Current study adopted gene flow theory and selection index method to compare the breeding efficiency of three breeding plans in the Chinese Holstein cattle using ZPLAN software. Simulated conventional progeny-testing ...Current study adopted gene flow theory and selection index method to compare the breeding efficiency of three breeding plans in the Chinese Holstein cattle using ZPLAN software. Simulated conventional progeny-testing program (PT) and young sire program (YS) were compared with breeding program using genomic selection (GS) taking parameters derived from Chinese Holstein breeding system. The results showed that, GS shortened generation interval by 1.5-2.2 years, and increased the genetic progress by 30-50%, comparing to PT and YS, respectively. Economic analysis showed that GS could obtain a higher breeding efficiency, being 119 and 97% higher than that of PT and YS, respectively; and GS was also powerful in improving functional traits with a low heritability. Main factors affecting breeding efficiency in GS were further discussed, including selection intensity, accuracy and the cost of SNP genotyping. Our finding provided references for future designing and implementing GS in Chinese dairy population.展开更多
Advances in molecular biotechnology have introduced new generations of molecular markers for use in the genetic improvement of farm animals. Consequently, more accurate genetic information can be obtained to better un...Advances in molecular biotechnology have introduced new generations of molecular markers for use in the genetic improvement of farm animals. Consequently, more accurate genetic information can be obtained to better understand existing animal genetic resources. This review gives a brief summary on the development of genetic markers including both the classical genetic markers and more advanced DNA-based molecular markers. This review will help us better understand the characteristics of different genetic markers and the genetic diversity of animal genetic resources.展开更多
Meat and milk production needs to increase ～ 70–80% relative to its current levels for satisfying the human needs in 2050.However,it is impossible to achieve such genetic gain by conventional animal breeding systems...Meat and milk production needs to increase ～ 70–80% relative to its current levels for satisfying the human needs in 2050.However,it is impossible to achieve such genetic gain by conventional animal breeding systems.Based on recent advances with regard to in vitro induction of germ cell from pluripotent stem cells,herein we propose a novel embryo-stem cell breeding system.Distinct from the conventional breeding system in farm animals that involves selecting and mating individuals,the novel breeding system completes breeding cycles from parental to offspring embryos directly by selecting and mating embryos in a dish.In comparison to the conventional dairy breeding scheme,this system can rapidly achieve 30–40 times more genetic gain by significantly shortening generation interval and enhancing selection intensity.However,several major obstacles must be overcome before we can fully use this system in livestock breeding,which include derivation and mantaince of pluripotent stem cells in domestic animals,as well as in vitro induction of primordial germ cells,and subsequent haploid gametes.Thus,we also discuss the potential efforts needed in solving the obstacles for application this novel system,and elaborate on their groundbreaking potential in livestock breeding.This novel system would provide a revolutionary animal breeding system by offering an unprecedented opportunity for meeting the fast-growing meat and milk demand of humans.展开更多
Background Hepatic steatosis is a prevalent manifestation of fatty liver, that has detrimental effect on the health and productivity of laying hens, resulting in economic losses to the poultry industry. Here, we aimed...Background Hepatic steatosis is a prevalent manifestation of fatty liver, that has detrimental effect on the health and productivity of laying hens, resulting in economic losses to the poultry industry. Here, we aimed to systematically investigate the genetic regulatory mechanisms of hepatic steatosis in laying hens.Methods Ninety individuals with the most prominent characteristics were selected from 686 laying hens according to the accumulation of lipid droplets in the liver, and were graded into three groups, including the control, mild hepatic steatosis and severe hepatic steatosis groups. A combination of transcriptome, proteome, acetylome and lipidome analyses, along with bioinformatics analysis were used to screen the key biological processes, modifications and lipids associated with hepatic steatosis.Results The rationality of the hepatic steatosis grouping was verified through liver biochemical assays and RNA-seq. Hepatic steatosis was characterized by increased lipid deposition and multiple metabolic abnormalities. Integration of proteome and acetylome revealed that differentially expressed proteins(DEPs) interacted with differentially acetylated proteins(DAPs) and were involved in maintaining the metabolic balance in the liver. Acetylation alterations mainly occurred in the progression from mild to severe hepatic steatosis, i.e., the enzymes in the fatty acid oxidation and bile acid synthesis pathways were significantly less acetylated in severe hepatic steatosis group than that in mild group(P < 0.05). Lipidomics detected a variety of sphingolipids(SPs) and glycerophospholipids(GPs) were negatively correlated with hepatic steatosis(r ≤-0.5, P < 0.05). Furthermore, the severity of hepatic steatosis was associated with a decrease in cholesterol and bile acid synthesis and an increase in exogenous cholesterol transport.Conclusions In addition to acquiring a global and thorough picture of hepatic steatosis in laying hens, we were able to reveal the role of acetylation in hepatic steatosis and depict the changes in hepatic cholesterol metabolism. The findings provides a wealth of information to facilitate a deeper understanding of the pathophysiology of fatty liver and contributes to the development of therapeutic strategies.展开更多
Background Baicalin and probiotic cocktails are promising feed additives with broad application prospects.While probiotic cocktails are known to enhance intestinal health,the potential synergistic impact of combining ...Background Baicalin and probiotic cocktails are promising feed additives with broad application prospects.While probiotic cocktails are known to enhance intestinal health,the potential synergistic impact of combining baicalin with probiotic cocktails on the gut health of broiler chickens remains largely unexplored.Therefore,this study aims to investigate the influence of the combined administration of baicalin and probiotic cocktails on the composition of ileal and cecal microbiota in broiler chickens to elucidate the underlying mechanisms responsible for the healthpromoting effects.Results A total of 3201-day-old male Arbor Acres broilers were divided into 4 groups,each with 8 replicates of 10 chicks per replicate.Over a period of 42 d,the birds were fed a basal diet or the same diet supplemented with 37.5 g/t baicalin(BC),1,000 g/t probiotic cocktails(PC),or a combination of both BC(37.5 g/t)and PC(1,000 g/t).The results demonstrated that BC+PC exhibited positive synergistic effects,enhancing intestinal morphology,immune function,and barrier function.This was evidenced by increased VH/CD ratio,sIgA levels,and upregulated expression of occludin and claudin-1(P<0.05).16S rRNA analysis indicated that PC potentiated the effects of BC,particularly in the ileum,where BC+PC significantly increased theα-diversity of the ileal microbiota,altered itsβ-diversity,and increased the relative abundance of Flavonifractor(P<0.05),a flavonoid-metabolizing bacterium.Furthermore,Flavonifractor positively correlated with chicken ileum crypt depth(P<0.05).While BC+PC had a limited effect on cecal microbiota structure,the PC group had a very similar microbial composition to BC+PC,suggesting that the effect of PC at the distal end of the gut overshadowed those of BC.Conclusions We demonstrated the synergistic enhancement of gut health regulation in broiler chickens by combining baicalin and probiotic cocktails.Probiotic cocktails enhanced the effects of baicalin and accelerated its metabolism in the ileum,thereby influencing the ileal microbiota structure.This study elucidates the interaction mechanism between probiotic cocktails and plant extract additives within the host microbiota.These findings provide compelling evidence for the future development of feed additive combinations.展开更多
Genes encoding enzymes involved in the lignin biosynthesis through phenylpropanoid pathway were not only associated with the lignin content, but also related to the abiotic stress resistances. As far as the production...Genes encoding enzymes involved in the lignin biosynthesis through phenylpropanoid pathway were not only associated with the lignin content, but also related to the abiotic stress resistances. As far as the production of liquid biofuels and cultivation within the marginal land are concerned, switchgrass could be the better candidate to determine the relationship between lower lignin content and physiological function under stress. Caffeoyl-coenzyme A 3-O-methyltransferase(CCoAOMT) is a key enzyme for the methylation reaction of lignin biosynthesis. For this purpose, we cloned a CCoAOMT gene from switchgrass and identified its expression patterns under abiotic stresses. The full-length CCoAOMT gene, designated PvCCoAOMT(Gen Bank accession no. KF041775), was 1 005-bp in length, has an opening reading frame of 777 nucleotides encoding a 258-amino acid protein. The deduced amino acid sequence of PvCCoAOMT shared a high degree of similarity(up to 98%) with CCoAOMTs from Panicum virgatum allele(BAO20881), Sorghum bicolor(XP002436550) and Zea mays(NP001131288). Using quantitative real-time PCR(qRT-PCR), the significant upregulation of PvCCoAOMT was observed in stem tissues at a later stage(24 h) after drought treatment, with the transcript level increasing 33-fold compared that of the controls. Moderate and insignificant inductions of PvCCoAOMT were also observed in both stems and leaves during the later stages after cold(48 h in stems, 12 h in leaves) and mechanical wounding(48 h in stems, 12 h in leaves) treatments, respectively. Our results showed the different expression patterns of PvCCoAOMT in drought, cold and mechanical wounding stresses. PvCCoAOMT can be highly induced by drought and cold stresses, which indicates that it may play a role in plant abiotic stress resistance, particularly in the regulation of drought and cold resistance.展开更多
Background: Different production systems and climates could lead to genotype-by-environment(G × E) interactions between populations, and the inclusion of G × E interactions is becoming essential in breeding ...Background: Different production systems and climates could lead to genotype-by-environment(G × E) interactions between populations, and the inclusion of G × E interactions is becoming essential in breeding decisions. The objective of this study was to investigate the performance of multi-trait models in genomic prediction in a limited number of environments with G × E interactions.Results: In total, 2,688 and 1,384 individuals with growth and reproduction phenotypes, respectively, from two Yorkshire pig populations with similar genetic backgrounds were genotyped with the PorcineSNP80 panel.Single-and multi-trait models with genomic best linear unbiased prediction(GBLUP) and BayesC π were implemented to investigate their genomic prediction abilities with 20 replicates of five-fold cross-validation.Our results regarding between-environment genetic correlations of growth and reproductive traits(ranging from 0.618 to 0.723) indicated the existence of G × E interactions between these two Yorkshire pig populations. For single-trait models, genomic prediction with GBLUP was only 1.1% more accurate on average in the combined population than in single populations, and no significant improvements were obtained by BayesC π for most traits. In addition, single-trait models with either GBLUP or BayesC π produced greater bias for the combined population than for single populations. However, multi-trait models with GBLUP and BayesC π better accommodated G × E interactions,yielding 2.2% – 3.8% and 1.0% – 2.5% higher prediction accuracies for growth and reproductive traits, respectively,compared to those for single-trait models of single populations and the combined population. The multi-trait models also yielded lower bias and larger gains in the case of a small reference population. The smaller improvement in prediction accuracy and larger bias obtained by the single-trait models in the combined population was mainly due to the low consistency of linkage disequilibrium between the two populations, which also caused the BayesC π method to always produce the largest standard error in marker effect estimation for the combined population.Conclusions: In conclusion, our findings confirmed that directly combining populations to enlarge the reference population is not efficient in improving the accuracy of genomic prediction in the presence of G × E interactions, while multi-trait models perform better in a limited number of environments with G × E interactions.展开更多
Background: Complex vertebral malformation (CVM) and bovine leukocyte adhesion deficiency (BLAD) are two autosomal recessive lethal genetic defects frequently occurring in Holstein cattle, identifiable by single nucle...Background: Complex vertebral malformation (CVM) and bovine leukocyte adhesion deficiency (BLAD) are two autosomal recessive lethal genetic defects frequently occurring in Holstein cattle, identifiable by single nucleotide polymorphisms. The objective of this study is to develop a rapid and reliable genotyping assay to screen the active Holstein sires and determine the carrier frequency of CVM and BLAD in Chinese dairy cattle population. Results: We developed real-time PCR-based assays for discrimination of wild-type and defective alleles, so that carriers can be detected. Only one step was required after the DNA extraction from the sample and time consumption was about 2 hours. A total of 587 Chinese Holstein bulls were assayed, and fifty-six CVM-carriers and eight BLAD-carriers were identified, corresponding to heterozygote carrier frequencies of 9.54% and 1.36%, respectively. The pedigree analysis showed that most of the carriers could be traced back to the common ancestry, Osborndale Ivanhoe for BLAD and Pennstate Ivanhoe Star for CVM. Conclusions: These results demonstrate that real-time PCR is a simple, rapid and reliable assay for BLAD and CVM defective allele detection. The high frequency of the CVM allele suggests that implementing a routine testing system is necessary to gradually eradicate the deleterious gene from the Chinese Holstein population.展开更多
Background:Salmonella enterica serovar Enteritidis(SE),as a major cause of foodbom illness,infects humans mainly through the egg.However,the symptom of laying hens usually is not typical and hard to diagnosis.In the p...Background:Salmonella enterica serovar Enteritidis(SE),as a major cause of foodbom illness,infects humans mainly through the egg.However,the symptom of laying hens usually is not typical and hard to diagnosis.In the present study,it is studied that the influences of SE infection on layers’ performance,egg quality and blood biochemical indicators.It will help us to improve the strategy to control SE infection in commercial layers.One hundred layers at 20 wk of age were divided into 2 groups,60 hens for experiment and others for control.The experiment group was fed with the dosage of 10~8 CFU SE per hen.The specific PCR was used to detect the deposition of SE.On the 8 d after SE infection,10 hens from the control group and 30 hens from the experimenta group were slaughtered to detect the SE colonization.The production performance,egg quality and blood biochemical indices were also analyzed.Results:The results showed that the colonization rate of SE was highest in caecum contents(55.17%) and lowest in vagina(17.24%).For the eggs the detection rate of SE was highest on the eggshell(80.00%) and lowest in yolk(18.81%).SE infection had no significant influence on production performance and egg qualities(P > 0.05).The difference of laying rate between the experimental and control groups was less than 0.30%,and both were approximately equal to 82.00%.The blood analysis showed that the aspartic aminotransferase(AST) and alanine aminotransferase(ALT) of experimental group was significantly higher than those of control group(P < 0.05).For experimental and control groups AST values were 236.22 U/l and 211.84 U/l respectively,and ALT values were32.19 U/l and 24.55 U/l.All of coefficients were less than 20%.The colonization of SE in organs increases the enzyme activities of AST and ALT in blood.Conclusions:SE in feed could invade the oviduct and infect the forming eggs.It significantly increased the concentration of ALT and AST in blood.However,SE infection was hard to be observed from the appearances of layer and egg.It might be a dangerous risk to human health.展开更多
In genomic selection, prediction accuracy is highly driven by the size of animals in the reference population(RP).Combining related populations from different countries and regions or using a related population with l...In genomic selection, prediction accuracy is highly driven by the size of animals in the reference population(RP).Combining related populations from different countries and regions or using a related population with large size of RP has been considered to be viable strategies in cattle breeding. The genetic relationship between related populations is important for improving the genomic predictive ability. In this study, we used 122 French bulls as test individuals. The genomic estimated breeding values(GEBVs) evaluated using French RP, America RP and Chinese RP were compared.The results showed that the GEBVs were in higher concordance using French RP and American RP compared with using Chinese population. The persistence analysis, kinship analysis and the principal component analysis(PCA) were performed for 270 French bulls, 270 American bulls and 270 Chinese bulls to interpret the results. All the analyses illustrated that the genetic relationship between French bulls and American bulls was closer compared with Chinese bulls. Another reason could be the size of RP in China was smaller than the other two RPs. In conclusion, using RP of a related population to predict GEBVs of the animals in a target population is feasible when these two populations have a close genetic relationship and the related population is large.展开更多
Background: The p21-activated kinase 1 (PAK1) is essential for mitosis and plays an important role in the regulation of microtubule assembly during oocyte meiotic maturation in mice; however, little is known about its...Background: The p21-activated kinase 1 (PAK1) is essential for mitosis and plays an important role in the regulation of microtubule assembly during oocyte meiotic maturation in mice; however, little is known about its role in porcine oocytes. Result: Total p21-activated kinase 1 (PAK1) and phosphorylated PAK1 at Thr423 (PAK1 Thr423 ) were consistently expressed in porcine oocytes from the germinal vesicle (GV) to the second metaphase (MII) stages, but phosphorylation of histone H3 at Ser10 (H3 Ser10 ) was only expressed after the GV stage. Immunofluorescence analysis revealed that PAK1 Thr423 and H3 Ser10 colocalized on chromosomes after the GV stage. Blocking of endogenous PAK1 Thr423 by injecting a specific antibody decreased the phosphorylation level of H3 Ser10 ; however, it had no impact on chromatin condensation, meiotic progression, cleavage rate of blastomeres or the rate of blastocyst formation. Conclusion: Phosphorylation of PAK1 Thr423 is a spontaneous activation process and the activated PAK1 Thr423 can promote the phosphorylation of H3 Ser10 ; however, this pathway is not required for meiotic maturation of porcine oocytes or early embryonic development.展开更多
Background:Heterosis is an important biological phenomenon that has been extensively utilized in agricultural breeding.However,negative heterosis is also pervasively observed in nature,which can cause unfavorable impa...Background:Heterosis is an important biological phenomenon that has been extensively utilized in agricultural breeding.However,negative heterosis is also pervasively observed in nature,which can cause unfavorable impacts on production performance.Compared with systematic studies of positive heterosis,the phenomenon of negative heterosis has been largely ignored in genetic studies and breeding programs,and the genetic mechanism of this phenomenon has not been thoroughly elucidated to date.Here,we used chickens,the most common agricultural animals worldwide,to determine the genetic and molecular mechanisms of negative heterosis.Results:We performed reciprocal crossing experiments with two distinct chicken lines and found that the body weight presented widely negative heterosis in the early growth of chickens.Negative heterosis of carcass traits was more common than positive heterosis,especially breast muscle mass,which was over−40%in reciprocal progenies.Genome-wide gene expression pattern analyses of breast muscle tissues revealed that nonadditivity,including dominance and overdominace,was the major gene inheritance pattern.Nonadditive genes,including a substantial number of genes encoding ATPase and NADH dehydrogenase,accounted for more than 68%of differentially expressed genes in reciprocal crosses(4257 of 5587 and 3617 of 5243,respectively).Moreover,nonadditive genes were significantly associated with the biological process of oxidative phosphorylation,which is the major metabolic pathway for energy release and animal growth and development.The detection of ATP content and ATPase activity for purebred and crossbred progenies further confirmed that chickens with lower muscle yield had lower ATP concentrations but higher hydrolysis activity,which supported the important role of oxidative phosphorylation in negative heterosis for growth traits in chickens.Conclusions:These findings revealed that nonadditive genes and their related oxidative phosphorylation were the major genetic and molecular factors in the negative heterosis of growth in chickens,which would be beneficial to future breeding strategies.展开更多
Damaged eggshells result in losses of eggs.The genetic mechanism of variable eggshell strength is still unclear.The current study was conducted to verify whether the eggshell calcification related genes,CALB1,SPP1,DMP...Damaged eggshells result in losses of eggs.The genetic mechanism of variable eggshell strength is still unclear.The current study was conducted to verify whether the eggshell calcification related genes,CALB1,SPP1,DMP4,BMP2 and SLIT2,were associated with eggshell mechanical property.For this purpose quantitative PCR(q-PCR) analysis was performed to detect gene expression between two groups of hens laying strong and weak eggs.The hens were selected from 360 White Leghorn layers at 60 wk to ensure that the strong and weak eggs differed significantly in breaking strength but not in eggshell thickness and weight.Using this special strong/weak eggshell model,we found that the expression of CALB1 in the uterus of strong shell group was about 3-fold higher(P<0.05) than that in weak shell group.The DMP4 expression was significantly higher(2-fold,P<0.05) in the uterus of weak shell group than that in strong shell group.However,no difference was observed for genes of SPP1,SLIT2 and BMP2 between these two groups.The current study provides a new insight to investigate the association of candidate genes with eggshell mechanical property.展开更多
Background:At present,vitrification has been widely applied to humans,mice and farm animals.To improve the efficiency of vitrification in straw,bovine oocytes were used to test a new two-step vitrification method in t...Background:At present,vitrification has been widely applied to humans,mice and farm animals.To improve the efficiency of vitrification in straw,bovine oocytes were used to test a new two-step vitrification method in this study.Results:When in vitro matured oocytes were exposed to 20%ethylene glycol(EG20) for 5 min and 40%ethylene glycol(EG40) for 30 s,followed by treatment with 30%glycerol(Gly30),Gly40 or Gly50,a volume expansion was observed in Gly30 and Gly40 but not Gly50.This indicates that the intracellular osmotic pressure after a 30 s differs between EG40 and ranged between Gly40(approximately 5.6 mol/L) and Gly50(approximately 7.0 mol/L).Since oocytes are in EG40 just for only a short period of time(30 s) and at a lower temperature(4℃),we hypothesize that the main function of this step in to induce dehydration.Based on these results,we omitted the EG40 step,before oocytes were pretreated in EG20 for 5 min,exposed to pre-cooled(4℃) Gly50,for 30 s,and then dipped into liquid nitrogen.After warming,81.1%of the oocytes survived,and the surviving oocytes developed into cleavage stage embryos(63.5%) or blastocysts(20.0%) after parthenogenetic activation.Conclusions:These results demonstrate that in a two-step vitrification procedure,the permeability effect in the second step is not necessary.It is possible that the second step is only required to provide adequate osmotic pressure to condense the intracellular concentration of CPAs to a level required for successful vitrification.展开更多
This review focuses on the diversity of immunoglobulin (Ig) genes and Ig isotypes that are expressed in domestic animals. Four livestock species-cattle, sheep, pigs, and horses-express a full range of Ig heavy chains ...This review focuses on the diversity of immunoglobulin (Ig) genes and Ig isotypes that are expressed in domestic animals. Four livestock species-cattle, sheep, pigs, and horses-express a full range of Ig heavy chains (IgHs), including μ, δ, γ, ε, and α. Two poultry species (chickens and ducks) express three IgH isotypes, μ, υ, and α, but not δ. The κ and λ light chains are both utilized in the four livestock species, but only the λ chain is expressed in poultry. V(D)J recombination, somatic hypermutation (SHM), and gene conversion (GC) are three distinct mechanisms by which immunoglobulin variable region diversity is generated. Different domestic animals may use distinct means to diversify rearranged variable regions of Ig genes.展开更多
Background Geese are among the most important poultry species in the world.The current generally accepted hypothesis is that the European domestic geese originated from greylag geese(Anser anser),and Chinese domestic ...Background Geese are among the most important poultry species in the world.The current generally accepted hypothesis is that the European domestic geese originated from greylag geese(Anser anser),and Chinese domestic geese have two origins,most of which originated from swan geese(Anser cygnoides),and the Yili goose originated from greylag geese.To explain the origin and demographic history of geese,we selected 14 goose breeds from Europe and China and wild populations of swan and greylag geese,and whole genome sequencing data were obtained for 74 samples.Results Population structure analysis and phylogenetic trees showed that the wild ancestor of Chinese domestic geese,except for Yili,is the swan geese,and the wild ancestor of Chinese Yili and European domestic geese is greylag geese.Analysis of the demographic history suggests that the domestication of Chinese geese occurred~3499 years ago and that of the European geese occurred~7552 years ago.Furthermore,gene flow was observed between domestic geese and their wild ancestors.Analysis of introgression showed that Yili geese had been introgressed by Chinese domestic geese,and the body size of Yili geese may be influenced by introgression events of some growthrelated genes,including IGF-1.Conclusions Our study provides evidence for the origin of geese at the genome-wide level and advances the understanding of the history of goose domestication and the traits affected by introgression events.展开更多
The rapid development of biotechnology has facilitated our understanding of the biological functions of candidate genes for important economic traits in farm animals.Molecular breeding by gene editing has greatly revo...The rapid development of biotechnology has facilitated our understanding of the biological functions of candidate genes for important economic traits in farm animals.Molecular breeding by gene editing has greatly revolutionized the breeding of farm animals.Through gene editing and embryo manipulation,breeds with designed economic or disease-resistant traits can be readily generated.Along with this fast progress,the safety assessment of gene-edited farm animals has attracted public and regulatory attention.This review summarizes the research progress of gene editing in farm animals,focusing on performance improvement,disease resistance,bioreactors,animal welfare,and environmental friendliness.The limitations and future development of gene editing technology in farm animal breeding are also discussed.展开更多
Background Abdominal fat deposition depends on both the proliferation of preadipocytes and their maturation into adipocytes,which is a well-orchestrated multistep process involving many regulatory molecules.Circular R...Background Abdominal fat deposition depends on both the proliferation of preadipocytes and their maturation into adipocytes,which is a well-orchestrated multistep process involving many regulatory molecules.Circular RNAs(circRNAs)have emergingly been implicated in mammalian adipogenesis.However,circRNA-mediated regulation in chicken adipogenesis remains unclear.Our previous circRNA sequencing data identified a differentially expressed novel circRNA,8:27,886,180|27,889,657,during the adipogenic differentiation of chicken abdominal preadipocytes.This study aimed to investigate the regulatory role of circDOCK7 in the proliferation and adipogenic differentiation of chicken abdominal preadipocytes,and explore its molecular mechanisms of competing endogenous RNA underlying chicken adipogenesis.Results Our results showed that 8:27,886,180|27,889,657 is an exonic circRNA derived from the head-to-tail splicing of exons 19–22 of the dedicator of cytokinesis 7(DOCK7)gene,abbreviated as circDOCK7.CircDOCK7 is mainly distributed in the cytoplasm of chicken abdominal preadipocytes and is stable because of its RNase R resistance and longer half-life.CircDOCK7 is significantly upregulated in the abdominal fat tissues of fat chickens compared to lean chickens,and its expression gradually increases during the proliferation and adipogenic differentiation of chicken abdominal preadipocytes.Functionally,the gain-and loss-of-function experiments showed that circDOCK7 promoted proliferation,G0/G1-to S-phase progression,and glucose uptake capacity of chicken abdominal preadipocytes,in parallel with adipogenic differentiation characterized by remarkably increased intracellular lipid droplet accumulation and triglyceride and acetyl coenzyme A content in differentiated chicken abdominal preadipocytes.Mechanistically,a pull-down assay and a dual-luciferase reporter assay confirmed that circDOCK7 interacted with gga-miR-301b-3p,which was identified as an inhibitor of chicken abdominal adipogenesis.Moreover,the ACSL1 gene was demonstrated to be a direct target of gga-miR-301b-3p.Chicken ACSL1 protein is localized in the endoplasmic reticulum and mitochondria of chicken abdominal preadipocytes and acts as an adipogenesis accelerator.Rescue experiments showed that circDOCK7 could counteract the inhibitory effects of gga-miR-301b-3p on ACSL1 mRNA abundance as well as the proliferation and adipogenic differentiation of chicken abdominal preadipocytes.Conclusions CircDOCK7 serves as a miRNA sponge that directly sequesters gga-miR-301b-3p away from the ACSL1 gene,thus augmenting adipogenesis in chickens.These findings may elucidate a new regulatory mechanism underlying abdominal fat deposition in chickens.展开更多
Background The fat deposition has a crucial role in animal meat flavor,and fat deposition-related traits are vital for breeding in the commercial duck industry.Avian fat-related traits are typical complex phenotypes,w...Background The fat deposition has a crucial role in animal meat flavor,and fat deposition-related traits are vital for breeding in the commercial duck industry.Avian fat-related traits are typical complex phenotypes,which need a large amount of data to analyze the genetic loci.Results In this study,we performed a new phenotypic analysis of fat traits and genotyped whole-genome varia-tions for 1,246 ducks,and combed with previous GWAS data to reach 1,880 ducks for following analysis.The carcass composition traits,subcutaneous fat weight(SFW),subcutaneous fat percentage(SFP),abdominal fat weight(AFW),abdominal fat percentage(AFP)and the body weight of day 42(BW42)for each duck were collected.We identified a set of new loci that affect the traits related to fat deposition in avian.Among these loci,ceroid-lipofuscinosis,neuronal 8(CLN8)is a novel candidate gene controlling fat deposition.We investigated its novel function and regulation in avian adipogenesis.Five significant SNPs(the most significant SNP,P-value=21.37E-12)and a single haplotype were detected in the upstream of CLN8 for subcutaneous fat percentage.Subsequently,luciferase assay demonstrated that 5 linked SNPs in the upstream of the CLN8 gene significantly decreased the transcriptional activity of CLN8.Further,ATAC-seq analysis showed that transcription factor binding sites were identified in a region close to the haplotype.A set of luciferase reporter gene vectors that contained different deletion fragments of the CLN8 promoter were con-structed,and the core promoter area of CLN8 was finally identified in the-1,884/-1,207 bp region of the 5′flanking sequences,which contains adipogenesis-related transcription factors binding sites.Moreover,the over-expression of CLN8 can remarkably facilitate adipocyte differentiation in ICPs.Consistent with these,the global transcriptome profiling and functional analysis of the over-expressed CLN8 in the cell line further revealed that the lipid biosynthetic process during the adipogenesis was significantly enriched.Conclusions Our results demonstrated that CLN8 is a positive regulator of avian adipocyte differentiation.These findings identify a novel function of CLN8 in adipocyte differentiation,which provides important clues for the further study of the mechanism of avian fat deposition.展开更多
Background:SCNT(somatic cell nuclear transfer)is of great significance to biological research and also to the livestock breeding.However,the survival rate of the SCNT cloned animals is relatively low compared to other...Background:SCNT(somatic cell nuclear transfer)is of great significance to biological research and also to the livestock breeding.However,the survival rate of the SCNT cloned animals is relatively low compared to other transgenic methods.This indicates the potential epigenetic variations between them.DNA methylation is a key marker of mammalian epigenetics and its alterations will lead to phenotypic differences.In this study,ASMT(acetylserotonin-Omethyltransferase)ovarian overexpression transgenic goat was produced by using SCNT.To investigate whether there are epigenetic differences between cloned and WT(wild type)goats,WGBS(whole-genome bisulfite sequencing)was used to measure the whole-genome methylation of these animals.Results:It is observed that the different m Cp G sites are mainly present in the intergenic and intronic regions between cloned and WT animals,and their CG-type methylation sites are strongly correlated.DMR(differentially methylated region)lengths are located around 1000 bp,mainly distributed in the exonic,intergenic and intronic functional domains.A total of 56 and 36 DMGs(differentially methylated genes)were identified by GO and KEGG databases,respectively.Functional annotation showed that DMGs were enriched in biological-process,cellularcomponent,molecular-function and other signaling pathways.A total of 10 identical genes related to growth and development were identified in GO and KEGG databases.Conclusion:The differences in methylation genes among the tested animals have been identified.A total of 10 DMGs associated with growth and development were identified between cloned and WT animals.The results indicate that the differential patterns of DNA methylation between the cloned and WT goats are probably caused by the SCNT.These novel observations will help us to further identify the unveiled mechanisms of somatic cell cloning technology,particularly in goats.展开更多
基金supported by the International S&T Cooperation Program (2008DFA31120)the National Importation of Agriculture Advanced Technology 948 Project of China (2010-C14)+2 种基金the Special Fund for Agro-Scientific Research in the Public Interest,China (nyhyzx07-36)the National Key Technologies R&D Program of China (2006BAD04A01)the Ear-marked Fund for Modern Agro-Industry Technology Research System,China (CARS-37)
文摘Current study adopted gene flow theory and selection index method to compare the breeding efficiency of three breeding plans in the Chinese Holstein cattle using ZPLAN software. Simulated conventional progeny-testing program (PT) and young sire program (YS) were compared with breeding program using genomic selection (GS) taking parameters derived from Chinese Holstein breeding system. The results showed that, GS shortened generation interval by 1.5-2.2 years, and increased the genetic progress by 30-50%, comparing to PT and YS, respectively. Economic analysis showed that GS could obtain a higher breeding efficiency, being 119 and 97% higher than that of PT and YS, respectively; and GS was also powerful in improving functional traits with a low heritability. Main factors affecting breeding efficiency in GS were further discussed, including selection intensity, accuracy and the cost of SNP genotyping. Our finding provided references for future designing and implementing GS in Chinese dairy population.
基金supported by National High Technology and Science Development Plan of China(No.2011AA100302)Program for New Century Excellent Talents in University(No.NCET-11-0480)Program for Changjiang Scholar and Innovation Research Team in University(IRT1191)and project(CARS-41-K01)
文摘Advances in molecular biotechnology have introduced new generations of molecular markers for use in the genetic improvement of farm animals. Consequently, more accurate genetic information can be obtained to better understand existing animal genetic resources. This review gives a brief summary on the development of genetic markers including both the classical genetic markers and more advanced DNA-based molecular markers. This review will help us better understand the characteristics of different genetic markers and the genetic diversity of animal genetic resources.
基金supported by Strategy Research on Disruptive Technology in Agriculture(China Academy of Engineering,2017-ZD-10-07)supported by grants from the National Key R&D Program(2017YFD0501901+1 种基金2017YFD0501905)the Earmarked Fund for the Innovative Teams of Beijing Swine Industrialization Research Program.National Waterfowl-industry Technology Research System(CARS-42)
文摘Meat and milk production needs to increase ～ 70–80% relative to its current levels for satisfying the human needs in 2050.However,it is impossible to achieve such genetic gain by conventional animal breeding systems.Based on recent advances with regard to in vitro induction of germ cell from pluripotent stem cells,herein we propose a novel embryo-stem cell breeding system.Distinct from the conventional breeding system in farm animals that involves selecting and mating individuals,the novel breeding system completes breeding cycles from parental to offspring embryos directly by selecting and mating embryos in a dish.In comparison to the conventional dairy breeding scheme,this system can rapidly achieve 30–40 times more genetic gain by significantly shortening generation interval and enhancing selection intensity.However,several major obstacles must be overcome before we can fully use this system in livestock breeding,which include derivation and mantaince of pluripotent stem cells in domestic animals,as well as in vitro induction of primordial germ cells,and subsequent haploid gametes.Thus,we also discuss the potential efforts needed in solving the obstacles for application this novel system,and elaborate on their groundbreaking potential in livestock breeding.This novel system would provide a revolutionary animal breeding system by offering an unprecedented opportunity for meeting the fast-growing meat and milk demand of humans.
基金funded in part by grants from the National Natural Science Foundation of China (No.31930105)National Key Research and Development Program of China (2022YFF1000204)China Agriculture Research Systems (CARS-40)。
文摘Background Hepatic steatosis is a prevalent manifestation of fatty liver, that has detrimental effect on the health and productivity of laying hens, resulting in economic losses to the poultry industry. Here, we aimed to systematically investigate the genetic regulatory mechanisms of hepatic steatosis in laying hens.Methods Ninety individuals with the most prominent characteristics were selected from 686 laying hens according to the accumulation of lipid droplets in the liver, and were graded into three groups, including the control, mild hepatic steatosis and severe hepatic steatosis groups. A combination of transcriptome, proteome, acetylome and lipidome analyses, along with bioinformatics analysis were used to screen the key biological processes, modifications and lipids associated with hepatic steatosis.Results The rationality of the hepatic steatosis grouping was verified through liver biochemical assays and RNA-seq. Hepatic steatosis was characterized by increased lipid deposition and multiple metabolic abnormalities. Integration of proteome and acetylome revealed that differentially expressed proteins(DEPs) interacted with differentially acetylated proteins(DAPs) and were involved in maintaining the metabolic balance in the liver. Acetylation alterations mainly occurred in the progression from mild to severe hepatic steatosis, i.e., the enzymes in the fatty acid oxidation and bile acid synthesis pathways were significantly less acetylated in severe hepatic steatosis group than that in mild group(P < 0.05). Lipidomics detected a variety of sphingolipids(SPs) and glycerophospholipids(GPs) were negatively correlated with hepatic steatosis(r ≤-0.5, P < 0.05). Furthermore, the severity of hepatic steatosis was associated with a decrease in cholesterol and bile acid synthesis and an increase in exogenous cholesterol transport.Conclusions In addition to acquiring a global and thorough picture of hepatic steatosis in laying hens, we were able to reveal the role of acetylation in hepatic steatosis and depict the changes in hepatic cholesterol metabolism. The findings provides a wealth of information to facilitate a deeper understanding of the pathophysiology of fatty liver and contributes to the development of therapeutic strategies.
基金funded by National Key R&D Program of China(2022YFD1300403,2021YFD1300404)China Agriculture Research System program(CARS-40,CARS-41-G11)Beijing Natural Science Foundation(6222036).
文摘Background Baicalin and probiotic cocktails are promising feed additives with broad application prospects.While probiotic cocktails are known to enhance intestinal health,the potential synergistic impact of combining baicalin with probiotic cocktails on the gut health of broiler chickens remains largely unexplored.Therefore,this study aims to investigate the influence of the combined administration of baicalin and probiotic cocktails on the composition of ileal and cecal microbiota in broiler chickens to elucidate the underlying mechanisms responsible for the healthpromoting effects.Results A total of 3201-day-old male Arbor Acres broilers were divided into 4 groups,each with 8 replicates of 10 chicks per replicate.Over a period of 42 d,the birds were fed a basal diet or the same diet supplemented with 37.5 g/t baicalin(BC),1,000 g/t probiotic cocktails(PC),or a combination of both BC(37.5 g/t)and PC(1,000 g/t).The results demonstrated that BC+PC exhibited positive synergistic effects,enhancing intestinal morphology,immune function,and barrier function.This was evidenced by increased VH/CD ratio,sIgA levels,and upregulated expression of occludin and claudin-1(P<0.05).16S rRNA analysis indicated that PC potentiated the effects of BC,particularly in the ileum,where BC+PC significantly increased theα-diversity of the ileal microbiota,altered itsβ-diversity,and increased the relative abundance of Flavonifractor(P<0.05),a flavonoid-metabolizing bacterium.Furthermore,Flavonifractor positively correlated with chicken ileum crypt depth(P<0.05).While BC+PC had a limited effect on cecal microbiota structure,the PC group had a very similar microbial composition to BC+PC,suggesting that the effect of PC at the distal end of the gut overshadowed those of BC.Conclusions We demonstrated the synergistic enhancement of gut health regulation in broiler chickens by combining baicalin and probiotic cocktails.Probiotic cocktails enhanced the effects of baicalin and accelerated its metabolism in the ileum,thereby influencing the ileal microbiota structure.This study elucidates the interaction mechanism between probiotic cocktails and plant extract additives within the host microbiota.These findings provide compelling evidence for the future development of feed additive combinations.
基金provided by the Ministry of Science and Technology, China (2012AA101801, 2014BAD23B00)the National Natural Science Foundation of China(31272493)China Agricultural University (2014FG062)
文摘Genes encoding enzymes involved in the lignin biosynthesis through phenylpropanoid pathway were not only associated with the lignin content, but also related to the abiotic stress resistances. As far as the production of liquid biofuels and cultivation within the marginal land are concerned, switchgrass could be the better candidate to determine the relationship between lower lignin content and physiological function under stress. Caffeoyl-coenzyme A 3-O-methyltransferase(CCoAOMT) is a key enzyme for the methylation reaction of lignin biosynthesis. For this purpose, we cloned a CCoAOMT gene from switchgrass and identified its expression patterns under abiotic stresses. The full-length CCoAOMT gene, designated PvCCoAOMT(Gen Bank accession no. KF041775), was 1 005-bp in length, has an opening reading frame of 777 nucleotides encoding a 258-amino acid protein. The deduced amino acid sequence of PvCCoAOMT shared a high degree of similarity(up to 98%) with CCoAOMTs from Panicum virgatum allele(BAO20881), Sorghum bicolor(XP002436550) and Zea mays(NP001131288). Using quantitative real-time PCR(qRT-PCR), the significant upregulation of PvCCoAOMT was observed in stem tissues at a later stage(24 h) after drought treatment, with the transcript level increasing 33-fold compared that of the controls. Moderate and insignificant inductions of PvCCoAOMT were also observed in both stems and leaves during the later stages after cold(48 h in stems, 12 h in leaves) and mechanical wounding(48 h in stems, 12 h in leaves) treatments, respectively. Our results showed the different expression patterns of PvCCoAOMT in drought, cold and mechanical wounding stresses. PvCCoAOMT can be highly induced by drought and cold stresses, which indicates that it may play a role in plant abiotic stress resistance, particularly in the regulation of drought and cold resistance.
基金supported by grants from the earmarked fund for China Agriculture Research System (CARS-35)Modern Agriculture Science and Technology Key Project of Hebei Province (19226376D)+2 种基金the National Key Research and Development Project (SQ2019YFE00771)the National Natural Science Foundation of China (31671327)Major Project of Selection for New Livestock and Poultry Breeds of Zhejiang Province (2016C02054–5)。
文摘Background: Different production systems and climates could lead to genotype-by-environment(G × E) interactions between populations, and the inclusion of G × E interactions is becoming essential in breeding decisions. The objective of this study was to investigate the performance of multi-trait models in genomic prediction in a limited number of environments with G × E interactions.Results: In total, 2,688 and 1,384 individuals with growth and reproduction phenotypes, respectively, from two Yorkshire pig populations with similar genetic backgrounds were genotyped with the PorcineSNP80 panel.Single-and multi-trait models with genomic best linear unbiased prediction(GBLUP) and BayesC π were implemented to investigate their genomic prediction abilities with 20 replicates of five-fold cross-validation.Our results regarding between-environment genetic correlations of growth and reproductive traits(ranging from 0.618 to 0.723) indicated the existence of G × E interactions between these two Yorkshire pig populations. For single-trait models, genomic prediction with GBLUP was only 1.1% more accurate on average in the combined population than in single populations, and no significant improvements were obtained by BayesC π for most traits. In addition, single-trait models with either GBLUP or BayesC π produced greater bias for the combined population than for single populations. However, multi-trait models with GBLUP and BayesC π better accommodated G × E interactions,yielding 2.2% – 3.8% and 1.0% – 2.5% higher prediction accuracies for growth and reproductive traits, respectively,compared to those for single-trait models of single populations and the combined population. The multi-trait models also yielded lower bias and larger gains in the case of a small reference population. The smaller improvement in prediction accuracy and larger bias obtained by the single-trait models in the combined population was mainly due to the low consistency of linkage disequilibrium between the two populations, which also caused the BayesC π method to always produce the largest standard error in marker effect estimation for the combined population.Conclusions: In conclusion, our findings confirmed that directly combining populations to enlarge the reference population is not efficient in improving the accuracy of genomic prediction in the presence of G × E interactions, while multi-trait models perform better in a limited number of environments with G × E interactions.
基金supported by the National Key Technologies R & D Program (2011BAD28B02)China Agriculture Research System (CARS-37)
文摘Background: Complex vertebral malformation (CVM) and bovine leukocyte adhesion deficiency (BLAD) are two autosomal recessive lethal genetic defects frequently occurring in Holstein cattle, identifiable by single nucleotide polymorphisms. The objective of this study is to develop a rapid and reliable genotyping assay to screen the active Holstein sires and determine the carrier frequency of CVM and BLAD in Chinese dairy cattle population. Results: We developed real-time PCR-based assays for discrimination of wild-type and defective alleles, so that carriers can be detected. Only one step was required after the DNA extraction from the sample and time consumption was about 2 hours. A total of 587 Chinese Holstein bulls were assayed, and fifty-six CVM-carriers and eight BLAD-carriers were identified, corresponding to heterozygote carrier frequencies of 9.54% and 1.36%, respectively. The pedigree analysis showed that most of the carriers could be traced back to the common ancestry, Osborndale Ivanhoe for BLAD and Pennstate Ivanhoe Star for CVM. Conclusions: These results demonstrate that real-time PCR is a simple, rapid and reliable assay for BLAD and CVM defective allele detection. The high frequency of the CVM allele suggests that implementing a routine testing system is necessary to gradually eradicate the deleterious gene from the Chinese Holstein population.
基金supported by National System for Layer Production Technology of China(CARS-41)Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China "Study on Poultry Eggs and Meat Detection Technology"(IRT0945)Chinese Universities Scientific Fund(2013QJ069)
文摘Background:Salmonella enterica serovar Enteritidis(SE),as a major cause of foodbom illness,infects humans mainly through the egg.However,the symptom of laying hens usually is not typical and hard to diagnosis.In the present study,it is studied that the influences of SE infection on layers’ performance,egg quality and blood biochemical indicators.It will help us to improve the strategy to control SE infection in commercial layers.One hundred layers at 20 wk of age were divided into 2 groups,60 hens for experiment and others for control.The experiment group was fed with the dosage of 10~8 CFU SE per hen.The specific PCR was used to detect the deposition of SE.On the 8 d after SE infection,10 hens from the control group and 30 hens from the experimenta group were slaughtered to detect the SE colonization.The production performance,egg quality and blood biochemical indices were also analyzed.Results:The results showed that the colonization rate of SE was highest in caecum contents(55.17%) and lowest in vagina(17.24%).For the eggs the detection rate of SE was highest on the eggshell(80.00%) and lowest in yolk(18.81%).SE infection had no significant influence on production performance and egg qualities(P > 0.05).The difference of laying rate between the experimental and control groups was less than 0.30%,and both were approximately equal to 82.00%.The blood analysis showed that the aspartic aminotransferase(AST) and alanine aminotransferase(ALT) of experimental group was significantly higher than those of control group(P < 0.05).For experimental and control groups AST values were 236.22 U/l and 211.84 U/l respectively,and ALT values were32.19 U/l and 24.55 U/l.All of coefficients were less than 20%.The colonization of SE in organs increases the enzyme activities of AST and ALT in blood.Conclusions:SE in feed could invade the oviduct and infect the forming eggs.It significantly increased the concentration of ALT and AST in blood.However,SE infection was hard to be observed from the appearances of layer and egg.It might be a dangerous risk to human health.
基金supported by the earmarked fund for China Agriculture Research System(CARS-36)the National Natural Science Foundation of China(31671327,31701077,31371258)+2 种基金the Program for Changjiang Scholar and Innovation Research Team in University(Grant No.IRT1191)Anhui Science and Technology Key Project(17030701008)Anhui Academy of Agricultural Sciences Key Laboratory Project(18S0404)
文摘In genomic selection, prediction accuracy is highly driven by the size of animals in the reference population(RP).Combining related populations from different countries and regions or using a related population with large size of RP has been considered to be viable strategies in cattle breeding. The genetic relationship between related populations is important for improving the genomic predictive ability. In this study, we used 122 French bulls as test individuals. The genomic estimated breeding values(GEBVs) evaluated using French RP, America RP and Chinese RP were compared.The results showed that the GEBVs were in higher concordance using French RP and American RP compared with using Chinese population. The persistence analysis, kinship analysis and the principal component analysis(PCA) were performed for 270 French bulls, 270 American bulls and 270 Chinese bulls to interpret the results. All the analyses illustrated that the genetic relationship between French bulls and American bulls was closer compared with Chinese bulls. Another reason could be the size of RP in China was smaller than the other two RPs. In conclusion, using RP of a related population to predict GEBVs of the animals in a target population is feasible when these two populations have a close genetic relationship and the related population is large.
基金supported by grants from the National High-Tech R&D Program (No. 2011AA100303)the National Key Technology R&D Program (No. 2011BAD19B01)the National Natural Science Foundation of China(No. 31271253)
文摘Background: The p21-activated kinase 1 (PAK1) is essential for mitosis and plays an important role in the regulation of microtubule assembly during oocyte meiotic maturation in mice; however, little is known about its role in porcine oocytes. Result: Total p21-activated kinase 1 (PAK1) and phosphorylated PAK1 at Thr423 (PAK1 Thr423 ) were consistently expressed in porcine oocytes from the germinal vesicle (GV) to the second metaphase (MII) stages, but phosphorylation of histone H3 at Ser10 (H3 Ser10 ) was only expressed after the GV stage. Immunofluorescence analysis revealed that PAK1 Thr423 and H3 Ser10 colocalized on chromosomes after the GV stage. Blocking of endogenous PAK1 Thr423 by injecting a specific antibody decreased the phosphorylation level of H3 Ser10 ; however, it had no impact on chromatin condensation, meiotic progression, cleavage rate of blastomeres or the rate of blastocyst formation. Conclusion: Phosphorylation of PAK1 Thr423 is a spontaneous activation process and the activated PAK1 Thr423 can promote the phosphorylation of H3 Ser10 ; however, this pathway is not required for meiotic maturation of porcine oocytes or early embryonic development.
基金supported by the National Natural Science Foundation of China(No.31930105)China Agriculture Research Systems(CARS-40)China Postdoctoral Science Foundation(No.2020 M680028).
文摘Background:Heterosis is an important biological phenomenon that has been extensively utilized in agricultural breeding.However,negative heterosis is also pervasively observed in nature,which can cause unfavorable impacts on production performance.Compared with systematic studies of positive heterosis,the phenomenon of negative heterosis has been largely ignored in genetic studies and breeding programs,and the genetic mechanism of this phenomenon has not been thoroughly elucidated to date.Here,we used chickens,the most common agricultural animals worldwide,to determine the genetic and molecular mechanisms of negative heterosis.Results:We performed reciprocal crossing experiments with two distinct chicken lines and found that the body weight presented widely negative heterosis in the early growth of chickens.Negative heterosis of carcass traits was more common than positive heterosis,especially breast muscle mass,which was over−40%in reciprocal progenies.Genome-wide gene expression pattern analyses of breast muscle tissues revealed that nonadditivity,including dominance and overdominace,was the major gene inheritance pattern.Nonadditive genes,including a substantial number of genes encoding ATPase and NADH dehydrogenase,accounted for more than 68%of differentially expressed genes in reciprocal crosses(4257 of 5587 and 3617 of 5243,respectively).Moreover,nonadditive genes were significantly associated with the biological process of oxidative phosphorylation,which is the major metabolic pathway for energy release and animal growth and development.The detection of ATP content and ATPase activity for purebred and crossbred progenies further confirmed that chickens with lower muscle yield had lower ATP concentrations but higher hydrolysis activity,which supported the important role of oxidative phosphorylation in negative heterosis for growth traits in chickens.Conclusions:These findings revealed that nonadditive genes and their related oxidative phosphorylation were the major genetic and molecular factors in the negative heterosis of growth in chickens,which would be beneficial to future breeding strategies.
基金funded by the National Natural Science Foundation of China(31472084)the National High Technology Research and Development Program of China(2013AA102501)+2 种基金the National Key Technology R&D Program of China(2011BAD28B03)the Programs for Changjiang Scholars and Innovative Research in University,China(IRT1191)the China Agriculture Research Systems(CARS-41)
文摘Damaged eggshells result in losses of eggs.The genetic mechanism of variable eggshell strength is still unclear.The current study was conducted to verify whether the eggshell calcification related genes,CALB1,SPP1,DMP4,BMP2 and SLIT2,were associated with eggshell mechanical property.For this purpose quantitative PCR(q-PCR) analysis was performed to detect gene expression between two groups of hens laying strong and weak eggs.The hens were selected from 360 White Leghorn layers at 60 wk to ensure that the strong and weak eggs differed significantly in breaking strength but not in eggshell thickness and weight.Using this special strong/weak eggshell model,we found that the expression of CALB1 in the uterus of strong shell group was about 3-fold higher(P<0.05) than that in weak shell group.The DMP4 expression was significantly higher(2-fold,P<0.05) in the uterus of weak shell group than that in strong shell group.However,no difference was observed for genes of SPP1,SLIT2 and BMP2 between these two groups.The current study provides a new insight to investigate the association of candidate genes with eggshell mechanical property.
基金supported by the National "863" Project Foundation of China(No.2011AA100303)the National Science and Technology Support Projects of China(No.2011BAD19B01)
文摘Background:At present,vitrification has been widely applied to humans,mice and farm animals.To improve the efficiency of vitrification in straw,bovine oocytes were used to test a new two-step vitrification method in this study.Results:When in vitro matured oocytes were exposed to 20%ethylene glycol(EG20) for 5 min and 40%ethylene glycol(EG40) for 30 s,followed by treatment with 30%glycerol(Gly30),Gly40 or Gly50,a volume expansion was observed in Gly30 and Gly40 but not Gly50.This indicates that the intracellular osmotic pressure after a 30 s differs between EG40 and ranged between Gly40(approximately 5.6 mol/L) and Gly50(approximately 7.0 mol/L).Since oocytes are in EG40 just for only a short period of time(30 s) and at a lower temperature(4℃),we hypothesize that the main function of this step in to induce dehydration.Based on these results,we omitted the EG40 step,before oocytes were pretreated in EG20 for 5 min,exposed to pre-cooled(4℃) Gly50,for 30 s,and then dipped into liquid nitrogen.After warming,81.1%of the oocytes survived,and the surviving oocytes developed into cleavage stage embryos(63.5%) or blastocysts(20.0%) after parthenogenetic activation.Conclusions:These results demonstrate that in a two-step vitrification procedure,the permeability effect in the second step is not necessary.It is possible that the second step is only required to provide adequate osmotic pressure to condense the intracellular concentration of CPAs to a level required for successful vitrification.
文摘This review focuses on the diversity of immunoglobulin (Ig) genes and Ig isotypes that are expressed in domestic animals. Four livestock species-cattle, sheep, pigs, and horses-express a full range of Ig heavy chains (IgHs), including μ, δ, γ, ε, and α. Two poultry species (chickens and ducks) express three IgH isotypes, μ, υ, and α, but not δ. The κ and λ light chains are both utilized in the four livestock species, but only the λ chain is expressed in poultry. V(D)J recombination, somatic hypermutation (SHM), and gene conversion (GC) are three distinct mechanisms by which immunoglobulin variable region diversity is generated. Different domestic animals may use distinct means to diversify rearranged variable regions of Ig genes.
基金funded by the Open Project of Xinjiang Production&Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basinthe National Nature Science Foundation of China (grant numbers:BRZD2104 and 31960648)the Joint Plan of Liaoning Province in the field of Livelihood Science and Technology (Rural Revitalization Science and Technology Support)。
文摘Background Geese are among the most important poultry species in the world.The current generally accepted hypothesis is that the European domestic geese originated from greylag geese(Anser anser),and Chinese domestic geese have two origins,most of which originated from swan geese(Anser cygnoides),and the Yili goose originated from greylag geese.To explain the origin and demographic history of geese,we selected 14 goose breeds from Europe and China and wild populations of swan and greylag geese,and whole genome sequencing data were obtained for 74 samples.Results Population structure analysis and phylogenetic trees showed that the wild ancestor of Chinese domestic geese,except for Yili,is the swan geese,and the wild ancestor of Chinese Yili and European domestic geese is greylag geese.Analysis of the demographic history suggests that the domestication of Chinese geese occurred~3499 years ago and that of the European geese occurred~7552 years ago.Furthermore,gene flow was observed between domestic geese and their wild ancestors.Analysis of introgression showed that Yili geese had been introgressed by Chinese domestic geese,and the body size of Yili geese may be influenced by introgression events of some growthrelated genes,including IGF-1.Conclusions Our study provides evidence for the origin of geese at the genome-wide level and advances the understanding of the history of goose domestication and the traits affected by introgression events.
基金supported by the National Key Research and Development Program of China(2021YFA0805900)the 2020 Research Program of Sanya Yazhou Bay Science and Technology City(202002011)+1 种基金the National Natural Science Foundation of China(32002180)the Key Research and Development Program of Hainan Province,China(ZDYF2021SHFZ230)
文摘The rapid development of biotechnology has facilitated our understanding of the biological functions of candidate genes for important economic traits in farm animals.Molecular breeding by gene editing has greatly revolutionized the breeding of farm animals.Through gene editing and embryo manipulation,breeds with designed economic or disease-resistant traits can be readily generated.Along with this fast progress,the safety assessment of gene-edited farm animals has attracted public and regulatory attention.This review summarizes the research progress of gene editing in farm animals,focusing on performance improvement,disease resistance,bioreactors,animal welfare,and environmental friendliness.The limitations and future development of gene editing technology in farm animal breeding are also discussed.
基金the National Key Research and Development Program of China(2021YFD1200803 and 2022YFD1600902)China Agriculture Research System(CARS-40).
文摘Background Abdominal fat deposition depends on both the proliferation of preadipocytes and their maturation into adipocytes,which is a well-orchestrated multistep process involving many regulatory molecules.Circular RNAs(circRNAs)have emergingly been implicated in mammalian adipogenesis.However,circRNA-mediated regulation in chicken adipogenesis remains unclear.Our previous circRNA sequencing data identified a differentially expressed novel circRNA,8:27,886,180|27,889,657,during the adipogenic differentiation of chicken abdominal preadipocytes.This study aimed to investigate the regulatory role of circDOCK7 in the proliferation and adipogenic differentiation of chicken abdominal preadipocytes,and explore its molecular mechanisms of competing endogenous RNA underlying chicken adipogenesis.Results Our results showed that 8:27,886,180|27,889,657 is an exonic circRNA derived from the head-to-tail splicing of exons 19–22 of the dedicator of cytokinesis 7(DOCK7)gene,abbreviated as circDOCK7.CircDOCK7 is mainly distributed in the cytoplasm of chicken abdominal preadipocytes and is stable because of its RNase R resistance and longer half-life.CircDOCK7 is significantly upregulated in the abdominal fat tissues of fat chickens compared to lean chickens,and its expression gradually increases during the proliferation and adipogenic differentiation of chicken abdominal preadipocytes.Functionally,the gain-and loss-of-function experiments showed that circDOCK7 promoted proliferation,G0/G1-to S-phase progression,and glucose uptake capacity of chicken abdominal preadipocytes,in parallel with adipogenic differentiation characterized by remarkably increased intracellular lipid droplet accumulation and triglyceride and acetyl coenzyme A content in differentiated chicken abdominal preadipocytes.Mechanistically,a pull-down assay and a dual-luciferase reporter assay confirmed that circDOCK7 interacted with gga-miR-301b-3p,which was identified as an inhibitor of chicken abdominal adipogenesis.Moreover,the ACSL1 gene was demonstrated to be a direct target of gga-miR-301b-3p.Chicken ACSL1 protein is localized in the endoplasmic reticulum and mitochondria of chicken abdominal preadipocytes and acts as an adipogenesis accelerator.Rescue experiments showed that circDOCK7 could counteract the inhibitory effects of gga-miR-301b-3p on ACSL1 mRNA abundance as well as the proliferation and adipogenic differentiation of chicken abdominal preadipocytes.Conclusions CircDOCK7 serves as a miRNA sponge that directly sequesters gga-miR-301b-3p away from the ACSL1 gene,thus augmenting adipogenesis in chickens.These findings may elucidate a new regulatory mechanism underlying abdominal fat deposition in chickens.
基金supported by the National Key R&D Program of China(2022YFF1000100)National Waterfowl-Industry Technology Research System(CARS-42–09)+1 种基金National Nature Science Foundation of China(31972525,31572388)Beijing Joint Research Program for Germplasm Innovation and New Variety Breeding(G20220628007).
文摘Background The fat deposition has a crucial role in animal meat flavor,and fat deposition-related traits are vital for breeding in the commercial duck industry.Avian fat-related traits are typical complex phenotypes,which need a large amount of data to analyze the genetic loci.Results In this study,we performed a new phenotypic analysis of fat traits and genotyped whole-genome varia-tions for 1,246 ducks,and combed with previous GWAS data to reach 1,880 ducks for following analysis.The carcass composition traits,subcutaneous fat weight(SFW),subcutaneous fat percentage(SFP),abdominal fat weight(AFW),abdominal fat percentage(AFP)and the body weight of day 42(BW42)for each duck were collected.We identified a set of new loci that affect the traits related to fat deposition in avian.Among these loci,ceroid-lipofuscinosis,neuronal 8(CLN8)is a novel candidate gene controlling fat deposition.We investigated its novel function and regulation in avian adipogenesis.Five significant SNPs(the most significant SNP,P-value=21.37E-12)and a single haplotype were detected in the upstream of CLN8 for subcutaneous fat percentage.Subsequently,luciferase assay demonstrated that 5 linked SNPs in the upstream of the CLN8 gene significantly decreased the transcriptional activity of CLN8.Further,ATAC-seq analysis showed that transcription factor binding sites were identified in a region close to the haplotype.A set of luciferase reporter gene vectors that contained different deletion fragments of the CLN8 promoter were con-structed,and the core promoter area of CLN8 was finally identified in the-1,884/-1,207 bp region of the 5′flanking sequences,which contains adipogenesis-related transcription factors binding sites.Moreover,the over-expression of CLN8 can remarkably facilitate adipocyte differentiation in ICPs.Consistent with these,the global transcriptome profiling and functional analysis of the over-expressed CLN8 in the cell line further revealed that the lipid biosynthetic process during the adipogenesis was significantly enriched.Conclusions Our results demonstrated that CLN8 is a positive regulator of avian adipocyte differentiation.These findings identify a novel function of CLN8 in adipocyte differentiation,which provides important clues for the further study of the mechanism of avian fat deposition.
基金Key Research and Development Project of Hainan Province(ZDYF2021XDNY174)Science and Technology Major Project of Inner Mongolia(2021ZD0023–1)National Transgenic Key Project of the Ministry of Agriculture of China(2018ZX0800801B)。
文摘Background:SCNT(somatic cell nuclear transfer)is of great significance to biological research and also to the livestock breeding.However,the survival rate of the SCNT cloned animals is relatively low compared to other transgenic methods.This indicates the potential epigenetic variations between them.DNA methylation is a key marker of mammalian epigenetics and its alterations will lead to phenotypic differences.In this study,ASMT(acetylserotonin-Omethyltransferase)ovarian overexpression transgenic goat was produced by using SCNT.To investigate whether there are epigenetic differences between cloned and WT(wild type)goats,WGBS(whole-genome bisulfite sequencing)was used to measure the whole-genome methylation of these animals.Results:It is observed that the different m Cp G sites are mainly present in the intergenic and intronic regions between cloned and WT animals,and their CG-type methylation sites are strongly correlated.DMR(differentially methylated region)lengths are located around 1000 bp,mainly distributed in the exonic,intergenic and intronic functional domains.A total of 56 and 36 DMGs(differentially methylated genes)were identified by GO and KEGG databases,respectively.Functional annotation showed that DMGs were enriched in biological-process,cellularcomponent,molecular-function and other signaling pathways.A total of 10 identical genes related to growth and development were identified in GO and KEGG databases.Conclusion:The differences in methylation genes among the tested animals have been identified.A total of 10 DMGs associated with growth and development were identified between cloned and WT animals.The results indicate that the differential patterns of DNA methylation between the cloned and WT goats are probably caused by the SCNT.These novel observations will help us to further identify the unveiled mechanisms of somatic cell cloning technology,particularly in goats.
