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The present study was undertaken in order to assess the current status of ichthyofaunal diversity of one of Asia's largest freshwater lakes -- Wular, India. In this study the sampling was carried out every month at 5 different sites of Wular Lake which were selected on the basis of different ecological niches. A total of 738 fish species were collected during the entire study. The ichthyofaunal biodiversity observed in this study belonged to 2 orders, 2 families, 4 sub families and 6 genera. The carps viz. Cyprinus carpio (var. communis), Cyprinus carpio (var. specularis) and Carassius carassius contributed more than 82.52 % to the total catch by biomass and 50.79 % to the total catch by number. Shannon-Wiener diversity index showed maximum value (1.476) during summer and minimum value (1.195) during autumn. Similarly, Pielou's Evenness index and Simpson's dominance index also showed maximum values (0.856 and 0.645) in summer and minimum values (0.738 and 0.438) in autumn respectively. The study revealed that there was a drastic decline in the native Schizothorax due to encroachment, pollution and other anthropogenic disturbances. Many fish species that had been reported in the lake in the earlier studies were not reported in this study, indicating their disappearance from the lake. Keeping in view the progressively worse situation, there is an urgent need to take remedial steps to conserve the endangered native fish fauna of the lake in order to preserve its biodiversity from further degradation. [ABSTRACT FROM AUTHOR]

Genome duplication supplies raw genetic materials and has been thought to be essential for evolutionary innovation and ecological adaptation. Here, we select Kelch-like (klhl) genes to study the evolution of the duplicated genes in the polyploid Carassius complex, including amphidiploid C. auratus and amphitriploid C. gibelio. Phylogenetic, chromosomal location and read coverage analyses indicate that most of Carassius klhl genes exhibit a 2:1 relationship with zebrafish orthologs and confirm two rounds of polyploidy, an allotetraploidy followed by an autotriploidy, occurred during Carassius evolution. The lineage-specific expansion and biased retention/loss of klhl genes are also found in Carassius. Transcriptome analyses across eight adult tissues and seven embryogenesis stages reveal varied expression dominance and divergence between the two species. The expression of klhls in response to Carassius herpesvirus 2 infection shows different expression changes corresponding to distinct herpesvirus resistances in three C. gibelio gynogenetic clones. Finally, we find that most C. gibelio klhl genes possess three alleles except eight genes that have lost one or two alleles due to genome rearrangement. The allele expression bias is prosperous for Cgklhl genes and varies during embryogenesis owning to the sequential expression manner of the alleles. The current study provides global insights into the genomic and transcriptional evolution of duplicated genes in a given superfamily resulting from multiple rounds of polyploidization. [ABSTRACT FROM AUTHOR]

This study aimed to determine the length-weight relationship and condition factor of Prussian carp (Carassius gibelio, Bloch, 1782) from the Asi River. Samples were collected by 12-18 mm mesh sized fyke-nets between November and December 2021. Totally 88 specimens have been collected from the Turkish part of Asi River, Hatay, Türkiye. Lengths and weights ranged from 10.2 to 29.8 cm and 19.47 to 408.59 g, respectively. The b-values were calculated as 3.08 and the LWR equation was estimated as W = 0.0138*L3.08. The Fulton's condition factor (K) and the relative condition factor (Kn) values were calculated as 1.76±0.03 and 1.01±0.01, respectively. This study provides the valuable data on the length-weight relationship and condition factors of C. gibelio from the Asi River. The findings of the present paper revealed that C. gibelio showed an isometric growth and this region is relatively suitable for the growth of this species. Therefore, these data will be a valuable background for further biological studies and local fisheries management strategies. [ABSTRACT FROM AUTHOR]

This research was carried out to determine the effects of adding 0, 30, 60 and 120 mg/kg ginseng to the diets (T1, T2, T3 and T4) on growth performance and head development of goldfish. The trial was randomly divided into four groups, 30 goldfish in each group for 90 days. As a result of the research, it was determined that the addition of ginseng (60 and 120 mg/kg) to the diets (T3 and T4) significantly increased the specific growth rate, total live weight gains, head and body height of the fish compared with the fish fed with the control diet (T1) (P < 0.05) (P < 0.01). However, there was no positive effect on live weight gain, head height, and body height in fish fed the T2 diet. All ginseng feeds positively affected head widths, feed consumption, and feed efficiency of fish. On the other hand, in this study, the body lengths of the fish were not significantly affected by ginseng application. Especially because of the risk caused by the use of ginseng, it seems that 60 mg/kg ginseng can be used as an appropriate dose in goldfish. [ABSTRACT FROM AUTHOR]

Freshwater fishponds are an important part of the global aquaculture fish production, but they also are a source of invasive species with potentially negative impacts on pond ecosystems. In this study, we investigated dietary competition between common carp (Cyprinus carpio) and two invasive cyprinids, Pseudorasbora parva and Carassius gibelio , in fishponds of Central Europe. Using δ 13C and δ 15N stable isotopes analysis, we evaluated the extent of isotopic niche overlaps and the utilization of dietary sources by these species in fishponds that differ in the intensity of fish production. The isotopic niche of C. carpio and the invasive cyprinids overlap more in ponds with intensive (south-eastern Czechia) and semi-intensive (northern Austria) fish production then in ponds with low intensity production (eastern Slovakia). Our results also suggest that both invasive species opportunistically adjust their diet to their gape size and that they predominantly assimilate dietary energy from zooplankton and macroinvertebrates rather than from primary producers and detritus. Our study highlights the high potential of these invasive cyprinids to compete with C. carpio in fishponds of Central Europe. • Study of dietary overlap between common carp and invasive cyprinids in fishponds. • Isotopic niche overlap is higher in intensive and semi-intensive fishponds. • Low production intensity ponds show less dietary competition and niche overlap. • Invasive cyprinids in fishponds mainly consume zooplankton and macroinvertebrates. • Invasive cyprinids can have negative impacts on fishpond ecosystem and production. [ABSTRACT FROM AUTHOR]

Copyright of Erzincan University Journal of Science & Technology is the property of Erzincan Binali Yildirim Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Invasive freshwater fish species are considered a global threat to freshwater biodiversity and one of the leading factors responsible for species extinction. The freshwater species of genus Carassius are dispersed either naturally or due to human activities almost around the globe. The species identification in this genus using conventional morphological approaches bring up so many ambiguities because of high morphological similarities between the species, while taxonomic information is necessary prior to any biological study specifically when it comes to invasive alien species. The present study aims to delimitate two genetically identified Carassius species (Carassius gibelio and C. auratus) in some important freshwater ecosystems in Iran, which could be useful for early detection of species and discuss the reliability of the outcomes. For this purpose, morphometric and meristic variables were analyzed using Principal Component Analysis and one-way ANOVA analyses. The results showed significant differentiation between the surveyed individuals for each of the mentioned species. Despite this clear separation, there are factors such as ploidy level, hybridization and environmental-mediated morphological plasticity, which can put the results into the challenge. Consequently, several considerations need to be taken into account when dealing with morphological studies in the genus Carassius. [ABSTRACT FROM AUTHOR]

Background. Invasive gibel carp, Carassius gibelio (Bloch, 1782) has become well-established in the Hungarian waters and now are spreading in the European waters. On major concern now is the potential hybridization between gibel carp and the other invasive species in the Carassius auratus complex (CAC), which may further accelerate the spread of the whole invasive species complex. The identification of gibel carp and their hybrids is difficult because of its morphological similarity to the other species in CAC. Here we carry out a genomic assessment to understand the history of gibel carp invasion and its phylogenetic relationship with the other species in CAC. Three loci of the mitochondrial genome (D-loop, CoI, Cytb) were used to determine the phylogenetic origin of individuals and relarionship among six gibel carp populations and the other species in the CAC. Methodolgy. A total of 132 gibel carp samples from six locations in Southern Transdanubia (Hungary) were collected after phenotypic identification to measure the genetic diversity within and among gibel carp populations of Southern Transdanubia (Hungary). The genetic background was examined by the sequences of the mitochondrial genome: D-loop, Cytochrome c oxidase I (CoI) and Cytochrome b (Cytb). Mitochondrial genetic markers are excellent tools for phylogenetic studies because they are maternally inherited. Successfully identified haplotypes were aligned and with reference sequences in nucleotide databases (i.e., NCBI-BLAST: National Centre for Biotechnology Information and BOLD: Barcode of Life Data System). The phylogenetic relationships among gibel carp populations were then analyzed together with the reference sequences to understand the relationship and the level of hybridization with the species in CAC. Results. Among the 132 aligned D-loop sequences 22 haplotypes were identified. Further examination of representative individuals of the 22 haplotypes, six Cytb and four CoI sequences were detected. The largest number of haplotypes of all three loci were found in Lake Balaton, the largest shallow lake in Central Europe. Based on the NCBI-BLAST alignment of the D-loop, haplotypes of Carassius auratus auratus and Carassius a. buergeri in CAC were identified in the C. gibelio samples. Further analysis of haplotypes with the other two mitochondrial markers confirmed the occurrence of intragenus hybridization of C. gibelio in the Hungarian waters. Conclusion. By using three mitochondrial markers (D-loop, Cytb, CoI), we genomically characterized a gibel carp-complex in Hungarian waters and assessed the C. gibelio phylogenetic status between them. Hybrid origin of locally invasive Carassius taxon was detected in Hungary. It points out that invasive species are not only present in Hungary but reproduce with each other in the waters, further accelerating their spread. [ABSTRACT FROM AUTHOR]

Ecologoparasitological research was done based on the helminths and helminth communities of the Prussian carp (Carassius gibelio (Bloch, 1782)) from the freshwater ecosystem of the Panicheri Reservoir, Aegean Water Basin, Bulgaria. As a result of the examined nine specimens of the Prussian carp, two species of helminths were found: Ligula intestinalis (Linnaeus, 1758), larvae and Pomphorhynchus laevis (Müller, 1776). The dominant structure of the helminth communities was determined. The Panicheri Reservoir is a new habitat in Bulgaria of P. laevis and L. intestinalis from C. gibelio. C. gibelio is a new host record for L. intestinalis in Bulgaria. The two helminth species are core species for the helminth communities of the examined species of the freshwater fish. P. laevis was distinguished with higher prevalence and mean intensity (P%=33.34; MI=1.34) than L. intestinalis (P%=22.23; MI=1.0). The circulatory pathways of the helminth flow were traced. [ABSTRACT FROM AUTHOR]

Background Invasive gibel carp, Carassius gibelio (Bloch, 1782) has become well-established in the Hungarian waters and now are spreading in the European waters. On major concern now is the potential hybridization between gibel carp and the other invasive species in the Carassius auratus complex (CAC), which may further accelerate the spread of the whole invasive species complex. The identification of gibel carp and their hybrids is difficult because of its morphological similarity to the other species in CAC. Here we carry out a genomic assessment to understand the history of gibel carp invasion and its phylogenetic relationship with the other species in CAC. Three loci of the mitochondrial genome (D-loop, CoI, Cytb) were used to determine the phylogenetic origin of individuals and relarionship among six gibel carp populations and the other species in the CAC. Methodolgy A total of 132 gibel carp samples from six locations in Southern Transdanubia (Hungary) were collected after phenotypic identification to measure the genetic diversity within and among gibel carp populations of Southern Transdanubia (Hungary). The genetic background was examined by the sequences of the mitochondrial genome: D-loop, Cytochrome c oxidase I (CoI) and Cytochrome b (Cytb). Mitochondrial genetic markers are excellent tools for phylogenetic studies because they are maternally inherited. Successfully identified haplotypes were aligned and with reference sequences in nucleotide databases (i.e., NCBI-BLAST: National Centre for Biotechnology Information and BOLD: Barcode of Life Data System). The phylogenetic relationships among gibel carp populations were then analyzed together with the reference sequences to understand the relationship and the level of hybridization with the species in CAC. Results Among the 132 aligned D-loop sequences 22 haplotypes were identified. Further examination of representative individuals of the 22 haplotypes, six Cytb and four CoI sequences were detected. The largest number of haplotypes of all three loci were found in Lake Balaton, the largest shallow lake in Central Europe. Based on the NCBI-BLAST alignment of the D-loop, haplotypes of Carassius auratus auratus and Carassius a. buergeri in CAC were identified in the C. gibelio samples. Further analysis of haplotypes with the other two mitochondrial markers confirmed the occurrence of intragenus hybridization of C. gibelio in the Hungarian waters. Conclusion By using three mitochondrial markers (D-loop, Cytb, CoI), we genomically characterized a gibel carp-complex in Hungarian waters and assessed the C. gibelio phylogenetic status between them. Hybrid origin of locally invasive Carassius taxon was detected in Hungary. It points out that invasive species are not only present in Hungary but reproduce with each other in the waters, further accelerating their spread.

Information about ploidy is important in both commercial and conservation aquaculture and fish research. Unfortunately, methods for its determination, such as karyology, determination of the amount of DNA in a cell using microdensitometry or flow cytometry and/or measuring erythrocytes in a blood smear can be stressful or even destructive. Some of these methods are also limited by the relatively large minimum size of the individual being measured. The aim of this study was to test a new low-stress method of determining ploidy by measuring the size of erythrocytes in the capillaries of a fish, including small individuals. First, we examined diploid and triploid loach (Cobitis sp.) and gibel carp, Carassius gibelio (Bloch, 1782), using flow cytometry and blood smears, with these results being used as a control. Subsequently, we measured the size of erythrocytes in the caudal fin capillaries of anesthetized fishes of known ploidy under a light microscope. For both the loaches and gibel carp, direct observation of the mean erythrocyte size in epithelial fin capillaries provided a consistent and reliable determination of ploidy when compared with the controls based on flow cytometry and blood smears. This new method allows for rapid determination of ploidy in living small fish, where collection of tissue using other methods may cause excessive stress or damage. The method outlined here simply requires the measurement of erythrocytes directly in the bloodstream of a live fish, thereby making it possible to determine ploidy without the need for blood sampling. The method described is sufficiently efficient, less demanding on equipment than many other procedures, can be used by relatively inexperienced personnel and has benefits as regards animal welfare, which is especially important for fish production facilities or when dealing with rare or endangered species. [ABSTRACT FROM AUTHOR]

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]

In February 2020, the nematode Philometroides sanguineus was detected in Carassius gibelio collected from Razim Lake and sold for human consumption at a fish market in Bucharest. Along with a parasitological examination, biometric information for the sample of Prussian carp was recorded. The features of philometrid adult females on their host were compared with similar studies. The size, body color, location site of attachment and seasonality of parasite occurrence were in agreement with previous reports of this nematode species. Also, a review of scientific and grey databases concerning species of Philometra Costa, 1845 and Philometroides Yamaguti, 1935 genera parasitising ichthyofauna of Romania was made. To our knowledge, after the source provided by Cojocaru (2010) this paper highlights for the second time in Romanian parasitological literature the use of scientific name Philometroides sanguineus. However, the adopted synonyms and the site of infection recorded by other authors suggest an earlier presence of this helminth species in gibel (Prussian) and crucian carps from various freshwater resources of Romania. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hydrobiology is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An allozyme analysis of five sets of polymorphic loci of the gynogenetic Prussian carp C. gibelio from Northern Ukraine made it possible to identify within this species 29 genetic forms of clonal and recombinant nature, which can be divided into two categories. The first one is represented by the clonal C. gibelio-1 biotype with the modal number of 156 chromosomes and several unique alleles, which distinctly differentiate this biotype from the diploid goldfish C. auratus. The second category is represented by the group of 28 biotypes designated as C. gibelio-2 of a clonal and recombinant nature. Specimens of this group have no allozymes that distinguish them from C. auratus. Within this group, 158 and 160 modal chromosome groups were discovered; each one has special genotypic combination for locus Aat-1. Apparently, the series of biotypes, which are differentiated by the modal chromosome number, emerged independently as a result of hybridization of different pairs of parental species way back in Eastern Asia. At the same time, the emergence of recombinant individuals with unique combinations of genotypes of five protein loci and their own chromosome number within the C. gibelio-2 clone is a secondary event related to the implementation of the inheritance mechanism, which combines cloning and Mendelian inheritance. There are reasons to believe that this mechanism is implemented in pseudogamous crosses of genetically close C. gibelio-2 females with C. auratus males, while the cloning takes place in crosses of C. gibelio-2 females with more distant C. carassius males. [ABSTRACT FROM AUTHOR]

The oxidative status of the hepatopancreas of Prussian carp females (Carassius gibelio) co-exposed to sublethal cadmium in water and melatonin was studied. The activities of antioxidant enzymes such as glutathione reductase (GR), glutathione peroxidase (GPx), and superoxide dismutase (SOD) as well as the concentration of reduced glutathione (GSH) were measured in homogenates of the hepatopancreas. Furthermore, concentrations of cadmium (Cd), zinc (Zn), copper (Cu), and iron (Fe) in the hepatopancreas were assayed. These females received melatonin implants and were exposed to 0.4 mg/L or 4.0 mg/L Cd in water for either a 13- or a 7-week period, followed by further 6 weeks of purification in clear water. Exposure to Cd influenced the increase in this metal concentration in fish hepatopancreas. In contrast, the fish exposed to cadmium with additional administration of melatonin had a lower accumulation of this metal. Exposure to Cd caused the increase in GSH content and the activity of GR, and a reduction in GPx activity, whereas the SOD activity varies depending on the exposure time on cadmium. In the hepatopancreas of fish treated with Cd alone, the content of Cu and Zn were increased and that of Fe was changed. After melatonin administration to Cd-exposed fish, a decrease in copper and zinc hepatopancreas content was noted. The present findings imply that melatonin co-treatment can effectively protect the fish against the toxic effects of cadmium on endogenous antioxidant status in hepatopancreas tissues and variations in metal concentration, such as Zn, Cu, and Fe. [ABSTRACT FROM AUTHOR]

Abstract The effects of guar gum, when used as a feed binder, on growth performance, digestive enzyme activity, and intestinal histology in gibel carp were evaluated. Four isonitrogenous and isoenergetic diets were formulated and supplemented with 0%, 1%, 3%, and 5% guar gum. The different diets were fed to triplicate groups of gibel carp (mean initial weight: 5.60 ± 0.003 g) for 51 d. Feed supplemented with 1% guar gum had no effect on specific growth rate, feed efficiency, condition factor, or protein retention efficiency as compared to the control group; this level of supplementation increased microvillus length in the distal intestine and increased fecal viscosity. In contrast, 5% guar gum supplementation increased feed hardness, decreased feed water solubility, and decreased total nitrogen content in the soaking water after 3-h immersion. However, 5% guar gum supplementation decreased feed intake and induced distal intestine damage, as indicated by shorter microvilli as compared to the control group. Supplementation with 5% guar gum also decreased the activity levels of intestinal digestive enzymes (chymotrypsin, amylase, and alkaline phosphatase) and decreased plasma total cholesterol and triglycerides, and finally reduced fish growth. Dietary supplementation with 1% guar gum increased fecal viscosity sufficiently to decrease water pollution, without significant adverse effects on growth performance, feed utilization, and intestinal microstructure in the gibel carp. Highlights • Diets supplemented with 5% guar gum decreased gibel carp growth. • Diets supplemented with 5% guar gum damaged gibel carp intestinal structure. • Optimal guar gum supplementation level in the gibel carp was 1%. [ABSTRACT FROM AUTHOR]

Abstract To explore the effect of light intensity on phototaxis, growth performance and physiological condition of juvenile gibel carp, a short-term ethological experiment and a long-term cultivation experiment were carried out. Light intensity generated by white light emitting diodes (LEDs) was graded during the whole experiment. In the ethological experiment, juvenile gibel carp (5.00 ± 0.02 g) were exposed to light intensities of 0, 0.03, 0.09, 0.24, 0.56 and 1.06 μmol·m−2·s−1 in a 6-cell behavior study facility. Gibel carp exhibited negative phototaxis in the short-term ethological experiment. In the long-term cultivation experiment, juvenile gibel carp (5.20 ± 0.05 g) were cultured under seven illumination levels (0, 0.03, 0.24, 1.08, 4.7, 9.46, 19.36 μmol·m−2·s−1 in bottom water at a 0.5-m water depth) in an indoor recirculation water system for 70 days. The fish were fed to satiation three times daily (8:30, 14:30 and 18:30). The photoperiod was 12 L:12D (8:00–20:00). The results showed that the best growth of juvenile gibel carp were observed at 0.03–1.08 μmol·m−2·s−1. The hepatopancreas oxidative stress of juvenile gibel carp were induced in a dark environment (0 μmol·m−2·s−1); plasma cortisol, glucose and lactic acid increased significantly when the light intensity increased to 9.46 μmol·m−2·s−1. Based on the quadratic regression analysis of specific growth rate, the optimal light intensity for juvenile gibel carp was 0.39 μmol·m−2·s−1. Highlights • Short-term ethology and long-term cultivation experiment were carried out to explore the effect of light on gibel carp. • Gibel carp exhibited negative phototaxis in the short-term ethological experiment. • The hepatopancreas oxidative stress of gibel carp was induced in a dark environment. • Gibel carp reared in a high light environment suffered a high degree of stress. • The optimal light intensity for juvenile gibel carp cultivation was at 0.39 μmol·m−2·s−1. [ABSTRACT FROM AUTHOR]

Effects of sex and age on fatty acids profile in the meat of Carassius spp. were evaluated. Carassius auratus fillets displayed a higher content of SFA and MUFA than Carassius carassius. In contrast, Carassius carassius had a higher content of PUFA (higher proportion of linoleic, arachidonic, eicosapentaenoic, docosatetraenoic and docosapentaenoic acids) and total n-3 and n-6 PUFA, compared with Carassius auratus. Moreover, γ-linolenic acid was higher in fillets from Carassius auratus. What is more, fillets from females had a greater content of eicosapentaenoic acid than males. Finally, 4-year-old fish had a lower content of ALA, higher MUFA content and better nutritional indexes (n-3/n-6, AI) than 3-year-old fish. [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]

Lead (Pb) poisoning in humans and fish represents a significant global problem. Bacillus subtilis ( B. subtilis ) is a widely used probiotic in aquaculture. Carassius auratus gibelio ( C. gibelio ) is one of the most important aquaculture species with great commercial value. The objective of this study was to evaluate the potential of B. subtilis in ameliorating lead-induced toxicity in C. gibelio . The fish were exposed for 60 days to waterborne Pb at 0, 0.05, 0.5 and 1 mg/L and/or dietary B. subtilis at 10 9 cfu/g. After 30 and 60 days, the fish were sampled and bioaccumulation, antioxidant activity and immune responses were assessed. The results revealed that B. subtilis confers significant protective effects against lead toxicity by preventing alterations in the levels of bioaccumulation, superoxide dismutase, catalase and glutathione. B. subtilis also assists in the recovery of blood δ-aminolevulinic acid dehydratase, lysozyme, and IgM levels while regulating the expression of immune-related genes including IL-10, lysozyme, TNF-α, IgM and Hsp70 after 60 days of lead exposure. Our results suggest that administration of B. subtilis (10 9 cfu/g) has the potential to combat lead toxicity in C. gibelio . [ABSTRACT FROM AUTHOR]

Autotetraploids fish (4nRR) (4n = 200, AAAA) were resulted from the whole-genome duplication of Carassius auratus red var. (RCC) (2n = 100, AA). Following activation by UV-irradiated Megalobrama amblycephala (BSB) sperm, the autodiploid eggs (2n = 100, AA) of 4nRR females developed into all-female autodiploid gynogenetic offspring (G 1 ) (2n = 100, AA) without chromosome doubling treatment, indicating an XXXX genotype of the female autotetraploids. Compared with 4nRR and RCC, G 1 individuals matured after 2 years, suggesting obviously delayed maturity. Tetraploid offspring (4nRG) (4n = 200) were also produced by crossing G 1 females with male autotetraploids, suggesting that G 1 individuals can produce unreduced eggs (2n = 100). After activation by UV-irradiated BSB sperm, the fertilized eggs of G 1 females developed into a second generation of autodiploid gynogenetic offspring (G 2 ) (2n = 100, AA) without chromosome doubling treatment. The diploid gametes are an important gamete source for the production of polyploid fish and the establishment of a diploid gynogenetic clone line, which will be useful for genetic analyses and breeding. [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]

We compared the glucose clearance ability of gibel carp CAS III (A strain) with gibel carp Dongting (DT strain). A previous study suggested that these two strains responded to insulin differently. As insulin plays an important role in glucose utilization, we hypothesized that the ability to eliminate excess glucose after a glucose load would differ between A strain and DT strain. To test this hypothesis, fasted specimens of both strains of gibel carp were injected with glucose. As expected, glucose induced hyperglycemia in both A strain and DT strain. In both strains, mRNA levels of the glycolytic enzyme 6-phosphofructokinase (6PFK) increased in the white skeletal muscle 8 h post-injection, while expression levels of glucose-6-phosphatase (G6Pase), fructose 1,6-bisphosphatase (FBPase), and phosphoenolpyruvate carboxykinase (PEPCK) decreased in the liver 8 h post-injection. In the DT strain, both GLUT4 expression and muscular glycolytic processes increased, as reflected by elevated hexokinase 2 (HK2) and pyruvate kinase (PK) mRNA expression levels. The DT strain also returned to basal glycemia more quickly than the A strain (within 6 h versus more than 12 h). The glycogen concentration in the liver of the DT strain was higher than that of the A strain, indicating that the DT strain was better able to store glucose as glycogen than the A strain. Overall, the DT strain was better able to clear excess blood glucose after the glucose tolerance test than the A strain. [ABSTRACT FROM AUTHOR]

In various tissues ofLuciobarbus esocinus,Cyprinus carpio, andCarassius gibeliowhich were taken from Keban Dam Lake Pertek region’s freshwaters, Turkey in January–February 2016, concentrations of mercury, nickel, lead, cadmium, arsenic, manganese, chromium, and cobalt were analysed by inductively coupled plasma-mass spectrometry (ICP-MS) after microwave digestion. In fish muscle mean chromium concentration (0.614 mg kg−1inC. carpiomuscle) was higher than the maximum limits as set by the Federal Environmental Protection Agency and World Health Organisation. Additionally, mean concentration of lead (0.380 mg kg−1inC. gibeliomuscle) was higher compared to the maximum limit as set by Turkish Standards. Furthermore, in the assessment of the potential health risk, estimated weekly and daily intake of all metals were considerably below permissible tolerable weekly intake (PTWI) and permissible tolerable daily intake values. As a result, consumption of these fish species from this region does not pose a problem on human health. [ABSTRACT FROM PUBLISHER]

The crucian carp Carassius carassius (Linnaeus, 1758), is native to many European freshwaters. Despite its wide distribution, the crucian carp is declining in both the number and sizes of populations across much of its range. Here we studied 30 individuals of a putative pure population from Helsinki, Finland. Despite clear external morphological features of C. carassius, an individual was of a higher ploidy level than the others. We therefore applied a set of molecular genetic (S7 nuclear and cytochrome b mitochondrial genes) and cytogenetic tools (sequential fluorescent 4’, 6-diamidino-2-phenylindole [DAPI], Chromomycin A3 [CMA3], C-banding and in situ hybridization [FISH] with both 5S and 28S ribosomal DNA probes) to determine its origin. While all examined characteristics of a diploid representative male (CCAHe2Fi) clearly corresponded to those of C. carassius, a triploid individual (CCAHe1Fi) was more complex. Phylogenetic analysis revealed that the nuclear genome of CCAHe1Fi contained three haploid sets: two C. gibelio and one C. carassius. However the mitochondrial DNA was that of C. gibelio, demonstrating its hybrid origin. The FISH revealed three strong (more intensive) 5S rDNA loci, confirming the triploid status, and an additional 24 weak (less intensive) signals were observed in the chromosome complement of CCAHe1Fi. On the other hand, only two strong and 16 weak 5S rDNA signals were visible on the chromosomes of the CCAHe2Fi male. 28S rDNA FISH revealed four strong signals in both CCAHe1Fi and CCAHe2Fi individuals. CMA3 staining revealed four to six CMA3-positive bands of CCAHe1Fi, while that of diploids contained only two to four. The fact that a polyploid hybrid Carassius female with a strong invasive potential may share morphological characters typical for endangered C. carassius highlights a need to combine genetic investigations of Carassius cryptic diversity with conservation measures of C. carassius in Europe. [ABSTRACT FROM AUTHOR]

The present study, seasonal pollution of heavy metals (Pb, Cd, Cr and Cu) in water, sediment, tissues of fish Carassius carassius and oyster Crassostrea gigas were determined at seven sampling sites from Meiliang Bay, Taihu Lake during one year calendar, 2016. The total heavy metal concentrations in water samples were higher in winter and summer than in spring and autumn season, whereas in sediment they were higher in winter and summer seasons, respectively. The trend of metal mean contents found in the fish and oyster were in decreasing order of Pb > Cu > Cr > Cd and Pb > Cu > Cr > Cd, respectively. The tissues of fish and oyster captured during winter and summer accumulated a higher significant different amount of metals relative to other season, which was attributed to a higher influx of agricultural waste, sewage and sludge by heavy rainfall and floods. In addition, the pollution load index (PLI) values were above one (>1), indicating an advanced decline of the sediment quality, and contamination factor (CF) confirmed that the sediment samples were moderate to high contamination by Pb and Cr. Thus, comparative studies with seasonal pollution of heavy metals in Meiliang Bay of Lake Taihu regions indicate considerable heavy metal enrichment in water, sediments as well as in various organs of fish and oyster. Finally, our results indicated that the metal concentration values increased statistically significant different related to season (p < 0.001). The determination of heavy metal stress biomarkers in fish along with seasonal variations may serve as a convenient approach during pollution bio-monitoring programme. [ABSTRACT FROM AUTHOR]

The alien fish species Prussian or gibel carp (Carassius gibelio) was introduced to Croatia from Asia several decades ago. The analysis was performed by the official monitoring data from the Final Report for the Ministry of Agriculture of the Republic of Croatia by the Faculty of Agriculture, University of Zagreb during the last eight years (2010-2017) in combination with the statistical analysis of the fisheries data of the Krapina-Zagorje County and Sisak-Moslavina County in the period from 2004 to 2015. The proportion of Prussian carp catches (in kg) increased at Sisak-Moslavina County from 26.45% to 41.84% from 2004 to 2015, leading to a significant decrease of catches of common carp from 25.59% to 8.70%, respectively (r² = 0,936; p < 0,01). The catch per unit effort (CPUE) of Prussian carp, defined as annual catch by an average angler, significantly increased, from 6 kg at the beginning of this period to 14 kg at its end. These data show that Prussian carp still enlarges its populations along the Sava River. [ABSTRACT FROM AUTHOR]

Length-weight relationship, Fulton's K condition factor and the size structure were assessed for unsexed cyprinid gibel carp, Carassius gibelio (Bloch, 1782) (N= 100) caught from Pantelimon II Lake area - a man-made lake from Colentina River. Negative allometric growth was estimated for gibel carp in both seasons: TW = 0.0396 x TL2.7583 (N=50, November 2016) and TW = 0.0269 x TL2.8639 (N=50, May 2017). Condition factor K registered values between 1.44 and 2.38 (cold season), 1.49 and 3.79 (warm season). The physico-chemical parameters such as pH, electrical conductivity, total dissolved solids, total hardness, chemical oxygen demand, ammonium nitrogen, nitrite-nitrogen, nitrate nitrogen and phosphorus-phosphate were determined, in order to evaluate the impact of abiotic environmental conditions on fish population. The microbiological examination of water quality was also carried out, to detect the micromycetes which may pose health risk to both human and fish. The presence of Penicillium spp. and some yeast strains were confirmed in water samples from the studied area. According to all analyzed parameters, the water resource was found to be within the suitable range for well-being of C. gibelio, which is important assuming that local fishermen often catch and eat gibel carp. To our knowledge, this paper provides first information on length-weight relationship, Fulton's K condition factor and the size structure of Carassius gibelio from Pantelimon II Lake. [ABSTRACT FROM AUTHOR]

A major threat to gibel carp aquaculture is an epizootic disease caused by C. auratus herpesvirus (Ca HV). Therefore, breeding of disease resistant strain is one of significant needs for the industry. Polyploids often show enhanced tolerance to abiotic or biotic stress. However, the effects of WGD are complex and the underlying mechanisms remain elusive. In this study, we first synthesized a group of novel amphitetraploids via crossing the eggs of gynogenetic C. gibelio clone A+ with the trypsin-treated sperm of sexual C. cuvieri and then established three gynogenetic amphitetraploid clones with different transferrin phenotypes. They all showed intermediate resistance to Ca HV in relative to their parents. Subsequently, we uncovered distinct transcriptomic response to Ca HV infection in the one amphitetraploid clone (Ca A4n-I) compared with their parents. Interestingly, the coexpression gene network analysis showed that amphitetraploid Ca A4n-I and their paternal C. cuvieri adopted different anti-viral strategies via up-regulating the expression of positive factors or down-regulating the expression of negative factors in immune response respectively. Moreover, we revealed the complicated changes of expression patterns, including additivity, maternal expression level dominance, paternal expression level dominance, transgressive up-regulation, and transgressive down-regulation, in the amphitetraploid Ca A4n-I. After Ca HV infection, the proportions of maternal expression level dominance and transgressive up-regulation increased and more C. cuvieri -derived homeologous genes altered expression patterns in the amphitetraploid Ca A4n-I. The current study not only produces a candidate strain for C. auratus aquaculture, but also provides a transcriptomic picture how a newly synthetic animal allopolyploid to response to virus infection. • Ca A4n-I with higher resistance to Ca HV relative to maternal Cg -A+ was generated. • Distinct transcriptomic changes in response to Ca HV infection in three fish types. • Ca A4n-I and their paternal C. cuvieri adopted different anti-viral strategies. • Complex expression pattern changes were revealed in Ca A4n-I after Ca HV infection. [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]

Whole-brain responses to sound are easily measured through auditory evoked potentials (AEP), but it is unclear how differences in experimental parameters affect these responses. The effect of varying parameters is especially unclear in fish studies, the majority of which use simple sound types and then extrapolate to natural conditions. The current study investigated AEPs in goldfish ( Carassius auratus) using sounds of different durations (5, 10, and 20 ms) and frequencies (200, 500, 600 and 700 Hz) to test stimulus effects on latency and thresholds. We quantified differences in latency and threshold in comparison to a 10-ms test tone, a duration often used in AEP fish studies. Both response latency and threshold were significantly affected by stimulus duration, with latency patterning suggesting that AEP fires coincident with a decrease in stimulus strength. Response latency was also significantly affected by presentation frequency. These results show that stimulus type has important effects on AEP measures of hearing and call for clearer standards across different measures of AEP. Duration effects also suggest that AEP measures represent summed responses of duration-detecting neural circuit, but more effort is needed to understand the neural drivers of this commonly used technique. [ABSTRACT FROM AUTHOR]

Approximately three dozen Myxobolus spp. (Myxozoa: Myxosporea: Bivalvulida) have been described to parasitize the gills of carp of the genera Cyprinus and Carassius. Hitherto, these fish were often introduced to temperate waters worldwide as food and ornamental fish from Asia, their place of origin. The present study examined the myxosporean infection of seven common carp ( Cyprinus carpio) and seven Japanese silver crucian carp ( Carassius langsdorfii) collected from the Fushinogawa River around the university in Yamaguchi City, Japan, during the period April 2015 to October 2016. In total, four Myxobolus spp. were detected in the gill lamellae of Cy. carpio and Ca. langsdorfii, i.e., two species in each species of fish. The four species were characterized morphologically and genetically based on the 18S ribosomal RNA gene (rDNA). A new species, Myxobolus tanakai n. sp., from four individuals of Cy. carpio had an elongated pyriform spore (15.4-18.6 μm by 6.3-8.4 μm), resembling the spore shape of Myxobolus koi from Cy. carpio or Carassius auratus in Japan, China, and the USA, but bigger than it (13.2-15.6 μm by 6.6-7.8 μm). The new species formed a clade with M. koi but was distinct from any of the isolates of this species (nucleotide identities less than 98.6%). The second new species, Myxobolus paratoyamai n. sp., from a single Cy. carpio with its one prominent and one rudimentary polar capsule closely resembled the spore morphology of Myxobolus toyamai from Cy. carpio or Carassius gibelio in Japan, China, and the USA. However, the isolate formed a clade with Myxobolus longisporus from Cy. rubrofuscus in China rather than with M. toyamai isolates (nucleotide identities less than 97.9% with known species). Another new species, Myxobolus ginbuna n. sp., from two individuals of Ca. langsdorfii had similar-shaped spores to Myxobolus wulii, but the dimensions were smaller (11.7-13.9 μm by 8.5-9.8 μm vs. 17.6-18.5 μm by 8.9-10.0 μm). This new species formed a clade with M. wulii but was distinct from any of the M. wulii isolates from Ca. gibelio in China (nucleotide identities less than 99.1%). An additional species, Myxobolus pyramidis, from six individuals of Ca. langsdorfii was morphologically and genetically similar to the previous record from Ca. gibelio in China (99.6% nucleotide identity of the 18S rDNA). Two of these six individuals were mix-infected with M. ginbuna n. sp. This is a new host and geographical distribution record for M. pyramidis. [ABSTRACT FROM AUTHOR]

Carassius praecipuus, new species, is described from a hill stream in the upper Nam Ngum watershed in Mekong drainage in central Laos. It is distinguished from all congeners by the short dorsal fin, a small number of branched dorsal-fin rays, lateral line scales and gill rakers. It reaches sexual maturity around 70 mm SL. This is the first species of the genus discovered outside East and North Asia and Europe. The upper Nam Ngum watershed includes a part of the Plain of Jars, which had been hypothesised to have allowed the movement of a number of fish lineages between the rivers flowing to the Gulf of Tonkin and the Mekong drainage. [ABSTRACT FROM AUTHOR]

Study of population structure of crucian carps in the mixed forests zone of Northern Ukraine (characterized by ample diversity of unregulated aquatic systems) showed the presence of diploid C. carassius and C. auratus, triploid C. gibelio (represented by a series of clones), C. auratus x C. carassius diploid hybrids, and tetraploid hybrids between C. carassius and C. gibelio. The crucian carps of the region compared with those of more southern zones of Ukraine are characterized by numerical prevalence of unisexual form of C. gibelio, and relatively restricted hybridization of C. carassius and C. auratus. [ABSTRACT FROM AUTHOR]