Experimental cloning of embryos through human-rabbit inter-species nuclear transfer

Therapeutic cloning,which is based on human somatic cell nuclear transfer,is one of our major research objectives.Though inter-species nuclear transfer has been introduced to construct human somatic cell cloned embryos,the effects of type,passage,and preparation method of donor cells on embryo development remain unclear.In our experiment,cloned embryos were reconstructed with different passage and preparation methods of ossocartilaginous cell,skin fibroblast,and cumulus cells.The cumulus cell embryos showed significantly higher development rates than the other two(P<0.05).The development rate of embryos reconstruct-ed with skin fibroblasts of different passage number and somatic cells of different chilling durations showed no significant difference.Also,fluorescence in situ hybridization(FISH)was conducted to detect nuclear derivation of the embryos.The result showed that the nuclei of the inter-species cloned embryo cells came from human.We conclude that(1)cloned embryos can be constructed through human-rabbit interspecies nuclear transfer;(2)different kinds of somatic cells result in different efficiency of nuclear transfer,while in vitro passage of the donor does not influence embryo development;(3)refrigeration is a convenient and efficient donor cell preparation method.Finally,it is feasible to detect DNA genotype through FISH.

Effects of foraging site distances on the intestinal bacterial community compositions of the sympatric wintering Hooded Crane(Grus monacha)and Domestic Duck(Anas platyrhynchos domesticus)

Background:The composition of intestinal microflora in animals is affected by cross-species transmission.In a nature reserve,the foraging sites of waterbirds are relatively fixed,but frequently close to residential areas and can also be visited by domestic fowls.It is easy to result in the trans-species-flock dispersal of gut microbes between the wild birds and domestic fowls.The effects of the variable foraging site distances on the gut microbe structures of the waterbirds and the sympatric domestic fowls are currently unclear,and further research is required to evaluate the impacts of geographic location on cross-infection.Methods:Illumina high-throughput sequencing and bioinformatics analysis software were utilized to compare and analyze the composition of gut microbes from the fecal samples of Hooded Cranes(HC;Grus monacha)and two groups of Domestic Ducks(Anas platyrhynchos domesticus)that foraged at 1 km(ducks in near areas,D-N),and 4 km(ducks in far areas,D-F)away from the habitats of the Hooded Cranes at Shengjin Lake,China.Results:The results showed that there were significant differences in the alpha-diversity of the gut bacteria in the HC,D-N,and D-F samples under the interspecific distance factor.The dominant bacterial phyla,Cyanobacteria and Proteobacteria,showed correlations with distance for each host.The D-N group had more diverse intestinal flora than the D-F,as they were physically closer to the HC and had more indirect contact and cross-transmission of their gut microbes.More potentially pathogenic bacterial sequences,and Operational Taxonomic Units(OTUs)were found in the D-N than in HC and D-F.Conclusions:Hooded Cranes and the Domestic Duck populations at variable distances from the cranes showed significant differences in their intestinal bacteria and potentially pathogenic bacteria.The closer the foraging sites were,the easier the intestinal flora spread across species.The results provide a basis for determining the safe distance between wild birds and domestic fowls in a nature reserve.

Porcine circovirus type 2(PCV2)and Campylobacter infection induce diarrhea in piglets:Microbial dysbiosis and intestinal disorder

Diarrhea is considered to be associated with microbial dysbiosis caused by infection of pathogens but poorly understood.We herein characterized the colonic microbiota of diarrheal early-weaning piglets infected with porcine circovirus type 2(PCV2)and Campylobacter.Campylobacter infection significantly decreased species richness and Shannon diversity index of colonic microbiota together with a significant increase in the proportion of Campylobacter and Enterobacteriaceae,whereas no significant difference on the above indexes was observed in piglets infected with PCV2 compared with healthy piglets,PCV2 and Campylobacter infection could disturb the homeostasis of colonic microbiota through deterioration of ecological network within microbial community,and specially Campylobacter performed as a module hub in ecological networks.The microbial dysbiosis caused metabolic dysfunction and led to a remarkable reduction in production of short chain fatty acids,following by a higher pH level in colon cavity.Campylobacter infection disturbed the function of colonic tract barrier observed in terms of significant lower relative expression of claudin-1,occluding,and zonula occludens protein-1 genes,and PCV2 infection induced intestinal inflammation together with a higher permeability of colon.Generally,these results suggested that PCV2 and Campylobacter infection could induce microbial dysbiosis and metabolic dysfunction,and cause intestinal disorder,all of which finally were associated to contribute to the diarrhea of early-weaning piglets.