The gene of stearoyl-CoA Desaturase(SCD) as a rate limiting enzyme involved in desaturation of saturated fatty acids plays vital roles in maintaining membrane fluidity and is considered as a key candidate which helps to improve cold tolerance.A SCD cDNA from common carp(Cyprinus carpio)(CcSCD) brain at cooling temperature was characterized and the transcription expression profiles were examined in the common carp exposed to cold(6℃) and warm(23℃) temperatures using real time RT-PCR.A full-length CcSCD cDNA was shown to be comprised of 2618 bp,including an open reading-frame of 975 bp and deduced 324 amino acid residues.Phylogenetic analysis revealed that the SCD protein sequences of the common carp and grass carp(Ctenopharyngodon idella) were clustered together,sharing the highest level of similarity(88%).The quantified results showed that under cooling temperature,CcSCD transcripts were significantly up-regulated(P〈0.01),in comparison to transcripts of samples from normal temperature.The findings help to establish a transgene construction and to apply genetic manipulation to identify functions of CcSCD gene of fish during cold response in future.

The polymorphic primers for Dolly Varden Salvelinus malma as a rare and endangered cold-water species in China was screened from char S.confluentus by microsatellite,and the genetic diversity of the Yalu River population was analyzed.The results showed that 5 microsatellite primers screened from 10 microsatellite primers in Salvelinus malma were polymorphous in Dolly Varden.There were the number of alleles(Na) of 6~22(average 15),heteroerozygosity(H) of 0.4063~0.9333(average 0.7851) and polymorphic information content(PIC) of 0.716 4~0.919 8(average 0.8536) in Yalu River population of Dolly Varden.The findings indicated that the 5 primers from S.confluentus provided a good versatility in dolly varden,and a high level of genetic diversity in Yalu River population,which provides a genetics theoretical basis for the protection and management of germoplasm resources of Dolly Varden in China.

The eggs of Fangzheng silver crucian carp(Carassius auratus auratus) as gynogenetic crucian carp were activated by homogenous and by heterogeneous(common carp Cyprinus carpio and topmouth gudgeon Pseudoroashora parva) sperm,forming three offsprings Fangzheng silver crucian carp ♀× Fangzheng silver crucian carp♂(FF),Fangzheng silver crucian carp ♀× common carp ♂(FH) and Fangzheng silver crucian carp♀× topmouth gudgeon♂(FM).The fry of the three offsprings were reared in net cages disposed in a pond,and the survival,growth and sexual ratio were compared.The survival of FF((91.15±1.78)%) fry was shown to be very significantly higher than that in FM(87.50±2.13%)and FH(85.00±1.04%)(P〈0.01).The juveniles in FM(20.17±4.33 g) and FH(23.13±3.58 g) had significantly higher final body weight than that in FF(18.90±3.82 g)(P〈0.05).There were very significantly higher female proportion in the offsprings(99% in FM,73% in FF and 99% in FH)(P〈0.01).The results approved the biological effects of heterogametes and will be useful for the utilization of heterogametes.

In this study,992 microsatellite markers were selected to analyze the genomic DNA of 190 individuals derived from the sibling group of F1 hybrids mirror carp(Cyprinus carpio L.) The map was found to span 5138.2 cM over 51 linkage groups,with an average spacing of 5.19 cM.Then quantitative trait loci(QTLs) associated with Acid phosphatase(ACP) were identified by the interval mapping of the software MapQTL 6.0.Nine QTLs were identified for ACP on eight linkage groups.Among the nine QTLs controlling ACP in mirror carp,the maximum LOD score was found to be 5.37(LG24) in which 13.8% of the phenotypic variations were explained.By BLAST with the zebrafish for sequence alignment,molecular markers were found homologous with leucine-rich repeat-containing protein,transmembrane protein 50A,ADP-ribosylation factor and cytokine receptor family member b8 in zebrafish.The findings could be well used for molecular marker assisted selection and for disease control in mirror carp.

In this study,magnetic beads enriched method was used to isolate microsatellite DNA from Aspiorhynchus laticeps Day genome and 13 sites were found.One thousand pairs of primers from common carp Cyprinus carpio randomly were chosen to test for the cross-species amplification in Aspiorhynchus laticeps Day,and 18 primers were amplified successfully.Polymorphism of all these 31 distinct loci was assessed using 24 Aspiorhynchus laticeps Day individuals and 19 Schizthorax biddulphi Gvnther,and a total of 110 alleles were detected.The Aspiorhynchus laticeps Day was shown to have average PIC of 0.5353,Ho of 0.5306,and He of 0.6057,indicating that the polymorphism of Aspiorhynchus laticeps groups is high and the genetic diversity is in the mid to upper level.The Aspiorhynchus laticeps Day and Schizthorax biddulphi Gvnther were found to show genetic distance of 0.6211 and genetic similarity coefficient of 0.4763,indicating that the two groups is of different genera in the same family.

The comparative morphological characteristics of teeth,tongue,gill rakers,stomach,pyloric caeca,liver,pancreas,and gallbladder were described in adult taimen(Hucho taimen) and chum salmon(Oncorhynchus keta).The body length,head length,snout length,mouth breadth,mouth length,and the lengths of esophagus,stomach,intestine and digestive tract were measured and some relevant ratios were calculated in both taimen and chum salmon.The results showed that the taimen and chum salmon had typical digestive tract characteristics of the carnivorous fish including big mouth,a ratio of oropharyngeal length to head length=0.62~0.71,and short intestine with intestinal length / body length =0.69.The clear mucosal folds were observed in the inner process of esophagus,stomach and intestinal walls.A separate and developed liver and pancreas was found and the relationships between section of the digestive tract,the feeding habits and morphological characteristics of the digestive system were discussed.

A survey was conducted to investigate the community structure and biodiversity of macrozoobenthos in the Hailang River during August in 2011.A total of 56 species of macrobenthos were collected,belonging to 14 orders and 31 families,among which aquatic insects were the predominant,with 43 species(75.44% of the total) belonging to 21 families and 7 orders.A total of 51 species of macrobenthos were found in Endemic Fish Natural Aquatic Germplasm Resource Reserve Zone in Hailang River,belonging to 13 orders and 30 families,among which Ephemerida,Trichoptera and Diptera were prevalent groups in the number of community.The macrobenthos were found at annual average density of 180.19 ind·m-2 and biomass of 3.20 g·m-2.The maximum was found to be the predators with 25 species in all functional feeding groups,followed by 15 collectors,10 scrapers and 6 shredders.The prevalent macrobenthos species were of Brachycentinao,Setodes,Siga substraiata,Epeorus uenoi and Stenpsyche griseipennis in present Hailang River.The water quality was assessed to be basically similar and to be clear in endemic fish Natural Aquatic Germplasm Resource Reserve Zone in Hailang River by Shannon-Weiner index,biotic index(BI) and Simpson index,with coincident change tendency of apinoid grade.

Variations of phytoplankton community structure in Dangbi Town of Xingkai Lake was investigated in July 2009.The results showed that the phytoplankton assemblage was composed of 41 species in total,belonging to seven taxonomic groups.Chlorophyta were represented by the highest percentage of taxa(39.0%) followed by Bacillariophyta(24.4%).The average cell density of phytoplankton was 192.97×104ind·L-1 and the average biomass was 2.4605mg·L-1.Bacillariophyta were represented by the highest cell density(147.47×104ind·L-1) and biomass(2.2818mg·L-1).Dominant species concluded Bacillariophyta,Chlorophyta,Cyanophyta,Xanthophyta.Dominant species were Cyclotella comta,Melosira granulate,Chlorella vulgaris,Ocystis lacustris,Chroococcus minor and Tribonemn sp...The diversity of phytoplankton in that lake was abundant(the value of H’ was 2.09;the value of J was 0.56).Over time,there was little change in dominant species and large change in species composition,cell density and biomass.The later time was the lower X index was.Compared with data between 2001 and 2009,species composition and cell density of phytoplankton in Xingkai Lake declined slightly.Dominant species of Bacillariophyta and Cryptophyta declined and dominant species of Chlorophyta increased.The percentage of filamentous algae in dominant species was increasing.In addition,the biomass of phytoplankton rose in Xingkai Lake.At the same time,fish production potential tended to increase in Dangbi Town of Xingkai Lake.There were two purposes of this study.One purpose was to accumulate basic data of phytoplankton resources in Dangbi Town of Xingkai Lake.The other purpose was to provide reference data for fish feeding habits that was studied by co-workers in Xingkai Lake.

Effects of three Chinese medicinal herb complex additives(Cyrtomium fortunei,prescription I and prescription II) aqueous extract on the contents of active material and the activities of enzymes related to antioxidation in 1+ age old Amur sturgeon(Acipenser schrencki Brandt) by oral perfusion.The Amur sturgeon juveniles with body weight of 0.08±0.10 kg were cultured in aquaria of each 0.90 m×0.50 m×0.45 m at water temperature of 22℃ for 2 weeks and then were orally administrated by Cyrtomium fortunei,prescription I and prescription II at a dose of 9,17.5 and 36 g·50 kg-1 body weight once a day for 14 days,respectively,oral distilled water as the control.After 14 day administration,some test fish were stimulated for two hours at high temperature(30℃),and then all sampled together to analyze the activities of superoxide dismutase(SOD),nitric oxide synthase(NOS) and the contents of malonaldehyde(MDA) and nitric oxide(NO).The three prescriptions were shown to play a certain role in improvement of antioxidation in Amur sturgeon.Cyrtomium fortune additive led to increase in activity of SOD in several tissues of Amur sturgeon and to promote a rapid response of fish under the thermal stimulation.Although Cyrtomium fortune showed decrease in the content of MDA,it had a certain influence on liver antioxidation.Therefore it should be administered properly and the optimum administration modalities were required.The decrease in content of MDA was observed in the body of the fish administrated by Prescription I and improvement of a rapid response of the fish administrated by Prescription I to the thermal stimulation.Prescription II had a better performance in antioxidation,but did not show any effects on high temperature stimulation.

Larval sea cucumber(Apostichopus japonicus) was cultured in six 30-L plastic tanks at a rate of 303 individuals /L and fed algal mixture of Dunaliella salina and Chaetoceros müelleri for 10 days at water temperature of 21℃~22 ℃.The various 10 cm×10 cm settlements including rugged polyethylene planks,flat polyethylene planks,and with 500 um or 250 nm groove surfaces and different colors(green,black,yellow,red,and blue) were positioned in the tanks just before doliolaria stage to evaluate the effects of settlement types,roughness and surface color on attachment of larval sea cucumber.It was found that there were 68.76% more sea cucumber larvae on the rugged polyethylene planks than that on the flat polyethylene planks,very significantly different from the flat polyethylene planks(t=7.131〉2.804,df=23).The attachment of the larvae was showed to increase with increase in the roughness on the settlements,and the amount of larvae on the smooth polyethylene planks was found to be 267.42% higher than that on the planks with 500 um groove surfaces(with significant difference) and 32.34% higher than that on the plankes with 250 nm groove surfaces(without significant difference).There were more sea cucumber larvae on the red and black planks than that in the control groups(without color),84.52% higher on the red plates and 37.49% on the black plates(with very significant difference).Significant reduction in the larvae number was observed on the day 5 after the attachment of the larvae which had only one tube foot,even though the attachment was found increase as the larval culture proceeded.The results were discussed in detail from attachment mechanism including environment,tube foot development of the larvae and functions of a settlement.

Design of an oxygen consumption test device for fish is described,and the oxygen consumption and asphyxia point were practically determined in juvenile paddlefish with body weight of(156±3.36)g.In the design of the device,the structural variables were found to ensure the even water flowing in a respiratory chamber,and sampling accuracy without air bubble interference,and to observe the fish behavior conveniently with accuracy data during determination of the fish oxygen consumption,and suffocation point.By the oxygen consumption test device,the paddlefish juveniles were showed to have the maximum oxygen consumption of(0.528 + 0.035) mg·g-1·h-1,the minimum oxygen consumption of(0.197 + 0.028) mg·g-1·h-1,and asphyxia point of 3.468mg·L-1 dissolved oxygen.

Cold water Salmonids as a global culture fish are characterized by high quality flesh,high protein and unsaturated fat acids contents,no intermuscular bones,and easy to be processed,and particularly,Atlantic salmon(Salmo salar),rainbow trout(Oncorhynchus mykiss) and charrs are the important object of aquatic breeding and genetics research.The past and current research status of the genetics and breeding of salmonid species are briefly described,and the advances in genetic parameters estimation of economic traits,selective breeding,molecular genetics and marker assisted breeding in salmonid species are introduced in this paper.Some suggestions are made for future directions and priorities of genetics and breeding of salmonid species to provide new ideas for the study and researchers in the field of aquatic breeding and genetics.

This study is based on industry information research on current industry situation,development trend in domestic and international.According to the result of industry information research,we gave some suggestions about the industry development of cold water fish in China.