Abstract:phosphorylase plays a key role in the metabolism of glycogen, a molecule critical for the growth and development of oysters. We evaluated the effect of polymorphisms in the glycogen phosphorylase) on growth and glycogen content. We tested the association between single nucleotide polymorphisms (SNPs) in coding regions of the gene and growth performance (shell height, shell length, shell depth, total weight and soft-tissue weight) and glycogen content using 322 oysters from five full-sib families. We identified 82 SNPs in the 1 940 bp gene, including 63 SNPs in the exon region, one SNP locus located in the 5′-UTR, and 18 SNPs in the 3′-UTR. The average density of SNPs in the coding region was one per 25 bp. Five SNPs were significantly associated with growth performance (<0.05), but there was no association between the SNPs and glycogen content. Furthermore, among the six SNP haplotypes constructed using the five SNPs above, the total weight of the individuals with haplotype H6 ( was significantly higher than those with the other five haplotypes(, suggesting this haplotype may be the most advantageous in terms of weight gain in . Our results provide basic information for future genetic improvement of growth performance in

Abstract:Marker-assisted selection is commonly used to find molecular markers or genes associated with economic traits that are often controlled by multiple genes and inherited as quantitative traits. Eye diameter (ED) and eye cross (EC) are two of the most important quantitative traits in common carp. They are also important morphological characteristics often used in fish taxonomy. We used a full-sib family (68 individuals) of hybrid mirror carp ( L.) to analyze the correlation between 164 microsatellite markers, obtained from a bacterial artificial chromosome (BAC), with ED and EC. We obtained 401 alleles and 463 genotypes from the 164 markers. We used a general liner model with permutation test (10 000 times) to evaluate the relationship between the genotypes and the two traits. Twenty-two of the SSR markers had significant correlation with ED and/or EC(0.05). Six SSR markers, including CAFS1526, were significantly correlated with ED(0.05) and 11 SSR markers, including CAFS0882, were significantly correlated with EC(0.05), and CAFS1298 and CAFS1423 were highly significantly correlated with both ED and EC(0.01). The genotypes at each marker related to the two traits were obtained using Duncan’s multiple comparison test. The markers significantly related to ED and EC were assigned to a linkage map, and nine markers were consistent with the QTL mapping for ED or EC, which explained 13.3–20.9% of the phenotypic variance. These functional markers from the BAC and its genotypes may be used for both MAS and constructing an integrated linkage map with a physical map of the common carp.

Abstract:was expressed in all seven tissues we examined in both sexes. Expression was significantly higher in the male Dmrt4 in the gonads of was higher than in normal males. However, there was no significant difference between normal females and the high temperature-treated neo-males. This indicates that was expressed at significantly higher levels during the gastrula stage than during other stages. was expressed at higher levels in males than in females. Our results provide a molecular basis for the formation of all female groups of .

Abstract:species, belonging to the family Nemipteridae, order Perciformes, are widely distributed in the tropical and subtropical waters of the Indo-Western Pacific. Morphologically, a number of closely related species share similar external coloration and patterns, resulting in difficulty identifying and classifying them based on morphological evidence alone. Despite this, priorevaluation of has primarily relied on morphological data, with few molecular phylogenetic data currently available for this genus. We analyzed the molecular phylogenetic relationship among seven common species collected from the Indo-Western Pacific. Partial sequences of the 1st intron of the S7 ribosomal protein gene were obtained for seven species. We used sequence data from sequences ranging from 734 bp to 746 bp and homologous sequences of 743 bp were obtained for phylogenetic analysis after alignment. Of the 743 bp aligned sequences, 386 sites were conservative, 351 sites were variable, and 289 were parsimony-informative. The content of A+T (54.1%)was lower than that of G+C (45.9%). The genetic distance among the seven , calculated using a Kimura two-arameter model, were between 0.042 and 0.294. We observed a number of insertions and deletions in the S7 ribosomal protein gene sequences. The insertions and deletions at 167 bp, 182 bp, 474 bp, 608 bp, 662 bp within , and at 227 bp, 332 bp, 401 bp, and 604 bp within were identical. We constructed molecular phylogenetic trees using the maximum likelihood and Bayesian inference methods. The seven N. japonicus and N. bipunctatus and were clustered in a separate clade. These phylogenetic relationships were consistent with their morphological classifications. However, the phylogenetic position of Nemipterus species were divided into two morphologically distinct groups according to the length of upper and lower caudal fin lobes. The two lobes are of equal length in have an elongated trailing filament from their upper caudal fin and the upper fin lobe is longer than the lower. Our results suggest acombination of more morphological and molecular evidence is needed for further phylogenetic studies of the genus.

Abstract:) by applying hydrostatic pressure to the eggs of Japanese flounder following fertilization with UV-treated sperm from red sea bream (used as a mapping family). We measured the size of six component elements of the cephalocaudal axis, including body length, head length, dorsal fin length, pelvic fin length, caudal peduncle length, and caudal length. The values for these six traits were all normally distributed and were significantly correlated (<0.01).We documented 22 quantitative trait loci (QTL) controlling the six growth-associated traitsusing MapQTL4.0. These QTLs were mapped on 10 of 24 linkage groups. Among these, four QTLs were correlated to body length, three to head length, four to dorsal fin length, three to pelvic fin length, seven to caudal peduncle length, and one to caudal length. The LOD values of these QTLs varied between 2.01 and 3.68, which explained 3.7%–12.6% of the phenotypic variation. QTLs for body length and caudal length were co-localized; and QTLs for body length, dorsal fin length, and pelvic fin length were also co-localized. Our results provide insight for further selective breeding research and breed improvement.

Abstract:throughout the coastal areas of North China. In recent years, the species has exhibited growth rate depression, decreased fertility, and decreased disease resistance because of a number of factors, including changes in the environment and decreased quality of parent fish. Thus, the development of fast-growing offspring by crosswould aid the sustainable development of the with the traits of disease resistance and fast growing and Korea stock (KS) to establish 24 families, including a “Ping You NO.1” family. We measured thetotal length and body weight of these families at 450 days after hatching. We estimated theheritability of total length and body weight using a . The breeding value of all animals at 450-day was predicted using best linear unbiasedThe heritability of total length and body weight were 0.266 and 0.302, respectively,traits have moderate heritability. The correlation coefficients between breeding values andphenotypic values of the growth traits<0.01). Both growth and breeding ability were higherin Ping You No.1 than in the other families. We used a selection standard of ~30%, and found that 71.43% families of all were the same, selected based on breeding value and phenotypic value, respectively. Comparison of selection efficiency based on breeding value or phenotypic value revealed that the breeding value was better than the phenotypic valuefor growth traits: 35.38% to total length and 32.29% to body weight.

Abstract:(♂) using microsatellite markers. We selected 21 loci with different-sized alleles in from 86 pairs of microsatellites. These loci contained 59 alleles, including 22 specific alleles in . The observed heterozygosity was higher in the F₁ (=0.739) generation. Conversely, the effective number of alleles(2 were similar to those in F₁(=2.45, PIC=0.489). Heterozygous alleles were observed at all loci in the F₁, whereas we found evidence of allelic separation at F₂ loci. Eighteen loci followed strict Mendelian segregation (chi-squared: 1>) exhibited segregation distortion () exhibited non-segregation. Among the 18 Mendelian loci, the F₂ possessed the similar allelic frequencies for specific alleles (47.7%). The genotype frequencies of F₁ type, type observed iwere 58.2%, 19.9%, and 21.9%, respectively. Our results suggest that the F₂ grossly inherited the heterozygosity from F₁, but that there is also a certain degree of separation.

Abstract:. We used MSAP (Methylation-Sensitive Amplification Polymorphism) to analyze methylation patterns of genomic DNA in the muscle, gill, and blood of wild and cultivated “Huanghai No.1”, a strain selected for faster growth rates and improved disease resistance. DNA methylation is closely linked to biological events, including chromatin inactivation, transgene silencing, genomic imprinting, and control of parasitic DNA elements. Because of its efficiency and competence, the MSAP technique has been increasingly used in genomic DNA or individual functional genes studies to analyze DNA methylation levels. We used 30 pairs of selective-amplification primers. Using polyacrylamide gel electrophoresis, we estimated the methylation ratios in the muscle, gill, and blood of wild stock were 23.1%, 22.3%, and 19.7%, respectively, and 21.4%, 19.6%, and 18.9%, respectively, in cultured shrimps. These levels are much lower than in some plants and animals, perhapsbecause of differences in the amount of genomic DNA. The methylation levels at the CCGG site differed among different tissues of the same stock and between the same tissue among different stocks. The level of methylation in genomic DNA was always higher in the organs than in the blood. We observed variation in the DNA polymorphic methylation between wild and “Huanghai No.1” stocks in the blood and gill, but not in the muscle. Furthermore, polymorphic methylation was associated with demethylation and methylation of CCGG loci. Additional research is needed to understand the biological meaning of variation in methylation among CCGG loci. Our approach provides a basis for further studies on the mechanism of methylation-mediated DNA methyltransferases in .

Abstract:an economically important shellfish species in southern China. However, intensive culture practices have resulted in genetic degradation (e.g., inbreeding depression). In addition, there has been a recent increase in the mass mortality of during the post-larval and grow-out stages, resulting in a decrease in production. To address this, genetic improvement is likely to play an important role in the sustainable development of the aquaculture industry. Narrow-sense heritability(h²) provides an index of additive genetic variation. The index is a key indicator of the degree of genetic improvement in an unknown natural population with putative commercial value. We estimated the heritability of shell length, shell width, and body weight of by means of intra group correlation of full-sibs.Twelve half-sib families and thirty-six full-sib families of were obtained by artificial fertilization of three females by single males based on an unbalanced nest design. Each full-sib family was reared separately and all families experienced environmental conditions that were as similar as possible. A random sample of 30 individuals from each family was harvested and the shell length, shell width, and body weight of each individual was measured 40, 120, 180, and 240 days after hatching (dph). The genetic parameters for shell length, shell width, and body weight were estimated with a single trait animal model using the restricted maximum likelihood method. The estimates of narrow-sense heritabilities ranged from 0.13±0.09 to 0.56±0.15 for shell length and 0.13±0.06−0.62±0.13 for shell width. The heritability of body weight was between 0.18±0.15 and 0.26±0.08. We observed a significant positive genetic and phenotypic correlation (correlation coefficient ranges: 0.85–0.98 and 0.66–0.94, respectively)among shell length, shell width, and body weight. Our results suggest anyone of the three growth traits can be targeted for selection to improve growth in .

Abstract:We evaluated the hepatoprotective and antioxidant effects of silymarin (SM) against carbon tetrachloride (CCl₄)-induced hepatocyte and liver injury in , 100, 300, and 600 g/mL silymarin were added to carp primary hepatocytes before (pre-treatment), after (post-treatment), or both before and after(pre- and post-treatment) incubation of the hepatocytes with 8 mmol/L CCl₄ in culture medium. We then measured lactate dehydrogenase (LDH), glutamate pyruvate transaminase (GPT), glutamate oxalate transaminase (GOT), superoxide dismutase (SOD), and malondialdehyde (MDA) levels. carp were fed a diet containing one of three concentrations of silymarin [0.1, 0.5, or 1 g/kg (diet)] for 60 d. Each fish was then given a single intraperitoneal injection of CCl₄ (30% in oil), and 72 h after the injection, we collected blood and liver samples from each fish. We measured the serum biochemical indices and liver tissue indices described above. Silymarin improved cell viability and decreased GPT, GOT, LDH, MDA, and SOD activity. Administration of silymarin at 0.5 and 1 g/kg diet for 60 d prior to CCl₄ intoxication significantly decreased GPT, GOT, in the serum, and increased SOD, glutathione peroxidase, catalase, glutathione, total antioxidant capacity, and MDA formation in liver tissue. However, these parameters, except for LDH, were not significantly altered in fish fed 0.1 g silymarin per kg diet. Our data suggest that silymarin -induced hepatotoxicity in fish, which is likely related to its antioxidant activity. We suggest that silymarin may be used as a hepatoprotective agent against fish liver diseases.

Abstract:Chitooligosaccharide (COS), which is one type of the oligosaccharides, is produced from chitin or chitosan by chemical or enzymatic decomposition methods. Some studies in fish regard that adding COS in dietary could produce beneficial effects on growth performance, nonspecific immune, or blood profiles. about which was effected by COS on promoting growth performance and intestinal microorganisms and =450, average initial body weight=3.02±0.16 g) into 5 groups consisting of triplicate (=30 fish/replicate). Each group was hand-fed a diet containing either 0 (control group), 0.10%, 0.30%, 0.50% or 0.70% COS to satiation three times daily for 8 weeks, and fish were reared in 400 L aquaria with the temperature of (27±2intestinal microorganisms, nutrient16.17% and 9.47%All groups with COS significant increases in specific growth rate (SGR) and the digestibilities of dry matter and protein whereas feed conversion ratedecreased significantly Compared with control group, intestinal villus width increased by 45.21% and 54.06% ( Lacto bacillus of juvenile tilapia (0.05). Results above showed that additional COS improved the intestinal environment and the growth performance, therefore the appropriate addition is 0.30%~0.50% diet of juvenile GIFT tilapia.

Abstract:), and that the pheromones are likely detected through the olfactory system by 17α-P receptors (PRs) and PGE₂ receptors (EPs). During the spawning season, after mature for 24 h and 48 h, we measured the ovulation rates and quantified the immunoreactivities of PR and EPs in the olfactory system using SABC immunocytochemistry. The ovulation rates of females increased after exposure to 17α-P or PGE₂ for 24 h and 48 h. Furthermore, the rate was the higher after 48 h exposure than after 24 h exposure. The increase in numbers of PR and EPs immunoreactive cells was the highest in the olfactory epithelium, followed by the olfactory bulb, and the olfactory nerve was the lowest exposed to 17α-P or PGE₂. The increases in the number of PR and EPs immunoreactive cells were consistent with the increases in ovulation rate. Our results suggest that water-borne 17α-P and PGE₂ affect the reproductive status of and EPs in the olfactory system. We also discuss the potential mechanisms of sex pheromone reception and transduction in the olfactory system.

Abstract:We evaluated the effects of salinity and alkalinity on growth, feeding, and gill microstructure in juvenile (control group), 2.0, 4.0, 6.1, 7.8, 10.0, or 11.9 for 60 d with temperature of 22. The body length, body weight, and specific growth rate (SGR) of juveniles were significantly lower in fish held at salinities <6.1 than in those held in salinity >6.1(<0.05). The maximum final body weight was highest in the fish reared at 2.0. The specific growth rate of weight (SGRW) and feed conversion efficiency (FCE) were highest in fish held at 4.0 and lowest in fish held at 11.9. Our results suggest the optimal salinity for growth is 1.88, whereas exposure to levels 7.8 results in negative effects. Fish were also reared at 10.00, 15.83, 25.10, 39.80, and 63.12 mmol/L NaHCO₃. The body weight, length, and the SGR of juveniles reared in water with <25.10 mmol/L NaHCO₃were significantly lower than in the remaining groups (0.05). The largest final body weight, body length, SGR, SGRW, and FCE were in fish reared at 15.83 mmol/L NaHCO₃.The fish reared at 63.12 mmol/L NaHCO₃ had the lowest values for all indices. Rearing in water with NaHCO₃ levels >39.80 mmol/L had negative effects and the optimal alkalinity for growth was 20.57 mmol/L. Observation of gill microstructure revealed hypertrophy in the chloride cells, and both hypertrophy and edema in the epithelial cells as salinity and alkalinity levels increased, thereby affecting the growth of the fish. In conclusion, the salinity should bebelow 6.1 or the alkalinity should be below 25.10 mmol/L in the larvae culture.

Abstract:parent Kaluga were captured from the Amur River and mated. We documented development between the (12.08 ± 0.68) mm(129.21 ± 7.69) mm]. The development was divided into two phases, the prelarval stage between hatching and first feeding(09 dah), and the postlarval stage between the initiation of external feeding and completion of anterior to the anus The morphological development and differentiation were more rapid in prelarvae than in postlarvae. During the prelarval stage, a range of swimming, respiratory, sensory, and feeding organs presumably enables prelarvae to forageFurther differentiation and development of bone plates, further development of fins, and appearance and development of the swim bladder changes occurring during this latter stage likely lead to further improvements in the ability of fish to forage and avoid predators

Abstract:) are an endangered anadromous species listed on the IUCN Red List. The species was characterized as a national level key protected animal of China in 1988 and fell under the protection of CITES Appendix II in 1998. Because of their perilous status, there is considerable interest in artificial breeding and species conservation. To aid development of conservation breeding programs, we evaluated the effects of cultured at three stocking densities (low: 1 g/L, medium: 4 g/L, high: 8 g/L) for 40 d to evaluate the influence of stocking density on on growth and feeding. The body weight, growth efficiency, specific growth rate, and daily weight gain decreased significantly increased. The feeding rate for the experimental groups also decreased as the stocking density increased and the feed conversion ratio increased as the stocking density increased. Density also had a significant effect on behavior because of chronic crowding stress. The breathing frequency, tail wagging frequency, and swimming distance increased with an increase in stocking density.

Abstract:; testosterone, T), protein phosphorus (SPP), and protein calcium (SPC). In addition, we quantified ) mRNA expression in the liver and ovary. We observed phase ℃did not develop beyond phase II by the end of the experiment (6 weeks). The majority of the indices increased with treatment time, except the hepatosomatic index (HSI). Temperature had no effect on the levels of testosterone. The gonadosomatic index (GSI) and E₂ levels were significantly elevated in fish held at 23℃<0.05). The levels of SPP were higher in fish held at 23°C and 26 group, but the difference was only significant for the group held at 23mRNA expression was lower in the ovary than in the liver. The effect of temperature on liver levels. However, ovarian mRNA expression was only significantly higher in the 26 group. In summary, the optimal temperature for the ovarian development of . In addition, there is a significant positive correlation between liver content

Abstract:Mussels are often used as sentinel organisms to monitor the presence of environmental contaminants. We measured the (HCH) content in the soft tissue of oyster (Gould) samples collected from the Guangdong coast in 19892012 using gas chromatography. Using related data taken from the Pollution Investigations Program along Guangdong’s coastal zone during 1980−1985, we analyzed the residue levels, spatial and temporal trends, and composition of HCHs in oysters. In addition, we assessed the food safety and biological quality of HCHs in oysters. HCHs were detected in 92.3% of the samples at concentrations ranging from below the limit of detection to 42.4 wet weight basis). HCH content has declined over time since the early 1980s, but the rate of decline slowed and levels have remained constant since the early 1990s. In general, the HCH content has decreased by 99.94% over the last 30 years. In the early 1980s, the HCH content in oysters in the Pearl River Estuary was much higher than in the East and west Guangdong coasts, but the difference in HCH content between these three coasts has gradually decreased over time. The composition of HCH compounds implies that the HCHs are primarily derived from historical usage, but the lower ratios of -HCH/-HCH (0.531.11) indicate that there was likely fresh input of lindane between the 1990s and early 2000s. The HCH residue levels in all oyster samples were far below the maximum residue limit in China, although 75.0% of oyster samples collected in 1989 exceeded the requirement of the first grade of the National Marine Biological Quality Standard of China (GB18421-2001). The daily intake of HCHs by residents along the Guangdong coast via , which is much lower than the Acceptable Daily Intake established by the Food and Agriculture Organization of the United Nations/World Health Organization.

Abstract:Eriocheir sinensis during the fishing season in Jiuduansha, Yangtze River estuary, between 2006 and 2011. The annual yield ranged from 93.3 to769.5 kg/ship (mean: 481.5 kg); the average daily catch ranged from 6.2 to 26.5 kg (mean: 18.5 kg); the total number of crabs captured ranged from 984 to 7 547 (mean: 4 129); the average individual weight ranged from 89.5 to 114.5 g/ind (mean: 100.7 g/ind); the percentage of male crabs ranged from 65.80% to 80.54% (mean: 74.35%); and the average yield of the ships tended to fluctuate among seasons, but generally increased over time with a peak in 2010. The average harvest weight declined after initially increasing, and peaked in 2008. The maximal daily catch generally occurred in early December, but was as early as November 24 (in 2009) and as late as December 12 (in 2010). The percentages of fishing occurring in the early fishing season, peak fishing season, and late fishing season ranged from 4.25%–38.48%, 37.92%–72.81%, and 1.77%–34.00%, respectively. At the beginning of fishing season, the large crabs constituted a higher percentage of the catch and male crabs were more abundant than females. However, the quantity of small crabs in the harvest increased and the size of crabs tended to decrease over time during the seasons. Furthermore, the percentage of female crabs in the harvest increased during the season, resulting in a similar total harvest of male and female crabs. The total catch was significantly correlated to water temperature and tides. Typically speaking, the peak fishing season period starts when the water temperature reaches ~13and the maximal daily catch occurs in temperatures ranging from 10–13.5 The majority of harvest occurred during low tides (maximum: 95.79% in 2008, minimum: 73.41% in 2010).

Abstract:Knowledge of taxonomic diversity is critical to understanding the taxonomic relatedness of species and unevenness of taxonomic structure. We evaluated the temporal and spatial variation in taxonomic diversity of fishes in Haizhou Bay, China using data collected from five comprehensive surveys of the bay between March–December, 2011. We used a generalized additive model (GAM) to analyze the relationship between taxonomic diversity of fishes and environmental factors. We identified 96 fish species in HaizhouBay, belonging to 2 classes, 13 orders, 44 families, and 71 genera. The average taxonomic distinctness () was 79.5 and the variation in taxonomic distinctness () was 200.6. Both these taxonomic diversity indices exhibited seasonal and spatial variation related to the seasonal migration of fishes and changes in the environment. Water depth and benthic levels of dissolved oxygen had a significant effect on the of fishes. Similarly, water depth, benthic levels of dissolved oxygen, benthic water temperature, and month were the most important environmental factors influencing the of fishes in Haizhou Bay. The two taxonomic diversity indices decreased along a line from north to south, suggesting that latitude has an important influence on the spatial distribution of taxonomic diversity in fishes.

Abstract:The widespread use of antibiotics in aquaculture has led to increasing problems caused by bacterial resistance. Given this, there is an urgent need to develop a medication regimen that prevents the formation of drug resistant bacteria. We estimated a number of pharmacodynamic (including mutant prevent concentration and mutant selection window)and pharmacokinetic parameters for the antibiotic drug enrofloxacin. Our objective was to develop a medication regimen against hemorrhagic septicemia in crucian carp(The minimal inhibitory concentration (MIC) was 0.125 μg/mL, the post-antibiotic effect (PAE) of enrofloxacin on the pathogenic bacterial strains was observed up to (1.67±0.42) hmutant prevention concentration (MPC) was 1.125 μg/mL, and the mutant selection window was between 0.125 and 1.125 μg/mL. We developed integrated enrofloxacin concentration-time curves for the serum of crucian carp following administration of a range of doses. Enrofloxacin persisted in the serum at concentrations above the MPC for 5 h at a dose of 5 mg/kg; 9.5 h at a dose of 10 mg/kg, and 23 h at a dose of 20 mg/kg. The serum PK/PD parameters AUC₂₄/MIC and /MIC were 137.22 and 15.05, respectively, at a dose of 5 mg/kg, 285.25 and 41.43, respectively, at a dose of 10 mg/kg, and 426.25 and 52.32, respectively, at a dose of 20 mg/kg.The drug remained in the plasma with a concentration >MPC for (24-PAE) h and AUC24/MICemorrhagic septicemia can be controlled , at intervals of 24 h.The proposed withdrawal time in crucian carp should not be less than 25 d. The methods described in this study also can be used for developing dose guidelines for other anti-bacterial drugs to prevent selection for drug-resistance.

Abstract:Recent research suggests hemocyanin acts as an immunologically multi-functional protein in invertebrates. However, little is known about the antibacterial activity of hemocyanin. We evaluated the antibacterial activity of this hemocyanin and its binding target to pathogens using antibacterial and antibacterial inhibition assays. The hemocyanin exhibited antibacterial activity against K12. This activity was completely or partly inhibited by the outer membrane proteins of hemocyanin against K12 Omp-deletion mutants of OmpW was significantly lower than that of the control. Together, our results suggest that hemocyanin exhibits antibacterial activity by binding to a range of outer membrane proteins

Abstract:We determined the effect of stress on the structure, number and morphology of cells in the head kidney with those of control fish (unstressed). In unstressed animals, the head kidneyconsisted ofnormal and regularly distributed lymphatic tissue, hematopoietic tissue, blood vessels, melano-macrophages, and interregnalmelano-macrophage enlargement of the interrenal cellular and nuclear areas and nuclear diameter in 24 h after exposure to the handling stress, there was a decrease in the number of melano-macrophages and in thesize of the interrenal cellular and nuclear areas and nuclear diameter,We identified six typeserythrocytes, lymphocytes, monocytes,neutrophilic granulocytes, basophilic granulocytes, and thrombocytes in the head kidney of control fish. The handling stress led to an erythrocytes. Interestingly, the number of erythrocytes, neutrophilic granulocytes, and basophilic granulocytes decreased continuously after the stress, whereas the number of lymphocytes and monocytes increased 0.1 h after the stress but then decreased, while the number of thrombocytes increased at all times after the stress. Our results suggest that stress significantly affects the structure and cell morphology in the head kidney. We also noted the return of normal biological function within 24 h for several of the indices.

Abstract:We evaluated the isothermal distribution of subsurface temperatures in the bigeye tuna () fishing grounds in the tropical Indian Ocean. We plotted the isothermal depths at 10, 12, 13on a spatial overlay map using data collected on monthly basis from Argo buoys and monthly CPUE (catch per unit effort) from bigeye tuna long-lines. In addition, the differences in depth between the 12 and 13isolines at the lower boundary of the thermocline were computed to determine the relationship between bigeye tuna vertical distribution and thermocline depth. Our analysis suggested that the vertical range of optimal temperatures (10 and 16) in the area of high CPUE was between 150 and 400 m, and was beneath the lower boundary depth of the thermocline. The overlay maps suggest that CPUE is highest in areas where the 12 isothermal depth is shallower than 350 m (mode: 225−350 m). Conversely, if the depth is >300 m, the CPUE tends to be low. Similarly, the highest CPUEs were observed in areas where the 13 isothermal depth was shallower than 300 m (mode: 190−275 m), whereas CPUE was low when the depth exceeded 400 m. The vertical distribution of high hook rates was concentrated in the area to the north of 15°S. We used a frequency analysis and the empirical cumulative distribution function to compute the optimum range of subsurface factors. The optimum ranges for the12isothermal depths were between 250−340 m and 190−270 m, respectively. The optimum depth difference ranges were 30–130 m for the 12 isothermal depth. We documented the distribution interval and vertical depth range for the central fishing ground of bigeye tuna. Our results provide a reference for improving the efficiency of thelong-line fleet and aiding in resource management.

Abstract:We evaluated the relationship between sinking depth and a number of factors using multiple regression to determine the external patterns of sinking a purse seine. We collected data on sinking depth, gear operation, and shooting duration(), current direction() length from tuna purse seiners owned by Shanghai Fisheries General Corp. between September and December in 2011. Current direction and shooting velocity had no effect on sinking depth (). Conversely, the shooting duration, current speed, and length of the purse line had a significant effect on sinking depth (158. Principal component analysis suggested that the majority of factors associated with gear operation have little effect on the sinking depth. Under normal operating conditions (shooting duration: 550 s ,purse line length: 2 000 m), the model predicts that the average sinking depth is 236.78 m with a95% confidence interval ranging from of wind and currents. Similarly, the % confidence interval: 60.56 to 123.97 m)

Abstract:using a routine method including intraperitoneal injection of PHA and colchicine, air-drying, and staining. In addition, we determined the erythrocyte nuclear DNA content of using flow cytometry, with chicken erythrocytes (2.50 pg) as a standard. The diploid chromosome number of was 2n=100, and the karyotype was 2n=. The secondary constriction, satellite chromosomes, and heterosomes were not observed. Silver staining revealed that most chromosomes featured a pair of Ag-NORs. The ranged from 1 to 2 in the interphase nucleus, but Ag-NOR combinations were not observed. We estimated the diploid cellular DNA content of , and is a member of the primitive fishes in the specific classification order.