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Three experiments including starvation and re-feeding, starvation and re-feeding recovery, and feeding frequency per day were conducted to approach the optimal feeding strategy for the growth and survival of juvenile Hucho taimen. In the experiment of starvation and re-feeding, all groups of restricted feeding showed non-compensatory growth. However, in the experiment of starvation and re-feeding recovery, different degrees of compensatory growth appeared in different starving groups, among which, the half a day starvation and half a day feeding group (S1/2) had a weight increment approximately the same as the control, and showed completely compensatory growth, indicating that the S1/2 could be a useful feeding strategy for the juvenile H. taimen at its early growth stage with the body mass from 0 to 2 g and at the water temperature from 9 to 15. 3°C. In feeding frequency experiment, the group T3 (three meals per day) had the highest body length, body mass, specific growth rate, and relatively high food conversion ratio, indicating that three meals a day could be more effective for improving the growth performance of juvenile H. taimen at its late stage with the body mass from 2 to 21 g and at the water temperature from 8. 8 to 15.5 °C. [ABSTRACT FROM AUTHOR]

This paper studied the effects of delaying first breeding Hucho taimen larvae for different days on the larvae growth, survival, and body size. Five treatments were installed, i. e., feeding begins on the first eating day (control, S0) and on the 9th, 12th, 15th, and 18th days after the first eating day (S1 -S4) at 10. 4-14. 9 °C, respectively. By the end of the experiment (36-day), the growth rate and initial feeding rate in S1 was higher than that in S0, and the overall mortality rate in S1 was lower, but the body size and mass in S1 and S0 had no significant difference. Compared with S0, S2 had higher growth rate, initial feeding rate, total mortality, and self-mutilation mortality, the body mass was significantly lower, but the body size had less difference. S3 had higher first feeding rate, body size, total mortality, and self-mutilation mortality, but significantly lower body mass than S0, whereas the growth rate had less difference. In S4, the growth rate and body mass were lower, and the total mortality and self-mutilation mortality were higher than those in S0. It was suggested that under the same conditions, delaying first feeding for 9 days would induce H. taimen larvae presenting "completely compensatory growth", and this feeding way could be applied for the culture of H. taimen larvae in their initial feeding period. [ABSTRACT FROM AUTHOR]

The article discusses a study that developed 12 polymorphic expressed sequence tag-simple sequence repeat (EST-SSR) markers from cDNA library by magnetic beads to analyze genetic diversity of breeding Hucho taimen (Pallas) in China. It examines the characteristics of EST-SSRs developed for the indigenous and endangered cold-water fish. Their genetic parameters were analyzed by EST-SSR. The study characterized 200 EST sequences and 12 polymorphic EST-SSR markers.

Monglian redfin is a kind of freshwater aquaculture species which has an important economic value in China. In this study, we report the complete sequence of mitochondrial genome of Monglian redfin. The complete mitochondrial genome sequence is determined to be 16,621 base pairs (bp) in length and contain 13 protein-coding gene (PCGs), 22 transfer RNA genes, large ( rrnL) and small ( rrnS) ribosomal RNA, and the non-coding control region. Its total A + T content is 55.98%. We also analyzed the structure of control region, six conserved sequence blocks (CSBs) (CSB-1, CSB-2, CSB-3, CSB-D, CSB-E and CSB-F) and one potential termination-associated sequence were detected and the control region also included a 2-bp tandem repeat with eight repeat times. [ABSTRACT FROM AUTHOR]

The article discusses a study analyzing the karyotypes of male and female endangered cold-water fish Hucho taimen (Pallas) at metaphase. The karyotype of Hucho taimen was shown to be 2n=84, and the results showed no chromosomal differences between the analyzed karyotypes. The article also highlights that the results may provide insights into chromosomal manipulations to facilitate the culture of the endangered fish.

The complete sequence of the mitochondrial genome of the white-spotted char (Salvelinus leucomaenis) was determined to be 16,658 bp in length, which contains the control region (CR), the origin of light-strand replication (OL), 22 transfer RNA genes, 2 ribosomal genes and 13 protein-coding genes. Overall, base composition of the complete mitochondrial DNA was 28.20% A, 26.51% T, 28.39% C, 16.90% G, with 54.71% AT. [ABSTRACT FROM PUBLISHER]

Spinibarbus denticulatus (Oshima) is a rare and commercial fish. The complete mitochondrial genome sequence of S. denticulatus will help us to study the genetic of conversation, such as the genetic diversity and genetic structure, and provides the basis for the study in evolution. In this paper, the complete mitochondrial genome of S. denticulatus was determined to be 16,549 bp in length by Sanger sequencing technology. Thirteen protein-coding genes, 22 tRNA genes and 2 ribosomal genes were characterized. We also analyzed the structure of control region, 6 CSBs (CSB-1, CSB-2, CSB-3, CSB-D, CSB-E and CSB-F) and 1 TAS were identified, the control region also included an AT unit tandem repeat with 17 repeat times. [ABSTRACT FROM AUTHOR]

Infectious hematopoietic necrosis virus (IHNV) is a significant rhabdoviral pathogen of salmonid fish. In this study, a single chain variable fragment (scFv) antibody library derived from rainbow trout ( Oncorhynchus mykiss ) and a glycoprotein fragment (named G4, 540 nt, 180 aa) of IHNV-Sn1203 isolate were co-expressed by a bacterial display technology. The library was subjected to three rounds of screening by flow cytometry (FCM) to select IHNV specific antibodies. Seven antibody clones with different mean fluorescence intensities (MFI) were obtained by picking colonies at random. The antibody clone with the highest MFI was expressed and purified. The purified IHNV-specific scFv antibody was used successfully in Western blotting, enzyme linked immunosorbent assay and an immunofluorescence antibody test. This method provides a high throughput means to screen an antibody library by flow cytometry and isolate an antibody that can be used as a potential universal reagent for the detection and confirmation IHNV strains that are prevalent throughout China. Statement of relevance Outbreaks of infectious hematopoietic necrosis caused severe economic losses to salmon and trout aquaculture in China every year. In this study, a panel of recombinant antibodies against Chinese IHNV isolates was obtained. The isolated antibody was proven can be used as a universal diagnosis regent for IHNV prevalent in China. The study provides a novel method for rapid development of antibodies to emerging diseases. [ABSTRACT FROM AUTHOR]

Three experiments including starvation and re-feeding, starvation and re-feeding recovery, and feeding frequency per day were conducted to approach the optimal feeding strategy for the growth and survival of juvenile Hucho taimen. In the experiment of starvation and re-feeding, all groups of restricted feeding showed non-compensatory growth. However, in the experiment of starvation and re-feeding recovery, different degrees of compensatory growth appeared in different starving groups, among which, the half a day starvation and half a day feeding group (S1/2) had a weight increment approximately the same as the control, and showed completely compensatory growth, indicating that the S1/2 could be a useful feeding strategy for the juvenile H. taimen at its early growth stage with the body mass from 0 to 2 g and at the water temperature from 9 to 15.3 degrees C. In feeding frequency experiment, the group T3 (three meals per day) had the highest body length, body mass, specific growth rate, and relatively high food conversion ratio, indicating that three meals a day could be more effective for improving the growth performance of juvenile H. taimen at its late stage with the body mass from 2 to 21 g and at the water temperature from 8.8 to 15.5 degrees C.

In order to detect Infectious hematopoietic necrosis virus with immunological methods, the surface glycoprotein of a recent IHNV-Sn isolated from farmed rainbow trout ( Oncorhynchus mykiss ) in China was amplified and cloned into pET27b(+) vector (designated as pET27b-G ). The expression of recombinant plasmid pET27b-G in E. coli BL21(DE3) was induced and determined by SDS-PAGE analysis. The predicted molecular weight of glycoprotein protein was approximately 55 kD and was confirmed in this study. The inclusion body of glycoprotein was treated with urea at different urea concentrations, and dialyzed into PBS buffer. Purified glycoprotein with high concentration was obtained after dialyzed in the PBS buffer. Antisera against glycoprotein were produced from immunized rabbits. The prepared antisera could react specifically with both the recombinant glycoprotein and natural glycoprotein of the IHNV-Sn isolated in the test of indirect ELISA, and the titer against the recombinant glycoprotein was 1:20,000. IFA showed that the antisera can recognize the glycoprotein located on the surface of IHNV-Sn and IHNV reference strain. These results indicated that the expressed glycoprotein was immunogenical and antigenical and could be functional as the natural IHNV glycoprotein. These results established a foundation for further study on vaccine and rapid diagnosis of IHNV.

This paper studied the effects of delaying first breeding Hucho taimen larvae for different days on the larvae growth, survival, and body size. Five treatments were installed, i. e. , feeding begins on the first eating day (control, S0) and on the 9th, 12th, 15th, and 18th days after the first eating day (S1 -S4) at 10.4-14.9 degree C, respectively. By the end of the experiment (36-day), the growth rate and initial feeding rate in S1 was higher than that in S0, and the overall mortality rate in S1 was lower, but the body size and mass in S1and S0 had no significant difference. Compared with S0, S2 had higher growth rate, initial feeding rate, total mortality, and self-mutilation mortality, the body mass was significantly lower, but the body size had less difference. S3 had higher first feeding rate, body size, total mortality, and self-mutilation mortality, but significantly lower body mass than S0, whereas the growth rate had less difference. In S4, the growth rate and body mass were lower, and the total mortality and self-mutilation mortality were higher than those in S0. It was suggested that under the same conditions, delaying first feeding for 9 days would induce H. taimen larvae presenting "completely compensatory growth", and this feeding way could be applied for the culture of H. taimen larvae in their initial feeding period.

Taimen (Hucho taimen) is a native fish species in China and it is in the state of endangerment. To explain clearly the genetic diversity and genetic structure, 9 wild populations of taimen were investigated using 20 microsatellite markers. The results showed that their observed heterozygosity ranged from 0.0994 to 0.8882, the expected heterozygosity varied from 0.2005 to 0.8759, and the range of PIC index was from 0.3432 to 0.5261 while population from Huma River had low genetic diversity. Fst of matching group ranged from 0.0246 to 0.2333 (P <0.0001)and Nm varied among 0.8216 to 9.9292, which indicated that the genetic differentiation was remarkable among populations.The half/full-sib family tests detected a proportion of half/full-sib family groups varying among 27.78% to 90.91%, showing a high inbred pressure and a risk of bottlenecks experienced by most groups. The AMOVA results showed that the global Fst was 0.1081; the clustering result showed that individuals from Beiji tributary of Heilongjiang River clustered as one clade, all individuals from Huma River and Wusuli River clustered as one clade and all individuals from the upper reaches of the Heilongjiang River clustered as another clade. All these results indicated that the decrease of taimen resource has affected the gene exchange among their populations. In order to achieve full protection of taimen germplasm resources, we should put an end to the destructive fishing for taimen and promotegene exchange among their populations.

Using seven pairs of microsatellite markers we studied the relationship between the size of the the candidate groups and the microsatellite paternity testing accuracy by separate breed or the microsatellite paternity appraisal ability by mixed breed. By computer software analysis, the appraisal ability decreased with the candidate groups increase. For the 81 putative parents the microsatellite paternity testing accuracy was 80% and the microsatellite paternity appraisal ability was 78.9%; for the 9 putative parents, the testing accuracy was 93.3% and the appraisal ability was 92.2%. The results indicated that the microsatellite DNA markers can be used for the parentage determination of Hucho taimen Pallas.