological parameters were elevated above those of animals at constant temperature and were, on a diurnal basis, more stable. Red blood cell electrolyte levels varied in an adaptively appropriate fashion to cycle temperatures. This was not the case in the constant temperature groups_ Under the cycling regime, plasma ion levels were more diurnally stable than those of constant temperature fish. Although muscle parameters in cycled fish exhibited more fluctuation than was observed in plasma, these also tended to be relatively more stable than was the caseErythrocytic data are discussed in terms of their effects on hemoglobin-oxygen affinity while plasma and muscle observations were considered from the standpoint of overall water-electrolyte balance. In general, cycled fish appeared to be capable of stabilizing overall body fluid composition, while simultaneously effecting adaptively-appropriate modifications in the erythrocytic ionic microenvironment of hemoglobin. The sometimes marked diurnal variability of water-electrolyte status in animals held at constant temperature as opposed to the conservation of cycled fish suggests that this species is, in some fashion, programmed for regulation in a thermally-fluctuating environment. If this interpretation is valid and a phenomenon of general occurrence, some earlier studies involving constant acclimation of eurythermal species normally occupying habitats which vary in temperature on a daily basis may require reconsideration. at constant temperature.

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Although it is widely assumed that temperature affects pollutant toxicity, few studies have actually investigated this relationship. Moreover, such research as has been done has involved constant temperatures; circumstances which are rarely, if ever, actually experienced by north temperate, littoral zone cyprinid species. To investigate the effects of temperature regime on nickel toxicity in goldfish (Carassius auratus L.), 96- and 240-h LCSO values for the heavy metal pollutant, nickel (NiCI2.6H20), were initially determined at 2DoC (22.8 mg/L and 14.7 mg/L in artificially softened water). Constant temperature bioassays at 10°C, 20°C and 30°C were conducted at each of 0, 240-h and 96-h LCSO nickel concentrations for 240 hours. In order to determine the effects of temperature variation during nickel exposure it was imperative that the effects of a single temperature change be investigated before addressing more complex regimes. Single temperature changes of + 10°C or -10°C were imposed at rates of 2°C/h following exposures of between 24 hand 216 h. The effects of a single temperature change on mortality, and duration of toxicant exposure at high and low temperatures were evaluated. The effects of fluctuating temperatures during exposure were investigated through two regimes. The first set of bioassays imposed a sinewave diurnal cycle temperature (20.±.1DOC) throughout the 10 day exposure to 240-h LeSO Ni. The second set of investigations approximated cyprinid movement through the littoral zone by imposing directionally random temperature changes (±2°C at 2-h intervals), between extremes of 10° and 30°C, at 240-h LC50 Ni. Body size (i.e., total length, fork length, and weight) and exposure time were recorded for all fish mortalities. Cumulative mortality curves under constant temperature regimes indicated significantly higher mortality as temperature and nickel concentration were increased. At 1DOC no significant differences in mortality curves were evident in relation to low and high nickel test concentrations (Le., 16 mg/L and 20 mg/L). However at 20°C and 30°C significantly higher mortality was experienced in animals exposed to 20 mg/L Ni. Mortality at constant 10°C was significantly lower than at 30°C with 16 mg/L and was significantly loWer than each of 2DoC and 39°C tanks at 20 mg/L Ni exposure. A single temperature shift from 20°C to 1DoC resulted in a significant decrease in mortality rate and conversely, a single temperature shift from 20°C to 30°C resulted in a significant increase in mortality rate. Rates of mortality recorded during these single temperature shift assays were significantly different from mortality rates obtained under constant temperature assay conditions. Increased Ni exposure duration at higher temperatures resulted in highest mortality. Diurnally cycling temperature bioassays produced cumulative mortality curves approximating constant 20°C curves, with increased mortality evident after peaks in the temperature cycle. Randomly fluctuating temperature regime mortality curves also resembled constant 20°C tanks with mortalities after high temperature exposures (25°C - 30°C). Some test animals survived in all assays with the exception of the 30°C assays, with highest survival associated with low temperature and low Ni concentration. Post-exposure mortality occurred most frequently in individuals which had experienced high Ni concentrations and high temperatures during assays. Additional temperature stress imposed 2 - 12 weeks post exposure resulted in a single death out of 116 individuals suggesting that survivors are capable of surviving subsequent temperature stresses. These investigations suggest that temperature significantly and markedly affects acute nickel toxicity under both constant and fluctuating temperature regimes and plays a role in post exposure mortality and subsequent stress response.

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Aiming to evaluate the enzymatic complex supplementation in diets for goldfish fingerlings (Carassius auratus), 240 fish weighing initially 1,36 ± 0,02g, randomly distributed in 20 tanks with 150L, in four treatments and five replications, with twelve fish in each experimental unit were used. The fish were fed at 8:00 and 11:00 a.m. and 2:00 and 5:00 p.m. with diets containing different inclusion levels (0; 0,033; 0,066 e 0,099%) of enzymatic complex (amilase, protease, celulase, lipase, â-glucanase and phytase), and formulated with 32,36% of digestible protein and 3.023kcal of digestible energy kg-1. There were no differences observed (P>0,05) in the mean final weight, weight gain, total length, standard length, survival and carcass composition. However, the fish apparent feed conversion was impaired by the supplementation of enzymatic complex with 0,099% in diet. The use of enzymatic complex does not provides benefits in the productive performance for goldfish fingerlings.

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Vitamin A is important to the proper development and functioning of the body, appearing in several metabolic functions. This experiment was conducted with aim evaluate to the vitamin A supplementation in diets for Goldfish Carassius auratus. The experimental was completely randomized with six treatments (0, 2.000, 4.000, 8.000, 16.000 and 32.000 IU of vitamin A kg(-1) diet) with four repetitions into 24 experimental cages, with capacity for 150 liters useful volume, made of mesh shading, installed inside a masonry circular tank with a capacity of 25 m(3) of water. 192 fish with an average initial weight of 6.66 +/- 0.57 g and initial length of 7.30 +/- 0.33 cm, feed at 8h, 11h, 14h and 17h at satiety were used. Evaluated the effects on productive performance and intensity of yellow-red coloring of the skin of the fish were. The Linear Response Plateau analysis of weight gain and length total, feed conversion and daily growth rate versus vitamin A requirement estimate showed 2,624, 2,385 and 2,358, 4,381 and 2,866 IU of vitamin A per kg diet, respectively. The data indicated that this vitamin has little or no influence on the intensity of the skin color of the Goldfish.

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Ziel der Arbeit war es zu klären, ob und auf welche WeiseGoldfische die Farben des Spektrums in Kategorien einteilen.Die Fische wurden dazu auf zwei bzw. sechs Wellenlängendressiert. Bei zwei Dressurwellenlängen durchliefen dieTiere verschiedene Tests. Sowohl der Transfertest, als auchder Generalisierungstest zeigten Ergebnisse, die nichtalleine mit der Wellenlängenunterscheidungsfähigkeit derFische erklärt werden können, sondern auf eineKategorisierung der Farben hindeuten. Dabei zeigt es sich,dass es zwischen 540 nm und 608 nm keinen direkten Überganggibt, während Bereiche zwischen anderen Wellenlängen, z.B.zwischen 438 und 501 nm, größere Ähnlichkeiten aufwiesen.Die Generalisierungsergebnisse der Versuche mit sechsDressurwellenlängen lassen eine genauere Einteilung desWellenlängenspektrums zu. Hier traten deutliche Unterschiedein den Wahlhäufigkeiten auf. Wenn man die Maxima derWahlhäufigkeiten als Prototypen einer Kategorie definiertund die Bereiche mit geringen Wahlhäufigkeiten alsÜbergangsbereich zwischen zwei Kategorien, so ergeben sichfünf bzw. sechs Kategorien, wenn man den breiten Bereich(zwischen 515 und 580 nm) mit niedrigen Wahlhäufigkeiten alseigene Kategorie wertet. Bezieht man die Ergebnisse derDressur auf zwei Wellenlängen mit ein, so ergibt sich eineEinteilung des Wellenlängenspektrums des Goldfisches von 388nm bis 685 nm in sieben Kategorien.

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Das Ziel der vorliegenden Arbeit bestand darin, mit Hilfe von Scheinkonturen und Größentäuschungen durch psychophysische Methoden die Formen- und Größenwahrnehmung beim Goldfisch zu untersuchen. Zur Klärung dieser Frage wurden Dressurexperimente durchgeführt und unter Verwendung zweier verschiedener Untersuchungsmethoden das Verhalten der Versuchstiere bestimmt. Die Ergebnisse zeigen, dass der Goldfisch verschiedene Scheinkonturen wahrnehmen kann. Voraussetzung hierfür ist, dass sich diese Scheinkonturen durch klare Kanten vom Hintergrund abgrenzen. Die Untersuchung der verschiedenen Größentäuschungen zeigte kein einheitliches Ergebnis. Sowohl bei der MÜLLER-LYER- als auch bei der PONZO-Täuschung zeigten sich die Versuchstiere in ihrem Verhalten unabhängig von den Bestandteilen der Täuschungsfiguren, die die Dressurreize umgaben. Sie ließen sich also durch die Figuren nicht „täuschen“, sondern richteten sich nur nach ihren Dressurformen. Nur bei der EBBINGHAUS-Täuschung ließen sich die Versuchstiere von den umgebenden Elementen beeinflussen und bevorzugten die Täuschungsfigur. Allgemein zeigte sich, dass die Fische ihre jeweiligen Dressurstimuli sehr genau erlernt hatten und eine erlernte Unterscheidungsfähigkeit nicht auf anderen Formen oder Größen übertrugen. Zusätzlich wurde bei zwei unterschiedlichen Formen der minimale Größenunterschied ermittelt, der notwendig ist, um die beiden Formen als unterschiedlich groß wahrzunehmen. Die Messungen ergaben sehr deutliche Unterschiede in den absoluten Größenunterschieden bei den zwei getesteten Arten von Formen. Vergleicht man jedoch das Flächenverhältnis der beiden Größen der jeweiligen Figur, bei der eine Größenunterscheidung gerade noch möglich war, so stellt man fest, dass dieses Verhältnis bei beiden Formen identisch ist. Lediglich der Sehwinkel kann bei kompakteren Figuren kleiner sein, um zwei verschiedene Größen noch voneinander unterscheiden zu können.

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In der vorliegenden Arbeit wurde das Objektbewegungssehen des Goldfischs betrachtet. Zuerst musste eine geeignete Methode gefunden werden, diese Form der Bewegungswahrnehmung untersuchen zu können, da bisherige Experimente zum Bewegungssehen beim Goldfisch ausschließlich mit Hilfe der optomotorischen Folgereaktion gemacht wurden. Anschließend sollte die Frage geklärt werden, ob das Objektbewegungssehen genau wie das Bewegungssehen einer Großfeldbewegung farbenblind ist und welcher Zapfentyp daran beteiligt ist. Die Verwendung eines Zufallpunktmusters zur Dressur auf ein bewegtes Objekt hat sich als äußert erfolgreich herausgestellt. Diese Methode hat den Vorteil, dass sich die Versuchstiere ausschließlich aufgrund der Bewegungsinformation orientieren können. In den Rot-Grün- und Blau-Grün-Transferversuchen zeigte sich, dass das Objektbewegungssehen beim Goldfisch farbenblind ist, aber erstaunlicherweise nicht vom L-Zapfen vermittelt wird, sondern wahrscheinlich vom M-Zapfen. Welchen Vorteil es haben könnte, dass für die verschiedenen Formen der Bewegungswahrnehmung verschiedene Eingänge benutzt werden, kann mit diesen Versuchen nicht geklärt werden. Farbenblindheit des Bewegungssehens scheint eine Eigenschaft visueller Systeme allgemein zu sein. Beim Menschen ist diese Frage im Moment noch nicht geklärt und wird weiterhin diskutiert, da es sowohl Experimente gibt, die zeigen, dass es farbenblind ist, als auch andere, die Hinweise darauf geben, dass es nicht farbenblind ist. Der Vorteil der Farbenblindheit eines bewegungsdetektierenden visuellen Systems zeigt sich auch in der Technik beim Maschinen Sehen. Hier wird ebenfalls auf Farbinformation verzichtet, was zum einen eine Datenreduktion mit sich bringt und zum anderen dazu führt, dass korrespondierende Bildpunkte leichter gefunden werden können. Diese werden benötigt, um Bewegungsvektoren zu bestimmen und letztlich Bewegung zu detektieren.

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In the goldfish (Carassius auratus) the two endogenous forms of gonadotropin-releasing hormone (GnRH), namely chicken GnRH II ([His5,Trp7,Tyr8]GnRH) and salmon GnRH ([Trp7,Leu8]GnRH), stimulate the release of both gonadotropins and growth hormone from the pituitary. This control is thought to occur by means of the stimulation of distinct GnRH receptors. These receptors can be distinguished on the basis of differential gonadotropin and growth hormone releasing activities of naturally occurring GnRHs and GnRHs with variant amino acids in position 8. We have cloned the cDNAs of two GnRH receptors, GfA and GfB, from goldfish brain and pituitary. Although the receptors share 71% identity, there are marked differences in their ligand selectivity. Both receptors are expressed in the pituitary but are differentially expressed in the brain, ovary, and liver. Thus we have found and cloned two full-length cDNAs that appear to correspond to different forms of GnRH receptor, with distinct pharmacological characteristics and tissue distribution, in a single species.

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[EN]The integrated culture of fish and plant in a recirculated system is called aquaponics, where a mutual benefit have been demonstrated for the cocultured species. Today this practice is still not well known for the most studied consumed freshwater species, and almost nothing has been done for aquarium species. The objective of present work was to study the opportunity of growing one of the most selled aquarium plant coontail (Ceratophyllum demersum) in a coculture with the goldfish (Carassius auratus) from which a nutritional trial was planned.

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萍乡肉红鲫(Pingxiang red-transparent crucian carp,Carassius auratusL.)是在江西省萍乡地区分布的天然三倍体鲫突变体经人工选育后获得的遗传性状基本稳定的后代,具有两性生殖和雌核生殖两种生殖方式。研究以F5代萍乡肉红鲫为材料,自孵化后每满1个月开始取性腺,观察了其卵巢1周年性成熟和精巢的发育过程,结果表明萍乡肉红鲫的性腺为1年成熟类型。卵巢发育进程可以分为6个时期,卵母细胞发育相应可分为6个时相。统计了卵巢成熟系数周年变化,体重为95 g左右的雌性萍乡

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Hexabromocyclododecanes (HBCDs) are now emerging ubiquitous contaminants due to their wide usage, persistence and toxicities. To investigate the bioaccumulative characteristics of HBCDs, sediments, Winkle (Littorina littorea), crucian carp (Carassius carassius) and loach (Misgurnus anguillicaudatus) were collected from two streams near an E-waste dismantling site in China. and HBCD exposure test was then conducted on Chinese rare minnow. The concentration of HBCDs was 14 ng g(-1) dry weight in sediments, 186. 377 and 1791 ng g(-1) lipid weight in winkle, crucian carp and loach, respectively. gamma-HBCD was found to be the dominant diastereoisomer in the sediments (63% of total HBCDs). However, alpha-HBCD was selectively accumulated in the biotic samples and contributed to 77%, 63% and 63% of total HBCDs in winkle, crucian carp and loach, respectively. Moreover, an enrichment of (-)-enantiomers of alpha- and gamma-HBCD were found in the winkle. The reverse results were observed in the crucian carp and loach. Similar observations of diastereoisomeric and enantiomeric composition were obtained in Chinese rare minnow with those found in the crucian carp and loach. These results indicate that the freshwater species from the streams are contaminated by HBCDs. alpha-HBCD can be selectively accumulated in organisms and the accumulative characteristics are enantioselective among species. (C) 2009 Elsevier Ltd. All rights reserved.

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Anterior gradient 2 (Agr2) genes encode secretory proteins, and play significant roles in anterior-posterior patterning and tumor metastasis. Agr2 transcripts were shown to display quite diverse tissue distribution in different species, and little was known about the cellular localization of Agr2 proteins. In this study, we identified an Agr2 homologue from gibe[ carp (Carassius auratus gibelio), and revealed the expression patterns and cellular localization during embryogenesis and in adult tissues. The full-length cDNA of CagAgr2 is 803 nucleotides (nt) with an open reading frame of 510 nt encoding 169 amino acids. The Agr2 C-terminus matches to the class I PDZ-interacting motif, suggesting that it might be a PDZ-binding protein. During embryogenesis, CagAgr2 was found to be transcribed in the mucus-secreting hatching gland from tailbud stage and later in the pharynx region, swim bladder and pronephric duct as revealed by RT-PCR and whole mount in situ hybridization. In the adult fish, its transcription was predominantly confined to the kidney, and lower transcription levels were also found in the intestine, ovary and gills. To further localize the Agr2 protein, the anti-CagAgr2 polyclonal antibody was produced and used for immunofluorescence observation. In agreement with mRNA expression data, the Agr2 protein was localized in the pronephric duct of 3dph larvae. In adult fish, Agr2 protein expression is confined to the renal collecting system with asymmetric distribution along the apical-basolateral axis. The data provided suggestive evidence that fish Agr2 might be involved in differentiation and secretory functions of kidney epithelium. (C) 2009 Elsevier Inc. All rights reserved.

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Apo-14 is a fish-specific apolipoprotein and its biological function remains unknown. In this study, CagApo-14 was cloned from gibel carp (Carassius auratus gibelio) and its expression pattern was investigated during embryogenesis and early larval development. The CagApo-14 transcript and its protein product were firstly localized in the yolk syncytial layer at a high level during embryogenesis, and then found to be restricted to the digestive system including liver and intestine in later embryos and early larvae. Immunofluorescence staining in larvae and adults indicated that CagApo-14 protein was predominantly synthesized in and excreted from sinusoidal endothelial cells of liver tissue. Morpholino knockdown of CagApo-14 resulted in severe disruption of digestive organs including liver, intestine, pancreas and swim bladder. Moreover, yolk lipid transportation and utilization were severely affected in the CagApo-14 morphants. Overall, this data indicates that CagApo-14 is required for digestive system organogenesis during fish embryogenesis and larval development.