Analysis on Growth and Development Laws of Different Mink Varieties

This study was conducted to investigate the growth and development laws of different mink varieties. The weights of six mink varieties were determined at different growth and development stages, respectively. The growth curves were drawn, and the differences in 150-day-old weight were analyzed. The results showed that the weight of each mink variety grew rapidly after weaning to adult weight; the weight of sliver blue mink was significantly higher than those of imported regal white mink and imported palomino mink; and there were no significant differences between other varieties.

Prokaryotic Expression and Preparation of Polyclonal Antibody of HtrA Protein from Escherichia coli Causing Pneumonia in Fox

To investigate the roles of HtrA protein in bacterial adaption to stresses, htra gene was cloned from an Escherichia coli strain isolated from silver fox, double digested, and ligated into the prokaryotic expression vector pET32a. Then, the recombinant plasmid pET32a-htra was transformed into E. coli BL21 competent cells. The over-expression of His-HtrA protein was induced by the addition of IPTG at a final concentration of 1 mmol/L, and verified by SDA-PAGE and Western blot. In addition, the protein was purified with Ni-NTA agarose, and used to immunize mice,and the polyclonal antibody specifically bound to E. coli HtrA protein. The results will provide a theoretical basis for studying the roles of HtrA protein and developing vaccines for fur-bearing animals against E. coli.

Developmental Changes of GHR Gene Expression in Multiple Tissues of Mink

[Objective] The paper was to explore the changes of GHR gene expression in different tissues of mink.[Method] With American mink as the research object, the expression volumes of GHR gene in heart, liver, spleen, lung, kidney, intestine and skin tissues at different growth stages(45, 90, 120, 150 and 180 days of age) were detected by real-time PCR, and comparative analysis was performed.[Result] The GHR gene expressions in heart, liver and spleen tissues at 180 days of age were extremely higher than those at other days of age( P<0.01). The GHR gene expression in lung tissue at 120 days of age was extremely higher than those at other days of age( P<0.01). The GHR gene expressions in intestine tissue at 45 and 120 days of age were extremely higher than those at other days of age(P<0.01), but no significant difference was observed between 45 and 120 days of age(P>0.05). The GHR gene expression in kidney tissue at 150 days of age was significantly higher than those at other days of age( P<0.05).The GHR gene expression in skin tissue was extremely higher than that those at other days of age( P<0.01). The GHR gene expressions in intestinal tissue at 45 and 120 days of age were extremely higher than those in other tissues(P<0.01). The GHR gene expressions in skin tissue at 90 days of age was extremely higher than those in other tissues(P<0.01). The GHR gene expressions in intestine, spleen and kidney tissues at 150 days of age were extremely higher than those in other tissues(P<0.01). The GHR gene expressions in spleen tissue at 180 days of age was extremely higher than those in other tissues(P<0.01).[Conclusion] The expression of GHR gene in mink showed obvious spatio-temporal specificity.

Effects of Raphani Semen on anti-fatigue and pharmacokinetics of Panax ginseng

Objective: To explain the phenomenon that Panax ginseng is not compatible with Raphani Semen based on pharmacodynamics and pharmacokinetics.Methods: The forced swimming time and biochemical parameters such as blood lactate(BLA), serum urea nitrogen(SUN), and hepatic glycogen(GLU) were determined for anti-fatigue experiment. The UPLCMS/MS was used to analyze the pharmacokinetics of Rg1, Re, Rb1, and Rd after orally administration of P. ginseng and P. ginseng combined with Raphani Semen to rats. Pharmacokinetic differences of four ginsenosides between single uses of P. ginseng and combined with Raphani Semen were investigated.Results: The results showed that Raphani Semen tended to significantly reduce the anti-fatigue activity of P. ginseng. Co-administration of P. ginseng and Raphani Semen had significant effects on the pharmacokinetics of the four ginsenosides in rats compared to that observed with P. ginseng extract alone. The AUC0–12 hvalues of the four ginsenosides in PG group were higher than the corresponding values in the PR group. It can be inferred that Raphani Semen decreased the blood exposure of the four ginsenosides in rats when it combined with P. ginseng.Conclusion: The anti-fatigue activity and pharmacokinetic results showed that Raphani Semen may reduce the pharmacological actions of P. ginseng.

Effects of dietary methionine supplementation on growth performance of cubs,nutrient digestibility, nitrogen metabolism and serum biochemical indicators of female blue foxes(Alopex lagopus)

The objective of the present study was to investigate the effects of methionine(Met) supplementation on growth performance of cubs, nutrient digestibility, nitrogen metabolism and serum biochemical parameters of female blue foxes. One hundred primiparous female blue foxes that were similar in breeding date, pedigree, age, and weight were selected for the trial. The foxes were randomly assigned to four groups(n = 25 each group) and fed diets supplemented with Met at 2(Met2), 4(Met4), 6(Met6)and 8 g/kg(Met8), respectively, for 40 days. Our data showed that body weights at 20 and 40 d were significantly higher in the Met4 group than in the Met2 group(P < 0.05). The Met4 group also had the highest apparent digestibility of dry matter and crude protein compared with either the Met2, Met6, or Met8 group(P< 0.05). The serum Met and isoleucine(Ile) concentrations were significantly higher in the Met4 group than in the Met6 or Met8 group(P < 0.05). In summary, these data indicate that supplementary Met improves growth performance of cubs likely due to increased crude protein and dry matter and increased nitrogen retention of female blue foxes. The optimal amount of Met supplementation is10 g/kg basal diet.

Mink Circovirus Can Infect Minks, Foxes and Raccoon Dogs

Dear Editor,Mink circovirus (MiCV), which is clustered in the genus Circovirus of the family Circoviridae, was first described in minks from farms in Dalian, China in 2013 (Lian et al.2014). The complete single-stranded circular genome of the virus is 1,753 nucleotides long and contains two major open reading frames (ORFs), designated ORF1 (Rep gene)and ORF2 (Cap gene)(Lian et al. 2014;Ge et al. 2018).

Single-cell transcriptome reveals core cell populations and androgen-RXFP2 axis involved in deer antler full regeneration

Deer antlers constitute a unique mammalian model for the study of both organ formation in postnatal life and annual full regeneration.Previous studies revealed that these events are achieved through the proliferation and differentiation of antlerogenic periosteum(AP)cells and pedicle periosteum(PP)cells,respectively.As the cells resident in the AP and the PP possess stem cell attributes,both antler generation and regeneration are stem cell-based processes.However,the cell composition of each tissue type and molecular events underlying antler development remain poorly characterized.Here,we took the approach of single-cell RNA sequencing(scRNA-Seq)and identified eight cell types(mainly THY1^(+)cells,progenitor cells,and osteochondroblasts)and three core subclusters of the THY1^(+)cells(SC2,SC3,and SC4).Endothelial and mural cells each are heterogeneous at transcriptional level.It was the proliferation of progenitor,mural,and endothelial cells in the activated antler-lineage-specific tissues that drove the rapid formation of the antler.We detected the differences in the initial differentiation process between antler generation and regeneration using pseudotime trajectory analysis.These may be due to the difference in the degree of stemness of the AP-THY1+and PP-THY1^(+)cells.We further found that androgen-RXFP2 axis may be involved in triggering initial antler full regeneration.Fully deciphering the cell composition for these antler tissue types will open up new avenues for elucidating the mechanism underlying antler full renewal in specific and regenerative medicine in general.