The diploid chromosome number, karyotype, and DNA content were studied in metaphase chromosome in kidney cells and blood of blue common carp Cyprinus carpio blue var injected with PHA and colchicin by airdrying technique. It was found that the diploid chromosome number was 2n=100. The karyotype was found to be composed of 30 m, 26sm and 44st＋t chromosomes, and NF=156. The diploid nucleus DNA content was measured from the somatic cell of the blue common carp using flow cytometer （Beckman cellLab Quant, made in USA） and the DNA content （2.3 pg· N^＋） in erythrocytes of chick （Gallus sp） as standard. The common carp had DNA content of3.99pg·N^-1, corresponding to the result measured chromosome number as ploidy.

The chromosomes were prepared in the backcross progenies from female hybrids of common carp and crucian carp crossed with male mirror carp and common carp by injection of PHA and colchieines. Results showed that the genome ofbackcross progenies consists of 150 chromosomes which can be divided into four groups according to the centromere site. Each chromosome subgroup is made up of three homologous chromosomes. The chromosome number of the progenies from the female hybrids of common carp and crucian carp crossed with the male common carp is 3 n = 150, the number of chromosome arms 234,and the karyotype formula 3n = 60m ＋ 24sm ＋36st ＋ 30t. The chromosome number of the backcross progenies from female hybrids of common carp and crucian carp crossed with male mirror carp is 3n = 150,the number of chromosome arms 258, and the karvotvoe formula 3n = 63m ＋ 45sm ＋12st ＋30t.

The wild juvenile skin carp Hemibarbus labeo （Pallas） were collected from the YaLu River and Ai River, and cultured in ponds and net cages for 3~4 years until they became broodstocks. A total of 231 females and 231 males were induced to spaw by injection of the hormone （LHRH-A2＋DOM＋HCG）, and 4700,000 fertilized eggs and 2825,000 fry were obtained in 2009 and 2010. In the study, the techniques of artificial propagation of the skin carp were studied including sexual distinguish, identification of maturity degree, spawning temperature and time, hormone injection, artificial insemination and hatching.

Juvenile lenok Brachymystax lenok were reared in ponds with running water at 2.8-16.8℃.,and had mean body weight of 60.53±27.60g in 12 months, 323.37±74.61g in 24 months, and 735.83±164.80 g in 30 months. The lenok will have marketable body weigh of over 500 g in 24-28 months. The lenok showed better growth in 2-3 years old than in 1 year old. The coefficient varia- tion in body weight wase changed from 20% to 55%.

The types of digestive enzymes were analyzed in digestive tracts of common carp Cyprinus carpio silver carp Hypophthalmichthys rnolitrix, bigheand carp A ristichthys mobilis, grass carp Ctenopharyngodon idellus by polyacrylamide gel electrophoresis, and the relative activities of the digestive enzymes were determined in the fishes by colorimetry and titration.The results showed that the order of the protease activity was arranged as common carp 〉silver carp 〉 bighead carp 〉 grass carp, and that for amylase activity as grass carp 〉 bighead carp 〉common carp 〉silver carp. The digestive enzyme expression in these fishes was found to be paralleled to the histology structure of digestive tracts. The maximal digestive enzymic activity was observed in the 2/5 parts in anterior end of the digestive tract （G1, G2）, where was found to be the main place for digestion in those stomachless fishes, followed by the following 1/5 part of digestive tract （G3）. The minimal digestive enzymic activity was occurred in the last 2/5 parts （G4, G5） of the intestines. The findings provide a theoretical basis for the nutritional physiology, the development of feedstuff and the management for germplasm in these fisheries.

Grass carp Ctenopharyngodon idellus juveniles with body weight of 110±5g reared in a net cage of 1.0m×0.5m×1.0m were fed the basal diets supplemented with different levels ofhypericin （0%, 0.066%, and 0.132%）, chlorogenic acid （0%, 0.04%, and 0.08%） and scleroglucan （0%, 0.2%, and 0.4%） at water temperature of 25±2℃ for 35 days to evaluate the effects of the additives on growth performance and immune ftmction of the grass carp juveniles. The results showed that there were no significant differences in weight gain rate and specific growth rate in the juveniles in all experiments （P〉0.05）.However, the juveniles fed the diet containing 0.08% chlorogenic acid had significantly higher final body weight and hepatosomatic index than the juveniles fed the control diet did （P〈0.05）. All of the additives significantly enhanced the activity of alkaline phosphatase （AKP）, the peak value in the fish fed the diet supplemented with 0.08% chlorogenic acid, and no significant differences in AKP activity among all treatments. There was significantly higher activity of superoxide dismutase （SOD） in 0.132% hypericin group than that in the control, whereas there was no significant difference in SOD between the treatments and the control groups. The grass carp juveniles fed the diet supplemented with 0.2% scleroglucan had significantly higher lysozyme activity. The three additives were not found to affect significantly the content of malondialdehyde （MDA） in the serum.

The relationship between morphometric attributes and body weight ofEsox reichrti Dyhowsk were analyzed on the basis of the measurement of 13 morphometric attributes form 332 E. reichrti in this study. Total length（X1）, standard length（X2）, head length（X3）, snout length（X4）,body width（X5）, head width（X6）, interorbital distance（XT）, body depth（Xs）, head depth（Xg）, caudal peduncle depth（X10）, caudal peduncle length （X11）, oral fissure width （X10）, oral fissure length （Xn）and body weight （Y） were measured. The correlation coefficients and path coefficients were calculated by correlation analysis, path analysis and multiple regression analysis. The results showed that all the correlation coefficients between each independent variable and dependent variable （body weight） were all at significant level （P〈0.05） or extremely significant level （P〈0.01） excepting for the correlation coefficients between head length and body weight of 0^＋ years old. There were some differences on path coefficients of Esox reichrti from different years old. While the pathcoefficients of standard length and head depth to body weight all achieved very significant level （P〈0.01）, among them standard length was the most predominant variable to affect body weight, and it was a key effective factor to body weight. The results of determinant coefficients analysis revealed that the determinant coefficients of standard length gave a predominant determinative effect, whereas the others exhibited a slight direct effect and significant indirect effect on the body weight via standard length. The diversification of determinant coefficients analysis was consistent with that of path analysis. The high value of multiple correlation index R2 〉0.85 between morphometric attributes and body weight suggested that the selected attributes were practical. The morphometric attributes were used to establish the multiple regression equations as LgY = -1.411 ＋ 0.395Lg X8 ＋ 0.576Lg X1 ＋ 0.092Lg X10＋ 0.538Lg X7＋ 0.35Lg X6;LgY = -4.132 ＋ 0.866Lg X1 ＋ 0.102Lg X12 ＋ 0.083Lg X7;LgY -4.186 ＋ 0.772Lg Xj ＋ 0,195Lg X7;LgY = -2.542 ＋ 0.372Lg X1 ＋ 0.185Lg X3 ＋ 0.256Lg X5＋ 0.23Lg X7;LgY =-4.585 ＋ 0.816Lg X1 ＋ 0.178Lg X7 for 0＋ to 4＋years old. This paper provided theoretical evidence and perfect measure target for breeding of E. reichrti in aquaculture.

The body weight, total length, standard length, fork length, body height, body width, head length, head height, head width, eye diameter, interorbital width and snout length were measured in 900 over 1-year old Hucho taimen juveniles from 20 full-sib families. The correlation index （R2）, path coefficients （Pi） and determination coefficients （Di） were calculated based on independent variables of morphometric attributes and dependent variables of body weight by correlation analysis, path analysis and multivariate analysis. There were significant difference in all 11 correlation coefficients between each morphometric attribute and body weight （P 〈 0.05）. Exclusion of standard length, fork length and head length attributes that shared the collinear with total length, the path analysis revealed that the eye diameter and snout length had no significant effect on the body weight. Among the remain six attributes, the total length was found to show the significant effect on the body weight with the direct effect efficiency s of 0.5549. Judging by the results of high determination coefficients （R2=0.9643）, the six attributes were the key effective factors to the body weight. The path formula was expressed based on the independent variables of total length, body height, body width, head height, head width, interorbital width and dependent variables of body weight by using multivariate analysis as log （body weight） =-3.9130＋1.7039 log （total length）＋0.2626 log （body height）＋0.2740 log （body width）＋0.1765 log （head height）＋0.3460 log（head width）＋0.2624 log（interorbital width）. These results provided a theoretical basis with selection of taimen broodstock and measurement of the morphometric attributes in aquaculture.

The enzyme activities of superoxide dismutase （SOD） in blood plasma and liver were analyzed 2 days after Enrofloxacin withdrawal in starlet （Acipenser ruthenus Linnaeus） and Amur sturgeon （Acipenser schrenckii Brandt） orally administrated for En- rofloxacin at a dose of 0, 20, 40, 60, 80 and 100mg/kg fish for 5 days to evaluate changes in SOD activities and mechanism of the drug metabolism in both sturgeon. There was SOD enzyme in both sturgeons at a different level and the SOD activities were found higher in the livers than those in the blood plasma no matter whether the drug was delivered or not. The SOD activities were found to be increased first and then decreased in the two tissues under the different drug delivery concentration, with the maximal value at the concentration of 40 mg/kg fish. In the blood plasma, hardly change in the SOD activities was observed through the period of drug delivery and there were higher SOD activities in the starlet than those in the Amur sturgeon. However, the SOD activities were fluctuated sharply through drug delivery in the liver, in which there significantly higher SOD activities in the Amur sturgeon than those in the starlet at a concentration of less than 40 mg/kg fish. It was the opposite case at a concentration of more than 40 mg/kg fish.

The changes in plankton species community, cells abundance, dominate species and seasonal variation in brood sturgeon culture ponds were studied from May to September in 2009. The results showed that the sediment resuspension caused by brood sturgeon＇s daily movements induced Secchi depth transparency stable at low levels. The Chlorophyta Selenastrum spp. and Chlorella spp. were found to be dominant in phytoplankton community. The abundance of phytoplankton were found to range from 1.0883 × 10^7ind./L to 1.5662x 10^7ind./L, and biomass range from 14.6438 mg/L to 19.2535 mg/L. The Rotifera and Copepoda were dominant in zooplankton community. The abundance of zooplankton was ranged from 162.0000ind./L to 560.0000 ind./L ,and biomass from 0.3795 mg/L to 1.5482 mg/L. The changes in plankton community structure were attributed to the daily movements of the brood sturgeon.

An investigation on the community structure of phytoplankton and environmental impact assessment was carried out in Harbin section of Songhua River in August,2008. The results showed that a total of 72 species 43 genera 7 phylums of phytoplankton were recorded, the community structure of which mainly belongs to Chlorophyta, Bacillariophyta and Cyanophyta. The dominant species are completely from Chlorophyta Cyanophyta and Cyclotella of Bacillariophyta.Based on the dominant species, abundance and biomass, pollution indicator community and physical-chemical indicators, the comprehensive assessment indicates that Harbin section of Songhua River was eutrophication in summer.The construction of Dadingzishan Navigation and Hydropower Project has been leading to raising the water level and reducing the flow rate in Harbin section of Songhua River, resulting the slow succession of phytoplankton community structure from blue and green algae to the diatom in this water in summer.And the water bloom will break out easily.

In situ hybridization molecular hybrid technology as a combination of the basic principle of molecular hybridization and immunohistochemical is provided with a high application value, especially digoxigenin marker, which is characterized by safety, convenient, time-saving, and superior to biotin markers and radioactive marker technology in sensitivity and quality control. In this paper, the basic principles of digoxigenin in situ hybridization was described, and the current applications of this technique in breeding and disease diagnose were discussed in aquatic animals.

In this paper, existing forms of arsenic in the seafood that are connected with food safety and seashells physiology and biochemistry was reviewed. The limit content of arsenic in seawater is no more than 0.03mg/kg based on the standards, while, inorganic arsenic in soft tissue of seashell is between 0.Smg/kg and lmg/kg. At present, two-compartment model was applied to describe the heavy metal harm on shells. The other models was changed or improve from two-compartment model. It is proposed to strengthen the hazards of heavy metals on the description ofAnadara uropygimelana. This work responds to international technical barriers to trade actively, and also expands the area of heavy metals in shellfish.

Salmons and trouts are fishes that are sensitive to the temperature and the environment, the impacts of climate change on salmons and trouts especially the increased temperature arouse the change of environment impact salmons and trouts is obvious.This paper reviews the scientific literatures about the impacts of climate changes on salmons and trouts, reviews the impacts of climate changes on aquatic organisms in terms of habitat environment,then reviews temperature, change in C02 concentration, change in precipitation and acid rainfall, the change in the increased UVB radiation and the disease of salmons and trouts. This paper finds some existed problems such as the research blank,zone limitations,lack of estimate model and give some advices about the future research.