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1.
Background: Vitellogenin(VTG) is a precursor of egg yolk proteins synthesized within the liver of oviparous vertebrates. Betaine is an important methyl donor that is reported to improve egg production of laying hens with an unclear mechanism. In the present study, we fed betaine-supplemented diet(0.5%) to laying hens for 4 wk and investigated its effect on VTGII expression in the liver.Results: Betaine did not affect chicken weight, but significantly(P 0.05) increased egg laying rate accompanied with a significant(P 0.05) increase in hepatic concentration and plasma level of VTGI. Plasma estrogen level did not change,but the hepatic expression of estrogen receptor α(ERα) mR NA was significantly(P 0.05) up-regulated. Betaine did not affect the protein content of ERα, but significantly(P 0.05) increased hepatic expression of glucocorticoid receptor(GR)at both mR NA and protein levels. Also, ERα/GR interaction tended to be enhanced in the liver nuclear lysates of betainesupplemented hens as determined by co-immunoprecipitation. Furthermore, dietary betaine supplementation significantly increased(P 0.05) the hepatic expression of methyl-transfer enzymes, such as BHMT, GNMT, and DNMT1,which was associated with higher SAM/SAH ratio and hypomethylation of GR promoter regions.Conclusions: Betaine activates hepatic VTGII expression in association with modified DNA methylation of GR gene promoter, GR expression and ERα/GR interaction. Activation of hepatic VTGII expression may contribute, at least partly, to improved egg production in betaine-supplemented hens.  相似文献   

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Background: Salmonella enterica serovar Enteritidis (SE), as a major cause of foodborn 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 108 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/I and 211.84 U/I respectively, and ALT values were 32.19 U/I and 24.55 U/I. 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. Ho  相似文献   

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Background:Skeletal muscle development,a long-term and complex process,is controlled by a set of the myogenic genes.Circular RNAs(circRNAs),a class of noncoding RNA,have been shown to regulate various biological processes.Recent studies indicate circRNAs may be involved in myogenesis,but the role and regulatory mechanism of circRNAs in myogenesis is largely unknown.In the present study,circCPE was firstly found to promote the bovine myoblast proliferation and inhibit cell apoptosis and differentiation by influencing the expression of FOXC1 in a miR138-mediated manner.And in vivo experiments revealed that overexpression of circCPE attenuates skeletal muscle regeneration.Results:We identified a novel circular RNA circCPE by analyzing circRNAs sequencing data of bovine muscle tissue.Sequencing verification,RNase R treatment and Actinomycin D treatment confirmed the circular nature of circCPE in bovine muscle.Functional assays showed that overexpression of circCPE could inhibit bovine myoblast apoptosis and differentiation,as well as facilitate cell proliferation.Moreover,in vivo experiments revealed that overexpression of circCPE attenuates skeletal muscle regeneration.In consideration of circRNA action as miRNAs sponge,we found that circCPE harbors miR-138 binding sites and absorbed miR-138.Mechanistically,the rescue experiments showed that the overexpression of circCPE can counteract the inhibitory effect of miR-138 on the cell proliferation and the accelerated effects on the differentiation and apoptosis.Subsequently,we found that circCPE sequester the inhibitory effect of miR-138 on FOXC1 so as to involve in myogenesis.Conclusions:Collectively,we constructed a novel circCPE/miR-138/FOXC1 regulatory network in bovine myogenesis,which further provide stronger evidence that circRNA involved in muscle development acting as miRNA sponge.  相似文献   

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Background: This study was to determine if feeding laying hens with defatted diatom microalgal biomass (DFA) from biofuel production affected their egg production and health status. Methods: Five replicates of 5 individually caged ISA Babcock White leghorn hens were fed 4 diets, including a corn-soybean meal control diet, a diet containing 7.5% DFA substituting for soybean meal, and diets containing 7.5% or 15% DFA substituting for corn and soybean meal. Body weights, feed intake, feed conversion ratio (FCR), rate of egg production, egg size, egg mass, and several characteristics of eggs were determined at 4 and 8 wk. Venous blood was sampled at 4 and 8 wk for measurement of 5 biomarkers of health. Results: The15% DFA diet decreased (P 〈 0.05) feed intake, egg production, and plasma uric acid concentrations as compared with the control diet, but increased (P 〈 0.05) egg albumen weight and height compared with the 7.5% DFA diets. The two levels of DFA produced dose-dependent (P 〈 0.05) changes in three color measures of egg yolk, without affecting four hen plasma biochemical indicators of health. Conclusions: Feeding laying hens with 7.5% DFA in the corn-soybean meal diet for 8 wk had no adverse effect on their health, egg production, or egg quality, but 15% inclusion reduced feed intake, egg production, and efficiency of feed utilization.  相似文献   

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This study examined the effects of various levels of dietary nonphytate phosphorus on laying performance and the expression patterns of phosphorus metabolism related genes in Dwarf pink-shell Jaying hens. A total of 405 28-week-old Dwarf pink-shell laying hens were fed the same corn-soybean basal meals but containing 0.20%, 0.25%, 0.30%, 0.35% or 0.40% nonphytate phosphorus. The results showed that feed intake, egg production, and average egg weights were quadratically correlated with dietary nonphytate phosphorus content (P 〈 0.05), and the highest egg production, feed intake and average egg weights were achieved when dietary nonphytate phosphorus was at 0.3% (P 〈 0.05). mRNA expression of intestinal sodium phosphorus co-transporter linearly decreased when dietary nonphytate phosphorus increased, mRNA and protein expression of intestinal calbindin and vitamin D receptor correlated quadratically with dietary nonphytate phosphorus, and the highest expression was found when dietary available phosphorus was at 0.2,5% to 0.3%. In conclusion, the ideal phosphorus requirement for Dwarf pink-shell layer hens is estimated to be 0.3% in a corn-soybean diet. With this level of phosphorus supplementation, calbindin and vitamin D receptor reached their highest expression.  相似文献   

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Background: Phosphorus is an essential nutrient to maintain poultry health and performance. The objective of this study was to evaluate the effect of dietary phosphorus levels on egg production, egg quality, bone health, immune responses of laying hens challenged with Escherichia coli lipopolysaccharide.Methods: Three hundred laying hens at 28 wk were randomly divided into 2 dietary treatments with 10 replicates of 15 birds. The wheat-soybean based diets contained either 0.12% or 0.4% non-phytate phosphorus(NPP). At 32 wk of age, all the birds of each dietary treatment were injected into the abdomen with 1.5 mg/kg body weight(BW) of either LPS or saline once a day at 24-h intervals for continuous 9 d. The performance of laying hens was evaluated for 9 d. The eggs after the fifth injection were collected to value the egg quality. Three hours after the first injection, blood was collected to measure serum metabolite and immune response associated parameters.Three hours after the fifth injection, the hens were euthanized to obtain tibia, cecal tonsils and jejunum.Results: Compared with saline-injected hens, LPS-injected hens had lower feed intake and egg production(P 0.05).Eggshell thickness, strength, albumin height and Haugh unit were significantly increased in LPS-injected hens compared with saline-injected hens(P 0.05). Furthermore, laying hens challenged with LPS had lower villious height/crypt depth ration than those received saline. Serum calcium, phosphorus and SOD activities significantly decreased in the LPS-injected hens compared with the control(P 0.05). LPS up-regulated expression of IL-1β, IL-6 and IL-10 in cecum, and serum concentration of MDA, IL-1β and IL-6(P 0.05), whereas 0.40% dietary non-phytate phosphorus supplementation significantly increased(P 0.05) villi height/crypt depth ratio, decreased(P 0.05) serum MDA and IFN-γ concentration compared with the 0.12% non-phytate phosphorus group.Conclusion: In summary, this study demonstrates that 0.40% dietary non-phytate phosphorus supplementation significantly increased calcium and phosphorus levels of eggshell, increased villi height/crypt depth ratio, decreased serum MDA and IFN-γ concentration compared with the 0.12% non-phytate phosphorus groups. The results indicate that high level of dietary non-phytate phosphorus exerts a potential effect in alleviating systemic inflammation of LPSchallenged laying hens.  相似文献   

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Barn Swallows(Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with human settlements.A tractable species for both individual-based and population-level studies, Barn Swallows are a prominent model system in evolutionary, ecological, and behavioral research. Here we review work on sexual selection and population divergence in this species complex, focusing on comparative studies among populations and subspecies.We summarize variation in the targets of mate choice and in the information conveyed by sexually selected traits, and conclude that the benefits advertised by different traits may vary geographically. Finally, we consider the role of sexual selection as a driver of population divergence in this widespread and phenotypically variable species complex.  相似文献   

8.
Cathelicidins are a major family of antimicrobial peptides present in vertebrate animals with potent microbicidal and immunomodulatory activities. Four cathelicidins, namely fowlicidins 1 to 3 and cathelicidin B1, have been identified in chickens. As a first step to understand their role in early innate host defense of chickens, we examined the tissue and developmental expression patterns of all four cathelicidins. Real-time PCR revealed an abundant expression of four cathelicidins throughout the gastrointestinal, respiratory, and urogenital tracts as well as in all primary and secondary immune organs of chickens. Fowlicidins 1 to 3 exhibited a similar tissue expression pattern with the highest expression in the bone marrow and lung, while cathelicidin B1 was synthesized most abundantly in the bursa of Fabricius. Additionally, a tissue-specific regulatory pattern was evident for all four cathelicidins during the first 28 days after hatching. The expression of fowlicidins 1 to 3 showed an age-dependent increase both in the cecal tonsil and lung, whereas all four cathelicidins were peaked in the bursa on day 4 after hatching, with a gradual decline by day 28. An abrupt augmentation in the expression of fowlicidins 1 to 3 was also observed in the cecum on day 28, while the highest expression of cathelicidin B1 was seen in both the lung and cecal tonsil on day 14. Collectively, the presence of cathelicidins in a broad range of tissues and their largely enhanced expression during development are suggestive of their potential important role in early host defense and disease resistance of chickens.  相似文献   

9.
Background: Sertoli cells(SCs) create a specialized environment to support and dictate spermatogenesis.MicroRNAs(miRNAs), a kind of ~ 22 nt small noncoding RNAs, have been reported to be highly abundant in mouse SCs and play critical roles in spermatogenesis. However, the miRNAs of porcine SCs remain largely unknown.Methods: We isolated porcine SCs and conducted small RNA sequencing. By comparing miRNAs in germ cells, we systematically analyzed the miRNA expression pattern of porcine SCs. We screened the highly enriched SC miRNAs and predicted their functions by Gene Ontology analysis. The dual luciferase assay was used to elucidate the regulation of tumor necrosis factor receptor(TNFR)-associated factor 3(TRAF3) by ssc-miR-149.Results: The analysis showed that 18 miRNAs were highly expressed in SCs and 15 miRNAs were highly expressed in germ cells. These miRNAs were predicted to mediate SC and germ cell functions. In addition, ssc-miR-149 played critical roles in SCs by targeting TRAF3.Conclusion: Our findings provide novel insights into the miRNA expression pattern and their regulatory roles of porcine SCs.  相似文献   

10.
The rapid growth of the world population since 1950 and the contribution matching the GDP and the income per capita has been seen in the increase competition for FDI of the past few years. Therefore, it is well-known that FDI can contribute to economic development not only by being a source of foreign capital, but also by providing employment, opportunities, increasing competition, and most importantly transferring skills and knowledge done by spillover effects.However, these positive effects are not automatic for host countries in the long run and depend largely on the policies taking in place. Having a closer look at the People′s Republic of China(PRC) and by examining how the policies in place have attracted FDI and looking to the contributions that foreign direct invest can make to the recipient country,showing the effects in industries that are economic pushers such as the mining industry can give us the general idea. Hence, FDI has contributed positively to Chinese economic development; there are challenges in order that the People′s Republic China can effectively continue benefitting from it at a larger extent.  相似文献   

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Background: Increasing evidence indicates that micro RNAs(mi RNAs) are involved in inflammatory response and immune regulation following pathogen invasion. The purpose of this study was to elucidate the roles played by Gallus gallus micro RNA-1306-5 p(gga-mi R-1306-5 p) in host responses against potential invasion by Salmonella enteritidis(SE) in chickens and the underlying mechanisms.Results: In present study, the expression levels of gga-mi R-1306-5 p were determined in both tissues and HD11 cells. The results showed that gga-mi R-1306-5 p was significantly increased following SE infection or lipopolysaccharide(LPS) stimulation. The dual luciferase reporter assay further validated that gga-mi R-1306-5 p targeted the Toll-interacting protein(Tollip), and thereby participated in the regulation of immune response against SE or LPS stimulation through binding with the 3′-untranslated region(3'UTR) of Tollip. Additionally, the expression of Tollip was significantly blocked by over-expressed gga-mi R-1306-5 p. The underlying mechanisms by which ggami R-1306-5 p modulated the production of pro-inflammatory cytokines were also investigated. Molecular biological assays demonstrated that overexpression of gga-mi R-1306-5 p promoted the production of pro-inflammatory mediators, including NF-κB, TNF-α, IL-6, and IL-1β, which produced effects similar to those of Tollip knockdown.Conclusions: Taken together, gga-mi R-1306-5 p induced by SE or LPS, regulates the immune response by inhibiting Tollip, which activates the production of inflammatory cytokines. This study has provided the first direct evidence that gga-mi R-1306-5 p targets Tollip, and is involved in the host response against SE.  相似文献   

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Background:Dietary essential oil(EO)supplementation can exert favorable effects on gut health in broilers.However,it is unknown whether EO could improve intestinal functions,consequently beneficial for egg performance and quality in late-phase laying hens.This study was aimed to investigate the potential effects of EO on production performance,egg quality,intestinal health and ileal microbiota of hens in the late phase of production.A total of 28860-week-old Hy-line Brown laying hens were randomly divided into 4 groups and fed a basal diet(control)or basal diets supplemented with oregano EO at 100,200 and 400 mg/kg(EO100,EO200 and EO400).Results:Dietary EO supplementation resulted in a quadratic decrease(P<0.05)in feed conversion ratio with lower(P<0.05)feed conversion ratio in EO200 group than the control during weeks 9–12 and 1–12 of the trial.Compared to the control,EO addition resulted in higher(P<0.05)eggshell thickness at the end of week.4,8 and 12 and higher(P<0.05)chymotrypsin activity.There was a quadratic elevation(P<0.05)in ileal chymotrypsin and lipase activity,along with a linear increase in villus height to crypt depth ratio.Quadratic declines(P<0.05)in mRNA expression of IL-1β,TNF-α,IFN-γ and TLR-4,concurrent with a linear and quadratic increase(P<0.05)in ZO-1 expression were identified in the ileum with EO addition.These favorable effects were maximized at medium dosage(200 mg/kg)of EO addition and intestinal microbial composition in the control and EO200 groups were assessed.Dietary EO addition increased(P<0.05)the abundances of Burkholderiales,Actinobacteria,Bifidobacteriales,Enterococcaceae and Bacillaceae,whereas decreased Shigella abundance in the ileum.Conclusions:Dietary EO addition could enhance digestive enzyme activity,improve gut morphology,epithelial barrier functions and modulate mucosal immune status by altering microbial composition,thus favoring feed efficiency and eggshell quality of late-phase laying hens.  相似文献   

15.
Missing genotypes are a common feature of high density SNP datasets obtained using SNP chip technology and this is likely to decrease the accuracy of genomic selection. This problem can be circumvented by imputing the missing genotypes with estimated genotypes. When implementing imputation, the criteria used for SNP data quality control and whether to perform imputation before or after data quality control need to consider. In this paper, we compared six strategies of imputation and quality control using different imputation methods, different quality control criteria and by changing the order of imputation and quality control, against a real dataset of milk production traits in Chinese Holstein cattle. The results demonstrated that, no matter what imputation method and quality control criteria were used, strategies with imputation before quality control performed better than strategies with imputation after quality control in terms of accuracy of genomic selection. The different imputation methods and quality control criteria did not significantly influence the accuracy of genomic selection. We concluded that performing imputation before quality control could increase the accuracy of genomic selection, especially when the rate of missing genotypes is high and the reference population is small.  相似文献   

16.
PR-39 is a porcine antimicrobial peptide that plays an important role in the innate defense mechanism.We produced monoclonal antibodies(MAbs)against PR-39 by fusing mouse myeloma cells with lymph node cells from BALB/c mice immunized with the reactive site sequence PR-11 of PR-39.Furthermore,we investigated the effect of lactoferrin on PR-39 gene levels and peptide concentrations in cultural supernatants of bone marrow granulocytes by RT-PCR and the competitive inhibition ELISA method established in this study.Two hybridomas 3H5 and 5H7 were selected for developing ascites and contained MAbs against PR-11,which were used for screening the specificity to PR-39 by competitive inhibition ELISA.We found that MAbs were successfully produced against PR-11 and the MAbs had a strong reaction with PR-39 excreted by porcine marrow granulocytes.The ascites had a relatively high titer and the purified MAbs were determined as IgG1.Incubation with 10 or 100 μg/mL lactoferrin significantly increased(P0.05)PR-39 mRNA levels in bone marrow granulocytes after 3 h and 6 h,but 1000 μg/mL lactoferrin reduced(P0.05)PR-39 mRNA expression after 3 h and 6 h compared with control(no lactoferrin added).The relative concentrations of PR-39 in supernatant secreted by marrow granulocytes were significantly increased by 1000 μg/mL lactoferrin after both 3 h and 6 h.These findings suggest a regulatory role of lactoferrin for the antimicrobial peptide PR-39 in marrow cells in vitro.It is possible that the regulation of antimicrobial peptide PR-39 expression may be one of the protective mechanisms of lactoferrin in pigs.  相似文献   

17.
We will try to demonstrate, through the display of the various advertising creation strategies and their evolution, how the advertising communication passed from of a vision or a strategy focused on the product, to a vision focused on the brand. The first advertising strategy that was applied by advertising agencies is the"Unique Selling Proposition";it focused only on the product advantages and its philosophy dominated the advertising world, throughout its various evolutions, till the nineties but this is without counting the introduction of the new advertising strategies that brought a more brand oriented philosophy to the ground.  相似文献   

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Background: Resveratrol, an important phyto-antioxidant commonly found in grapes, mulberry, and other plants,has a variety of functions including anti-aging, anti-cancer and anti-inflammatory activities. In the current study, we investigated the beneficial effects of resveratrol on in vitro porcine oocyte maturation under heat stress(HS). The effect of resveratrol, melatonin and their combination on alleviating HS was compared according to the maturation rate of oocytes and the development competence of embryos after parthenogenetic activation(PA).Results: Supplementation with resveratrol(2.0 μmol/L) not only improved the nuclear maturation but also raised the blastocyst rate of porcine embryos' PA from oocytes that underwent HS by increasing their glutathione(GSH)level, reducing reactive oxygen species(ROS) and up-regulating the expression of Sirtuin 1(SIRT1). It was also found that melatonin(10~(-7)mol/L) and the combination of resveratrol(2.0 μmol/L) plus melatonin(10~(-7)mol/L) exhibited more potent effects than resveratrol alone regarding their protective activities on oocyte maturation under HS.Conclusions: This study compared the efficiencies of resveratrol, melatonin and their combination for protecting porcine oocytes from heat stress. The mechanisms are attributed to the fact that each treatment may have different ability to regulate the synthesis of steroid hormones and the expression of mature related genes.  相似文献   

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