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Introduction of non‐native fish species has been criticized as one of the major threats to freshwater ecosystems. During recent years, the cyprinid fish genus Carassius has been the subject of various studies in terms of introduction biology and ecology. The taxonomy and identification of described species in the genus Carassius is still ambiguous. In order to increase the knowledge of introduced species of the genus in Iran, molecular approaches were employed to identify species based on the mitochondrial gene, cytochrome b (Cyt b). In total, 417 specimens across Eurasia and some other parts of the world have been analyzed. Afterwards, investigation of the possible origin and pathways of introduction was done using analysis of haplotype networks based on the Cyt b gene. The results revealed that there are three introduced species i.e., Carassius auratus, Carassius gibelio and Carassius langsdorfii, in inland waters of Iran. Carassius langsdorfii was recorded from Iran and western Asia for the first time. Analysis of haplotype network showed various potential sources of introduction for each species in Iran and regions beyond their native distribution ranges. [ABSTRACT FROM AUTHOR]

Abstract: Freshwater fishes of the genus Carassius are widespread throughout Eurasia, but notoriously difficult for identification by morphological characters, leaving their systematics in a vague state and the validity of several species is unclear. Consequently, genetic data are used to identify the evolutionary units within this genus. Here, we present an analysis of the genus Carassius in Vietnam and south‐eastern China based on phylogenetic reconstruction using the mitochondrial cytochrome b gene and the nuclear S7 gene. We found two lineages in Vietnam with high supports in the nuclear as well as the mitochondrial dataset. One lineage corresponds to the species Carassius auratus, and one lineage represents an independent evolutionary unit. We test whether the lineage may correspond to the species that has once been described as Carassius argenteaphthalmus. The main character for identification, the color of the eye rim, did not distinguish two clades from each other. Considering the absence of genetic data, the imprecision of the original description, and the absence of all type specimens, the name of C. argenteaphthalmus is considered to be a nomen dubium. [ABSTRACT FROM AUTHOR]

Abstract: This study was designed to investigate effects of dietary Chlorella meal (CM) additive on growth performance, immune responses and appetite regulation of juvenile crucian carp Carassius auratus (initial body weight: 1.27 ± 0.03 g). Four experimental diets were formulated to contain 0% (CM0), 1% (CM1), 2% (CM2) and 4% Chlorella meal (CM4), respectively. Each diet was randomly assigned to triplicate groups with 40 juvenile fish per fibreglass tank for 8 weeks. Weight gain rate, specific growth rate and feed intake increased with increasing dietary CM levels. In contrast, FCR (feed conversion rate) declined with dietary CM levels. No significant differences were observed in moisture, crude protein, crude lipid and ash contents of muscle and liver tissues. Dietary CM addition increased activities of acid and alkaline phosphatase in liver and kidney. Dietary CM up‐regulated the mRNA expression levels of NKEF‐B, MCHII and IgM in kidney, and increased the mRNA levels of NPY and agouti gene‐related protein in the brain, but down‐regulated mRNA levels of MC4R, LEP, LEPR, CART1, CART2 and CCK8 genes. Based on these observations above, this study indicated that dietary CM additive increased growth performance, immune responses and appetite of crucian carp. The results, for the first time, demonstrate a role for the central nervous system in the control of food intake in fish fed dietary Chlorella meal. [ABSTRACT FROM AUTHOR]

Evolutionary trajectory and occurrence history of polyploidy have been extensively studied in plants, but they remain quite elusive in vertebrates. Here, we sampled and gathered 4,159 specimens of polyploid Carassius species complex including 1,336 tetraploids and 2,823 hexaploids from a large geographic scale (49 localities) across East Asia, and identified a huge number of 427 diverse haplotypes of mitochondrial control region, in which 74 haplotypes with total occurrence frequency up to 75.498% were shared by hexaploids and tetraploids. Significantly, these diverse haplotypes were clustered into four major lineages, and many haplotypes of hexaploids and tetraploids were intermixed in every lineage. Moreover, the evolutionary trajectory and occurrence history of four different lineages were revealed by a simplified time-calibrated phylogenetic tree, and their geographic distribution frequencies and haplotype diversity were also analyzed. Furthermore, lineage C and D were revealed to undergo population expansion throughout mainland China. Therefore, our current data indicate that hexaploids should undergo multiple independent polyploidy origins from sympatric tetraploids in the polyploid Carassius species complex across East Asia. [ABSTRACT FROM AUTHOR]

The pharmacokinetics and tissue residues of moroxydine hydrochloride were studied in gibel carp at water temperature of 15 and 25 °C. Samples (blood, skin, muscle, liver, and kidney) were collected over 10 days after the treatment and analyzed by high-performance liquid chromatography with an ultraviolet detector. The results indicated that the influence of water temperature on the metabolism of the drug was significant. The plasma concentration-time data of moroxydine hydrochloride conformed to single-compartment open model at the two water temperatures. There were higher absorption rate ( t1/2ka) and longer elimination half-lives ( t1/2ke) at 15 °C (4.29 and 15.87 h, respectively) compared with those at 25 °C (3.02 and 4.22 h, respectively). The maximum plasma concentration ( Cmax) and the time-point of maximum plasma concentration ( Tp) were 2.98 μg/mL and 10.35 h at 15 °C and 3.12 μg/mL and 4.03 h at 25 °C, respectively. The distribution volume ( Vd/ F) of moroxydine hydrochloride was estimated to be 4.55 L/kg at 15 °C and 2.89 L/kg at 25 °C. The total body clearance ( CLb) of moroxydine hydrochloride was determined to be 0.25 and 0.49 L/(h·kg) at 15 °C and 25 °C, respectively; the areas under the concentration-time curve were 75.89 μg·h/mL at 15 °C and 42.33 μg·h/mL at 25 °C. The depletion of moroxydine hydrochloride in gibel carp was slower with a longer half-life period, especially at lower water temperature that was tested. [ABSTRACT FROM AUTHOR]

Daidzein is widely used in farmed animals as a dietary additive. However, limited information is available about its use in aquaculture. The effects of daidzein inclusion in the diet of gibel carp was assessed in terms of growth performance, immune response, disease resistance, antioxidant activity, hormone levels, daidzein tissue residues, as well as intestinal and liver morphology. The dietary daidzein inclusion levels were 0, 40, 200 and 400 mg kg−1 and six replicates of 30 fish were used for each group. No mortality was observed during the 80 -day feeding trial. The growth performance of experimental fish was not significantly affected by dietary daidzein supplementation. However, the non-specific immune responses, resistance to Aeromonas hydrophila, antioxidant activities, 17β -oestradiol level, vitellogenin concentration, gonadosomatic index ( GSI) and intestinal morphology were significantly affected by dietary daidzein. A dietary dose of 400 mg kg−1 daidzein significantly decreased the GSI, increased 17β -oestradiol and vitellogenin concentrations, and impaired the intestinal structure. The daidzein residue in muscle of gibel carp was increased by the high level (400 mg kg−1) of dietary daidzein. Equol was not detected in fish muscle among all treatments. The present study proved that 40 mg kg−1 daidzein was safe to be included in diets of gibel carp, and a safety margin of 5 folds of the use-level (40 mg kg−1) was determined. [ABSTRACT FROM AUTHOR]

Epidemics caused by cyprinid herpesvirus 2 (Cy HV-2) in domestic cyprinid species have been reported in both European and Asian countries. Although the mechanisms remain unknown, acute Cy HV-2 infections generally result in high mortality, and the surviving carps become chronic carriers displaying no external clinical signs. In this study, in situ hybridization analysis showed that Cy HV-2 tended to infect peripheral blood cells during either acute or chronic infections in silver crucian carp, Carassius auratus gibelio (Bloch). Laboratory challenge experiments coupled with real-time PCR quantification assays further indicated that steady-state levels of the viral genomic copy number in fish serum exhibited a typical 'one-step' growth curve post-viral challenge. Transcriptional expression of open reading frames ( ORF) 121, which was selected due to its highest transcriptional levels in almost all tested tissues, was monitored to represent the replication kinetics of Cy HV-2 in peripheral blood cells. Similar kinetic curve of active viral gene transcription in blood cells was obtained as that of serum viral load, indicating that Cy HV-2 replicated in peripheral blood cells as well as in other well-characterized tissues. This study should pave the way for designing non-invasive and cost-effective serum diagnostic methods for quick detection of Cy HV-2 infection. [ABSTRACT FROM AUTHOR]

This study describes the effect of avermectin ( AVM) on the expression of γ-aminobutyric acid A receptor ( GABAAR) in Carassius gibelio. To assess the specific expression of GABAAR in the brain, gonads, liver, kidneys, heart, muscles, and skin of C. gibelio, the expression of GABAAR α1 subunit ( GABAAR α1) was measured by Western blotting. To study the effects of AVM on the expression of GABAAR, the median lethal concentration ( LC50) at 24, 48, and 96 h of AVM was determined and the expression of GABAAR in the brain, liver, and kidneys of the corresponding C. gibelio evaluated by Western blotting and immunohistochemistry. The results show that GABAAR was expressed in the brain, gonads, liver, kidneys, heart, intestines, muscles, and skin, while primarily distributed in the central nervous system and moderately distributed in peripheral tissues. The expression of GABAAR in the brain, liver, and kidney tissues of C. gibelio was increased with the treatment of AVM at 24 h LC50, but attenuated by the treatment of AVM at 48 h LC50 and 96 h LC50. This suggests a threshold effect of AVM. [ABSTRACT FROM AUTHOR]

Gillnet size selectivity was studied for freshwater fish species, based on experimental fishing trials carried out with multimesh gillnets in lentic freshwater systems in Northern Greece. Selectivity estimates were based on a large range of mesh sizes, i.e. more than 10 different mesh sizes ranging from 8 to 90 mm bar length. Results showed that the model, in which both mean and standard deviation of the curve were defined as a linear function of the mesh size, revealed the best fit. For seven (i.e. Α lburnus sp. Volvi, Aspius aspius, Carassius gibelio, Lepomis gibbosus, Pachychilon macedonicum, Squalius prespensis and Vimba melanops) of the 11 studied species and the hybrid ( Alburnus belvica × Rutilus prespensis), gillnet selectivity parameters were estimated for the first time, contributing to the evaluation of gillnet fisheries' impacts on fish species populations and consequently to fisheries management and species conservation. [ABSTRACT FROM AUTHOR]

European reservoirs are considered to be well characterized from many aspects. However, the description of long-term sequence of events in the fish fauna is restricted and mostly limited to deep, oligomictic reservoirs. Lake Hídvégi is a shallow hypertrophic reservoir (average depth = 1.14 m), which started to operate in 1985. The main function of this reservoir has been to retain nutrients carried by the River Zala in order to protect the water quality of Lake Balaton. The changes in the fish fauna of Lake Hídvégi was monitored in selected localities using standard method (electrofishing). Species composition and assemblage structure changed significantly during the study period, between 1986 and 2011. Following the inundation, the rapid expansion of gibel carp ( Carassius gibelio BLOCH, 1782) occurred, but after a peak this tendency turned. Surprisingly, based on the among-years variance of the relative abundances, most of the species were not affected seriously by the invasion. By the end of the studied period, the native generalist roach ( Rutilus rutilus L. 1758) became the most abundant species, amounting to more than 50% of the stock. By analyzing functional guilds, we identified an increasing trend in omnivore abundance, in parallel with the disappearance of planktivores. Our results suggest that the fish assemblage structure can be considered as metastable, disturbance tolerant and is mostly composed of generalist cyprinid species still after 29 years of operation. [ABSTRACT FROM AUTHOR]

In order to control saprolegniosis in Prussian carp ( Carassius gibelio (Bloch, 1782) eggs, it is important to screen herb extracts as potential anti- Saprolegnia drugs in Prussian carp hatcheries. For this purpose, an oomycete water mould (strain SC) isolated from Prussian carp [ Carassius gibelio (Bloch, 1782)] eggs suffering from saprolegniosis was characterised morphologically as well as from ITS rDNA sequence data. Initially identified as a Saprolegnia sp. based on its morphological features, the constructed phylogenetic tree using the neighbour joining method further indicated that the SC strain was closely related to Saprolegnia australis R. F. Elliott 1968 strain VI05733 (GenBank accession no. ), and which could form biofilm communities as virulence factors. In addition, aqueous extracts from forty Chinese herbs were screened as possible anti- Saprolegnia agents. Among them, a 1 g ml−1 extract from Radix sanguisorbae was the most efficacious anti- Saprolegnia agent, indicated by the minimum inhibitory concentration that was as low as 256 mg L−1. Relative survival of 73 and 88% was obtained against the SC strain in fish eggs at concentrations of 256 and 1280 mg L−1, respectively. This is the first known report of Saprolegnia australis R. F. Elliott 1968 infection in C. gibelio (Bloch, 1782) eggs involving the screening of R. sanguisorbae extracts as potential anti- Saprolegnia agents. [ABSTRACT FROM AUTHOR]

The original description of Myxobolus hearti is supplemented with new data on spore morphology, histopathology and molecular phylogeny. Myxobolus hearti are found in the heart ventricle of the gibel carp, Carassius gibelio (Bloch), where they form whitish oval or irregularly shaped plasmodia. Mature spores are oval or shortly ellipsoidal in frontal view, lemon-shaped in sutural view and eye-shaped in apical view. The spores are 14.12 ± 0.35 (13.6-15) μm long (mean ± SD), 11.85 ± 0.34 ± 0.36 (11-12) μm wide and 7.32 ± 0.36 (7-8) μm thick. The two polar capsules are equal in size, 6.11 ± 0.29 (6-7) μm long and 3.89 ± 0.31(3-4) μm wide, and are long pyriform in shape. Polar filaments have six or seven coils situated perpendicular to the longitudinal axis of the polar capsules. Histopathology indicates that the plasmodia are encased by the host connective tissue, and no inflammatory responses are found in the heart ventricles. Phylogenetic analysis based on the 18S small-subunit ribosomal DNA sequences indicates that M. hearti is, genetically, most similar to Henneguya doneci, a gill-infecting species. [ABSTRACT FROM AUTHOR]

In this study, records on the occurrence of the Japanese ginbuna Carassius langsdorfii from northern Germany, north-western Italy and southern Bosnia and Herzegovina are presented. The new findings, in addition to former studies reported in the Czech Republic and Greece, show that C. langsdorfii is much more widespread in Europe than was previously believed. [ABSTRACT FROM AUTHOR]

Hybrids of koi (an ornamental variant of the common carpCyprinus carpio) and goldfishCarassius auratus auratuswere produced by artificial spawning. All 3-year-old F1hybrid males examined were sterile, whereas some F1hybrid females were fertile and produced eggs after hormonal injection. Backcross progeny were obtained by using intact koi sperm to inseminate eggs from F1hybrid females; gynogenetic progeny were obtained by inseminating eggs from F1hybrid females with koi sperm that was genetically inactivated by ultraviolet irradiation. Flow cytometric analysis of DNA content indicated that the backcross progeny were triploid, while the gynogenetic progeny, pure koi, pure goldfish, and F1hybrids were all diploid. The triploidy of backcross progeny obtained without application of any treatment to the eggs demonstrates that the koi × goldfish hybrid females produce diploid eggs. Received November 11, 2011; accepted February 18, 2012 [ABSTRACT FROM PUBLISHER]

ABSTRACT Teleost fish scale is a dermal skeleton equipped with a strong regenerative ability. Owing to this regenerative ability, teleost fish scale can be used as a model for the regeneration of the dermal skeleton. However, there is insufficient fundamental knowledge of the regeneration, and this limits the usage of fish scale. In this study, as a first step toward understanding the molecular mechanism of the cellular differentiation during scale regeneration, we cloned the cDNAs for osteoblast-related proteins (Runx2, Sparc, and Bgp) in goldfish, and analyzed their expressions during scale regeneration. The expression profiles of these genes during scale regeneration were similar to those during mammalian osteoblastic differentiation. Specifically, runx2 expression was increased at the earliest time point, followed by sparc expression and then bgp expression. In the earlier stages, these genes were expressed in cells that formed cellular condensations and the flat cells surrounding them in the scale pocket. As the regeneration proceeded, the expressions became restricted to the episquamal, hyposquamal, and marginal scleroblasts and the cells around the marginal area of the regenerating scale. These results strongly suggest that (1) the differentiation mechanism of scleroblasts is similar to that of mammalian osteoblasts and odontoblasts, (2) scleroblast differentiation occurs around the cellular condensations at the early regeneration stage and is restricted to the marginal area of the scale at the later stage, and (3) the differentiation mechanisms are similar between the episquamal scleroblasts that produce the external layer and the hyposquamal scleroblasts that produce the basal plate. J. Exp. Zool. (Mol. Dev. Evol.) 318:190-198, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Gibel carp, Carassius gibelio (Bloch), impacts on native fish species have been reported but little studied despite a long history of introductions in Europe. This species is able to reproduce gynogenetically, which involves the use of sperm from males of other species to activate egg development, so reproductive competition is a likely but virtually unstudied impact of gibel carp on native fishes. This study evaluates the impact of introduced C. gibelio on the population biology of native fishes over a 6-year period in a mesotrophic drinking water reservoir in north-western Turkey. A dramatic decrease in the relative density (i.e. catch per unit effort) of native species correlated significantly with an increase in C. gibelio relative density. Growth characteristics (back-calculated ages, growth index and relative condition) and length at maturity did not differ significantly among years in C. gibelio and native fishes. Relative density, duration of spawning, reproductive effort and gonado-somatic index of C. gibelio increased with some water quality variables [total phosphorus (TP); chlorophyll- a (Chl- a)] and coincided with decreasing trends for natives. However, TP and Chl- a were not correlated with growth features in C. gibelio or natives fishes. The results suggest that the decline in the reservoir's native cyprinid populations is likely due to a combination of degrading environmental conditions and a disparity in reproductive effort, with introduced C. gibelio invasion facilitated by gynogenetic reproduction and an observed interference with native fishes during spawning. [ABSTRACT FROM AUTHOR]

The underlying mechanisms responsible for ecological plasticity and consequent invasive character of non-native freshwater fish species, variations in growth and life history traits in gibel carp Carassius gibelio (Bloch) were compared in natural and artificial water bodies of Turkey. Females significantly outnumbered males in all natural and most artificial waters. Discriminate function analysis differentiated gibel populations into three separate groups (natural lakes, artificial water bodies and running waters), with significant differences among separated groups in growth index, standard length and age at maturity, relative fecundity and gonado-somatic index, but not in egg diameter and both generalised and relative condition. Growth features (e.g. growth index and relative condition) and reproductive features (e.g. relative and absolute fecundity) positively correlated with water body area. No correlations were found for any growth or life history trait with depth, latitude and altitude. With the exception of smaller size at maturity, all traits were higher in populations from artificial water bodies than those inhabiting running waters, suggesting gibel carp is required to exert more reproductive effort to invade natural ecosystems than artificial waters. [ABSTRACT FROM AUTHOR]

A reduction of epidermal club cells and an increase of goblet cells were found in Carassius gibelio during spawning when compared to postspawning. A significantly lower proportion of club cells at spawning was found in diploid males and triploid females than in diploid females. It could be linked to male efforts to avoid a fright reaction and the potential adoption of this strategy by gynogenetic females, or alternatively to a higher parasite infection or immunosuppression during spawning. [ABSTRACT FROM AUTHOR]

The gynogenetic population of Prussian carp Carassius gibelio in Lake Pamvotis (north-west Greece) included a small percentage of males (2–3%). Cytogenetic analysis revealed heterogeneity of the population at the ploidy level: all females were triploid (modal chromosome number 156–162 chromosomes) while the males were either triploid (modal number 156–158 chromosomes) or tetraploid (modal number 200–214 chromosomes). Morphometric analysis revealed significant differences in body shape among these three groups. The males were more slender than females, while the triploid males could be discriminated from the tetraploid by the morphology of their caudal peduncle. The males attained a significantly lower asymptotic standard length ( LS) (25·04 cm) than females (29·75 cm) and had lower exponent b of the LS and mass relationship. Under laboratory conditions, intraspecific crossings of C. gibelio males with females could give viable all-female offspring; in comparison with goldfish Carassius auratus males, the fertility of the C. gibelio males was generally reduced but remained highly variable among individuals. [ABSTRACT FROM AUTHOR]

The article presents a study which identifies the estimated risk associated with cyanobacteria Microcystins (MCYST) in 13 lakes in Greece. It analyzes the MCYST distribution in water and its bio-accumulations on the tissues of Carassius gibelio fish. It reports that MCYST can endanger the health of livestock, fish, and humans in different exposure routes. The study has collected several fish and examined water samples from the lakes. It adds that MCYST were analyzed through water dissolving and cell-binding in suspended matter. It also emphasizes the importance of using general linear model (GLM) in assessing the differences between lakes and tissues relative to MCYST concentrations.

Three morphologically and genetically distinct forms of the genus Carassius were collected from the Ob River system, Kazakhstan, Central Asia; Carassius carassius, Carassius gibelio gibelio and an unknown stock tentatively referred to as Carassius gibelio sub-species M. The last mentioned had 33–41 gill rakers, being intermediate between the other two forms (23–27 in C. carassius and 44–49 in C. g. gibelio), and five scales in the upper transverse series, less than in the others. It also had a relatively larger erythrocyte suggesting triploidy and an mtDNA haplotype distinct from all other known crucian carps. Comparative mtDNA phylogenetic analysis suggested that C. gibelio gibelio in the Ob River system was introduced from China and the Amur River, the same possibly being true for European C. gibelio gibelio based on published haplotypes. C. gibelio sub-species M is thought to be more widely distributed in central Asia, probably extending as far west as European Russia. [ABSTRACT FROM AUTHOR]

Wild-captured 16 diploid, five triploid and one tetraploid Prussian carp Carassius gibelio males produced motile haploid, aneuploid (1·5n) and haploid to aneuploid (> 2n) sperm, respectively, in similar concentration and with the lowest percentage of live spermatozoa in sperm for the tetraploid male (mean ±s.d. 83·03 ± 1·76%; P < 0·05) compared to diploid and triploid males (97·37 ± 1·11% and 96·70 ± 1·45%; P > 0·05). [ABSTRACT FROM AUTHOR]

Lake Pamvotis is a tertiary natural shallow lake located in the NW of Greece. For biogeographical reasons, it historically contained only four fish species: two endemics ( Phoxinellus epiroticus, Squalius pamvoticus), one native to the West Greece ( Barbus albanicus) and the ubiquitous Anguilla anguilla. These species were almost exclusively present in the lake before 1920, forming remarkable commercially exploited populations. From the 1930s through the 1990s, 20 species were introduced into the lake for purposes of eutrophication control or to enhance the fishery. These introductions, some of them accidental have led to the apparent decline, even loss, of the native species. During the last three decades the fish fauna of the lake has shifted from the native, clear-water species to a predominance of introduced species, mainly those adapted for turbid eutrophic water ( Rutilus panosi, Cyprinus carpio and Carassius gibelio, and several Asian cyprinids). The current fish assemblage in the lake is dominated by introduced species particularly the Mosquitofish ( Gambusia affinis) and the Lourogobios ( Economidichthys pygmaeus) in the littoral zone, the benthopelagic allogynogenetic Prussian carp ( C. gibelio), and the opportunistic Trichonis roach ( R. panosi), in the pelagic zone. [ABSTRACT FROM AUTHOR]

Variation in three different clones of the invasive sperm-dependent, cyprinid fish Carassius gibelio were examined in Lake Pamvotis (north-west Greece). Differences between the clones were found in their proportion in the population, in their age structure, in the time of arrival to their spawning grounds and in the coefficients of the von Bertalanffy growth equation. [ABSTRACT FROM AUTHOR]

To evaluate the quality of reclaimed water, the estrogenicity of effluent from a sewage treatment plant and of reclaimed water treated with coagulation-sedimentation-filtration using the effluent as raw water was assessed using vitellogenin (VTG) as a biomarker. After a three-week exposure, significant (p < 0.05) induction of VTG occurred in female crucian carp (Carassius carassius) exposed continuously to the secondary effluent and reclaimed water with different dilutions (12.5, 25, 50, and 100% for secondary effluent; 50 and 100% for reclaimed water); no induction of VTG was detected when exposed to 12.5 and 25% reclaimed water. For male fish, however, only 100% secondary effluent induced the production of VTG (mean ± standard deviation, 38.6 ± 9.8 μg/ml). When the exposure time was prolonged to three months, VTG was induced significantly in both females and males at all gradient concentrations of secondary effluent and at 50 and 100% reclaimed water. The results indicated that no obvious VTG was detected in fish exposed to reclaimed water diluted more than fourfold. Ozonation of the secondary effluent under an ozone consumption dose of 8.5 mg/L resulted in a VTG level equal to that of 12.5% secondary effluent or 50% reclaimed water. Furthermore, VTG induction reflects the cumulative effects of estrogenic activity in the secondary effluent and reclaimed water compared with the in vitro assays, in which estrogenic activities in effluent changed markedly during the experiment. [ABSTRACT FROM AUTHOR]

The article provides information on a study about the growth, morphology and age-at-maturity of crucian carp Carassius carassius in Great Britain. The crucian carp Carassius carassius is threatened by the introduction of goldfish Carassius carassius through hybridization and by frequent misidentification of brown goldfish as crucian carp. The study showed that changes in morphological characters often associated with maturation suggest that age and size at that stage may reflect the size and age of active breeding.

The article presents the results of a study which investigated the mechanism by which microcystin-LR (MCLR) induces apoptosis in fish lymphocytes. Lymphocytes of the Carassius auratus fish were exposed in vitro to MCLR, which resulted in the elevation of reactive oxygen species and intracellular calcium, a decrease in adenosine triphosphate and rapid mitochondrial membrane potential disruption. The results are said to indicate that MCLR, the most toxic known microcystin, induces apoptosis by causing a massive calcium influx.

To investigate the response to starvation, gibel carp Carassius auratus gibelio [12.5 ± 0.03 g (mean ± SE, n = 24)] were deprived of food at 25.8 ± 0.2°C (mean ± SE, n = 56) for 56 days. Body mass, proximate composition in whole body and muscle, and respiration were measured at 7-day intervals. Body mass decreased with prolongation of deprivation, with a significant decline recorded after 7 days deprivation. Fish lost 22% of their fresh mass and 34% of dry mass after 56 days. Fish lost 38% of the body lipid over the first 7 days, and lost body lipid at a rate of 0–11% per week over the remaining 49 days. Body protein was lost at 1–5% per week throughout deprivation. Compared with the initial composition, body lipid concentration was lower and ash concentration higher on day 7. Water as a percentage of body mass was higher after 28 days, and protein concentration lower after 42 days, than at the start of deprivation. Muscle lipid and protein concentration was lower, and % water higher, after 7 days than at the start of deprivation, whereas muscle ash concentration was relatively constant during deprivation. After 56 days, fish lost body water by 18%, body lipid by 84%, body protein by 30%, and body energy by 45%. Oxygen consumption rate dropped from day 1 to day 3, increased from day 4 to day 14, gradually decreased from day 15 to day 35, and maintained a relatively constant level from day 36 to day 56. Results of the present experiment reveal that gibel carp utilize body lipid as a major energy source in the first 7 days of food deprivation, then turn to body protein as an energy fuel when lipid reserves are heavily depleted. Oxygen consumption is maintained at a relatively low and constant level when most lipid reserves are exhausted. [ABSTRACT FROM AUTHOR]

Morphological, cytogenetic and molecular genetic identification of two specimens of Carassius langsdorfii from the upper Elbe basin is given. Probably, the species was introduced by accident with commercial fish imports. Potentially, this introduced species may be of harm to native fish species. [ABSTRACT FROM AUTHOR]

A 11-week growth trial was conducted in a flow-through system with juvenile gibel carp Carassius auratus gibelio to evaluate the effects of gradual replacement of fish meal (FM) by meat and bone meal (MBM) on growth performance, phosphorus (P) and nitrogen (N) loading. Six isonitrogenous (crude protein: 410 g kg−1) and isoenergetic (gross energy: 18 kJ g−1) diets were formulated. FM was used as the control protein. In the other five diets, 20, 40, 60, 80 and 100% FM protein was substituted with MBM20, MBM40, MBM60, MBM80, MBM100, respectively. Total P content in the diets ranged from 16.0 to 28.3 g kg−1 and the available P was 5.0–6.6 g kg−1. The results showed that the best growth was achieved with fish fed on the control diet and MBM20. Final body weight, weight gain, feed efficiency, protein retention efficiency and energy retention efficiency decreased with increased dietary MBM. No significant differences were found in the feeding rate and hepatosomatic index between the groups. Apparent digestibility coefficient (ADC) of dry matter, protein and P decreased with increase in dietary MBM, while there were no significant differences in the ADC of energy. P and N retention decreased linearly while P and N loading increased linearly with the increased dietary MBM levels. No significant differences were observed in the activity of alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase, as well as pyruvate kinase in liver or in serum. Total superoxide dismutase activity in MBM20 was significantly higher than that of MBM100. [ABSTRACT FROM AUTHOR]

The length–weight relationships of the cyprinid fish Carassius gibelio (Bloch, 1782) are described for the 12 most important lakes of Greece. Carassius gibelio is an allogynogenetic fish species, which was introduced into Greek lakes during the late 1970s. The values of the exponent b of the length–weight relationships ranged from 2.33 to 3.38, and varied with the trophic state of the lake. In eutrophic lakes these b values were significantly (P < 0.001) lower than in oligotrophic or mesotrophic lakes. Relationships between the b values and phosphorus concentrations were logarithmic: b = 1.37–0.13 log (PO4-P); total length, fork length and standard length were linear (in all cases: r2 > 0.95). In most of the lakes, populations consisted of females, with the exception of Pamvotis, Doirani and Koronia lakes where a small proportion were males. [ABSTRACT FROM AUTHOR]

The effect of the replacement of fish protein hidrolizate and vitamin premix by freeze-dried biomass of the marine microalga Isochrysis galbana in the feed for goldfish ( Carassius auratus) larvae was tested. Larvae (3.4±0.7 mg) were fed with three experimental microparticulated diets that differ from each other in the percentage of replacement of fish protein hidrolizate (25% or 100%) or vitamin premix by I. galbana biomass. The control diet and the diet containing microalgae biomass as a substitute of 25% of fish protein hidrolizate (MP25) presented the highest survival, being almost 100%, with no significant differences between them. Survival in diets in which 100% of fish protein hidrolizate (MP100) or vitamin premix (MV) had been substituted by microalgal biomass was 78% and 66% respectively. Growth, measured as weight, was lower than with the control diet in all treatments in which microalgal biomass was included, with lowest results being obtained with the MP100 diet. Differences between treatments and control were lower when growth was measured as length. The harvesting and processing microalgae biomass is crucial to maintain the nutritive value and could be the cause for the obtained results. [ABSTRACT FROM AUTHOR]

A red-transparent population, distributed in Pingxiang of Jiangxi Province, was identified to be triploid Carassius auratus by DNA content measurement and chromosome analysis. Artificial propagation experiments indicated that the red-transparent triploid Carassius auratus could reproduce by gynogenesis. [ABSTRACT FROM AUTHOR]

Vøllestad LA, Varreng K, Poléo ABS. Body depth variation in crucian carp Carassius carassius: an experimental individual-based study. Ecology of Freshwater Fish 2004: 13: 197–202. © Blackwell Munksgaard, 2004 Induced morphological defences, where individuals develop morphological structures as a response to signals from sympatric predators, are common among invertebrates. Such defences have also been reported in a freshwater fish, the crucian carp Carassius carassius. In crucian carp, the presence of piscivorous fish presumably induces the development of a deep body as a defence mechanism. We tested how the growth rate (in body depth, length and mass) of individually tagged crucian carp responds to pike Esox lucius odours and control water. In general, crucian carp exposed to pike odour grew better (both in length and mass) than control fish. The treatment crucian carp also developed deeper bodies than control crucian carp. Further, there was a strong positive relationship between individual growth rate and the rate of change in body depth and this relationship did not differ between control and treatment fish. [ABSTRACT FROM AUTHOR]

Length-weight relationships of 13 fish species are presented from samples collected in the Ili River, northwestern China. This study provides the first description of length-weight relationships for five of the species. Coefficients of determination (r²) were >0.95 for 10 of the species. [ABSTRACT FROM AUTHOR]

Goldfish Carassius auratus L., larvae were raised on a diet of yeast, rice flour, vitamins and a lipid source consisting of 10% of either canola oil (CAN) or cod liver oil (COD) or a mixture of 5% of each (MIX). Survival of larvae raised on CAN or MIX diets was comparable to that of larvae raised on COD diets. In longer-term experiments, growth was superior and development more rapid in larvae receiving the COD diet. [ABSTRACT FROM AUTHOR]

The prevalence of acute and healed fin erosion in goldfish, Carassius auratus (L.). from the Waikato River, New Zealand, peaked in the vicinity of a pulp and paper mill which utilized a kraft pulping process in association with chlorine bleaching, and decreased down the effluent gradient. About 49% of goldfish sampled from the Kopakorahi Stream, which is part of the effluent treatment system (site 1), displayed pathological signs of fin erosion, whereas about 9% of control fish from a reference site located upstream of the official effluent discharge point were similarly affected. Fin erosion was less prevalent in male than in female goldfish, and occurred with different frequencies on different fins, the pectoral (56%) and caudal fins (33%) being most affected. Both the pectoral and caudal fins also had significantly higher proportions of healed erosion rather than acute erosion. The prevalence of acute and healed fin erosion increased significantly with increasing fish length (age). Physical deformities, predominantly in the form of eroded or otherwise malformed opercula, were found in nearly 5% of fish caught at site 1, but were not observed at the reference site. Changes in processing and bleaching technology at the pulp and paper mill in question have since been carried out, and long-term studies are planned to monitor any subsequent improvements in fish health. [ABSTRACT FROM AUTHOR]

An atypieal strain of Aeromonas salmonicida was isolated from goldfish, Carossius auratus L., with eutaneous uleerative lesions. Atlantic salmon, Salmo salar L., weighing 30-40 g were challenged parenterally and by bath immersion with this strain. It was found to be highly virulent in both forms of challenge and was capable of achieving an LD50 of three colony-forming units in parenterally challenged fish. The gross lesions and histopathology of infected fish bore a close resemblance to classical furunculosis in salmonids. Goldfish ulcer disease is endemic to some regions of Australia and represents a potential threat to the emerging salmonid farming industry. [ABSTRACT FROM AUTHOR]

1. The skull and weberian apparatus have been studied in 39 Indian, American and European cyprinine genera with a view to assess their usefulness in systematics. 2. A preethmoid is wanting in Esomus, Leuciscus, Phoxinus, Scardinius, Aristichthys and Notropis. A second preethmoid is a thin strut of cartilage; in Cyprinus, it is ossified. 3. The premaxillae exclude the maxillae from the gape of the mouth; the rostral limb of the premaxillae is absent in Diptychus and Ptyehidio. 4. The lateral ethmoid may be devoid of lateral processes. 5. The rostral is present in front of the ethmoid as a rod-shaped bone; it is attached by ligaments with the premaxillae, ethmoid and maxillae. In Danio, the rostral is horizontally expanded. 6. The supraorbital is always present showing size variation; in Labeo and Garra, it is short and in Ptyehidio, it is short and broad. 7. The orbitosphenoids are paired except in Cyprinus and Carassius where they are united. A median projection from the two orbitosphenoids may meet a similar projection from the parasphenoid to form an interorbital septum. 8. The posterior myodome is a spacious chamber in the basioccipital; anteriorly the chamber is bounded by the prootic and the parasphenoid. 9. The sphenotic does not form a part of the cranial roof, as the frontal meets the pterotic posteriorly; in Esomus, however, the sphenotic forms the roof and the sensory canal passes in it. 10. The supratemporal may be a triradiate or a simple tubular bone. 11. The supraoccipital does not roof the foramen magnum, the two exoccipitals send wings above the foramen to form the roof. 12. The subtemporal fossae are deep; the posttemporal fossae are poorly developed. 13. An opisthotic is noticed ventrally at the region the exoccipital and pterotic meet in Oreinus and Schizothorax. 14. The quadrate shows a posteriorly directed membranous extension which is laterally disposed; in Orienus, it is disposed medially to the adjacent bones. In Barilius the posterior process is very short. 15. The inferior pharyngeal bone (ceratobranchial 5) shows one row (Moapa, Eremichthys), two rows (Notropis, Eeuciscus) or three rows (Oreinus, Cyprinus) of teeth. 16. In the weberian apparatus, the tripus always shows a transformator process. The centra of the second and third vertebrae may sometimes be separate. The pleural ribs of the second and fourth vertebrae are always separate. 17. Since the cyprinine skull differs from that of Catostomus (Catostomidae) in many important characters, it is likely that the Catostomidae may not have given rise to the Cyprininae (Cyprinidae). 18. Since Moapa and Eremichthys, considered to be relict cyprinine genera, exhibit cranial characters similar to many other American minnows examined, they may not be ancient forms. [ABSTRACT FROM AUTHOR]

Abrupt pH changes from hatchery to pond water may affect survival of GoldfishCarassius auratusfry after stocking. A total of 12 triplicate pH treatments ranging from 3.57 to 11.50 were used to assess a gradient of abrupt pH changes on survival of 3-d posthatch (dph) Goldfish fry in aquaria during a 24-h exposure experiment. The experiment indicated that the 24-h LC10, LC50, and LC90 pH values for 3 dph Goldfish fry was 9.99, 10.52, and 11.08, respectively, based on an initial pH = 8.38. When pH was decreased below 8.38, the 24-h LC10, LC50, and LC90 occurred at a pH of 4.68, 4.27, and 3.89, respectively. Baitfish farmers should avoid pond water with high pH to reduce fry mortality during the early fry stocking period when the upper lethal pH limit (i.e., LC10, for practical consideration) of 9.99 will become possible. Received July 2, 2013; accepted August 30, 2013 [ABSTRACT FROM AUTHOR]

In this study, we isolated and characterized nine polymorphic trinucleotide microsatellites (CAG and CCT) from the crucian carp ( Carassius auratus). The number of alleles per locus ranged from two to six. Five loci showed a significantly excess homozygosity, and a genetic linkage between CAL0102 and CAL0495 was strongly suggested. Our results confirmed the triploidy of Korean individuals, and the microsatellites were found to be useful for analysing the allelic state of the polyploid crucian carp. [ABSTRACT FROM AUTHOR]

The present study reports length-weight relationships ( LWR) and length-length relationships ( LLR) for five native freshwater fish species ( Schizopygopsis younghusbandi, Triplophysa orientalis, T. tibetana, T. stewartii and T. stenura) and four introduced freshwater fish species ( Pseudorasbora parva, Carassius auratus, Micropercops cinctus and Oryzias latipes) captured in the Lhasa River Basin, Tibet, China. Five of the LWRs are presented for the first time. [ABSTRACT FROM AUTHOR]

The article provides information on the study concerning the detection of koi herpes virus in goldfish exposed to infected koi in the U.S. The koi herpes virus produces disease and high mortality in both wild and farmed koi and common carp. In addition, the virus is frequently spread through shipments of healthy-looking ornamental koi, but the potential carrier status of other fish species especially goldfish has been controversial. In the spring of 2006, American koi and goldfish dealer have suffered serious outbreak of koi herpesvirus (KHV) that caused high mortality of newly imported koi held in a static tank.

Focuses on shrinkage of preserved goldfish (Carassius auratus L.) larvae induced by formalin. Relationship between species and size and shrinkage, according to previous studies; Shrinkage of goldfish larvae in formalin over 36 hours.