Transgenerational effects of certain nutrients such as essential fatty acids are gaining increased attention in the field of human medicine and animal sciences as a new tool to improve health and animal performance du...Transgenerational effects of certain nutrients such as essential fatty acids are gaining increased attention in the field of human medicine and animal sciences as a new tool to improve health and animal performance during perinatal life.Omega-3(n-3)and omega-6(n-6)fatty acids are denoted by the position of the first double bond from methyl end of the hydrocarbon chain.Alpha-linolenic acid(18:3 n-3)and linoleic acid(18:2 n-6)are essential n-3 and n-6 fatty acids and cannot be synthesized by the vertebrates including chickens.Alpha-linolenic acid and linoleic acid are the parent fatty acids of long chain(>20–22C)n-3 and n-6 polyunsaturated fatty acids(PUFA)such as eicosapentaenoic acid(20:5 n-3,EPA),docosapentaenoic acid(22:5 n-3/or 22:5 n-6,DPA),docosahexaenoic acid(22:6 n-3,DHA)and arachidonic acid(20:4 n-6).As components of cell membrane phospholipids,PUFA serves as precursors of eicosa-noids,act as ligands for membrane receptors and transcription factors that regulate gene expression and are pivotal for normal chick growth and development.Considering the role of egg lipids as the sole source of essential fatty acids to the hatchling,dietary deficiencies or inadequate in ovo supply may have repercussions in tissue PUFA incorpora-tion,lipid metabolism,chick growth and development during pre and early post-hatch period.This review focus on studies showing how maternal dietary n-3 or n-6 fatty acids can lead to remodeling of long chain n-3 and n-6 PUFA in the hatching egg and progeny chick tissue phospholipid molecular species and its impact on chick growth and PUFA metabolism during early life.展开更多
Hatchery contamination can result in ingested or inhaled microbes that may modify colonization of the intestinal and respiratory tract, with potential to influence early growth, inflammation, and overall health. Six e...Hatchery contamination can result in ingested or inhaled microbes that may modify colonization of the intestinal and respiratory tract, with potential to influence early growth, inflammation, and overall health. Six experiments were completed to compare chick quality, inflammation, and health between two hatcheries (H1 and H2). On embryonic d0, 45 eggs from the same breeder flock were set at each hatchery. On d0, length, abdominal height, navel and leg abnormalities, and self-righting were measured for 36 chicks/hatchery, yolk sacs were weighed, and crop/cloaca swabs were cultured from 12 chicks/hatchery. On d7, mid-ileum and ceca were cultured from 12 chicks/hatchery. On d0 and d7, body weight (BW) and intestinal weight were measured, lung/air sac swabs and liver were cultured, and liver and air sacs were scored for health. Blood was collected on d0 and d7 for serum alpha-1-acid glycoprotein concentrations in Exp 1 and 2. Data was analyzed using Student’s t-test or χ<sup>2</sup>, significance p < 0.05. On d0, BW, length, yolk free BW, and intestinal weight were greater for H2 chicks (p < 0.05). Liver bacterial recovery was decreased in H2 on d0 (p < 0.05) and there were fewer average leg and righting abnormalities in H2 (p < 0.05). Decreased lactase positive Enterobacteriaceae were noted in H2 in crop/cloaca and lung/air sac swabs (p < 0.05), and of alpha and beta hemolysis in crop/cloaca swabs, and alpha and gamma hemolysis in lung/air sac swabs (p < 0.05) on d0. By d7, only alpha hemolytic bacteria were increased in lung/air sac swabs of H2. Based on factors measured, chicks from H2 showed favorable microbial colonization, starting quality, and improved health on d0. While not sustained through d7, differences in d0 microbial recovery may have shifted microbial development and potentially influenced immune response development. These experiments elucidated the importance of hatchery environment on early chick quality, microbial colonization, overall inflammation, and chick health.展开更多
[Objectives]The paper was to study the effects of combined application of nonreplicating Toxoplasma uracil auxotrophs(NRTUAs)and Agaricus blazei Murill polysaccharide(ABP)on growth and humoral immunity of chicks.[Meth...[Objectives]The paper was to study the effects of combined application of nonreplicating Toxoplasma uracil auxotrophs(NRTUAs)and Agaricus blazei Murill polysaccharide(ABP)on growth and humoral immunity of chicks.[Methods]A total of 120 one-day old female Hyline brown laying hens were randomly divided into 4 groups,30 hens for each group.The chicks in group 1 were subcutaneously injected with NRTUAs and fed on the diet containing with ABP;the chicks in group 2 were subcutaneously injected with NRTUAs;the chicks in group 3 were subcutaneously injected with equal volume of PBS,and fed on the diet containing with ABP;the chicks in group 4 were subcutaneously injected with equal volume of PBS.The body weight of chicks in each group was counted at the 21^(st),42^(nd),84^(th)and 112^(th)week.During this period,blood samples were collected from chicks in each group at 0,7,14,21,28 and 35 d post immunization against Newcastle disease(ND),and serum was separated to detect the antibody titer of ND.[Results]The combined application of NRTUAs and ABP had no effect on growth of chicks,but promoted the humoral immune response of chicks,significantly improved the ND antibody level of chicks,and could maintain high levels of antibodies in the body for a long time.[Conclusions]The study lays a theoretical foundation for further developing the clinical application of NRTUAs and ABP.展开更多
[Objective] This study aimed to investigate the distribution law of different goblet cells in the intestinal tracts of African ostrich chicks. [Method] Alcian blue/pe- riodic acid-schiff reaction （AB/PAS） was adopte...[Objective] This study aimed to investigate the distribution law of different goblet cells in the intestinal tracts of African ostrich chicks. [Method] Alcian blue/pe- riodic acid-schiff reaction （AB/PAS） was adopted to observe and analyze the types and distribution of goblet cells in the intestinal tracts of ostrich chicks. Acid mu- copolysaccharide could be stained blue with alcian blue （AB）, and neutral mu- copolysaccharide could be stained red with periodic acid-schiff reagent （PAS）. [Result] According to AB/PAS results, goblet cells in the intestinal tracts were divided in- to four types： TypeⅠ was pure red, with AB negative result and PAS positive result containing neutral mucoitin; type Ⅱ was pure blue, with AB positive result and PAS negative result containing acidic mucoitin; type Ⅲ was purple reddish, with PAS posi- tive result greater than AB; typeⅣ was purple blue, with AB positive result greater than PAS. Large quantities of goblet cells were found in the intestinal tracts of os- trich chicks, mostly type III and IV.The quantities of goblet cells were decreased gradually in the duodenum, jejunum and ileum, while the quantities were increased in the cecum, colon and rectum. The goblet cells in the large intestine are more than that in the small intestine. The most quantities of goblet cells were contained in rectum. [Conclusion] These results indicate that the distribution of goblet cells is closely related with the structure and function of intestinal tracts. The mucus secret- ed by the goblet Cells plays a series of important roles in the digestion and mucosal immunization.展开更多
[Objective] This study aimed to investigate the differences in morphological structure of tibias between sick and normal ostrich chicks. [Method] Normal and sick ostrich chicks aged 90 days were used in this research ...[Objective] This study aimed to investigate the differences in morphological structure of tibias between sick and normal ostrich chicks. [Method] Normal and sick ostrich chicks aged 90 days were used in this research for bone mineral density determination, bone demineralization paraffin section preparation （HE staining）, bone abrasive disc preparation and scanning electron microscopy （SEM） observation, to analyze the differences in microstructure and ultrastructure of tibias between sick ostrich chicks and normal ones. [Result] Bone mineral density of ostrich chicks suffering from leg disease was much lower than that of the normal ones. Compared with normal tibias, less trabeculae were observed in sick tibias, which were attenuated and began to disappear. In addition, trabeculae micro-fracture could be observed under scanning electron microscope; resorption pits on bone slices formed by osteoclast could be observed under scanning electronic microscope. [Conclusion] These results indicate that the sick tibias all have lower bone density and trabeculae microfracture phenomenon in tibias with different diseases, which might be resulted from osteoporosis.展开更多
In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing ...In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing medical antibodies has been widely used in the production practice. However, there are few studies about the effect of the different injection site and dosage on chicken embryos. The aim of this study was to explore the effects of different injection sites and dosages on chicken embryo hatching rate and development, so as to provide a basis for further studies using the chicken embryo model. Freshly laid eggs （Rugao yellow chicken） were injected with different doses of saline at the tip, equatorial plane and the blunt end of the egg shell, respectively. Egg hatching rate was recorded and compared among injection sites and different doses. A trypan blue stain was also injected at the aforementioned sites and the growth of chicken embryos was observed. The SPSS （statistical package for the social science） software was used to analyze the relationship between the chicken eggs hatching rate and the different injection sites or the different dosages. The experimental results showed that there were significant differences on egg hatching rates among the different injection sites and doses （P〈0.05）. The hatchability of the blunt end injection group was significantly higher than that of the other two sites. The egg hatching rate decreased with increased saline doses. The egg hatching rate of the 100 pL saline injection group was higher than the 200 and 300 μL dosage groups. Ultimately, we suggest that the optimal chicken embryo injection process is during early development, at the blunt end site with a dose less than 100 μL to minimize damage to the egg.展开更多
Background:Prenatal nutrition is crucial for embryonic development and neonatal growth,and has the potential to be a main determinant of life-long health.In the present study,we used a layer chick model to investigate...Background:Prenatal nutrition is crucial for embryonic development and neonatal growth,and has the potential to be a main determinant of life-long health.In the present study,we used a layer chick model to investigate the effects of in ovo feeding(IOF)of L-arginine(Arg)on growth,intestinal development,intestinal microbiota and metabolism.The treatments included the non-injected control,saline-injected control,and saline containing 2,6,or 10 mg Arg groups.Results:IOF Arg increased early intestinal index and villus height,and enhanced uptake of residual yolk lipid,contributing to subsequent improvement in the early growth performance of chicks.Prenatal Arg supplementation also increased the early microbialα-diversity,the relative abundance of Lactobacillales and Clostridiales,and decreased the relative abundance of Proteobacteria of cecum in chicks.Furthermore,the shift of cecal microbiota composition and the colonization of potential probiotics were accelerated by IOF of Arg.Simultaneously,metabolomics showed that metabolisms of galactose,taurine-conjugated bile acids and lipids were modulated to direct more energy and nutrients towards rapid growth of intestine at the beginning of post-hatch when embryos received IOF of Arg.Conclusions:Prenatal Arg supplementation showed beneficial effects on the early intestinal development,cecal microbiota and host metabolism of layer chicks,contributing to subsequent improvement in the early growth performance.These findings provide new insight into the role of IOF of Arg in the establishment of the gut microbiota of newly-hatched layer chicks,and can expand our fundamental knowledge about prenatal nutrition,early bacterial colonization and intestinal development in neonate.展开更多
A study was under taken to investigate the effect of dietary supplementations of humic acid and esterified glucomannan) on broiler performance and the morphological measurements of small intestine. Two hundred and ten...A study was under taken to investigate the effect of dietary supplementations of humic acid and esterified glucomannan) on broiler performance and the morphological measurements of small intestine. Two hundred and ten day old broiler chicks were weighed and randomly assigned to seven treatment groups in triplicate. The dietary treatments included T1) control (basal diet without any additives), T2) basal diets supplemented with 0.1% humic acid, T3) basal diets supplemented with 0.2% humic acid, T4) basal diets supplemented with 0.3% humic acid, T5) basal diets supplemented with 0.1% esterified glucomannan, T6) basal diets supplemented with 0.2% esterified glucomannan and T7) basal diets supplemented with 0.3% esterified glucomannan. Different parameters including body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and morphology of small intestine were evaluated during six weeks of experimental period. According to the results, at the end of experimental period, the highest average BWG were recorded in T4 group (fed with 0.3% humic acid), compared to control (T1) and other experimental groups (p < 0.05). Where as, the highest body weight gain were observed during starter period in treatment 7 (fed with 0.3% esterified glucomannan) as compare to other experimental groups (p < 0.05). Statistically, feed intake remained unaffected during the experimental period in all the treatment groups. However, the lowest and the highest feed intake were observed numerically within treatments T4 and T1 with 4229.70 g and 4362.30 g, respectively. Addition of dietary supplements used in the study appeared to have significant effect on the morphology of the small intestine (jejunum mucosal development) of the broilers in different treatment groups. Compared to control group, the inclusion of either humic acid or esterified glucomannon decreased (p < 0.01) the crypt depth and increased villus height respectively (p < 0.05). More ever, the diet supplements with humic acid 0.3% (T4) decreased crypt depth compared to esterified glucomannan and control. The dietary supplementations resulted in an increase in the villus height of intestinal mucosa of broilers. The increase in the villus height was associated with improvement of growth performance for both humic acid and esterified glucomannan. Based on our results it appeared that humic acid and esterified glucomannan can be used as a growth promoter in broiler diets and they can improve the gut health too.展开更多
Aim: This study was designed to investigate the effect of busulfan treatment on the proliferation of chicken primordialgerm cells (PGCs) in vivo, focusing on the preferential settlement of PGCs onto the germinal ridge...Aim: This study was designed to investigate the effect of busulfan treatment on the proliferation of chicken primordialgerm cells (PGCs) in vivo, focusing on the preferential settlement of PGCs onto the germinal ridges of chicken em-bryos. Methods: Busulfan (250 ng/egg) was injected into the egg white of freshly oviposited fertilized eggs, whichwere then incubated. Embryonic development and viability were examined, and exogenous PGCs collected from embry-onic blood vessels were injected into the germinal crescent region of recipient embryos. The number of PGCs residedonto germinal ridges of the right and left sides were compared. Results: Busulfan had a slight harmful effect on theembryo viability and the PGCs proliferation. The number of PGCs resided onto the left side of germinal ridges wasslightly higher as compared with the right side. Conclusion: Busulfan suppressed the viability of embryos and the pro-liferation of endogenous PGCs in the recipient embryos. However, the number of exogenous PGCs proliferated washigher in embryos treated with busulfan than those without busulfan. Data also suggest the possibility of a preferentialresidence of PGCs toward the left side of the germinal crescent region as compared with the fight, which may be due toa more advanced functional development of the left gonad than the right. (Asian J Androl 1999 Dec; 1: 187-190)展开更多
Aim:To examine the transfection of exogenous genes into chick embryos,applying the characteristics of avianleukosis vires(ALV)-induced chicken B cell line DT40 to the production of chimeric birds.Methods:The DT40cells...Aim:To examine the transfection of exogenous genes into chick embryos,applying the characteristics of avianleukosis vires(ALV)-induced chicken B cell line DT40 to the production of chimeric birds.Methods:The DT40cells incorporated with exogenous gene(lacZ constructs encoding Escherichia coliβ-galactosidase:β-gal)were intro-duced into chick embryos by the injection of cells into stage X blastoderm.Manipulated eggs were incubated for 3(trial1)or 6(trial 2)days,and the expression of lacZ DNA was detected by a histochemical staining method ofβ-galactosi-dase and polymerase chain reaction(PCR)analysis.Results:The survival rates of the manipulated embryos incu-bated for 3 days(stage 18-20:trial 1)and 6 days(stage 28,30:trial 2)were about 42%and 38%,respectively.The expression rates of the lacZ gene in the embryos in the trials 1 and 2 were about 60%and 23%,respectively,forthe survived embryos.Conclusion:The rate of embryonic viability and expression rate of introduced genes were notso high,but it suggested the possibility of utilizing the DT40 cells as a vector for carrying exogenous genes into chickembryos.展开更多
A new selenium source, Nano red elemental selenium (Nano-Se) was used to study the effect on the GPx activity of broiler chick kidney cells (BCKC) in vitro, Sodium selenite (Na_ 2 SeO_ 3 ) and seleno-1-methionine (S...A new selenium source, Nano red elemental selenium (Nano-Se) was used to study the effect on the GPx activity of broiler chick kidney cells (BCKC) in vitro, Sodium selenite (Na_ 2 SeO_ 3 ) and seleno-1-methionine (Se-Met) were used as the controls. The results showed that the effects of three kinds of Se forms on the GPx activity of BCKC were accordant(p>0.05) compared with each other at 0.01,0.05 and 0.10 μmol/L Se concentrations treatments. In the range of 0.00-0.10 μmol/L Se concentrations, the GPx activity increased with elevation of Se concentrations in medium. For the three kinds of Se forms, the GPx activity reached the climax at 0.10 μmol/L Se concentration. At 0.20 and 0.30 μmol/L Se concentrations, the influnces of three kinds of Se forms were not accordant with one another. For Nano-Se, the GPx activity at 0.20 and 0.30 μmol/L Se concentrations remained the same as that at 0.10 μmol/L Se concentration treatment. For Se-Met, the GPx activity at 0.20 μmol/L Se concentration treatment remained the same with 0.10 μmol/L treatment; the GPx activity at 0.30 μmol/L Se concentration treatment was declined significantly(p<0.05) compared with 0.10 or 0.20 μmol/L treatment. For Na_ 2 SeO_ 3 , the GPx activity falled gradually with Se concentration increasing from 0.10 μmol/L to 0.30 μmol/L, and at 0.30 μmol/L Se concentration treatment, the GPx activity was less than the original of BCKC. The results implicated, on the GPx activity of BCKC in vitro, the ranking of width range of the most suitable Se concentration for nutrition curve of the three Se formes is Nano-Se>Se-Met>Na_ 2 SeO_ 3 .展开更多
Feed intake control is vital to ensuring optimal nutrition and achieving full potential for growth and development in poultry. The aim of the present study was to investigate the effects of L-leucine, L-glutamate, L-t...Feed intake control is vital to ensuring optimal nutrition and achieving full potential for growth and development in poultry. The aim of the present study was to investigate the effects of L-leucine, L-glutamate, L-tryptophan and L-arginine on feed intake and the mRNA expression levels of hypothalamic Neuropeptide involved in feed intake regulation in broiler chicks. Leucine, glutamate, tryptophan or arginine was intra-cerebroventricularly （ICV） administrated to 4d-old broiler chicks respectively and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of Neuropeptide Y （NPY）, agouti related protein （AgRP）, pro-opiomelanocortin （POMC）, melanocortin receptor 4 （MC4R） and corticotrophin releasing factor （CRF）. Our results showed that ICV administration of L-leucine （0.15 or 1.5 μmol） significantly （P〈0.05） increased feed intake up to 2 h post-administration period and elevated both hypothalamic NPY and AgRP mRNA expression levels. In contrast, ICV administration of L-glutamate （1.6 μmol） significantly （P 〈 0.05） decreased feed intake 0.25, 0.5 and 2 h post-injection, and increased hypothalamic CRF and MC4R mRNA expression levels. Meanwhile, both L-tryptophan （10 or 100 μg） and L-arginine （20 or 200 μg） had no significant effect on feed intake. These findings suggested that L-leucine and L-glutamate could act within the hypothalamus to influence food intake, and that both orexigenic and anorexigenic Neuropeptide genes might contribute directly to these effects.展开更多
[Objective] The paper was to investigate the clinical effects of Nvhuang Fuzheng oral liquid on immunity enhancement,disease resistance and growth promotion of chicks. [Method] In the test,3-day-old Daninghe chicks we...[Objective] The paper was to investigate the clinical effects of Nvhuang Fuzheng oral liquid on immunity enhancement,disease resistance and growth promotion of chicks. [Method] In the test,3-day-old Daninghe chicks were divided into normal control group,Nvhuang Fuzheng oral liquid group and positive control group. Chicks were administrated with drugs for 7 d before immunization. After vaccination,chicks were observed for 4 weeks,to statistically count the incidence state of chicks. Effects of Nvhuang Fuzheng oral liquid on growth performance,serum immunoglobulin,cytokine and infectious bursal disease virus( IBDV)antibody were studied. [Result] Compared to normal control group,Nvhuang Fuzheng oral liquid significantly improved the weight of chicks and reduced the feed gain ratio( P < 0. 05); significantly reduced the morbidity and mortality and increased the survival rate of chicks( P < 0. 05); continuously increased IgG,IgM and IL-2 content significantly in the serum of chicks( P < 0. 05); extremely improved IFN-γ content in the serum at 7 d post drug administration( P < 0. 01). After vaccination of IBDV vaccine for 1 and 2 weeks,Nvhuang Fuzheng oral liquid significantly improved IBDV antibody titer and positive rate of chicks compared to normal control group( P < 0. 05); at 3 weeks post immunization,the antibody positive rate reached 100%. [Conclusion]Nvhuang Fuzheng oral liquid improved immunoglobulin and cytokine levels of chicks,enhanced the immunity and reduced the occurrence of diseases( the morbidity was reduced by 15% and the mortality was reduced by 30%),enhanced disease-resistant ability and promoted the growth of chicks. Meantime,it improved the immune effect of IBDV vaccine.展开更多
In this experiment, 540 male and female chicks of 1-day-age were selected respectively and reared separately. 3×3 factorial experiment was designed. Gushi chicks were fed with nine diets under different metaboliz...In this experiment, 540 male and female chicks of 1-day-age were selected respectively and reared separately. 3×3 factorial experiment was designed. Gushi chicks were fed with nine diets under different metabolizable energy (ME) and crude protein (CP). Effects of different diets on the performances and carcass ingredients of 0-to 4-week-age Gushi chicks were studied by rearing, comparative slaughter and metabolism experiments. Based on the results of three experiments, ME intake per kilogram metabolic weight was regarded as dependent variable (Y) ,and its corresponding net energy (NE) deposition per kilogram metabolic weight was regarded as independent variable (X) , respectively. Lineal regressive analysis was made according to the mathematic model: Y=a+bX. Maintenance ME( MEm) and the converted coefficient from net energy for gain( NEg) to ME for gain( MEg) were found out, then ME requirement was divided into MEm+ MEg, which is ME=359.14 W0.75+ 10.47△W; CP intake and corresponding metabolic weight were regarded as dependent variable and independent variable respectively, and then regressive analysis was made. The result was CP=0. 57 + 8. 21 W0.7S. Consequently, average daily gain (ADG), average daily feed intake and metabolic weight were put into the regressive equations, and then ME and CP requirements for 0- to 4-week-age Gushi chicks were obtained, 12.38 MJ kg-1 and 20.13%, respectively, the ratio of CP to ME was 16. 26 g MJ-1.展开更多
Aim： To assess whether exogenous estradiol has any effect on migration of primordial germ cells （PGCs） in the chick. Methods： Fertilized eggs were treated with 17beta-estradiol （E2） （80 lag/egg） at stage X （d...Aim： To assess whether exogenous estradiol has any effect on migration of primordial germ cells （PGCs） in the chick. Methods： Fertilized eggs were treated with 17beta-estradiol （E2） （80 lag/egg） at stage X （day 0 of incubation）, stages 8-10 （incubation 30 h） and 13-15 （incubation 55 h）. Controls received vehicle （emulsion） only. Changes in PGC number were measured on different days according to developmental stages. Results： In male right gonads, but not in female left gonads, at stages 28-30 （incubation 132 h） significant decreases in the mean number of PGCs aggregating were observed compared with the controls （P 〈 0.05） while the total PGC number in the right and left gonads at each stage did not change （P 〉 0.05）. Conclusion： The present study provides evidence that E2 has significant effects on the localization of PGCs in male right, but not female left, gonads of chicken embryos at stages 28-30, compared with controls. （Asian J Andro12008 Mar; 10： 243-248）展开更多
Objective: We established a transplantation tumor model of human osteosarcoma in chick embryo, studied its morphological and biological characteristics, and observed its dynamic process of angiogenesis induction so th...Objective: We established a transplantation tumor model of human osteosarcoma in chick embryo, studied its morphological and biological characteristics, and observed its dynamic process of angiogenesis induction so that a simple and practical model can be provided for studying osteosarcoma. Methods: Human osteosarcoma cells at different concentrations were inoculated in chorioallantoic membrane (CAM) of chick embryos at different embryonic ages to observe the factors affecting the survival of the transplanted osteosarcoma in chick embryo, growth characteristics of the transplantation tumor, and the morphological characteristics and biological characteristics of the transplantation tumor. Results: The transplantation tumor model of human osteosarcoma in chick embryo was successfully established. It was found that the transplantation tumor was easy to grow and it showed strong angiogenesis-inducing effects. Under the light microscope, the transplantation tumor showed a similar tissue structure to human osteosarcoma. Conclusion: It is feasible to establish a transplantation tumor model of human osteosarcoma in chick embryo. The model can be easily duplicated with a simple operation, which provides a useful animal model for studying osteosarcoma.展开更多
In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos wa...In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos was investigated. The hypothesis that Mn supplementation would enhance the expression of MnSOD in cultured primary myocardial cells of chick embryos was tested. Eggs collected from Mn-depleted Arbor Acres laying breeder hens were incubated for 10 days and then myocardial cells were isolated and cultivated for 8 days. The embryonic myocardial cells on day 6 were treated with Mn in the cell culture medium at different time points when the proportion of cells showing spontaneous contraction was over 95% after the 3-day primary culture. A completely randomized design involving a 3 Mn levels（0, 0.5 and 1.0 mmol L^（-1））×3 incubation time points（12, 24 and 48 h） factorial arrangement of treatments（n=6） was used in the current experiment. The results showed that MnSOD activity and m RNA expression level were induced by Mn and increased with incubation time, which supported the hypothesis that Mn would enhance the expression of the MnSOD gene, and thus might protect myocardial cells from oxidative stress during the chick embryonic development.展开更多
Members of the basic helix-loop-helix （bHLH） gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer （FRET） is used to monitor b...Members of the basic helix-loop-helix （bHLH） gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer （FRET） is used to monitor bHLH protein-protein interactions under various physiological conditions. Tissue-specific bHLH activators, NeuroD 1, Mash 1, Neurogenin 1 （Ngn 1）, Neurogenin2 （Ngn2）, and ubiquitous expressed E47 protein are tagged with enhanced yellow fluorescence protein （EYFP） and enhanced cyan fluorescence protein （ECFP）, respectively. The subcellular localization and mobility ofbHLH fusion proteins are examined in HEK293 cells. By transient transfection and in ovo electroporation, four pairs of tissue-specific bHLH activators and E47 protein are over-expressed in HEK293 cells and developing chick embryo neural tube. With the acceptor photobleaching method, FRET could be detected between these bHLH protein pairs in the nuclei of transfected cells and developing neural tubes. Mashl/E47 and Ngn2/E47 FRET pairs show higher FRET efficiencies in the medial and the lateral half of chick embryo neural tube, respectively. It suggests that these bHLH protein pairs formed functional DNA-protein complexes with regulatory elements of their downstream target genes in the specific regions. This work will help one understand the behaviours of bHLH factors in vivo.展开更多
In the present study, Pleurotus eryngii residue was added into conventional feed of Chai chicks and meat-type ducks at different ratios to measure its effects on the production performance of chicks and ducks. The res...In the present study, Pleurotus eryngii residue was added into conventional feed of Chai chicks and meat-type ducks at different ratios to measure its effects on the production performance of chicks and ducks. The results revealed that the growth performance of chicks and ducks was the best when 20% Pleurotus eryngii residue was added into the feed. Under such condition, the daily weight gain of 8 - 11 and 12 - 15-week-old Chai chicks was increased by 6.8% and 13.5%, and that of 8 - 11 and 12 - 15-week-old ducks was increased by 11.5% and 19.3%, respectively.展开更多
基金Supported in part by the National Research Initiative of the USDA Cooperative State Research,Education and Extension Service,grant number 2004–35204-14654Oregon State University Experiment Station Hatch fund,Oregon State University Animal Health Fund.
文摘Transgenerational effects of certain nutrients such as essential fatty acids are gaining increased attention in the field of human medicine and animal sciences as a new tool to improve health and animal performance during perinatal life.Omega-3(n-3)and omega-6(n-6)fatty acids are denoted by the position of the first double bond from methyl end of the hydrocarbon chain.Alpha-linolenic acid(18:3 n-3)and linoleic acid(18:2 n-6)are essential n-3 and n-6 fatty acids and cannot be synthesized by the vertebrates including chickens.Alpha-linolenic acid and linoleic acid are the parent fatty acids of long chain(>20–22C)n-3 and n-6 polyunsaturated fatty acids(PUFA)such as eicosapentaenoic acid(20:5 n-3,EPA),docosapentaenoic acid(22:5 n-3/or 22:5 n-6,DPA),docosahexaenoic acid(22:6 n-3,DHA)and arachidonic acid(20:4 n-6).As components of cell membrane phospholipids,PUFA serves as precursors of eicosa-noids,act as ligands for membrane receptors and transcription factors that regulate gene expression and are pivotal for normal chick growth and development.Considering the role of egg lipids as the sole source of essential fatty acids to the hatchling,dietary deficiencies or inadequate in ovo supply may have repercussions in tissue PUFA incorpora-tion,lipid metabolism,chick growth and development during pre and early post-hatch period.This review focus on studies showing how maternal dietary n-3 or n-6 fatty acids can lead to remodeling of long chain n-3 and n-6 PUFA in the hatching egg and progeny chick tissue phospholipid molecular species and its impact on chick growth and PUFA metabolism during early life.
文摘Hatchery contamination can result in ingested or inhaled microbes that may modify colonization of the intestinal and respiratory tract, with potential to influence early growth, inflammation, and overall health. Six experiments were completed to compare chick quality, inflammation, and health between two hatcheries (H1 and H2). On embryonic d0, 45 eggs from the same breeder flock were set at each hatchery. On d0, length, abdominal height, navel and leg abnormalities, and self-righting were measured for 36 chicks/hatchery, yolk sacs were weighed, and crop/cloaca swabs were cultured from 12 chicks/hatchery. On d7, mid-ileum and ceca were cultured from 12 chicks/hatchery. On d0 and d7, body weight (BW) and intestinal weight were measured, lung/air sac swabs and liver were cultured, and liver and air sacs were scored for health. Blood was collected on d0 and d7 for serum alpha-1-acid glycoprotein concentrations in Exp 1 and 2. Data was analyzed using Student’s t-test or χ<sup>2</sup>, significance p < 0.05. On d0, BW, length, yolk free BW, and intestinal weight were greater for H2 chicks (p < 0.05). Liver bacterial recovery was decreased in H2 on d0 (p < 0.05) and there were fewer average leg and righting abnormalities in H2 (p < 0.05). Decreased lactase positive Enterobacteriaceae were noted in H2 in crop/cloaca and lung/air sac swabs (p < 0.05), and of alpha and beta hemolysis in crop/cloaca swabs, and alpha and gamma hemolysis in lung/air sac swabs (p < 0.05) on d0. By d7, only alpha hemolytic bacteria were increased in lung/air sac swabs of H2. Based on factors measured, chicks from H2 showed favorable microbial colonization, starting quality, and improved health on d0. While not sustained through d7, differences in d0 microbial recovery may have shifted microbial development and potentially influenced immune response development. These experiments elucidated the importance of hatchery environment on early chick quality, microbial colonization, overall inflammation, and chick health.
基金Supported by National Natural Science Foundation of China(31902277)。
文摘[Objectives]The paper was to study the effects of combined application of nonreplicating Toxoplasma uracil auxotrophs(NRTUAs)and Agaricus blazei Murill polysaccharide(ABP)on growth and humoral immunity of chicks.[Methods]A total of 120 one-day old female Hyline brown laying hens were randomly divided into 4 groups,30 hens for each group.The chicks in group 1 were subcutaneously injected with NRTUAs and fed on the diet containing with ABP;the chicks in group 2 were subcutaneously injected with NRTUAs;the chicks in group 3 were subcutaneously injected with equal volume of PBS,and fed on the diet containing with ABP;the chicks in group 4 were subcutaneously injected with equal volume of PBS.The body weight of chicks in each group was counted at the 21^(st),42^(nd),84^(th)and 112^(th)week.During this period,blood samples were collected from chicks in each group at 0,7,14,21,28 and 35 d post immunization against Newcastle disease(ND),and serum was separated to detect the antibody titer of ND.[Results]The combined application of NRTUAs and ABP had no effect on growth of chicks,but promoted the humoral immune response of chicks,significantly improved the ND antibody level of chicks,and could maintain high levels of antibodies in the body for a long time.[Conclusions]The study lays a theoretical foundation for further developing the clinical application of NRTUAs and ABP.
基金Supported by National Natural Science Foundation of China (30972152)Specialized Research Fund for the Doctoral Program of Higher Education of China (200805040023)~~
文摘[Objective] This study aimed to investigate the distribution law of different goblet cells in the intestinal tracts of African ostrich chicks. [Method] Alcian blue/pe- riodic acid-schiff reaction （AB/PAS） was adopted to observe and analyze the types and distribution of goblet cells in the intestinal tracts of ostrich chicks. Acid mu- copolysaccharide could be stained blue with alcian blue （AB）, and neutral mu- copolysaccharide could be stained red with periodic acid-schiff reagent （PAS）. [Result] According to AB/PAS results, goblet cells in the intestinal tracts were divided in- to four types： TypeⅠ was pure red, with AB negative result and PAS positive result containing neutral mucoitin; type Ⅱ was pure blue, with AB positive result and PAS negative result containing acidic mucoitin; type Ⅲ was purple reddish, with PAS posi- tive result greater than AB; typeⅣ was purple blue, with AB positive result greater than PAS. Large quantities of goblet cells were found in the intestinal tracts of os- trich chicks, mostly type III and IV.The quantities of goblet cells were decreased gradually in the duodenum, jejunum and ileum, while the quantities were increased in the cecum, colon and rectum. The goblet cells in the large intestine are more than that in the small intestine. The most quantities of goblet cells were contained in rectum. [Conclusion] These results indicate that the distribution of goblet cells is closely related with the structure and function of intestinal tracts. The mucus secret- ed by the goblet Cells plays a series of important roles in the digestion and mucosal immunization.
基金Supported by Specialized Research Fund for The Doctoral Program of Huazhong Agricultural University(200805040023)Natural Science Foundation of China(NSFC)(30471249,30972152)~~
文摘[Objective] This study aimed to investigate the differences in morphological structure of tibias between sick and normal ostrich chicks. [Method] Normal and sick ostrich chicks aged 90 days were used in this research for bone mineral density determination, bone demineralization paraffin section preparation （HE staining）, bone abrasive disc preparation and scanning electron microscopy （SEM） observation, to analyze the differences in microstructure and ultrastructure of tibias between sick ostrich chicks and normal ones. [Result] Bone mineral density of ostrich chicks suffering from leg disease was much lower than that of the normal ones. Compared with normal tibias, less trabeculae were observed in sick tibias, which were attenuated and began to disappear. In addition, trabeculae micro-fracture could be observed under scanning electron microscope; resorption pits on bone slices formed by osteoclast could be observed under scanning electronic microscope. [Conclusion] These results indicate that the sick tibias all have lower bone density and trabeculae microfracture phenomenon in tibias with different diseases, which might be resulted from osteoporosis.
基金supported by the National Natural Science Foundation of China (31472087)the Research and Innovation Program for Graduate Cultivation of Jiangsu Proviance,China in 2010
文摘In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing medical antibodies has been widely used in the production practice. However, there are few studies about the effect of the different injection site and dosage on chicken embryos. The aim of this study was to explore the effects of different injection sites and dosages on chicken embryo hatching rate and development, so as to provide a basis for further studies using the chicken embryo model. Freshly laid eggs （Rugao yellow chicken） were injected with different doses of saline at the tip, equatorial plane and the blunt end of the egg shell, respectively. Egg hatching rate was recorded and compared among injection sites and different doses. A trypan blue stain was also injected at the aforementioned sites and the growth of chicken embryos was observed. The SPSS （statistical package for the social science） software was used to analyze the relationship between the chicken eggs hatching rate and the different injection sites or the different dosages. The experimental results showed that there were significant differences on egg hatching rates among the different injection sites and doses （P〈0.05）. The hatchability of the blunt end injection group was significantly higher than that of the other two sites. The egg hatching rate decreased with increased saline doses. The egg hatching rate of the 100 pL saline injection group was higher than the 200 and 300 μL dosage groups. Ultimately, we suggest that the optimal chicken embryo injection process is during early development, at the blunt end site with a dose less than 100 μL to minimize damage to the egg.
基金This study was supported by National Key R&D Program of China(2017YFD0500500)the earmarked fund for Modern Agro-industry Technology Research System(CARS-40-K12)+1 种基金Beijing Innovation Consortium of Agriculture Research System(BAIC04–2018)the Agricultural Science and Technology Innovation Program(ASTIP)of the Chinese Academy of Agricultural Sciences.
文摘Background:Prenatal nutrition is crucial for embryonic development and neonatal growth,and has the potential to be a main determinant of life-long health.In the present study,we used a layer chick model to investigate the effects of in ovo feeding(IOF)of L-arginine(Arg)on growth,intestinal development,intestinal microbiota and metabolism.The treatments included the non-injected control,saline-injected control,and saline containing 2,6,or 10 mg Arg groups.Results:IOF Arg increased early intestinal index and villus height,and enhanced uptake of residual yolk lipid,contributing to subsequent improvement in the early growth performance of chicks.Prenatal Arg supplementation also increased the early microbialα-diversity,the relative abundance of Lactobacillales and Clostridiales,and decreased the relative abundance of Proteobacteria of cecum in chicks.Furthermore,the shift of cecal microbiota composition and the colonization of potential probiotics were accelerated by IOF of Arg.Simultaneously,metabolomics showed that metabolisms of galactose,taurine-conjugated bile acids and lipids were modulated to direct more energy and nutrients towards rapid growth of intestine at the beginning of post-hatch when embryos received IOF of Arg.Conclusions:Prenatal Arg supplementation showed beneficial effects on the early intestinal development,cecal microbiota and host metabolism of layer chicks,contributing to subsequent improvement in the early growth performance.These findings provide new insight into the role of IOF of Arg in the establishment of the gut microbiota of newly-hatched layer chicks,and can expand our fundamental knowledge about prenatal nutrition,early bacterial colonization and intestinal development in neonate.
文摘A study was under taken to investigate the effect of dietary supplementations of humic acid and esterified glucomannan) on broiler performance and the morphological measurements of small intestine. Two hundred and ten day old broiler chicks were weighed and randomly assigned to seven treatment groups in triplicate. The dietary treatments included T1) control (basal diet without any additives), T2) basal diets supplemented with 0.1% humic acid, T3) basal diets supplemented with 0.2% humic acid, T4) basal diets supplemented with 0.3% humic acid, T5) basal diets supplemented with 0.1% esterified glucomannan, T6) basal diets supplemented with 0.2% esterified glucomannan and T7) basal diets supplemented with 0.3% esterified glucomannan. Different parameters including body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and morphology of small intestine were evaluated during six weeks of experimental period. According to the results, at the end of experimental period, the highest average BWG were recorded in T4 group (fed with 0.3% humic acid), compared to control (T1) and other experimental groups (p < 0.05). Where as, the highest body weight gain were observed during starter period in treatment 7 (fed with 0.3% esterified glucomannan) as compare to other experimental groups (p < 0.05). Statistically, feed intake remained unaffected during the experimental period in all the treatment groups. However, the lowest and the highest feed intake were observed numerically within treatments T4 and T1 with 4229.70 g and 4362.30 g, respectively. Addition of dietary supplements used in the study appeared to have significant effect on the morphology of the small intestine (jejunum mucosal development) of the broilers in different treatment groups. Compared to control group, the inclusion of either humic acid or esterified glucomannon decreased (p < 0.01) the crypt depth and increased villus height respectively (p < 0.05). More ever, the diet supplements with humic acid 0.3% (T4) decreased crypt depth compared to esterified glucomannan and control. The dietary supplementations resulted in an increase in the villus height of intestinal mucosa of broilers. The increase in the villus height was associated with improvement of growth performance for both humic acid and esterified glucomannan. Based on our results it appeared that humic acid and esterified glucomannan can be used as a growth promoter in broiler diets and they can improve the gut health too.
文摘Aim: This study was designed to investigate the effect of busulfan treatment on the proliferation of chicken primordialgerm cells (PGCs) in vivo, focusing on the preferential settlement of PGCs onto the germinal ridges of chicken em-bryos. Methods: Busulfan (250 ng/egg) was injected into the egg white of freshly oviposited fertilized eggs, whichwere then incubated. Embryonic development and viability were examined, and exogenous PGCs collected from embry-onic blood vessels were injected into the germinal crescent region of recipient embryos. The number of PGCs residedonto germinal ridges of the right and left sides were compared. Results: Busulfan had a slight harmful effect on theembryo viability and the PGCs proliferation. The number of PGCs resided onto the left side of germinal ridges wasslightly higher as compared with the right side. Conclusion: Busulfan suppressed the viability of embryos and the pro-liferation of endogenous PGCs in the recipient embryos. However, the number of exogenous PGCs proliferated washigher in embryos treated with busulfan than those without busulfan. Data also suggest the possibility of a preferentialresidence of PGCs toward the left side of the germinal crescent region as compared with the fight, which may be due toa more advanced functional development of the left gonad than the right. (Asian J Androl 1999 Dec; 1: 187-190)
基金financially supported by the Ministry of Education,Science and Culture,Japanthe Society for the Promotion of Science(JSPS)+1 种基金the Sumitomo Foundationthe Nissan Science Foundation
文摘Aim:To examine the transfection of exogenous genes into chick embryos,applying the characteristics of avianleukosis vires(ALV)-induced chicken B cell line DT40 to the production of chimeric birds.Methods:The DT40cells incorporated with exogenous gene(lacZ constructs encoding Escherichia coliβ-galactosidase:β-gal)were intro-duced into chick embryos by the injection of cells into stage X blastoderm.Manipulated eggs were incubated for 3(trial1)or 6(trial 2)days,and the expression of lacZ DNA was detected by a histochemical staining method ofβ-galactosi-dase and polymerase chain reaction(PCR)analysis.Results:The survival rates of the manipulated embryos incu-bated for 3 days(stage 18-20:trial 1)and 6 days(stage 28,30:trial 2)were about 42%and 38%,respectively.The expression rates of the lacZ gene in the embryos in the trials 1 and 2 were about 60%and 23%,respectively,forthe survived embryos.Conclusion:The rate of embryonic viability and expression rate of introduced genes were notso high,but it suggested the possibility of utilizing the DT40 cells as a vector for carrying exogenous genes into chickembryos.
文摘A new selenium source, Nano red elemental selenium (Nano-Se) was used to study the effect on the GPx activity of broiler chick kidney cells (BCKC) in vitro, Sodium selenite (Na_ 2 SeO_ 3 ) and seleno-1-methionine (Se-Met) were used as the controls. The results showed that the effects of three kinds of Se forms on the GPx activity of BCKC were accordant(p>0.05) compared with each other at 0.01,0.05 and 0.10 μmol/L Se concentrations treatments. In the range of 0.00-0.10 μmol/L Se concentrations, the GPx activity increased with elevation of Se concentrations in medium. For the three kinds of Se forms, the GPx activity reached the climax at 0.10 μmol/L Se concentration. At 0.20 and 0.30 μmol/L Se concentrations, the influnces of three kinds of Se forms were not accordant with one another. For Nano-Se, the GPx activity at 0.20 and 0.30 μmol/L Se concentrations remained the same as that at 0.10 μmol/L Se concentration treatment. For Se-Met, the GPx activity at 0.20 μmol/L Se concentration treatment remained the same with 0.10 μmol/L treatment; the GPx activity at 0.30 μmol/L Se concentration treatment was declined significantly(p<0.05) compared with 0.10 or 0.20 μmol/L treatment. For Na_ 2 SeO_ 3 , the GPx activity falled gradually with Se concentration increasing from 0.10 μmol/L to 0.30 μmol/L, and at 0.30 μmol/L Se concentration treatment, the GPx activity was less than the original of BCKC. The results implicated, on the GPx activity of BCKC in vitro, the ranking of width range of the most suitable Se concentration for nutrition curve of the three Se formes is Nano-Se>Se-Met>Na_ 2 SeO_ 3 .
基金supported by National Key Project(2009CB941601)the Joint Funds of the National Natural Science Foundation of China(u0731004)+3 种基金National Natural Science Foundation of China(30871845,30901058 and 30972157)the Natural Science Foundation of Guangdong Province of China(9451064201003790 and 9151064201000056)the Special Fund for Agro-scientific Research in the Public Interest(201003011)Specialized Research Fund for the Doctoral Program of Higher Education of China(20094404120012)
文摘Feed intake control is vital to ensuring optimal nutrition and achieving full potential for growth and development in poultry. The aim of the present study was to investigate the effects of L-leucine, L-glutamate, L-tryptophan and L-arginine on feed intake and the mRNA expression levels of hypothalamic Neuropeptide involved in feed intake regulation in broiler chicks. Leucine, glutamate, tryptophan or arginine was intra-cerebroventricularly （ICV） administrated to 4d-old broiler chicks respectively and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of Neuropeptide Y （NPY）, agouti related protein （AgRP）, pro-opiomelanocortin （POMC）, melanocortin receptor 4 （MC4R） and corticotrophin releasing factor （CRF）. Our results showed that ICV administration of L-leucine （0.15 or 1.5 μmol） significantly （P〈0.05） increased feed intake up to 2 h post-administration period and elevated both hypothalamic NPY and AgRP mRNA expression levels. In contrast, ICV administration of L-glutamate （1.6 μmol） significantly （P 〈 0.05） decreased feed intake 0.25, 0.5 and 2 h post-injection, and increased hypothalamic CRF and MC4R mRNA expression levels. Meanwhile, both L-tryptophan （10 or 100 μg） and L-arginine （20 or 200 μg） had no significant effect on feed intake. These findings suggested that L-leucine and L-glutamate could act within the hypothalamus to influence food intake, and that both orexigenic and anorexigenic Neuropeptide genes might contribute directly to these effects.
基金Supported by Basic Scientific Research Fund of Chongqing City(16423)
文摘[Objective] The paper was to investigate the clinical effects of Nvhuang Fuzheng oral liquid on immunity enhancement,disease resistance and growth promotion of chicks. [Method] In the test,3-day-old Daninghe chicks were divided into normal control group,Nvhuang Fuzheng oral liquid group and positive control group. Chicks were administrated with drugs for 7 d before immunization. After vaccination,chicks were observed for 4 weeks,to statistically count the incidence state of chicks. Effects of Nvhuang Fuzheng oral liquid on growth performance,serum immunoglobulin,cytokine and infectious bursal disease virus( IBDV)antibody were studied. [Result] Compared to normal control group,Nvhuang Fuzheng oral liquid significantly improved the weight of chicks and reduced the feed gain ratio( P < 0. 05); significantly reduced the morbidity and mortality and increased the survival rate of chicks( P < 0. 05); continuously increased IgG,IgM and IL-2 content significantly in the serum of chicks( P < 0. 05); extremely improved IFN-γ content in the serum at 7 d post drug administration( P < 0. 01). After vaccination of IBDV vaccine for 1 and 2 weeks,Nvhuang Fuzheng oral liquid significantly improved IBDV antibody titer and positive rate of chicks compared to normal control group( P < 0. 05); at 3 weeks post immunization,the antibody positive rate reached 100%. [Conclusion]Nvhuang Fuzheng oral liquid improved immunoglobulin and cytokine levels of chicks,enhanced the immunity and reduced the occurrence of diseases( the morbidity was reduced by 15% and the mortality was reduced by 30%),enhanced disease-resistant ability and promoted the growth of chicks. Meantime,it improved the immune effect of IBDV vaccine.
文摘In this experiment, 540 male and female chicks of 1-day-age were selected respectively and reared separately. 3×3 factorial experiment was designed. Gushi chicks were fed with nine diets under different metabolizable energy (ME) and crude protein (CP). Effects of different diets on the performances and carcass ingredients of 0-to 4-week-age Gushi chicks were studied by rearing, comparative slaughter and metabolism experiments. Based on the results of three experiments, ME intake per kilogram metabolic weight was regarded as dependent variable (Y) ,and its corresponding net energy (NE) deposition per kilogram metabolic weight was regarded as independent variable (X) , respectively. Lineal regressive analysis was made according to the mathematic model: Y=a+bX. Maintenance ME( MEm) and the converted coefficient from net energy for gain( NEg) to ME for gain( MEg) were found out, then ME requirement was divided into MEm+ MEg, which is ME=359.14 W0.75+ 10.47△W; CP intake and corresponding metabolic weight were regarded as dependent variable and independent variable respectively, and then regressive analysis was made. The result was CP=0. 57 + 8. 21 W0.7S. Consequently, average daily gain (ADG), average daily feed intake and metabolic weight were put into the regressive equations, and then ME and CP requirements for 0- to 4-week-age Gushi chicks were obtained, 12.38 MJ kg-1 and 20.13%, respectively, the ratio of CP to ME was 16. 26 g MJ-1.
基金Acknowledgment This work was supported by the National Natural Science Foundation of China （No. 30270648 and No. 30500270）, Zhejiang Province Scientific and Technological Project （No. 2005C22052） and Zhejiang Province Science Foundation （No. Y304194）. We thank Dr Ji- Min Zhang of the University of California for linguistic revision of the manuscript.
文摘Aim： To assess whether exogenous estradiol has any effect on migration of primordial germ cells （PGCs） in the chick. Methods： Fertilized eggs were treated with 17beta-estradiol （E2） （80 lag/egg） at stage X （day 0 of incubation）, stages 8-10 （incubation 30 h） and 13-15 （incubation 55 h）. Controls received vehicle （emulsion） only. Changes in PGC number were measured on different days according to developmental stages. Results： In male right gonads, but not in female left gonads, at stages 28-30 （incubation 132 h） significant decreases in the mean number of PGCs aggregating were observed compared with the controls （P 〈 0.05） while the total PGC number in the right and left gonads at each stage did not change （P 〉 0.05）. Conclusion： The present study provides evidence that E2 has significant effects on the localization of PGCs in male right, but not female left, gonads of chicken embryos at stages 28-30, compared with controls. （Asian J Andro12008 Mar; 10： 243-248）
文摘Objective: We established a transplantation tumor model of human osteosarcoma in chick embryo, studied its morphological and biological characteristics, and observed its dynamic process of angiogenesis induction so that a simple and practical model can be provided for studying osteosarcoma. Methods: Human osteosarcoma cells at different concentrations were inoculated in chorioallantoic membrane (CAM) of chick embryos at different embryonic ages to observe the factors affecting the survival of the transplanted osteosarcoma in chick embryo, growth characteristics of the transplantation tumor, and the morphological characteristics and biological characteristics of the transplantation tumor. Results: The transplantation tumor model of human osteosarcoma in chick embryo was successfully established. It was found that the transplantation tumor was easy to grow and it showed strong angiogenesis-inducing effects. Under the light microscope, the transplantation tumor showed a similar tissue structure to human osteosarcoma. Conclusion: It is feasible to establish a transplantation tumor model of human osteosarcoma in chick embryo. The model can be easily duplicated with a simple operation, which provides a useful animal model for studying osteosarcoma.
基金supported by the Key International Cooperation Program of the National Natural Science Foundation of China (31110103916)the National Natural Science Foundation of China (31272465)+1 种基金the Agricultural Science and Technology Innovation Program,China (ASTIP-IAS08)the China Agriculture Research System (CARS-42)
文摘In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos was investigated. The hypothesis that Mn supplementation would enhance the expression of MnSOD in cultured primary myocardial cells of chick embryos was tested. Eggs collected from Mn-depleted Arbor Acres laying breeder hens were incubated for 10 days and then myocardial cells were isolated and cultivated for 8 days. The embryonic myocardial cells on day 6 were treated with Mn in the cell culture medium at different time points when the proportion of cells showing spontaneous contraction was over 95% after the 3-day primary culture. A completely randomized design involving a 3 Mn levels（0, 0.5 and 1.0 mmol L^（-1））×3 incubation time points（12, 24 and 48 h） factorial arrangement of treatments（n=6） was used in the current experiment. The results showed that MnSOD activity and m RNA expression level were induced by Mn and increased with incubation time, which supported the hypothesis that Mn would enhance the expression of the MnSOD gene, and thus might protect myocardial cells from oxidative stress during the chick embryonic development.
基金National Natural Science Foundation of China （#90208011, #30300174, #30070856 , #30421005） National Key Basic Research and Development Program of China （#2002CB713802 , #2005CB522700） Shanghai Key Project of Basic Science Research （#04DZ14005 , #04DZ05608）.
文摘Members of the basic helix-loop-helix （bHLH） gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer （FRET） is used to monitor bHLH protein-protein interactions under various physiological conditions. Tissue-specific bHLH activators, NeuroD 1, Mash 1, Neurogenin 1 （Ngn 1）, Neurogenin2 （Ngn2）, and ubiquitous expressed E47 protein are tagged with enhanced yellow fluorescence protein （EYFP） and enhanced cyan fluorescence protein （ECFP）, respectively. The subcellular localization and mobility ofbHLH fusion proteins are examined in HEK293 cells. By transient transfection and in ovo electroporation, four pairs of tissue-specific bHLH activators and E47 protein are over-expressed in HEK293 cells and developing chick embryo neural tube. With the acceptor photobleaching method, FRET could be detected between these bHLH protein pairs in the nuclei of transfected cells and developing neural tubes. Mashl/E47 and Ngn2/E47 FRET pairs show higher FRET efficiencies in the medial and the lateral half of chick embryo neural tube, respectively. It suggests that these bHLH protein pairs formed functional DNA-protein complexes with regulatory elements of their downstream target genes in the specific regions. This work will help one understand the behaviours of bHLH factors in vivo.
基金Supported by National Key Technology Research and Development Program of China during the Twelfth Five-Year Plan Period(2012BAD14B07-02)
文摘In the present study, Pleurotus eryngii residue was added into conventional feed of Chai chicks and meat-type ducks at different ratios to measure its effects on the production performance of chicks and ducks. The results revealed that the growth performance of chicks and ducks was the best when 20% Pleurotus eryngii residue was added into the feed. Under such condition, the daily weight gain of 8 - 11 and 12 - 15-week-old Chai chicks was increased by 6.8% and 13.5%, and that of 8 - 11 and 12 - 15-week-old ducks was increased by 11.5% and 19.3%, respectively.
