Search

This study identified vitamin B12 compounds in traditional fermented Japanese seafoods, such as heshiko made with a mackerel, kusaya made with a flying fish, Akazukuri-shiokara made with a squid, and funazushi made with a crucian carp, using reversed-phase high-performance liquid chromatography and liquid chromatograph–tandem mass spectrometry. The vitamin B12 content of these fermented seafoods was approximately 4–13 µg/100 g wet weight, indicating that vitamin B12 is the predominant corrinoid in all seafoods tested. However, kusaya contained approximately 8% of inactive cobamides such as 2-methyladenylcobamide and 2-methylmercaptoadenylcobamide. In conclusion, these traditional fermented Japanese seafoods can be a source of vitamin B12. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of adding Brevibacillus laterosporus (B. laterosporus) PBC01 to aquarium water on water quality, including Aeromonas spp. counts, growth performance, digestive enzyme activities, and antioxidant activity of the crucian carp Carassius auratus. One hundred and twenty healthy crucian carp (13.56 ± 0.2 g) were reared for 56 days in four different treatments with three replications, as the control group (clean water) and three test groups with PBC01 at levels 5 × 103 CFU/ml, 5 × 104 CFU/ml, and 5 × 105 CFU/ml added to the rearing water. As a result, B. laterosporus in rearing water can lower the concentrations of nitrogen and the number of Aeromonas spp. to varying degrees. As the B. laterosporus concentration increased, the effect became more significant. Crucian carp reared in water supplemented with B. laterosporus showed marked growth performance in comparison with the control group. In addition, rearing water supplemented with B. laterosporus improved antioxidant status in the serum and liver of crucian carp, and increased the intestinal digestive enzyme activity. In conclusion, certain amounts of B. laterosporus PBC01 used as a probiotic supplement in the aquarium water can promote crucian carp growth and improve the health status of these fish. [ABSTRACT FROM AUTHOR]

In our previous study, transcriptomes of crucian carp were sequenced using 454 Sequencing, which generated many expressed sequence tag (EST) sequences that are useful to develop gene-based markers. In this study, from these ESTs, 5505 simple sequence repeats (SSRs) were identified, among which dinucleotide repeats (43.6 %) and AC/GT motifs (39.6 %) were the most frequent, followed by AAT/ATT (15.5 %). We designed 3932 primers with sufficient amplified flanking sequences. To verify the identified EST-SSRs, 500 primers were randomly selected for polymerase chain reaction (PCR), of which 408 (81.6 %) were successfully amplified, among which 151 (30.2 %) were polymorphic. These polymorphic markers were further surveyed among an F population. The results showed that 148 loci were informative in both parents, with segregation ratios of 1:1:1:1 (23, 15.5 %), 1:1 (59, 39.9 %), and 1:2:1 (66, 44.6 %). In addition, the general linear model (GLM) procedure in the SPSS software package was used to analyze the correlations between these 148 loci and two growth traits. Twelve loci were discovered to be significantly ( P < 0.05 or P < 0.01) associated with body weight (BW), and 13 loci were significantly ( P < 0.05 or P < 0.01) correlated with standard length (SL). Meanwhile, genotypes that favorably affect BW and SL traits were determined. Therefore, the EST-SSRs developed in this work may be useful in linkage map studies and for marker-assisted selection (MAS) in breeding programs of this species. [ABSTRACT FROM AUTHOR]

This study investigated the plasma biochemical profiles and gene expression levels of crucian carp Carassius carassius subjected to anesthetization with low-voltage constant direct current (DC) and tricaine methanesulfonate (MS222). Fish in the MS222 treatments and the DC treatments were exposed to either two concentrations of MS222 (100 and 200 mg/l) or constant DC with a voltage of 26 V, at a voltage gradient of 0.68 V/cm, respectively. The results showed that low-voltage constant DC immobilized fish more quickly, resulting in significant elevations of plasma cortisol levels compared to exposure of high or low doses of MS222. Electronarcosis led to an increased expression of heat shock proteins 70 ( HSP70) as well as HSP90 compared to the treatment group with MS222. Also, electronarcosis enhanced mitochondrial respiratory chain gene ( atp6, cox1 and nd5) and antioxidant enzyme gene ( CAT, SOD and GSH- px1) expression levels. In conclusion, low-voltage constant DC can disturb fish plasma biochemical profiles and gene expression levels. [ABSTRACT FROM AUTHOR]

Silver crucian carp Carassius auratus langsdorfii comprises a diploid-polyploid complex in wild Japanese populations. Bisexually reproducing diploids are sympatrically distributed with gynogenetically developing triploids and tetraploids. Triploid and tetraploid males are very rare among Japanese silver crucian carp due to their gynogenetic reproduction. We examined the genetic characteristics of progeny that arose in a tank by natural spawning of a tetraploid silver crucian carp pair. The ploidy status of 120 samples randomly collected from these progeny was determined to be tetraploid by DNA content flow cytometry. DNA fingerprints from a random amplified polymorphic DNA assay indicated that almost all the progeny examined had genotypes identical to the maternal tetraploid female with no paternally derived fragments. Selected specimens’ cytogenetic analyses revealed that the progeny examined had tetraploid chromosome numbers, categorized into 40 metacentric, 80 submetacentric, and 80 subtelocentric or telocentric chromosomes, which were arranged into quartets and six supernumerary microchromosomes. Fluorescence in situ hybridization signals were detected in four homologous chromosomes in all analyzed metaphases prepared from diploid goldfish specimens. Contrary, tetraploid silver crucian carp gave eight rDNA signals. These results suggest that gynogenetic development in eggs spawned by tetraploid females should be triggered by tetraploid males’ homospecific sperm. [ABSTRACT FROM AUTHOR]

Interferon gamma (IFNγ), a Th1-derived cytokine is one of the key molecules inducing cell-mediated immune responses in mammals. The expression of 2 distinct IFNγ ( ifng1 and ifng2) and IFNγrel ( ifngrel) genes was examined in kidney leukocytes from clonal ginbuna crucian carp Carassius auratus langsdorfii. The expression of IFNγ and IFNγrel genes was induced in kidney leukocytes by stimulation with lipopolysaccharide or phytohemagglutinin in a dose-dependent manner. The expression levels of IFNγ and IFNγrel genes in kidney leukocytes from allo-sensitized fish cocultured with allogeneic cells were higher than those from fish cocultured with isogeneic cells. The highest expression of ifng1 was observed at day 1, whereas that of ifng2 and ifngrel was detected at day 2 after cocultivation with allogeneic cells. However, the expression pattern of ifng2 and ifngrel in kidney leukocytes from allo-sensitized fish by scale-grafting was similar to those from non-sensitized fish. These results indicate that ifng1 is a major isoform of IFNγ related to antigen-specific cell-mediated immunity (CMI), and will be a useful marker to evaluate induction of CMI in ginbuna crucian carp. In addition, IFNγ would be a crucial type-II interferon compared to IFNγrel, relevant to cell-mediated immunity in fish as in mammals. [ABSTRACT FROM AUTHOR]

Seasonal habitat use by nigorobuna Carassius auratus grandoculis Temminck et Schlegel and gengoroubuna Carassius cuvieri (Temminck et Schlegel) in Lake Biwa was investigated using acoustic telemetry. Twenty-three nigorobuna and 11 gengoroubuna specimens caught using set-nets in the lake's south basin were surgically fitted with acoustic transmitters and then released. Signals from the fishes were recorded by 23 receivers installed around the lake. Between April and June 2007, the first spawning season after release, signals were received from all tagged fishes. Thereafter, until the second spawning season, signals were collected from 26 and 45% of released nigorobuna and gengoroubuna individuals, respectively. Seasonal habitat preferences for these species were studied by distance-based analysis. The analysis revealed that nigorobuna tended to stay near their spawning area in the south basin of the lake throughout the year, whilst gengoroubuna tended to show a seasonal migration pattern between the north and south basins. After the spawning season, the latter species migrated to the north basin where it remained until the next spawning season, when it returned to the south basin. This is the first report of seasonal migration of nigorobuna and gengoroubuna in Lake Biwa. [ABSTRACT FROM AUTHOR]

Funazushi (fermented Crucian Carp with rice) is a fermented fish product found only around Lake Biwa in Shiga Prefecture, Japan. It is characterized by a unique cheese-like flavor and characteristic sour taste. We analyzed the changes in the microbial community during funazushi fermentation by denaturing gradient gel electrophoresis of PCR-amplified 16S rDNA fragments (PCR-DGGE) and by plate counts. The plate counts showed that lactic acid bacteria reached 8.0 log CFU/g within 7 days of fermentation initiation before decreasing slowly to 4.0 log CFU/g during the remainder of 1-year study period. PCR-DGGE revealed that the dominant bacteria in the initial (days 14 and 30) and latter (days 90, 180, and 360) periods of fermentation were Lactobacillus plantarum and L. acetotolerans. This is the first identification of L. acetotolerans in funazushi as traditional cultivation techniques have not been sufficiently sensitive. This is the first report of PCR-DGGE being used to assess the microbial community in funazushi. This technique was also found to be effective in profiling microbial diversity. [ABSTRACT FROM AUTHOR]

Rice-fish culture, which means the simultaneous culture of rice and fish, is one of the best options to increase food production from limited land and is practiced in many countries in the world. Although many researchers and farmers believe that the rice yield is increased by fish farming in paddy fields, this hypothesis has never been fully tested. Here, we report ecological processes leading to higher rice yields in the rice-fish culture using crucian carp ( Carassius complex), which have adapted to the paddy field ecosystem in Japan. We compare the rice-fish and rice-only plots in the experimental paddy field for biota, water quality, and rice yield. Coverage of duckweed and densities of zooplankton and benthic invertebrates in the rice-fish plots were lower than those in the rice-only plots, indicating that fish utilized them as food. NO-N concentration in the rice-fish plots was higher than that in the rice-only plots, indicating that the increase in NO-N concentration results from excretion of unutilized food nutrients by the fish. Consequently, rice yield in the rice-fish plots was 20% higher than that in the rice-only plots. The fertilizing effect of the fish excrement probably increased rice yield. [ABSTRACT FROM AUTHOR]

Two cystatins (cst-I and cst-II) were purified from crucian carp eggs by acidification and subsequent ion exchange and molecular sieve chromatography. The molecular masses of cst-I and cst-II analyzed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis were 11.9 and 14.4 kDa, respectively, under reducing conditions and 13.5 and 12.7 kDa, respectively, under non-reducing conditions. The cst-I and cst-II molecules were stable after 30 min of incubation at 60 and 50°C, respectively. There was no significant loss in the inhibitory activity of either cst in the pH range 4–11. These two cystatins were able to affect the proteolysis of papain, cathepsin L, and bromelain, but they were unable to inhibit cathepsin B and trypsin. The partial N-terminal amino acid sequences of both cst inhibitors were homologous and that of cst-I was recognized as NH2-AGIPGGLVDADINDADVQ. This latter fragment shared 88.9% identity to common carp cystatin and 44.4–55.6% to cystatins of other aquatic animals. Based on these results, we conclude that the two cst inhibitors are members of family II cystatin. [ABSTRACT FROM AUTHOR]

Phosphorus (P) excreted from aquaculture systems pollutes aquatic environment. Reducing P output requires reducing P input in the feeds. Reducing P in feeds, however, increases the risk of P deficiency in fish. Thus, diagnosis of P deficiency in fish will be important to avoid chronic P deficiency. To detect incipient P deficiency, a sensitive method is needed. Previously, in trout, inorganic P transporters (NaPi) in the intestine have been shown to respond rapidly to early P deficiency. For other fishes, however, little is known about the NaPi sequences, not to mention their dietary responses. In this study, intestinal NaPi sequences were isolated anew in 23 fish species, including major aquaculture species. Also, NaPi-like sequences were isolated from three molluscan species. Phylogenetic analysis of the NaPi sequences showed reasonable agreement with known evolutionary relationships. Tissue distribution of NaPi messenger RNA (mRNA) was studied in rainbow trout, crucian carp, and tilapia by real-time reverse-transcription polymerase chain reaction (RT-PCR), which revealed distribution of NaPi mRNA in several tissues other than the intestine. Acute, but not chronic, dietary P restriction increased ( P = 0.01) NaPi mRNA abundance by twofold in crucian carp intestine. [ABSTRACT FROM AUTHOR]

Ten lots of common carp and six lots of crucian carp (each lot of 100 fish) were treated under anoxia for five days at water temperatures of 25–31°C. The average per group mortality of common carp was 17%, but none of the 600 crucian carp died. The digestive tract tissues of the common carp that died had significantly lower zinc concentrations than those that survived (59 ± 41 vs 142 ± 60 μg/[g fresh tissue], P < 0.001). The digestive tract tissues of the crucian carp had mean zinc concentrations of 652 ± 458 μg/(g fresh tissue). One lot of common carp that had low tolerance for anoxia was fed a high zinc diet (2000 mg zinc/kg diet) for 1, 2 or 6 months and then subjected to 5 days anoxia. The survival rates of those fed the high zinc diet 1 and 2 months increased from 0 to 50%, respectively; all of fish that had fed a high zinc diet for 6 months survived. Thus, anoxia survival in common carp and crucian carp is closely related to the high concentrations of zinc in their tissues. [ABSTRACT FROM AUTHOR]

The clonal triploid ginbuna crucian carp Carassius auratus langsdorfii, a naturally occurring gynogenetic fish, is a useful model for studying T-cell-mediated immunity. CD4, a T-cell receptor (TCR) coreceptor, is a membrane-bound glycoprotein found on helper T-cells, and assists in the binding of major histocompatibility complexes. In the present study, full-length cDNAs encoding the CD4 molecule from the S3n strain of ginbuna crucian carp were cloned and characterized. 5′-rapid amplification of cDNA ends (RACE) and 3′-RACE yielded two distinct cDNA clones of CD4 homolog from the ginbuna, and these sequences share 95% identity at the amino acid level. These ginbuna CD4 molecules consisted of a signal peptide, immunoglobulin superfamily (IgSf) like domains, a transmembrane domain, and a cytoplasmic domain similar to other known CD4. A tyrosine protein kinase p56lck binding motif is conserved in the cytoplasmic tail of ginbuna CD4. Phylogenetic tree analysis indicated that ginbuna CD4 sequences are closely related to CD4L-1 from other fish species. Expression of ginbuna CD4 mRNA was detected in the gill, thymus, head kidney, trunk kidney and peripheral blood leukocytes, indicating that its expression pattern is similar to that of ginbuna TCRβ mRNA. The results suggest that ginbuna CD4 sequences are useful as molecular probes for helper T-cells. [ABSTRACT FROM AUTHOR]

Lck is a member of the Src-related protein tyrosine kinase family. In mammals, it is predominantly expressed in T cells, and plays crucial role in T-cell maturation and activation. In this report, the cloning, characterization, and expression analysis of lck genes from the S3n strain of ginbuna crucian carp Carassius auratus langsdorfii is described. Three distinct lck homologs, designated as gblck-1, gblck-2, and gblck-3 were isolated from ginbuna thymus. The deduced amino acid sequences of gblck-1 and gblck-2 cDNAs exhibit conserved lck essential motif and overall structures, but gblck-3 lacks an essential region related to regulation of Src kinase activity. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis demonstrated that gblck-1 was expressed in peripheral blood leukocytes (PBLs), lymphoid organs, and mucosal tissues, as has been reported for T-cell marker genes, i.e. CD3, TCR, and lck in other fish species. In contrast, the expression of gblck-2 and gblck-3 were observed only in PBLs and lymphoid organs. In the sorted lymphocytes from kidney leukocytes using antiginbuna IgM monoclonal antibody, only sIg– lymphocytes expressed lck genes as well as the TCRβ gene. Collectively, these results suggest that lck is a useful marker for the identification of T cells. [ABSTRACT FROM AUTHOR]

Prey fish selection by Far Eastern catfish and largemouth bass were examined using bluegill, Japanese dace and crucian carp as food fish. In both aquaria (1.2 m × 0.45 m) and ponds (2.8 m × 1.2 m), bluegill was not preyed on by catfish and bass more than dace and crucian carp. In aquaria, there was no significant difference in the consumption of dace and crucian carp between catfish and bass, but in ponds, catfish preyed on dace and crucian carp more and less than bass, respectively. In the case that only bluegill and catfish were introduced in ponds, catfish consumed 4–15 g of bluegill per day. The introduction of catfish into ponds and lakes for the purpose of eradicating bluegill is considered appropriate for areas with few native fish species. [ABSTRACT FROM AUTHOR]

To investigate the emotional reactivity of fish in a novel environment, the swimway test was developed. The swimway apparatus consists of a shaded start chamber and an open, illuminated swimway. Fish were first introduced and habituated to the start chamber. A door partitioning the start chamber from the swimway was then opened, and behavioral responses of the fish in the apparatus were measured. By using the swimway test, behavioral responses to a novel environment of bluegillLepomis macrochirus, crucian carpCarassius langsdorfii, and goldfishCarassius auratuswere quantified and compared. The emotional reactivities in bluegill were found to be the lowest and crucian carp the highest, indicating bluegill are relatively active or‘bold’, and that the crucian carp are relatively passive or‘shy’, in a novel environment. It is suggested that the swimway test is applicable to examining inter-species differences in relative emotional reactivity or boldness in a simplified novel situation. [ABSTRACT FROM AUTHOR]

ABSTRACT: The thermal resistance traits of three clonal lines of the silver crucian carp Carassius langsdorfii (SCC-1, -2 and -3) were investigated. Individual juvenile fish reared at 20°C were exposed to thermal stress at 36.5 ± 0.5°C and their death times during this exposure were measured. The death times of SCC-2 and SCC-3 fish were 66.6 ± 31.2 and 144.7 ± 49.8 min, respectively. In contrast, all SCC-1 fish survived under these conditions. Furthermore, the thermal sensitivity of primary culture cells from each clone was determined at 37, 40 or 43°C by the Trypan blue assay. Under all treatment conditions, the thermal sensitivity of the SCC-1 primary cultures was lower than those of the others. These results estimated the correlation between the in vivo and in vitro thermal resistances. Therefore, the use of primary culture cells to evaluate thermal resistance could be a useful method of selection breeding. [ABSTRACT FROM AUTHOR]

The correlation between hematology and plasma chemistry was examined in natural silver crucian carp Carassius langsdorfii. Three microsatellite DNA markers identified five clonal lines. Blood was obtained from the caudal vessels and analyzed using automatic analysis systems. The correlation between several parameters including erythrocyte count (RBC), mean corpuscular hemoglobin concentration (MCHC), alkaline phosphatase (ALP), plasma glucose (Glu) and total protein (TP) was assessed by liner regression. Hemoglobin (Hgb) and hematocrit (Hct) as a function of the erythrocyte count, hematocrit as a function of the hemoglobin, mean corpuscular hemoglobin (MCH) as a function of the mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC) as a function of the mean corpuscular hemoglobin, and total protein as a function of triglyceride (TG) were positively correlated for the five clonal lines. Different regression slopes ( b -value) of RBC to Hgb and Hct were found among clonal lines, while no such differences were found among slopes of the remaining regression equation. This phenomenon suggests that the significantly different slopes among parameters, which indicated low genetic influence at the each parameter, clearly detected the genetic influences as the compound effect of these parameters. [ABSTRACT FROM AUTHOR]

Functional sex reversal of all-female nigorobuna Carassius carassius grandoculis to phenotypic males was examined by immersion exposure of fry to 17-methyltestosterone (17-MT) and controlled water temperature during early development. Fry were reared in water containing different concentrations of 17-MT at 24 and 30°C for 80 days starting 20 days after hatching. Although the fish exposed to 0.1 and 1.0 μg/L 17-MT at 24°C were all male, treatment with 10.0 μg/L 17-MT resulted in 43% females. Twenty-two percent males appeared in the control treatment at 30°C but the control at 24°C was entirely female. The proportion of males in treatments exposed to 0.01– 1.0 μg/L 17-MT at 30°C was slightly lower than in the respective treatments at 24°C. These results indicate that the phenotypic expression of sex in nigorobuna is thermolabile and that sex determination is under the control of genetic factors and temperature. Also, control of temperature during early development has been shown to be important for the production of all-female offspring for use as breeding stock for pond culture of fish suitable for preparation as ‘funazushi’. [ABSTRACT FROM AUTHOR]

Effects of the chromosome set manipulation on early embryonic development were examined in goldfish and crucian carp. Both pressure- and heat-shock treatments of fertilized eggs induced developmental disorders such as thin blastodisc formation, delay of epiboly, and deficiency of dorso-anterior structures. The longer the treatments were applied to the eggs, the more frequently severe dorsal deficiencies were induced in the embryos. No and reduced signals of goosecoid mRNA, a dorsal mesodermal marker, were observed in embryos treated with heat-shock at 40°C for 1 min at 5 min postfertilization. These results suggested that such treatments should affect not only the retention of the second polar body, but also the suppression of dorso-ventral differentiation. [ABSTRACT FROM AUTHOR]

Focuses on the purification and characterization of myofibril-bound serine protease from crucian carp Carassius giberio langsdorfi muscle. Effect of various protease inhibitors on the activity of the purified myofibril-bound serine protease; Degradation of myofibrillar proteins by crucian carp myofibril-bound serine protease; Participation of endogeneous serine protease on the initial degradation process of myofibrillar proteins.