Longwu Geng

The Complete mitochondrial genome of Spinibarbus denticulatus (Oshima)

Abstract 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.

Mitochondrial DNA sequence of Mongolian redfin (Chanodichthys mongolicus).

Abstract 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.

Determining oxygen consumption rate and asphyxiation point in Chanodichthys mongolicus using an improved respirometer chamber

Knowledge of oxygen consumption rates and asphyxiation points in fish is important to determine appropriate stocking and water quality management in aquaculture. The oxygen consumption rate and asphyxiation point in Chanodichthys mongolicus were detected under laboratory conditions using an improved respirometer chamber. The results revealed that more accurate estimates can be obtained by adjusting the volume of the respirometer chamber, which may avoid system errors caused by either repeatedly adjusting fish density or selecting different equipment specifications. The oxygen consumption rate and asphyxiation point of C. mongolicus increased with increasing water temperature and decreasing fish size. Changes in the C. mongolicus oxygen consumption rate were divided into three stages at water temperatures of 11–33°C: (1) a low temperature oxygen consumption rate stage when water temperature was 11–19°C, (2) the optimum temperature oxygen consumption rate stage when water temperature was 19–23°C, and (3) a high temperature oxygen consumption rate stage when water temperature was > 27°C. The temperature quotients (Q10) obtained suggested that C. mongolicus preferred a temperature range of 19–23°C. At 19°C, C. mongolicus exhibited higher oxygen consumption rates during the day when the maximum values were observed at 10:00 and 14:00 than at night when the minimum occurred at 02:00.

Comparative study of the nutritional composition and toxic elements of farmed and wild Chanodichthys mongolicus

Information of the difference in quality between farmed and wild fish is central to better ensuring fish products produced in aquaculture meet regulatory and consumer requirements. Proximate composition, amino acid and fatty acid profiles, and toxic elements contents of farmed and wild Chanodichthys mongolicus were established and compared. Significantly higher crude protein content while lower moisture content in farmed fish compared to wild fish were observed (P<0.05). The percentages of total amino acids (TAA), total essential amino acids (TEAA), total non-essential amino acids (TNEAA) and total delicious amino acids (TDAA) in farmed fish were all significantly higher than those in the wild equivalent (P<0.05). Compared to the FAO/WHO recommended reference values, the ratios of TEAA/TAA (39.84%–40.33%) were comparable to 40% and TEAA / TNEAA (66.22%–67.60%) were above 60%. Fatty acid profiles in both farmed and wild C. mongolicus were dominated by monounsaturated fatty acid (MUFA), with farmed fish contained much more MUFA content compared to wild counterpart (P<0.05). Notably, wild fish exhibited significantly higher levels of total polyunsaturated fatty acid (PUFA) including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) than farmed fish (P<0.05). The EPA (C20:5n3) and linoleic acid (C18:2n6) were the predominant PUFA in wild and farmed C. mongolicus, respectively. Moreover, farmed fish displayed an overall lower toxic element levels (As, Cd, Pb and Hg) in comparison with wild fish, and both were far lower than the established limit standard. In conclusion, our results suggest that the nutritional quality of farmed C. mongolicus was inferior to their wild counterpart with respect to fatty acids nutrition, and therefore further studies should focus on the improving C. mongolicus diet in order to enhance the overall nutritional composition.

Mitochondrial DNA sequence of Culter compressocorpus

Abstract In this study, the complete mitochondrial genome of Culter compressocorpus was detected and annotated. The circular mtDNA molecule was 16,623 bp in length which contains 22 transfer RNA genes, 13 protein-coding genes, 2 ribosomal RNA genes, and the non-coding control region (D-loop). Its total protein-coding genes content is 68.67% in whole mitochondrial genome. The mitochondrial genome can contribute to the studies on geographical distribution and genetic diversity of C. compressocorpus resources, as well as molecular phylogeny and species identification in Cyprinidae.

Mitochondrial DNA sequence of Pseudorasbora parva (Cyprinidae: Gobioninae)

Abstract In this study, the complete mitochondrial genome of Pseudorasbora parva (Cyprinidae: Gobioninae) was determined. The circular mtDNA molecule was 16,601 bp in length which contains 22 transfer RNA genes, 13 protein-coding genes, 2 ribosomal RNA genes and non-coding control region (D-loop). The critical central conserved sequences were also detected. Its total A + T content is 55.97%. The mitochondrial genome can contribute to the studies on geographical distribution and genetic diversity of P. parva resources, as well as molecular phylogeny and species identification in Cyprinidae.

Effect of Salinity and Alkalinity on Luciobarbus capito Gill Na

We evaluated the individual and combined effects of salinity and alkalinity on gill Na+/K+-ATPase enzyme activity, plasma ion concentration, and osmotic pressure in Luciobarbus capito. Increasing salinity concentrations (5, 8, 11, and 14 g/L) were associated with an initial increase and then decrease in L. capito gill Na+/K+-ATPase activity. Activity was affected by the difference between internal and external Na+ ion concentrations and osmotic pressure (P < 0.05). Both plasma ion (Na+, K+, and Cl−) concentration and osmotic pressure increased significantly (P < 0.05). An increase in alkalinity (15, 30, 45, and 60 mM) caused a significant increase in plasma K+ and urea nitrogen concentrations (P < 0.05) but had no effect on either plasma osmotic pressure or gill filament ATPase activity. In the two-factor experiment, the saline-alkaline interaction caused a significant increase in plasma ion (Na+, Cl−, and urea nitrogen) and osmotic pressure (P < 0.05). Variance analysis revealed that salinity, alkalinity, and their interaction significantly affected osmotic pressure, with salinity being most affected, followed by alkalinity, and their interaction. Gill filament ATPase activity increased at first and then decreased; peak values were observed in the orthogonal experiment group at a salinity of 8 g/L and alkalinity of 30 mM.

The complete mitochondrial genome of Alburnus chalcoides aralensis

Abstract The complete mitochondrial genome of Alburnus chalcoides aralensis is 16,604 bp in length and includes 13 protein-coding genes, 2 ribosomal genes, 22 transfer RNA genes and 2 non-coding sequences. The major non-coding sequence (D-loop control region) contains five conserved sequence blocks (CSB-1, CSB-2, CSB-3, CSB-D and CSB-F) and one termination associated sequence. The other non-coding sequence is the origin of light-strand replication, which has the potential to fold into a stable stem-loop secondary structure. The mitochondrial genomic sequence will help us study the conservation genetics and evolution of Cyprinidae.