Abstract:Fish are an ideal model for research on functional genes. Transgenic fish have many important applications in aquaculture. Recently, a number of researchers have evaluated the use of transgenic fish to improve the commercial value of a species by manipulating traits such as growth, sex, and disease resistance. In particular, the function of sex-determining genes has received significant attention. The current studies of gene function, which are related to sex differentiation, are largely confined to a few fresh water fish species. In contrast, little effort has been made to study gene function in marine fish because of logistical difficulties, such as the presence of a hard fertilized egg membrane, low survival rate, and/or long period of a generation. To address this gap, we studied the function of a homologous gene in a model marine fish species. A number of methods have been used to modify the fish genome, among which microinjection is the most commonly used approach. We constructed expression vectors by subcloning Cinto a pIRES- hrGFP-1α vector. in Medaka was induced by injecting these GFP constructs into the cytoplasm of fertilized Medaka embryos at the one cell stage. We then measured GFP expression and hatching rate. Additionally, we quantified the level of gene integration, expression, and the effect on expression. GFP was expressed at high levels 48 h after injection and the number of embryos expressing GFP decreased with the development of embryos. The hatching rate and integration efficiency of embryos injected with the homologous expression vector was significantly higher than those injected with the heterologous . Furthermore, in fishes with was down-regulated. Our research provides a foundation for the study of sex differentiation and contributes to our knowledge of sex-determining genes in marine fish.

Abstract:TLR9, a member of the Toll-like receptor family, plays a key role in the innate immune system by identifying the DNA CpG motif of bacteria and viruses. Using rapid amplification of cDNA ends (RACE), we cloned the full length L., Abbr. Ca). We then evaluated the effects of exogenous hCG and gonad development on CacDNA was 3 509 bp in length with a 3′-untranslated region (242 bp), a 5′-untranslated region (72 bp), and a 3 195 bp open reading frame (ORF). The ORF of CacDNA encodes a 1 064 amino acid protein with a signal peptide of 19 amino acids, 15 leucine rich repeat (LRR) motifs, one transmembrane zone, and one Toll/IL-1 receptor (TIR) domain. The amino acid sequence of CaTLR9 possessed 92%, 83% and 79% identity with the TLR9s of , respectively. The expression level of was highest in the spleen of crucian carp, followed by the kidney and gill. The level of expression was low in the remaining tissues. The expression of was higher during the breeding season than the non-breeding season. Additionally, injections of exogenous hCG significantly up-regulated the expression of TLR9 is a new candidate target gene for investigating non-specific immunity in crucian carp and improving the health of cultured fish.

Abstract:

Abstract:-δ subunit). The full-length cDNA of this gene was cloned by rapid amplification of cDNA ends (RACE) PCR, and the expression of this gene was detected in different tissues by semi-quantitative RT-PCR. We then measured the relative expression of this gene in the different tissues following exposure to acute hypoxia stress of mg/L, 3.37 , or 0.54 mg/L dissolved oxygen [DO] using quantitative real-time PCR. The full-length cDNA of the mitochondrial ATPase subunit gene was 762 bp, containing an open frame reading of 480 bp encoding 159 amino acids, and a 114 bp 5-untranslated region. The deduced amino acid sequence of the mitochondrial ATPase (89%) and moderate similarity with Oncorhynchus masou formosanus(74%), and (69%). Expression of the gene was highest in the heart followed by the muscle, with low levels of expression in the brain, liver, and spleen in silver carp. Expression of this gene decreased gradually as dissolved oxygen levels decreased. Expression in the heart was significantly lower (0.05) in the hypoxia-exposed fish than in the control group. Conversely, levels were initially significantly higher (<0.05) in the brain, liver, spleen, and muscle of hypoxia-exposed fish, before decreasing significantly (<0.05). -ATPase activity first increased then decreased in all the tissues during acute hypoxia stress. Changes in expression of the were consistent with changes in ATP enzyme activity in the brain, liver, spleen, and muscle, but not in the heart. The initial increase in expression of changes in desolved oxygen(DO). However, if damage to the inner mitochondrial membrane leads to loss of self-regulation when DO becomes too low, expression will rapidly decrease. This disrupts energy metabolism and blocks energy synthesis. Oursubunitgene may play a role in the response to hypoxia stress and influence the production and activity of ATPase in silver carp.

Abstract:Cyclins are the positive regulatory subunits of cyclin-dependent kinases (CDK). They play a critical role in the coordination of the eucaryotic cell cycle by binding to the catalytic subunits of CDKs. They share distant sequence homology over a 100 amino acid region called the cyclin box and have been classified into two phylogenetically divergent subfamilies. The first contains A, B, D, E, F, and G cyclins and the second contains the C and H cyclins. Shrimp culture is limited by a lack of methods to breed adults in captivity. This is because female shrimp are unable to reach ovarian maturity without intervention using destructive, expensive, or time consuming methods such as eyestalk-ablation. Thus, there is a need to better understand the of ovarian development. Cyclin E is a cell cycle regulatory factor that plays a very important role in cell proliferation. To better understand the potential function of cell cyclin E in regulating shrimp reproduction, the full-length cDNA sequence of cell cyclin E from black tiger shrimps (denoted as Pmcyclin E) was obtained by high throughput transcriptome sequencing and RACE. The cDNA of Pmcyclin E was 1 706 bp, including a 132 bp 5′-terminal un-translated region (cUTR), a 311 bp 3′ UTR with a poly (A) tail, and an open reading frame (ORF) of 1 263 bp encoding a polypeptide of 420 amino acids with a predicted molecular weight of 47.9 kD and predicted pI of 5.85. The results of Blast and phylogenetic analyses suggest that Pmcyclin E is a new member of the shrimp cell cyclin E family. We measured mRNA expression of Pmcyclin E in nine tissues by real-time PCR. Expression was highest in the ovary and eyestalk, moderate in the intestine, brain, and muscle, and very low in the stomach and . Pmcyclin E expression in the ovary was significantly reduced by injection of MIH, and was induced after eyestalk ablation, suggesting that the gene plays an important role in Our results provide insight into the function of Pmcyclin E in the regulation of ovarian development in the black tiger shrimp.

Abstract:) are a family of ubiquitous proteins that minimize the harmful effects of oxidative stress by catalyzing the reduction of hydrogen peroxide (H₂O₂) and organic hydroperoxides to less harmful forms. A full-length cDNA corresponding to a 2-Cys Macrobrachium nipponense and designated as (GenBank accession no. KC866353). The full-length cDNA was 998 bp, containing a 72 bp 5′ untranslated region (UTR), a 212 bp 3′UTR with a poly (A) tail, and a 594 bp open reading frame (ORF) encoding a polypeptide of 198 amino acids with a molecular mass of protein possesses two conserved cysteine residues that play an essential role in the antioxidant activity of this proteins. The protein, as deduced from the cDNA sequence, has a high level (87%) of sequence similarity to the 2-Cys gene was expressed in the ovary, hepatopancreas, muscle, heart, testis, and intestines, with expression being highest in the hepatopancreas. mRNA expression was significantly higher in the hepatopancreas and gill of prawns exposed to hypoxia (12 and 24 h) and reoxygenation (6 h) stress than in the control group. This suggests a possible role in alleviatingoxidative stress by increasing mRNA expression in response to environmental hypoxia and reoxygenation.

Abstract:), a flatfish of deep water species, is a high-nutrition and economic valued species and currently cultured widely in ChinaIn recent years, however, serious germ plasm degeneration occurred due to the lack of long-term and effective broodstock management programsproduction of farmed turbot became highly unstable and total output declined gradually. Thereforethe genetic improvement of turbot will be necessary to sustain the industry development. Within a breeding program in aquacultureThe traits which determines the total harvest yield are highly desirable economic traits, for example, fast-growing, high survival, . The sustainability of turbot culture has been threatened by disease outbreaks and, at present, there is no program in place to minimize such outbreaks. To aid selective breeding for disease resistance traits, in this, study, we conducted a challenge test against using 30 2nd-generation families that were constructed by consecutive selection for faster growth from a base population. We quantified their disease resistance based on survival and tested for differences among families using an odds ratio. There was a significant difference in disease resistance to bacterial infection among families. Twelve families (Family 1, 3, 4, 6, 9, 12, 14, 19, 22, 23, 29, and 30) had high disease resistance with a >65% survival rate; 11 families (Family 8, 10, 13, 16, 18, 20, 21, 24, 25, 27, and 28) had moderately high disease resistance with a 50%–65% survival rate; 3 families (Family 2, 7, and 17) had moderate disease resistance with a 35%–50% survival rate; and 4 families (Family 5, 11, 15, and 26) had low disease resistance with a <35% survival rate. We calculated the odds ratio for disease resistance by b-COX regression analysis, and screened 5 superior families (Family 3, 9, 14, 19, and 23) for third parental generation breeding. The selected families can be used as the core breeding population for turbot resistance to. In addition, the results of the study also provide a reference for selective breeding for disease resistance in cultured turbot.

Abstract:Color polymorphism is relatively common in marine shellfish. Shell color affects the visual perception of products which, in turn, influences consumer preference and product value. The shell color of marine mollusks is a genetically-based phenotypic trait and is therefore amenable to artificial selection. Furthermore, distinctive pigment colors or color patterns in several marine shellfish species are controlled by genes segregated at only one or two loci. The genetic control of shell pigment was recently determined for , and the narrow-sense heritability of left-shell pigmentation was estimated at 0.59 ± 0.19. To increase the value of sold as “singles” for the half-shell market, there has been a recent increase in interest in selective breeding for desirable shell colors in . In particular, research has focused on the relationship between shell color and phenotypic traits in and the effect of genotype-environment interactions on adult fitness. Four shell color families (white, black, golden, and purple) and the control group were established by separately selecting corresponding parents in Rushan Bay, . The larvae, spat, and adults were reared following standard practices, and the rearing conditions were identical between families to minimize environmental effects. We measured the growth performance (shell height, shell length and total weight) and survival rate of these families during the larval, spat, and adult periods. We used bi-independent variables analysis to test the genotype-environment interaction effect of the phenotypic traits during the adult period. At days 10, 15, and 20, the larval shell height of the golden and purple shell families was significantly higher than that of the white shell family and the control family. At days 15 and 20, the larval survival rate of the purple shell family was significantly higher than that of other families (<0.05). At days 40 and 100, the . At day 160, the juvenile shell height of the white shell family was lower than that of the other families at both study locations . There was no sjuvenile period . At day 340, the shell height and total weight of the golden shell family were significantly higher than those of the white shell day 420, the adult shell height and total weight of the golden and purple shell families were significantly higher than those of the white shell, the black shell, and the control families (<0.05). The survival of the purple shell family was higher than that of the other families (<0.05). The shell height and shell length of adult oysters were affected by the interaction of genotype and environment. Our results suggest there is an association between shell color and other phenotypic traits in . The interaction between genotype and environment had a scaling influence, so should have little effect on breeding programs for . Our results provide a basis for the selective breeding of high yield using shell colors as a candidate marker.

Abstract:Epinephelus coioides (♀)×)] during the larval and juvenile stages. We measured the total length, pre-anal length, trunk height, head length, eye diameter, mouth width, the second dorsal fin spine, pelvic fin spine, pectoral fin, anal fin, and tail fin of Qinglong grouper (from hatch to 28 d) and captured images of each individual using Q-Capture Pro 6. The average total length of newly hatched larvae was (1.62±0.26) mm. After 28 d, the total length of juveniles was (16.58±1.09) mm at a water temperature of (30±1) and a salinity of 28±1. The growth in total length of Qinglong grouper was divided into three stages. The growth rate during the first, second, and third stages was 0.11 mm/d (from hatch to 7 d), 0.37 mm/d (from 8 to 21 d), and 1.51 mm/d(22 d afterwards), respectively. There was a significant difference in the growth rate between larval and juvenile stages (<0.05). Some of the organs exhibited allometric growth in early ontogeny. Head length and trunk height were positively allometric up to the inflexion point, then switched to isometric and negatively allometric, respectively. Pre-anal length was characterized by isometric growth and had no inflexion point during the larval and juvenile stages. The growth in the head (inflexion point at 21–22 d) and sensory organs (inflexion point at 20–21 d) was positive up to the inflexion point, then became negatively allometric, respectively. The second dorsal fin spine and pelvic fin spine exhibited strong positive allometry at first, before becoming negatively allometric. The inflexion point of the second dorsal fin spine was between 20 and 21 d, whereas that of the pelvic fin spine was at 17 d. The second dorsal fin spine and pelvic fin spine reached a maximum at 24 d. From hatch to day 26, pectoral and tail fin growth was positively allometric, and their inflexion points were between 14 and 15 d, and 22 and 23 d, respectively. Anal fin growth was positively allometric and had no inflexion point. This pattern of growth results in rapid improvement in swimming ability, thereby allowing individuals to search for food and escape predators. Our results suggest that the organs involved in feeding, sensing, and swimming developed most rapidly during the early developmental stages in Qinglong grouper. To increase the survival rate of Qinglong grouper during early life stages, it is critical to provide environmental conditions that account for the priority order of organ development.

Abstract:Traditionally, fish oil is the main lipid source in the feed for most species in aquaculture owing to its effective supply of energy and high content of essential fatty acid. The fatty acid especially n-3 HUFA from the fish oil had also been proved to have positive effect on maintaining the immune system. However, the decline of fish oil production from wild fisheries has resulted in a supply shortage and price escalation of fish oil. Therefore, it has been a major challenge to find viable sources of oil to substitute fish oil. Among available vegetable oils, soybean oil has been widely chosen due to its availability, price and abundant content of fatty acid. In this study, we evaluated the effects of diets with different fish oil and soybean oil ratios on grouth, non-specific immune response and disease resistance in Chinese mitten crab (). Five isonitrogenous and isoenergetic diets were formulated in which 0% (control: F1), 25%, 50%, 75%, or 100% (F2−F5) of the fish oil was replaced with soybean oil. Juvenile crabs (mean weight 0.27±0.03 g) were assigned to one of five treatment groups (four replicates per group) and fed one of the diets for 42 d. There was no significant difference in the survival rate among the treatments (0.05). The weight gain was significantly higher in the F4 group than in the F1 group (0.05). Similarly, the crabs in the F4 group had significantly higher serum ACP (acid phosphatase), AKP (alkaline phosphatase), and serum SOD (superoxide dismutase) activities than the other treatment groups (0.05). F4 and F3 group were significantly higher than the other groups (0.05). Serum MDA (malondialdehyde) content was significantly higher in the F1 group than in the other groups, but there was no difference between the other groups (0.05). Serum PO (phenoloxidase) activity was higher in F4 and lower in F5 than the other groups (0.05). There was no difference in serum lysozyme activity among the groups (d. The first death was recorded in F5, and the crabs in F5 had significantly higher cumulative mortality than those in F1 and F4 (0.05), but there was no significant difference among the other groups (0.05). In conclusion, complete substitution of fish oil with soybean oil did not affect growth performance, but did reduce the ability to resist disease. Our results suggest that replacement of 75% fish oil with soybean oil in the diet of Chinese mitten crab can improve growth with little effect on disease resistance.

Abstract:Because of a decrease in production and increase in the cost of fishmeal, there is increased interest in the use of plant-based feed in aquaculture. However, one of the major problems associated with the use of plant protein in fish feed is the presence of anti-nutritional factors, such as phytate, which is the primary storage form of phosphorus. Phytate is essentially unavailable to monogastric or agastric aquatic animals as they lack intestinal phytase that promote phytate hydrolysis during digestion. To address this issue, diets for monogastric or stomachless animals are often supplemented with monocalcium phosphate (MCP) to meet their phosphorus requirements. However, MCP is derived from fossils so it is a non-renewable resource. Furthermore, the cost of rock phosphorus has increased dramatically over the past several years. Alternatively, exogenous phytase can be added to hydrolyze phytate, and thus improve the use of phytate phosphorus. Thus, the addition of phytase may lower the need for MCP supplementation, thereby lower feed costs. This strategy may also lower the concentration of phosphorus excreted, resulting in lower eutrophication of the surrounding waters. We evaluated whether neutral phytase could partially replace MCP, and thus reduce the dietary inclusion of MCP. The fish (initial body weight: 11.52 ± 0.12 g) were fed one of four diets for 8 weeks: a control diet (designated P1.5) was prepared with 1.5% MCP but without phytase and three other diets (designated as PP1.5, PP1.0, and PP0.5) were supplemented with 1.5%, 1.0%, or 0.5% MCP, respectively, and 200 mg/kg (diet) phytase. Fish fed PP1.0 and PP0.5 had no significant change in weight gain rate(WGR), specific growth rate (SGR), protein efficiency rate (PER), or feed conversion ratio (FCR) compared with the control (>0.05), whereas fish fed PP0 had significantly lower growth performance in the above parameters (>0.05). Phytase addition did not affect body composition. The apparent digestibility coefficients (ADCs) of crude protein and phosphorus increased when fish were fed . Additionally, phosphorus discharge was significantly reduced in fish fed diets in which MCP was replaced by phytase. Our results suggest that the dietary phosphorus requirement for meeting normal growth in black sea bream is0.51%. MCP can partially be replaced by phytase without affecting the growth of black sea bream. A diet containing 200 mg/kg phytase is equivalent to 1% MCP. The partial substitution of MCP by phytase not only reduces inorganic phosphorus addition to the surrounding waters, but also improves use of phosphorus in the feed.

Abstract:Our objective was to evaluate the effects of fish meal (FM) replacement with defatted silkworm pupae (DSP) on the intestinal bacterial community structure in Jian carp () using culture-independent 16S rDNA PCR-DGGE fingerprinting. Five isonitrogenous (36.8% crude protein) and isoenergetic (5.5% crude lipid) diets were formulated as follows: one basal diet with 10% FM (DSP0), three diets with 25%, 50%, and 75% FM replacement (DSP25, DSP50, DSP75), and two FM replacement diets (DSP50 and DSP 75) that were supplemented with 0.7% crystalline lysine (DSP50-Lys, DSP75-Lys). A total of 324 juvenile Jian carp (mean body weight: 15.30±2.97 g) were randomly assigned to one of 6 groups (3 replicates per group, 18 fish per replicate). A PCR-DGGE fingerprint analysis revealed that DSP0, DSP25, DSP50, DSP50-Lys, DSP75, DSP75-Lys had bands, respectively. The dominant bacteria were represented by 1The similarity coefficient between the DGGE fingerprint of DSP0 bacteria and the other groups was 50.7%, 50.6%, 69.0%, 42.4%, and 66.7%, respectively. The major bands were recovered, cloned, and sequenced, yielding 19 sequences.The sequences were analyzed by comparison with the NCBI database. The bacterial community consisted primarily of Actinbacteria, Gammaproteobacterial, Cyanobacteria, Bacteroidetes, and Fusobacterial, and included 15 sequences that were uncultured. In conclusion, replacement of graded dietary fish meal protein with defatted silkworm pupae meal had a the intestinal bacterial community structure in Jian carp. However, the addition of lysine reduced this effect. Our results provide a foundation for further development of alternative carp feeds.

Abstract:-propiothetin (DMPT) on growth, proximate muscle composition, and protein metabolism in =1 800, average initial body weight: 4.20±0.02 g) were cultured in a flow through system. The fish were randomly divided into six triplicate groups of 100 fish and fed diets containing different levels of DMPT (0, 0.25%, 0.5%, 0.75%, and 1.0%) for 56 d. Weight gain rate was highest at 0.2% DMPT supplementation (<0.05). The optimum supplementation was 0.24% based on a polynomial regression analysis between dietary DMPT level and weight gain rate. Serum total protein, albumin, and globulin increased significantly with 0.05% DMPT supplementation (<0.05) and serum total protein, globulin and serum aspartate aminotransferase increased significantly with 0.2% DMPT supplementation (<0.05). Meanwhile, liver and muscle protein levels and protease activity in the digestive track increased significantly as dietary DMPT supplementation increased between 0.02% and 0.5% (<0.05). The liver somatic index increased significantly with 0.05% DMPT supplementation. DMPT supplementation had no effect on muscle crude lipid, ash, amino acid profile, or serum alanine transaminase (0.05). Our results suggest that growth performance and protein levels were improved by dietary DMPT supplementation in taimen and 0.02%–0.5% DMPT supplementation can increase the protein storage in muscle and liver.

Abstract:free essential amino acids, hematological characteristics, and the immune response in juvenile . Six isonitrogenous and isoenergetic semi-purified diets were formulated to contain graded dietary arginine levels (actual levels: 0.83%, 1.30%, 1.81%, 2.35%, 2.82%, and 3.36%). The protein source consisted of casein-gelatin-fish meal and a crystalline amino acid mixture. The experimental fish (2.6±0.1 g) were randomly assigned among 18 cages (1 m×1 m×1 m, 30 ind/cage). Each experimental diet was fed to fish in triplicate tanks using a completely randomized design. Weight gain rate (WGR) and feed efficiency rate (FER) increased significantly with an initial increase in dietary arginine levels (<0.05), but tended to plateau above a dietary arginine level of 1.81%. The crystalline arginine was used by juvenile , but there was a negative correlation between arginine and lysine content in the plasma. Dietary supplementation with arginine caused a significant increase in urea, total protein (TP) and globulin (GLB) concentrations ( (AST) activity, and an invariable level difference in the plasma glucose (GLU) concentration, alanine aminotransferase (ALT) activity and albumin (ALB) in juvenile relative to the control diet (0.85%). Hemoglobin content (HGB) content, red blood cell (RBC) count, and white blood cell (WBC) count increased significantly (<0.05) with an increase in dietary arginine level between 0.83% and 1.81%. However, there was a significant (<0.05) decrease with an increase in dietary arginine levels between 2.35% and 3.36%. The maximum RBC count, WBC count, and HGB content were observed in animals fed 1.81% dietary arginine. Dietary arginine level significant affected the respiratory burst assay of blood cell (<0.05), and had a negative effect on cumulative mortality in juvenile . Our results suggests that feed supplementation with 1.81% and 2.35% arginine enhances amino acid absorption and stimulates immunity and resistance to pathogenic infection in juvenile

Abstract:is a fast growing, easily domesticated, carnivorous fish that is valued for its taste and nutritional value. This specieshas been domesticated and bred successfully in more than a dozen provinces in China, including Heilongjiang, Liaoning, Shandong, and Xinjiang. Despite prior research, the nutrient requirements of are poorly understood. We evaluated the effects of -inositol (MI) levels on body composition, growth performance, and digestive enzyme activity . We formulated seven semipurified basal diets using fish meal, gelatin, and casein as the protein source. The MI content of the diets was 99.8, 199.8, 299.8, 499.8, 799.8, 899.8, or 5 099.8 mg MI/kg diet. Each diet was fed to triplicate groups of 30 fish (mean initial weight: 2.83±0.44 g) for 56 d. The weight gain rate was highest in<0.05) than that in fish fed diets with 299.8 mg MI/kg. Weight gain rate was lowest in the group fed a diet with 99.8 mg MI/kg. Feed conversion ratio was lowest in <0.05) lower than in fed a diet with 299.8 mg MI/kg or 5 099.8 mg MI/kg. The feed conversion ratio was highest in fish fed a diet with 5 099.8 mg MI/kg. The sgrowth rate was significantly higher 499.8–899.8 mg MI/kg than fish fed diets with -inositol did not affect moisture, crude lipid, crude protein, or amylase activity in the liver and lipase activity in fed a diet with 499.8 mg MI/kg had the highest (<0.05) protease activity in the liver, followed those fed by 699.8 mg MI/kg. Lipase activity increased initially and then decreased as the level of dietary MI increased. Lipase activity in the liver of <0.05) higher than in those fed 99.8 mg MI/kg. Protease activity was significantly higher (<0.05) in the intestine of fed diets with 199.8–499.8 mg MI/kg than those fed the other diets. Lipase activity was significantly higher in the intestine of fed 299.8–899.8 mg MI/kg than fish fed 99.8 mg MI/kg. Amylase was significantly higher (<0.05) in the intestine of fed 499.8 mg MI/kg than in the remaining groups. In conclusion, supplementation of diets with moderate concentrations of -inositol resulted in better growth performance and digestive enzyme activity in . Feeding diets with lower MI concentrations was associated with lower weight gain, growth rate, crude lipid levels, and digestive enzyme activity. Feeding diets with excessive MI was associated with reduced growth performance, digestive enzyme activity and feed conversion efficiency. the weight gain rate in was maximized by feeding 536.6 mg MI/kg diet. Our results provide insight into the dietary MI requirements for .

Abstract:spawning stocks in the northern Yellow Sea between 1986 and 2010. The range and mean values of the four basic biological indicators (fork length, weight, net weight, and gonad weight) were significantly higher in 1986 than in 2010. In 1986, the age structure ranged from age 1⁺ to 7⁺ and was dominated by age 2⁺−3⁺ individuals. In 2010, the age range was reduced (1⁺−3⁺) and the dominant age was 2⁺. In 1986, the range in GSI was 3.43−21.87 (mean 11.63) and the mean GSI varied significantly among fish of different lengths. In 2010, the GSI ranged between 8.33 and 20.50 (mean 13.16) and there was little difference in mean GSI among different length groups. In both years, the gonads of female fish were primarily at stages and the GSI increased with increase in gonad maturity before spawning. The mean GSI increased between 1986 and 2010 for the same sized fish. The absolute fecundity ( grains (mean: 50.2502×10⁴±1.2615×10⁴) and the most common value was between 40×10⁴ and 70×10⁴ grains in 1986. In 2010, the range was 23.4520×10⁴−62.0805×10⁴ grains (mean: 40.7312×10⁴±2.1458×10⁴ grains) and the most common group was 30×10⁴−50×10⁴ grains. In 1986, the relative fecundity (r/L) was in the range of 269−2 519 grains/mm (mean: 1 467±33 grains/mm) with most fish being in the range 100−1 600 grains/mm). The relative fecundity was in the range 303−1 552 grains (mean: 1 041±21 grains/g) with most fish being in the range 900−1 300 grains/g). In 2010, the relative fecundity (r/L) was in the range of 798−1 864 grains/mm (mean: 1 279±36 grains/mm) with most fish being in the range 900−1 300 grains/mm). The relative fecundity was in the range 705−1 724 grains/g (mean: 1 170±31 grains/g) with most fish being in the range 1000–1 300 grains/g). Compared with 1986, the relative fecundity increased by 11.93% in 2010, while the absolute fecundity decreased by 18.45% within the same fork length range. These changes in the reproductive characteristics may be caused by simplification of the age structure, individual miniaturization, or growth acceleration in Scomber japonicus resources, we suggest the fishery administrative department should consider additional protective measures at the primary spawning ground and during the spawning period to limit the over harvest of spawning stocks in the East China Sea and Yellow Sea.

Abstract:(Bleeker), is a freshwater fish that is endemic to China, and the only representative of the Catostomidae in Asia. Historically, were primarily distributed in the Yangtze and Minjiang (Fujian Province) rivers. Currently, the only remaining wild population is in the Yangtze River, primarily in the middle and upper reaches. The species was listed as a class state protected species by the Chinese government in 1988 and as a vulnerable species (VU) by the International Union for Conservation of Nature in 1998. Currently, hatchery-reared juvenile are released into natural river systems to supplement the wild population in the Yangtze River. However, the effectiveness of these enhancement efforts has not be evaluated to date. To address this, we collected 149 breeding parents and 65 recaptured individuals, and evaluated the parentage relationship using 11 polymorphic microsatellite loci. A total of 140 alleles were obtained and the mean observed and expected heterozygosity was 0.771 and 0.759, respectively. The range of the non-exclusion probability was 0.356–0.890 and the combined non-exclusion probability (first parent) of 11 loci was 99.998 3%. Eleven of the 65 recaptured individuals were offspring of the breeding parents (4 from 26 samples in 2011, 3 from 16 samples in 2012, 4 from 23 samples in 2013). Our results suggest that the total contribution of the enhancement to the wild population of was 16.92% in the middle and upper reaches of Yangtze River.

Abstract:from the Southwestern Atlantic Ocean in 2011. The sagittae of were classified into six types based on differences in the Otolith Posterior, Excisural Notch, Antirostrum, and Radiate Stripes. There was a significant difference (up to 36.4%) in the coefficients between two of the six types (<0.05: one-way ANOVA based on 77 coefficients derived from the elliptical Fourier). Our analysis combining quantitative and qualitative approaches indicated that: (1) it is feasible to classify the sagittae types based on morphological characters; (2) it is more accurate to describe the diversity of sagittae types and morphological characters using a combination of quantitative and qualitative approaches; (3)the elliptical Fourier analysis distinctly reflected the differences among the six sagittae types. The percentage of different sagittae types changed with the fish length and sagittae length, and there were about 20.2% fishes whose left sagittae and right sagittae were belong to different types. Type P. ramsayigradually changed into a fusiform shape There were always many sagittae types no matter in which body length groups, suggesting that the diversity of sagittae morphology is retained at every developmental stage of comprehensive evaluation of the variety of types and take into account the differences between the left and right sagittae.

Abstract:Todarodes pacificus using data collected from bottom trawl surveys in the East China Sea during the summers between 2009 and 2012. We estimated the resource density, sex ratio, size structure, and the relationship between mantle length and body weight and mantle length at first maturity in each year. individuals were common but unevenly distributed. The population density was highest in 2009 and lowest in 2010. There was no difference (>0.05) in the abundance of males and females, with the total sex ratio being 1T. pacificus consisted primarily of immature individuals and the dominant mantle length was less than 200 mm. The dominant mantle length was highest in 2012 and lowest in 2011. The relationship between mantle length and body weight was quantified as an exponential growth curve, and there were significant differences among years (<0.05). The stage of maturity increased with mantle length increasing. The mantle length at first maturity in females was larger than in males. In summary, the population of during the summer fishing season consisted primarily of immature individuals from the autumn and winter spawning groups, with a low number of small mature individuals from the summer spawning group. We observed intra annual differences in the rate of growth and development and the population structure. Our results provide a theoretical basis for managing the fishery in the East China Sea during the summer fishing season.

Abstract:Yellow River estuary is located at the intersection between Bohai Bay and Laizhou Bay, and is an important spawning, feeding, and rearing ground for marine organisms because of the abundant food supply. s (WSDR) were implemented in 2002 and the period between June 16, 2012 and July 9, 2012 was the 14^th time the regulations had been invoked. However, it is unclear whether the WSDR affects fish community structure and distribution. We used survey data collected before, during, and after were implemented in the Yellow River estuary in 2012 to compare the fish community structure and determine the ecological impact of the WSDR. Fifteen sample sites were established between 3735′E. We calculated the index of relative importance (IRI), the Margalef richness index (′), and the Pielou’s evenness index (′) as measures of fish community structure. A total number of 39 species were captured during the three surveys, belonging to 8 orders, 23 families, and 37 genera, of which 27, 33, and 30 species were captured before, during, and after implementation of the WSDR, respectively. The dominant order was Perciformes. The assemblage was dominated by demersal fishes (percent of biomass = 95.7%) before implementation of the WSDR and the dominant species was . Conversely, the community was dominated by pelagic fishes during and after the WSDR were implemented (percent of biomass = 72% and 67.1%, respectively). The dominant species were Sardinella zunasi, and . The community was dominated by warm water species in all three surveys. The average relative biomass was (6.4±1.9) kg/h and there was little difference in biomass between sites prior to implementation of the WSDR. During implementation of the WSDR, the biomass was (62.1±29.1) kg/h and fish were primarily distributed offshore, particularly in the northwest of the estuary. After implementation of the WSDR, the biomass was (48.2±17.2) kg/h and fish primarily distributed in the estuary and the southeast of survy area. The Margalef richness index () was 1.24±0.10, 1.27±0.08, and 1.35±0.08 for the three surveys ′) was 0.63±0.04, 0.36±0.04, and 0.50±0.04 and Pielou’s evenness index (and ′ were highest before the WSDR was implemented and lowest during implementation of the WSDR, and were significantly different (<0.01) among the three surveys. We conclude that sediment deposition altered the distribution of demersal fishes in the Yellow River estuary. However, the addition of large volumes of fresh water and nutrients into the Yellow River estuary had a positive effect on pelagic fishes, especially those that preyed on plankton. To more accurately determine the influence of WSDR on fish community structure, future analyses should account for environmental changes during implementation of the WSDR in the Yellow River estuary.

Abstract:is an important pathogenic bacterium of most marine aquaculture animals that has caused significant losses within the aquaculture industry. The pathogenicity of is influenced by quorum sensing, meaning that population density plays a role in determining the outcome of an infection. Thus, there is a need to develop a method to detect the density of V. harveyi species-specificP2 gene to establish a SYBR Green I real-time fluorescence quantitative PCR detection method. A 151 bp gene fragment was amplified from the chromosomal DNA of from different sources. The primers did not cross react with nine other bacteria species using conventional PCR, suggesting the primer pair has good intra-species specificity and inter-species commonality. A recombinant plasmid containing the was constructed and used to construct the standard curve. The standard curve for the +37.48. The correlation coefficient was 0.998 and the amplification efficiency was 1.00, indicating that there was a good linear relationship between initial templates and values. The melting curve had only one specific peak at an annealing temperature of 60. The detection limit of the assay was seven copies per reaction, which is 10 000 times more sensitive than that of conventional polymerase chain reaction (PCR). The results of intra- and inter-assay variability tests demonstrated that the method was highly reproducible. Our results suggest that this SYBR Green I real-time PCR assay may be used for the rapid and accurate detection of from infected aquaculture species. This will allow early diagnosis of infection and improve the efficacy of disease prevention and surveillance programs.

Abstract:cells (F-AH) were used as an antigen to immunize healthy) via intraperitoneal injection. Peripheral blood samples were collected from immunized and control iant salamanders at 1, 4, 7, 21 and 28 d post-immunization immuneresponses by counting and classifying blood cells, determining the phagocytic percentage and index and serum agglutinating antibody titers. Compared to the control group, the number of erythrocytes and leucocytes in the peripheral blood of immunized animals increased significantly at 4, 7 d post-immunization, and reached a maximum value of 7.83×10⁷/mL and 6.74×10⁶/mL The percentage of neutrophils reached a maximum value of % at 4 d post-immunization and the number of monocytes reached a maximum value of % at 7 d post-immunization. The phagocytic percentage and phagocytic index increased significantly.at 4 d post-immunization, respectively. The number of lymphocyte and the serum agglutinating antibody titers increased significantly, and peaked at resulted in a relative percent survival in the immunized group of 69%. The results from this study demonst rated that F-AH enhanced the immunity of the iant salamander by increasing the number of erythrocytes and leucocytes in peripheral blood, improving the activity of phagocytes, the serum agglutinating antibodytiter and providing

Abstract:(AHPNS) or Early Mortality Syndrome (EMS), first reported officially in China in 2010, has caused large-scale die-offs of cultivated shrimp in several countries in Asia. The causative agent of the disease is , a strain of a bacterium commonly found in brackish coastal waters around the globe. To reduce the impact of the disease, it is important to understand how environmental factors, such as nitrite nitrogen levels, affect the pathogenicity of . We evaluated the effect of environmental nitrite levels on immune-related enzymes (glutamic-pyruvic transaminase, ALT; glutamic oxalacetic transaminase, AST; alkaline phosphates, ALP; lysozyme, LSZ) in , 6nitrite for 20 d. The shrimp in the treatment and control groups were then challenged by . The moribund shrimp were anorectic and the hepatopancreas of deceased shrimp was pale to white and atrophied. The cumulative mortality peaked 48 h after exposure to and was 0, 4%, 8%, 16%, and 24% under exposure of 0.0, 2, 6, 10.0 mg/L nitrite, respectively. ALT activity increased initially in the control, 2 mg/L groups then decreased, whereas activity continued to increase in the 6 mg/L groups. The activity of AST in the control and 2groups increased and then decreased, whereas levels continued to increase in the 4and 10 mg/L groups, the activity of ALP increased initially before returning to normal levels, whereas levels continued to decrease in the 6 mg/L groups. LSZ activity was significantly higher in the control than in the 6 mg/L groups. Our results suggest that exposure to high nitrite nitrogen concentrations can inhibit the immune response of , resulting in an increase in mortality. Thus, it is important to regulate the concentration of nitrite nitrogen in the aquatic environment to prevent the break out of AHPNS.

Abstract:with seven transmembrane alpha-helixs, G-protein-coupled receptor and of great importance in chordate physiological function. The melanocortin receptor family has five subtypes (MC1R, MC2R, MC3R, MC4R and MC5R) in mammalian and tetrapod, with rather diverse functions. It has been confirmed that MCRs are involved in diverse number of physiological functions, including pigmentation, steroidogenesis, energy homeostasis, inflammation and sexual function. In recent years, fish MCRs have gained more and more concern of researchers. Different MCR subtypes have been cloned and analyzed in several fish species. The MCRs of fish, the earliest vertebrates in evolution, is highly conserved compared with mammalian in molecular characterization and physiology fuction. Meanwhile they have some special features of their own. Thorough research on MCRs will contribute to our understanding of vertebrate MCRs evolution and its regulation functions in fish physiology. To facilitate the study on MCRs, we provide a review about clone, molecular characterization, pharmacology and physiological function of fish melanocortin receptors and highlight progress made in these areas.