Abstract:Cell proliferation plays important roles during metamorphosis in flatfishes. As an epithelial mitogen, epigen can promote cell proliferation in a dose dependent manner via stimulating phosphorylation of the EGFR and downstream signaling molecules such as the mitogen activated protein kinase (MAPK). Q RT PCR result in a previous study showed that epigen expressed higher in early stage of metamorphosis, and became low in climate stage of metamorphosis. To further investigate the relationship between epigen expression and metamorphic events in Paralichthys olivaceus，we employed whole mount in situ hybridization to detect the expressional pattern of epigen gene during metamorphosis. The results indicated that epigen expressed universally in various tissues. The expressional signal of epigen in larvae during pre metamorphosis to Stage E was strong, then became weak after Stage F. It was observed that epigen expressed mainly in gill, liver, intestines, fin, actinost, myotome and epidermis. Tempo spatial expressional patten of epigen gene in P. olivaceus indicates that it might participate in some metamorphic events, particularly in those events that happened during early stages of metamorphosis.

Abstract:To reveal the gene sequences of prolactin and its expression in osmotic regulation tissue of Cyprinus carpio var.Jian, the full length cDNA encoding prolactin was cloned from Cyprinus carpio var.Jian using homology cloning and RACE PCR approach. The prolactin was 1 028 bp in length, including 51 bp 5’terminal UTR, 633 bp encoding region and 344 bp 3’terminal UTR. Phylogenetic analysis using MEGA 4 software showed that the putative prolactin amino acid sequence and other teleosts have the high similarity of 55.02%-94.76%. The prolactin amino acid sequence of Cyprinus carpio var.Jian and that of Ctenopharyngodon idella were close to each other in similarity of 94.76%. For other fishes, the similarity was 94.26%，90.00%，70.53%，70.53%，65.70%，63.90%，63.29%，62.93%，62.38%，62.32%，55.02% with Schizothorax prenanti, Danio rerio, Salmo salar, Oncorhynchus mykiss, Anguilla japonica, Oreochromis Niloticus, Epinephelus coioides, Acanthopagrus schlegelii, Paralichthys olivaceus, Sparus aurata, Takifugu rubripes, respectively. Real time quantitative PCR results indicated that prolactin genes were expressed in the pituitary, brain, liver, kidney, intestines, gonad, spleen and gills. The prolactin transcript was detected at a high level in pituitary, moderate in brain, gills, spleen, liver, kidney and intestines, and low in gonad. This suggests that the pituitary gland is the main expression site of prolactin in Cyprinus carpio var.Jian.The prolactin transcript was detected in the gonads, liver, and spleen suggests that there may exist many physiological functions about prolactin in fish.

Abstract:In this study, Roche 454 high throughput technology was used to conduct transcriptome sequencing and establish ESTs database of the largemouth bass northern subspecies and Florida subspecies. The results showed that a total of 468 671 and 332 322 ESTs were generated from northern subspecies and Florida subspecies. The average length was 306.5 bp and 304.4 bp, respectively. Assembly of the largemouth bass northern subspecies and Florida subspecies’ high quality ESTs resulted in 42 056 and 35 743 contigs. The average length was 612.6 bp and 588.2 bp, respectively. EST database of largemouth bass northern subspecies and Florida subspecies was merged and then compared with known protein databases. 78 938 EST sequences in total were annotated. By exploring the merged largemouth bass EST library, over 25 469 and 8 547 putative SSRs and SNPs were identified. Comparison of the northern subspecies and Florida subspecies sequence was made by randomly selecting 75 contigs from the EST database. Results showed that EST sequences of the two subspecies homology were 99.2%. 

Abstract:Fourteen polymorphic microsatellite loci were isolated from the Japanese smelt (Hypomesus nipponensis). These microsatellite markers were tested in a sample of 24 individuals. The number of alleles ranged from 3 to 25, with an average of 8.4 alleles per locus. The observed and expected heterozygosity of these loci varied from 0.266 7 to 1.000 0 and 0.282 5 to 0.932 2, respectively. Locus HN 075 and HN 250 deviated significantly from Hardy Weinberg equilibrium (P<0.05). No genotypic disequilibrium among loci was found (P<0.05). These microsatellite markers could be useful in studing population structure of the Japanese smelt, or introduction routes of this fish to China.

Abstract:From May to September in 2010, water quality parameters such as water temperature, total dissolved salt, dissolved oxygen, pH, transparency, nitrite nitrogen, ammonia nitrogen, nitrate nitrogen, total nitrogen, reactive phosphorus, total phosphorus, chlorophyll a and biochemical oxygen demand were analyzed in 22 Litopenaeus vannamei ponds with different culturing methods in Fengxian District, Shanghai. Water used for Farm No.1 was natural fresh water which had been precipitated before being introduced to the ponds. Mixed salt were added to the fresh water for culturing shrimp in Farm No.2. Results were as follows: water temperature, dissolved oxygen and pH didn’t change dramatically and could match the demand of Litopenaeus vannamei. The proportion of nitrate nitrogen in ponds to TIN was the highest, the ratio of ammonia nitrogen to TIN increased with time extension, and that of nitrite nitrogen to TIN increased obviously in the later period of culture cycle. Contents of reactive phosphorus decreased gradually while the total phosphorus increased in the whole process of culture. Biochemical oxygen demand and chlorophyll a also increased gradually with the shrimp growing up. Muscle nutritional quality of Litopenaeus vannamei from the two farms were analyzed and the results were as follows: contents of crude protein and crude fat of shrimp muscle in Farm No.1 were 16.30% and 1.42% respectively, lower than those in shrimp muscle from Farm No.2 which were 18.30% and 1.61%. Content of total amino acids in shrimp from Farm No.1was 23.27%, and the essential amino acid was 9.09%. While those in shrimp from Farm No.2 were 27.52% and 10.74%. Contents of flavor amino acids in shrimp from Farms No.1 and 2 were 8.52% and 10.16% respectively.

Abstract:Kinds of digestive enzymes activities were studied in Nibea japonica of the early development stage. The results showed: amylase, lipase and alkaline phosphatase activities can be detectable during embryonic development stage, while pepsin and acid phosphatase could not be detected. Activities of amylase, lipase and pepsin changed significantly with the growth of fish larvae, amylase and lipase activity in the larvae increased rapidly after hatching, and reached the higher level before first feeding stage, mounted respectively (0.433 ± 0.010) U/mg and (388.53 ± 16.16) U/g. It showed that kinds of digestive enzymes had existed in the body of Nibea japonica for the preparation of their food intake, which could help the digestion of carbohydrates and lipids. The activities of pepsin were earliest detectable in the 8d larvae, specific activity was valued at only (0.33 ± 0.09) U / mg. The activities rapidly increased during the later 15 days, and reached the highest value in the 23 day larvae, amount（1.83±0.12）U/mg. The weak alkaline phosphatase activity which could detected in the fertilized eggs increased slowly after hatching, and it reach the peak value (156.74± 5.17) U / g in the 13 day larvae, afterward the values stabilized at a higher level, which indicated that intestine was the main digestive place, and its digestive function had been perfected gradually during the development of Nibea japonica larvae.

Abstract:The tolerance to low water temperature, oxygen consumption rate and asphyxiation point were compared among northern largemouth bass, florida largemouth bass and their reciprocal hybrids. The results were as follows: when the acclimation temperature was 20 ℃ and the rate of temperature decrease was 2 h/℃,the low semi lethal temperatures of northern largemouth bass was the lowest(3.1±0.17) ℃, florida largemouth bass was the highest(5.05±0.21) ℃.One way ANOVA analysis indicated that there were significant differences(P<0.05) in the tolerance to low temperature of four largemouth bass species.The oxygen consumption rate and asphyxiation point of four largemouth bass species were studied.The result demonstrated that,under the natural water temperature(24-27℃), the oxygen consumption rate were 0.136 8 mg/(g·h),0.181 1 mg/(g·h),0.168 1 mg/(g·h) and 0.138 8 mg/(g·h), respectively. There were no significantly difference for the oxygen consumption rate at the four groups in day and night. Under constant temperature 15 ℃,the asphyxiation point of them were 0.33 mg/L,0.40 mg/L,0.38 mg/L and 0.34 mg/L, respectively.There was no significantly difference between the oxygen consumption of the four largemouth bass species(P>0.05).

Abstract:More than 100 countries and regions are rearing tilapia now, and the global annual output of tilapia has reached about two million tons. Tilapia is one of the products having an edge for export in China. Over the past decade, the tilapia production in China has been increasing at an average annual rate of about 9%, ranking first in the world. To understand the current situation of standardization of tilapia industry, and to survey the applicability of current working standard in the tilapia industry, the subject study group investigated the overall process of tilapia production and circulation in China by paying a site visit, collecting data, and distributing questionnaire etc. in Guangdong, Guangxi and Hainan Provinces, which are the main producing regions of tilapia aquaculture. The subject study group has already learned the potential hazard in all links of tilapia industry, such as water quality for rearing tilapia; tilapia germplasm, fry and broodstock; selection of feed and feeding; disease control and medication; sanitation and hygiene of transportation equipment; and processing and packing, etc. Actual application of the standard was investigated, the missing standards and those needing to modify were listed systematically. After research and analysis of the standards of healthy culture and quality safety, which are currently applied in advanced countries, and in combination with the actual demand and research situation of tilapia industry in China, 4 standards to be established and 6 standards to be revised were proposed to provide guarantee for healthy development of tilapia industry.

Abstract:In the previous studies on the antibiotic sensitivity of Porphyra, the somatic cells isolated enzymatically from Porphyra gametophytic blades were often used. However, the accurate analysis of antibiotics effects on the survival, growth and development of the somatic cells was difficult, because the somatic cells isolated even from a Porphyra blade had different regeneration capacity, cell division and developmental pathways when they were culturedin vitro. In this paper, the antibiotic sensitivities of Porphyra yezoensis conchospores which are almost the same in viability, germinability and developmental pathways, were studied by treatment with kanamycin, ampicillin and chloramphenicol. The obtained results demonstrated that kanamycin could promote the growth and development of conchospore germlings. After 7 days of culture, the cell number of 26% of the conchospore germlings was over 20 cells, which was twice as many as that of control group. After 11 and 18 days of culture, the mean length of conchospore germlings was 1.6 times and 2.1 times longer than that of control group, respectively. The treatment with ampicillin could inhibit the growth and development of conchospore germlings, showing decrease of cell division rates and inhibitation of germling development. After 7 days of culture, the cell number was less than 15 in 80% of conchospore germlings. After 11 and 18 days of culture, the mean length of conchospore germlings was shorter than that of control group, as ampicillin concentrations increased. The chloramphenicol had strong lethal effect on conchospore germlings. When chloramphenicol concentration was higher than 100 μg/mL, the conchospore germlings died out after 7 days of culture. The conchospore germlings treated with 50 μg/mL of chloramphenicol also died out after 11 days of culture. The cell number was less than 5 cells in 90% of the dead conchospore germlings. Therefore, it was concluded that the chloramphenicol is an effective selective pressure in genetic engineering of P. yezoensis.

Abstract:Four diagnostically challenging cases of unknown hepatopathy in four female diamondback terrapins（Malaclemys terrapin） are reviewed and important differential diagnoses discussed. The methods are necropsy，blood smear and histopathological section. At necropsy, the livers were dark，atrophied, and the capsule fibrotic. Abnormalities noted in the hemogram are eosinophilia. The number of leukocytes and eosinophils was significantly higher than normal ranges for healthy reptiles. The pathological changes of livers are the most serious and have consistency. Granular degeneration and vacuolar degeneration happened in most hepatic parenchyma cells, and seriously even necrosis. The hepatic veins lined by inflammatory cells and hepatic congestion. At the end, the most hepatic parenchyma cells were necrosis except the portal area. The lesions in eyelids, lung and kidney are mild and not enough to threaten life，and were complications. The lesion in the four terrapins was diagnosed on these results as a hepatopathy, and the terrapins died of liver failure. There is no evidence to prove that is a parasite infection.

Abstract:Macrobrachium rosenbergiinodavirus (MrNV) and Macrobrachium rosenbergii dicistrovirus (MrDV) are the main viral pathogens of Macrobrachium rosenbergii. In order to detect the two viruses, two pairs of primers targeted sequences located within the MrNV capsid protein gene and MrDV RNA dependent RNA polymerase (RDRP) gene amplified amplicons of 384 bp and 472 bp, respectively. The reaction conditions of the duplex RT-PCR were optimized and PCR products were sequenced. Meanwhile, the specificity and sensitivity of duplex RT PCR were studied. Results reveal that optimum annealing temperature of duplex RT PCR is 60 ℃ and the minimum concentrations of primers are 0.1 μmol/L of MrNV384 and 0.05μmol/L of MrDV472. The detection limit of duplex RT PCR was determined to be 360 fg of tissue total RNA for both the viruses. The two pairs of primers were found to be specific to MrNV and MrDV respectively, and did not to react to either Taura syndrome virus (TSV), White spot syndrome virus (WSSV), Infectious hypodermal and hematopoietic necrosis virus (IHHNV), or Aeromonas hydrophila TPS-30. Sequence analysis of RDRP gene amplicons of MrDV revealed no variations. By contrast, sequence analysis of MrNV amplicons showed many variations in nucleotide sequences of the capsid protein gene. The phylogenetic tree shows that the stains of MrNV, collected from Yangtze River delta in 2011, are from two genotypes, Chinese and Southeast Asia genotypes. This new duplex RT PCR method could be applied for routine health monitoring, early virus detection, and studying virus host interaction, detection of carriers and screening of broodstock.

Abstract:The basal diet(A) contains 25% fish meal as control, and four isonitrogenous isoenergic yeast extract experiment diets, which substituted 15%(B), 30%(C), 45%(D) and 60%(E) fish meal in basal diet, were fed to the Litopenaeus vannamei (7.50±0.13) g respectively for 42 d, then superoxide dismutase (SOD) activity and lysozyme (LSZ) activity in haemolymph and the expressions of lysozyme mRNA and Toll receptor mRNA in gill were detected. The shrimp were also challenged with Vibrio alginolyticus. The results showed that: LSZ activity in haemolymph in 15% group was significantly higher than that of control (P<0.05). There was no significant difference of SOD activity in haemolymph, the expressions of lysozyme mRNA and Toll Receptor mRNA in gill between alternative groups and control group (P>0.05). The cumulative mortality of 60% group at 24 h and 48 h was significant higher than that of control (P<0.05), and there was no significant difference of cumulative mortality between alternative groups and control group at 72 h and 96 h (P>0.05). It is therefore suggested that yeast extract can replace 45% fish meal of the diets without affecting immunity and vibrio resistant ability of the shrimp.

Abstract:The experiment was conducted to study effect of three kinds of feed on growth, immune enzyme, amino acid content and digestive enzymes activity of Procambarus clarkii for two months. The results showed that the Procambarus clarkii’s SOD,CAT activity of biological feed was higher than other groups(P<0.05)，while ACP，LSZ have no significant difference (P>0.05). Three feed has little influence on the composition and content of amino acid in Procambarus clarkii. The composition and content of essential amino acid and the ratio of the total amino acid are not due to the different feed. In addition, biological feed has a little influence on the growth of Procambarus clarkii, the weight gain rate was higher than the other feed’s. At the same time, trypsin and amylase activity were higher than ordinary feed’s, and trypsin activity was significantly different from ordinary feed’s (P<0.05). Therefore biological feed can enhance the Procambarus clarkii’s immunity, improve the viability and accelerate its growth.