Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine mode...Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine model of pregnancy.We hypothesized that the FGR results from the BPA-induced insufficiency and barrier dysfunction of the placenta,oxidative stress,inflammatory responses,autophagy and endoplasmic reticulum stress(ERS).However,precise mechanisms underlying the BPA-induced placental dysfunction,and subsequently,FGR,as well as the potential involvement of placental ERS in these complications,remain to be investigated.Methods In vivo experiment,16 twin-pregnant(from d 40 to 130 of gestation)Hu ewes were randomly distributed into two groups(8 ewes each).One group served as a control and received corn oil once a day,whereas the other group received BPA(5 mg/kg/d as a subcutaneous injection).In vitro study,ovine trophoblast cells(OTCs)were exposed to 4 treatments,6 replicates each.The OTCs were treated with 400μmol/L BPA,400μmol/L BPA+0.5μg/m L tunicamycin(Tm;ERS activator),400μmol/L BPA+1μmol/L 4-phenyl butyric acid(4-PBA;ERS antagonist)and DMEM/F12 complete medium(control),for 24 h.Results In vivo experiments,pregnant Hu ewes receiving the BPA from 40 to 130 days of pregnancy experienced a decrease in placental efficiency,progesterone(P4)level and fetal weight,and an increase in placental estrogen(E2)level,together with barrier dysfunctions,OS,inflammatory responses,autophagy and ERS in type A cotyledons.In vitro experiment,the OTCs exposed to BPA for 24 h showed an increase in the E2 level and related protein and gene expressions of autophagy,ERS,pro-apoptosis and inflammatory response,and a decrease in the P4 level and the related protein and gene expressions of antioxidant,anti-apoptosis and barrier function.Moreover,treating the OTCs with Tm aggravated BPA-induced dysfunction of barrier and endocrine(the increased E2 level and decreased P4 level),OS,inflammatory responses,autophagy,and ERS.However,treating the OTCs with 4-PBA reversed the counteracted effects of Tm mentioned above.Conclusions In general,the results reveal that BPA exposure can cause ERS in the ovine placenta and OTCs,and ERS induction might aggravate BPA-induced dysfunction of the placental barrier and endocrine,OS,inflammatory responses,and autophagy.These data offer novel mechanistic insights into whether ERS is involved in BPA-mediated placental dysfunction and fetal development.展开更多
The objective of this study was to evaluate the effects of adding formic acid and corn flour supplementation to banana pseudostem silages on the nutritional quality of these silages,growth,digestion,rumen fermentation...The objective of this study was to evaluate the effects of adding formic acid and corn flour supplementation to banana pseudostem silages on the nutritional quality of these silages,growth,digestion,rumen fermentation and cellulolytic bacterial community of Nubian black goats fed these silages.Banana pseudostem silage was prepared either conventionally without any additives(CON)or mixed with 0.6% formic acid(F),10% corn flour(C),or both(F+C).Four experimental diets containing 40% of the corresponding silages were designed with roughage to concentrate ratio of 50:50(dry matter(DM)basis).A total of 48 Nubian black castrated goats(body weight(BW),(22.64±1.82)kg;4-mon-old)were randomized into one of the four treatment groups with 12 replicates of one castrated goat per replicate for each treatment in a completely randomized design.Each group was fed on one of the four experimental diets for 40 days.A factorial arrangement of treatments of 2(formic acid levels:0 and 0.6%)×2(corn flour:0 and 10%)was adopted.Formic acid supplementation increased(P<0.05)average daily gain,as well as lactic acid,propionate and butyric acid and water-soluble carbohydrate concentrations,but decreased(P<0.05)the feed conversion rate,pH value,acetate/propionate ratio,and butyric acid concentration relative to the CON group.Corn flour supplementation increased(P<0.05)the apparent digestibility of crude protein,neutral detergent fiber,and non-fibrous carbohydrate and Fibrobacter succinogenes,Ruminococcus albus,and Butyrivibrio fibrisolvens populations,but decreased(P<0.05)the Ruminococcus flavefaciens population relative to the CON group.There were no F×C treatment interactions(P>0.05)for any of the other indices except for the apparent digestibility of non-fibrous carbohydrate(NFC)(P<0.05).The results demonstrated that adding 0.6% formic acid and 10% corn flour supplementation to banana pseudostem silages improved the nutritional quality of these silages and enhanced the growth performance of Nubian black castrated goats by improving apparent nutrient digestibility,and regulating ruminal fermentation and bacteria populations.展开更多
This study aimed to determine the effect of stage and level of feed intake on energy metabolism, carbon-nitrogen (C-N) balance, and methane emission to determine energy and protein requirements for maintenance of ma...This study aimed to determine the effect of stage and level of feed intake on energy metabolism, carbon-nitrogen (C-N) balance, and methane emission to determine energy and protein requirements for maintenance of maternal body including pregnancy tissues during pregnancy using the method of C-N balance. Twenty-one ewes carrying twin fetuses were randomly divided into three groups of seven ewes each in the digestion and respirometry trial at d 40, 100, and 130 of gestation, respectively. Three groups were fed a mixed diet either for ad lib#urn intake, 70 or 50% of the ad libfum intake during pregnancy. The results showed that the apparent digestibility of C and N were increased as feeding levels decreased at each stage of gestation. The daily net energy requirements for maintenance (NEro) were 295.80, 310.09, and 323.59 kJ kg-1 BW0.75 (metabolic body weight) with a partial efficiency of metabolisable energy utilization for maintenance of 0.664, 0.644, and 0.620 at d 40, 100, and 130 of gestation, respectively. The daily net protein requirements for maintenance were 1.99, 2.35, and 2.99 g kg-1 BW0.75 at d 40, 100, and 130 of gestation, respectively. These results for the nutritional requirements of the net energy and protein may help to formulate more balanced diets for Hu sheep during pregnancy.展开更多
Dietary nutrient manipulation(e.g.protein fractions)could lower the environmental footprints of ruminants,especially reactive nitrogen(N).This study investigated the impacts of dietary soluble protein(SP)levels with d...Dietary nutrient manipulation(e.g.protein fractions)could lower the environmental footprints of ruminants,especially reactive nitrogen(N).This study investigated the impacts of dietary soluble protein(SP)levels with decreased crude protein(CP)on intestinal N absorption,hindgut N metabolism,fecal microbiota and metabolites,and their linkage with N metabolism phenotype.Thirty-two male Hu sheep,with an age of six months and an initial BW of 40.37±1.18 kg,were randomly assigned to four dietary groups.The control diet(CON),aligning with NRC standards,maintained a CP content of 16.7%on a dry matter basis.Conversely,the experimental diets(LPA,LPB,and LPC)featured a 10%reduction in CP compared with CON,accompanied by SP adjustments to 21.2%,25.9%,and 29.4%of CP,respectively.Our results showed that low-protein diets led to significant reductions in the concentrations of plasma creatinine,ammonia,urea N,and fecal total short-chain fatty acids(SCFA)(P<0.05).Notably,LPB and LPC exhibited increased total SCFA and propionate concentrations compared with LPA(P<0.05).The enrichment of the Prevotella genus in fecal microbiota associated with energy metabolism and amino acid(AA)biosynthesis pathways was evident with SP levels in low-protein diets of approximately 25%to 30%.Moreover,LPB and LPC diets demonstrated a decrease in fecal NH_(4)^(+) eN and NO_(2) eN contents as well as urease activity,compared with CON(P<0.05).Concomitantly,reductions in fecal glutamic acid dehydrogenase gene(gdh),nitrite reductase gene(nirS),and nitric oxide reductase gene(norB)abundances were observed(P<0.05),pointing towards a potential reduction in reactive N production at the source.Of significance,the up-regulation of mRNA abundance of AA and peptide transporters in the small intestine(duodenum,jejunum,and ileum)and the elevated concentration of plasma AA(e.g.arginine,methionine,aspartate,glutamate,etc.)underscored the enhancement of N absorption and N efficiency.In summary,a 10%reduction in CP,coupled with an SP level of approximately 25%to 30%,demonstrated the potential to curtail reactive N emissions through fecal Prevotella enrichment and improve intestinal energy and N utilization efficiency.展开更多
Previous studies have revealed that dietary N-carbamylglutamate(NCG)or L-arginine(Arg)improves small intestinal integrity and immune function in suckling Hu lambs that have experienced intrauterine growth retardation(...Previous studies have revealed that dietary N-carbamylglutamate(NCG)or L-arginine(Arg)improves small intestinal integrity and immune function in suckling Hu lambs that have experienced intrauterine growth retardation(IUGR).Whether these nutrients alter redox status and apoptosis in the colon of IUGR lambs is still unknown.This study,therefore,aimed at investigating whether dietary supplementation of Arg or NCG alters colonic redox status,apoptosis and endoplasmic reticulum(ER)stress and the underlying mechanism of these alterations in IUGR suckling Hu lambs.Forty-eight 7-d old Hu lambs,including 12 with normal birth weight(4.25±0.14 kg)and 36 with IUGR(3.01±0.12 kg),were assigned to 4 treatment groups(n=12 each;6 males and 6 females)for 3 weeks.The treatment groups were control(CON),IUGR,IUGR+Arg and IUGR+NCG.Relative to IUGR lambs,superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)content,as well as proliferation index,were higher(P<0.05)whereas reactive oxygen species(ROS),malondialdehyde(MDA)levels and apoptotic cell numbers were lower(P<0.05)in colonic tissue for both IUGR+Arg and NCG lambs.Both m RNA and protein levels of C/EBP homologous protein 10(CHOP10),B-cell lymphoma/leukaemia 2(Bcl-2)-associated X protein(Bax),apoptosis antigen 1(Fas),activating transcription factor 6(ATF6),caspase 3,and glucose-regulated protein 78(GRP78)were lower(P<0.05)while glutathione peroxidase 1(GPx1),Bcl-2 and catalase(CAT)levels were higher(P<0.05)in colonic tissue for IUGR+Arg and IUGR+NCG lambs compared with IUGR lambs.Based on our results,dietary NCG or Arg supplementation can improve colonic redox status and suppress apoptosis via death receptor-dependent,mitochondrial and ER stress pathways in IUGR suckling lambs.展开更多
Our previous studies demonstrated that prenatal in utero growth restriction impairs postnatal intestinal function.Thus,improving postpartal intestinal absorption capacity and growth by manipulating the maternal diet p...Our previous studies demonstrated that prenatal in utero growth restriction impairs postnatal intestinal function.Thus,improving postpartal intestinal absorption capacity and growth by manipulating the maternal diet prepartum is of importance.This work was conducted to determine whether supplementation of N-carbamylglutamate(NCG)or rumen-protected L-arginine(RP-Arg)increased fetal intestinal amino acid(AA)profiles in intrauterine growth retardation(IUGR)fetuses.On d 35 of gestation,Hu ewes(n=32)carrying twin fetuses were randomized into 4 groups(8 ewes and 16 fetuses in each group),where diets were as follows:100%of nutrient requirements recommended by National Research Council(NRC,2007)(CON);50%of nutrient requirements recommended by NRC(2007)(RES);RES+RPArg(20 g/d),(RES+ARG);and RES+NCG(5 g/d),(RES+NCG).On d 110 of gestation,both fetal and maternal tissues were collected and weighed.Compared with RES,solute carrier family 1,member 5(SLC1A5)was upregulated(P<0.05)within fetal jejunum,duodenum and ileum when supplementing NCG and RP-Arg.Relative to RES,RP-Arg or NCG supplementation to RES resulted in upregulation(P<0.05)of peptide transporter 1 protein abundance within the fetal ileum.NCG or RP-Arg supplementation to RES also upregulated phosphorylated mechanistic target of rapamycin(pmTOR)-to-mTOR ratio in the fetal ileum induced by IUGR(P<0.05).As a result,during IUGR,supplementation of Arg or NCG affected intestinal AA profiles in the fetus in part through controlling mTOR signal transduction as well as AA and peptide transport.Future studies should be conducted to understand the role(if any)of the placenta on the improvement of growth and AA profiles independent of the fetal intestine.This would help demonstrate the relative contribution of intestinal uptake in fetal life.展开更多
Dairy cattle are frequently fed high-concentrate(HC)diets in modern intensive feeding systems,especially in the transition period.During this period,cows face many alterations that include hormonal changes and shiftin...Dairy cattle are frequently fed high-concentrate(HC)diets in modern intensive feeding systems,especially in the transition period.During this period,cows face many alterations that include hormonal changes and shifting to a lactating state.Switching to a HC diet that may disrupt the ruminal microbiota balance can lead to subacute ruminal acidosis(SARA).Moreover,the main factor shaping the rumen microbiota is dietary composition,especially the ratio of starch to fibrous carbohydrates.Feeding highly fermentable carbohydrate diets after adaptation to forage diets leads to a rumen fermentation rate that exceeds rumen absorption and buffering rates,resulting in a reduction in ruminal pH.As a result of Gram-negative bacterial cell lysis,an increase in harmful ruminal bacterial metabolites,including lipopolysaccharide,lactic acid,and histamine,is observed.The interactions between the host immune system and the ruminal microbiota play an essential role in many physiological processes and the development of the disorder.Progress in DNA sequencing and bioinformatics platforms provides new opportunities to investigate the composition of ruminal microbes and yields unique advances in understanding ecology of the rumen.Subacute ruminal acidosis is linked with a change in the ruminal microbiota structure and richness and with other metabolic disorders;such as rumenitis,milk fat depression,laminitis,and liver abscesses.Therefore,this review aims to explore a better understanding of the crosstalk between diet and microbiota in the prevalence of rumen acidosis and its consequences,which is crucial for control strategies such as feeding management,and supplementation with thiamine,prebiotics,and probiotics.展开更多
This study aimed to investigate the effects of dietary supplementation of underfed Hu ewes from d 35 to110 of gestation with either rumen-protected L-arginine(RP-Arg)or N-carbamylglutamate(NCG)on placental amino acid(...This study aimed to investigate the effects of dietary supplementation of underfed Hu ewes from d 35 to110 of gestation with either rumen-protected L-arginine(RP-Arg)or N-carbamylglutamate(NCG)on placental amino acid(AA)transport,angiogenic gene expression,and steroid anabolism.On d 35 of gestation,32 Hu ewes carrying twin fetuses were randomly divided into four treatment groups,each consisting of eight ewes,and were fed the following diets:A diet providing 100%of NRC’s nutrient requirements for pregnant ewes(CON);A diet providing 50%of NRC’s nutrient requirements for pregnant ewes(RES);RES diet plus 5 g/d NCG(RES+NCG);or RES diet plus 20 g/d RP-Arg(RES+ARG).On the d 110 of pregnancy,blood samples were taken from the mother,and samples were collected from type A cotyledons(COT;the fetal portions of the placenta).The levels of 17β-estradiol and progesterone in the maternal serum and both the capillary area density(CAD)and capillary surface density(CSD)in type A COT were decreased in response to Arg or NCG supplementation when compared to the RES group.The concentrations of arginine,leucine,putrescine and spermidine in type A COT were higher(P<0.05)in the RES+ARG or RES+NCG group than in the RES group.The mRNA expression levels of inducible nitric oxide synthase(iNOS)and solute carrier family 15,member 1(SLC15A1)were increased(P<0.05)while those of progesterone receptor(PGR)and fibroblast growth factor 2(FGF2)were decreased in type A COT by supplementation with either NCG or RP-Arg compared to the RES group.The results suggest that providing underfed pregnant ewes from d 35 to 110 of gestation with a diet supplemented with NCG or RP-Arg improves placental AA transport,and reduces the expression of angiogenic growth factor genes and steroid anabolism,leading to better fetal development.展开更多
This study aimed to explore whether dietary rumen-protected L-arginine(RP-Arg)or N-carbamylglutamate(NCG)supplementation to feed-restricted pregnant ewes counteracts fetal hepatic inflammation and innate immune dysfun...This study aimed to explore whether dietary rumen-protected L-arginine(RP-Arg)or N-carbamylglutamate(NCG)supplementation to feed-restricted pregnant ewes counteracts fetal hepatic inflammation and innate immune dysfunction associated with intrauterine growth retardation(IUGR)in ovine fetuses.On d 35 of pregnancy,twin-bearing Hu ewes(n=32)were randomly assigned to 4 treatment groups(8 ewes and 16 fetuses per group)and fed diets containing 100%of the NRC requirements(CON),50%of the NRC requirements(RES),RES+RP-Arg(20 g/d)(RESA),or RES+NCG(5 g/d)(RESN).At 08:00 on d 110 of gestation,fetal blood and liver tissue samples were collected.The levels of triglyceride,free fatty acid,cholesterol andβ-hydroxybutyrate in the fetal blood of RESA and RESN groups were lower(P<0.05)than those of the RES group,but were higher(P<0.05)than those of the CON group.The interleukin(IL)-6 and IL-1 levels in fetal blood and liver tissue as well as the myeloid differentiation primary response 88(MyD88),transforming growth factorβ(TGFβ),and nuclear factor kappa B(NF-κB)mRNA levels in the fetal liver were decreased(P<0.05)by the NCG or RP-Arg supplementation compared to the RES treatment.Similarly,the toll-like receptor(TLR)-4,MyD88,TGFβ,and p-c-Jun N-terminal kinase(JNK)protein levels in the fetal liver were reduced(P<0.05)in the NCG and RP-Arg-supplemented groups compared to the RES group.These results showed that dietary supplementation of RP-Arg or NCG to underfed pregnant ewes could protect against IUGR fetal hepatic inflammation via improving lipid metabolism,down-regulating the TLR-4 and the inflammatory JNK and NF-icB signaling pathways,and decreasing cytokine production in ovine fetal blood and liver tissue.展开更多
The objective of this study was to investigate the effects of dietary administration of L-arginine(Arg)or N-carbamylglutamate(NCG)on hepatic energy status and mitochondrial functions in suckling Hu lambs with intraute...The objective of this study was to investigate the effects of dietary administration of L-arginine(Arg)or N-carbamylglutamate(NCG)on hepatic energy status and mitochondrial functions in suckling Hu lambs with intrauterine growth retardation(IUGR).Forty-eight newborn Hu lambs of 7 d old were allocated into 4 treatment groups of 12 lambs each,in triplicate with 4 lambs per replicate(2 males and 2 females)as follows:CON(lambs of normal birth weight,4.25±0.14 kg),IUGR(3.01±0.12 kg),IUGR+1%Arg(2.99±0.13 kg),or IUGR+0.1%NCG(3.03±0.11 kg).The experiment lasted for 21 d,until d 28 after birth,and all lambs were fed milk replacer as a basal diet.Compared with IUGR lambs,NCG or Arg administration increased(P<0.05)the adenosine triphosphate(ATP)level and the activities of com-plexes I/III/IV,isocitrate dehydrogenase and citrate synthase in the liver.Compared with CON lambs,the relative mRNA levels of adenosine monophosphate-activated protein kinaseα1(AMPKα1),peroxisome proliferator-activated receptorγcoactivator-1α(PGC1α)and transcription factor A(TFAM)were increased(P<0.05)in the liver of IUGR lambs,but were decreased(P<0.05)in the liver of NCG-or Arg-treated lambs compared with those in the IUGR lambs.Compared with IUGR lambs,NCG or Arg administration decreased(P<0.05)the total AMPKα(tAMPKα)-to-phosphorylated AMPKα(pAMPKα)ratio and the protein expression of PGC1αand TFAM.The results suggested that dietary Arg or NCG supplements improved hepatic energy status and mitochondrial function and inhibited the AMPK-PGC1α-TFAM pathway in IUGR suckling lambs.展开更多
基金supported by the fund for the National 14th Five-Year Plan Key Research and Development Program(2021YFD1600702)XPCC Agricultural Science and Technology Innovation Project(NCG202232)the Top Talents Award Plan of Yangzhou University(2020)。
文摘Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine model of pregnancy.We hypothesized that the FGR results from the BPA-induced insufficiency and barrier dysfunction of the placenta,oxidative stress,inflammatory responses,autophagy and endoplasmic reticulum stress(ERS).However,precise mechanisms underlying the BPA-induced placental dysfunction,and subsequently,FGR,as well as the potential involvement of placental ERS in these complications,remain to be investigated.Methods In vivo experiment,16 twin-pregnant(from d 40 to 130 of gestation)Hu ewes were randomly distributed into two groups(8 ewes each).One group served as a control and received corn oil once a day,whereas the other group received BPA(5 mg/kg/d as a subcutaneous injection).In vitro study,ovine trophoblast cells(OTCs)were exposed to 4 treatments,6 replicates each.The OTCs were treated with 400μmol/L BPA,400μmol/L BPA+0.5μg/m L tunicamycin(Tm;ERS activator),400μmol/L BPA+1μmol/L 4-phenyl butyric acid(4-PBA;ERS antagonist)and DMEM/F12 complete medium(control),for 24 h.Results In vivo experiments,pregnant Hu ewes receiving the BPA from 40 to 130 days of pregnancy experienced a decrease in placental efficiency,progesterone(P4)level and fetal weight,and an increase in placental estrogen(E2)level,together with barrier dysfunctions,OS,inflammatory responses,autophagy and ERS in type A cotyledons.In vitro experiment,the OTCs exposed to BPA for 24 h showed an increase in the E2 level and related protein and gene expressions of autophagy,ERS,pro-apoptosis and inflammatory response,and a decrease in the P4 level and the related protein and gene expressions of antioxidant,anti-apoptosis and barrier function.Moreover,treating the OTCs with Tm aggravated BPA-induced dysfunction of barrier and endocrine(the increased E2 level and decreased P4 level),OS,inflammatory responses,autophagy,and ERS.However,treating the OTCs with 4-PBA reversed the counteracted effects of Tm mentioned above.Conclusions In general,the results reveal that BPA exposure can cause ERS in the ovine placenta and OTCs,and ERS induction might aggravate BPA-induced dysfunction of the placental barrier and endocrine,OS,inflammatory responses,and autophagy.These data offer novel mechanistic insights into whether ERS is involved in BPA-mediated placental dysfunction and fetal development.
基金This research was supported by the China Special Fund for Agro-scientific Research in the Public Interest(Investigation on strategies of fattening and high-quality meat productive techniques for herbivores based on resources of unconventional roughage in Southern China)(201303144)the Top Talents Award Plan of Yangzhou University,China(2016,2020)+4 种基金the Cyanine Project of Yangzhou University(2020)the Technology Specialty Fund for Cooperation between Jilin Province and the Chinese Academy of Sciences,2016SYHZ0022)the National Key Research and Development Program of China(2016YFD0700201)the National Natural Science Foundation of China(31902180)the Natural Science Foundation of Jiangsu Province Research Project,China(BK20170488).
文摘The objective of this study was to evaluate the effects of adding formic acid and corn flour supplementation to banana pseudostem silages on the nutritional quality of these silages,growth,digestion,rumen fermentation and cellulolytic bacterial community of Nubian black goats fed these silages.Banana pseudostem silage was prepared either conventionally without any additives(CON)or mixed with 0.6% formic acid(F),10% corn flour(C),or both(F+C).Four experimental diets containing 40% of the corresponding silages were designed with roughage to concentrate ratio of 50:50(dry matter(DM)basis).A total of 48 Nubian black castrated goats(body weight(BW),(22.64±1.82)kg;4-mon-old)were randomized into one of the four treatment groups with 12 replicates of one castrated goat per replicate for each treatment in a completely randomized design.Each group was fed on one of the four experimental diets for 40 days.A factorial arrangement of treatments of 2(formic acid levels:0 and 0.6%)×2(corn flour:0 and 10%)was adopted.Formic acid supplementation increased(P<0.05)average daily gain,as well as lactic acid,propionate and butyric acid and water-soluble carbohydrate concentrations,but decreased(P<0.05)the feed conversion rate,pH value,acetate/propionate ratio,and butyric acid concentration relative to the CON group.Corn flour supplementation increased(P<0.05)the apparent digestibility of crude protein,neutral detergent fiber,and non-fibrous carbohydrate and Fibrobacter succinogenes,Ruminococcus albus,and Butyrivibrio fibrisolvens populations,but decreased(P<0.05)the Ruminococcus flavefaciens population relative to the CON group.There were no F×C treatment interactions(P>0.05)for any of the other indices except for the apparent digestibility of non-fibrous carbohydrate(NFC)(P<0.05).The results demonstrated that adding 0.6% formic acid and 10% corn flour supplementation to banana pseudostem silages improved the nutritional quality of these silages and enhanced the growth performance of Nubian black castrated goats by improving apparent nutrient digestibility,and regulating ruminal fermentation and bacteria populations.
基金supported by the earmarked fund for China Agriculture Research System (CARS-39)the Agro-scientific Research in the Public Interest,China (201303143)
文摘This study aimed to determine the effect of stage and level of feed intake on energy metabolism, carbon-nitrogen (C-N) balance, and methane emission to determine energy and protein requirements for maintenance of maternal body including pregnancy tissues during pregnancy using the method of C-N balance. Twenty-one ewes carrying twin fetuses were randomly divided into three groups of seven ewes each in the digestion and respirometry trial at d 40, 100, and 130 of gestation, respectively. Three groups were fed a mixed diet either for ad lib#urn intake, 70 or 50% of the ad libfum intake during pregnancy. The results showed that the apparent digestibility of C and N were increased as feeding levels decreased at each stage of gestation. The daily net energy requirements for maintenance (NEro) were 295.80, 310.09, and 323.59 kJ kg-1 BW0.75 (metabolic body weight) with a partial efficiency of metabolisable energy utilization for maintenance of 0.664, 0.644, and 0.620 at d 40, 100, and 130 of gestation, respectively. The daily net protein requirements for maintenance were 1.99, 2.35, and 2.99 g kg-1 BW0.75 at d 40, 100, and 130 of gestation, respectively. These results for the nutritional requirements of the net energy and protein may help to formulate more balanced diets for Hu sheep during pregnancy.
基金supported by Bintuan Science and Technology Program (2023AB078)Bintuan Agricultural Innovation Project (NCG202232)+2 种基金China Scholarship Council (NO.202208320271)Postgraduate Research&Practice Innovation Program of Jiangsu Province (KYCX22_3532,SJCX23_1991)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD),China.
文摘Dietary nutrient manipulation(e.g.protein fractions)could lower the environmental footprints of ruminants,especially reactive nitrogen(N).This study investigated the impacts of dietary soluble protein(SP)levels with decreased crude protein(CP)on intestinal N absorption,hindgut N metabolism,fecal microbiota and metabolites,and their linkage with N metabolism phenotype.Thirty-two male Hu sheep,with an age of six months and an initial BW of 40.37±1.18 kg,were randomly assigned to four dietary groups.The control diet(CON),aligning with NRC standards,maintained a CP content of 16.7%on a dry matter basis.Conversely,the experimental diets(LPA,LPB,and LPC)featured a 10%reduction in CP compared with CON,accompanied by SP adjustments to 21.2%,25.9%,and 29.4%of CP,respectively.Our results showed that low-protein diets led to significant reductions in the concentrations of plasma creatinine,ammonia,urea N,and fecal total short-chain fatty acids(SCFA)(P<0.05).Notably,LPB and LPC exhibited increased total SCFA and propionate concentrations compared with LPA(P<0.05).The enrichment of the Prevotella genus in fecal microbiota associated with energy metabolism and amino acid(AA)biosynthesis pathways was evident with SP levels in low-protein diets of approximately 25%to 30%.Moreover,LPB and LPC diets demonstrated a decrease in fecal NH_(4)^(+) eN and NO_(2) eN contents as well as urease activity,compared with CON(P<0.05).Concomitantly,reductions in fecal glutamic acid dehydrogenase gene(gdh),nitrite reductase gene(nirS),and nitric oxide reductase gene(norB)abundances were observed(P<0.05),pointing towards a potential reduction in reactive N production at the source.Of significance,the up-regulation of mRNA abundance of AA and peptide transporters in the small intestine(duodenum,jejunum,and ileum)and the elevated concentration of plasma AA(e.g.arginine,methionine,aspartate,glutamate,etc.)underscored the enhancement of N absorption and N efficiency.In summary,a 10%reduction in CP,coupled with an SP level of approximately 25%to 30%,demonstrated the potential to curtail reactive N emissions through fecal Prevotella enrichment and improve intestinal energy and N utilization efficiency.
基金funded by the National Natural Science Foundation of China(31902180)the Top Talents Award Plan of Yangzhou University(2020)the Cyanine Project of Yangzhou University(2020)。
文摘Previous studies have revealed that dietary N-carbamylglutamate(NCG)or L-arginine(Arg)improves small intestinal integrity and immune function in suckling Hu lambs that have experienced intrauterine growth retardation(IUGR).Whether these nutrients alter redox status and apoptosis in the colon of IUGR lambs is still unknown.This study,therefore,aimed at investigating whether dietary supplementation of Arg or NCG alters colonic redox status,apoptosis and endoplasmic reticulum(ER)stress and the underlying mechanism of these alterations in IUGR suckling Hu lambs.Forty-eight 7-d old Hu lambs,including 12 with normal birth weight(4.25±0.14 kg)and 36 with IUGR(3.01±0.12 kg),were assigned to 4 treatment groups(n=12 each;6 males and 6 females)for 3 weeks.The treatment groups were control(CON),IUGR,IUGR+Arg and IUGR+NCG.Relative to IUGR lambs,superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)content,as well as proliferation index,were higher(P<0.05)whereas reactive oxygen species(ROS),malondialdehyde(MDA)levels and apoptotic cell numbers were lower(P<0.05)in colonic tissue for both IUGR+Arg and NCG lambs.Both m RNA and protein levels of C/EBP homologous protein 10(CHOP10),B-cell lymphoma/leukaemia 2(Bcl-2)-associated X protein(Bax),apoptosis antigen 1(Fas),activating transcription factor 6(ATF6),caspase 3,and glucose-regulated protein 78(GRP78)were lower(P<0.05)while glutathione peroxidase 1(GPx1),Bcl-2 and catalase(CAT)levels were higher(P<0.05)in colonic tissue for IUGR+Arg and IUGR+NCG lambs compared with IUGR lambs.Based on our results,dietary NCG or Arg supplementation can improve colonic redox status and suppress apoptosis via death receptor-dependent,mitochondrial and ER stress pathways in IUGR suckling lambs.
基金The research was supported by the fund for the National Natural Science Foundation of China(31902180)the Science and Technology Innovation Project of Yangzhou University(2019CXJ152)+2 种基金the Top Talents Award Plan of Yangzhou University(2019)the funds from State Key Laboratory of Sheep Genetic Improvement and Healthy Production(2021ZD07)the Cyanine Project of Yangzhou University(2020).
文摘Our previous studies demonstrated that prenatal in utero growth restriction impairs postnatal intestinal function.Thus,improving postpartal intestinal absorption capacity and growth by manipulating the maternal diet prepartum is of importance.This work was conducted to determine whether supplementation of N-carbamylglutamate(NCG)or rumen-protected L-arginine(RP-Arg)increased fetal intestinal amino acid(AA)profiles in intrauterine growth retardation(IUGR)fetuses.On d 35 of gestation,Hu ewes(n=32)carrying twin fetuses were randomized into 4 groups(8 ewes and 16 fetuses in each group),where diets were as follows:100%of nutrient requirements recommended by National Research Council(NRC,2007)(CON);50%of nutrient requirements recommended by NRC(2007)(RES);RES+RPArg(20 g/d),(RES+ARG);and RES+NCG(5 g/d),(RES+NCG).On d 110 of gestation,both fetal and maternal tissues were collected and weighed.Compared with RES,solute carrier family 1,member 5(SLC1A5)was upregulated(P<0.05)within fetal jejunum,duodenum and ileum when supplementing NCG and RP-Arg.Relative to RES,RP-Arg or NCG supplementation to RES resulted in upregulation(P<0.05)of peptide transporter 1 protein abundance within the fetal ileum.NCG or RP-Arg supplementation to RES also upregulated phosphorylated mechanistic target of rapamycin(pmTOR)-to-mTOR ratio in the fetal ileum induced by IUGR(P<0.05).As a result,during IUGR,supplementation of Arg or NCG affected intestinal AA profiles in the fetus in part through controlling mTOR signal transduction as well as AA and peptide transport.Future studies should be conducted to understand the role(if any)of the placenta on the improvement of growth and AA profiles independent of the fetal intestine.This would help demonstrate the relative contribution of intestinal uptake in fetal life.
基金the National Natural Science Foundation of China(NSFC No.31872988No.31572429)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PADA).
文摘Dairy cattle are frequently fed high-concentrate(HC)diets in modern intensive feeding systems,especially in the transition period.During this period,cows face many alterations that include hormonal changes and shifting to a lactating state.Switching to a HC diet that may disrupt the ruminal microbiota balance can lead to subacute ruminal acidosis(SARA).Moreover,the main factor shaping the rumen microbiota is dietary composition,especially the ratio of starch to fibrous carbohydrates.Feeding highly fermentable carbohydrate diets after adaptation to forage diets leads to a rumen fermentation rate that exceeds rumen absorption and buffering rates,resulting in a reduction in ruminal pH.As a result of Gram-negative bacterial cell lysis,an increase in harmful ruminal bacterial metabolites,including lipopolysaccharide,lactic acid,and histamine,is observed.The interactions between the host immune system and the ruminal microbiota play an essential role in many physiological processes and the development of the disorder.Progress in DNA sequencing and bioinformatics platforms provides new opportunities to investigate the composition of ruminal microbes and yields unique advances in understanding ecology of the rumen.Subacute ruminal acidosis is linked with a change in the ruminal microbiota structure and richness and with other metabolic disorders;such as rumenitis,milk fat depression,laminitis,and liver abscesses.Therefore,this review aims to explore a better understanding of the crosstalk between diet and microbiota in the prevalence of rumen acidosis and its consequences,which is crucial for control strategies such as feeding management,and supplementation with thiamine,prebiotics,and probiotics.
基金The research was supported by the fund for the Top Talents Award Plan of Yangzhou University(2020)the Cyanine Project of Yangzhou University(2020).
文摘This study aimed to investigate the effects of dietary supplementation of underfed Hu ewes from d 35 to110 of gestation with either rumen-protected L-arginine(RP-Arg)or N-carbamylglutamate(NCG)on placental amino acid(AA)transport,angiogenic gene expression,and steroid anabolism.On d 35 of gestation,32 Hu ewes carrying twin fetuses were randomly divided into four treatment groups,each consisting of eight ewes,and were fed the following diets:A diet providing 100%of NRC’s nutrient requirements for pregnant ewes(CON);A diet providing 50%of NRC’s nutrient requirements for pregnant ewes(RES);RES diet plus 5 g/d NCG(RES+NCG);or RES diet plus 20 g/d RP-Arg(RES+ARG).On the d 110 of pregnancy,blood samples were taken from the mother,and samples were collected from type A cotyledons(COT;the fetal portions of the placenta).The levels of 17β-estradiol and progesterone in the maternal serum and both the capillary area density(CAD)and capillary surface density(CSD)in type A COT were decreased in response to Arg or NCG supplementation when compared to the RES group.The concentrations of arginine,leucine,putrescine and spermidine in type A COT were higher(P<0.05)in the RES+ARG or RES+NCG group than in the RES group.The mRNA expression levels of inducible nitric oxide synthase(iNOS)and solute carrier family 15,member 1(SLC15A1)were increased(P<0.05)while those of progesterone receptor(PGR)and fibroblast growth factor 2(FGF2)were decreased in type A COT by supplementation with either NCG or RP-Arg compared to the RES group.The results suggest that providing underfed pregnant ewes from d 35 to 110 of gestation with a diet supplemented with NCG or RP-Arg improves placental AA transport,and reduces the expression of angiogenic growth factor genes and steroid anabolism,leading to better fetal development.
基金supported by the fund for the National Natural Science Foundation of China(31902180)the Top Talents Award Plan of Yangzhou University(2019)+2 种基金the Cyanine Project of Yangzhou University(2020)the funds from State Key Laboratory of Sheep Genetic Improvement and Healthy Production(2021ZD07)Yangzhou University Science and Technology Innovation Foundation(2019CXJ152)。
文摘This study aimed to explore whether dietary rumen-protected L-arginine(RP-Arg)or N-carbamylglutamate(NCG)supplementation to feed-restricted pregnant ewes counteracts fetal hepatic inflammation and innate immune dysfunction associated with intrauterine growth retardation(IUGR)in ovine fetuses.On d 35 of pregnancy,twin-bearing Hu ewes(n=32)were randomly assigned to 4 treatment groups(8 ewes and 16 fetuses per group)and fed diets containing 100%of the NRC requirements(CON),50%of the NRC requirements(RES),RES+RP-Arg(20 g/d)(RESA),or RES+NCG(5 g/d)(RESN).At 08:00 on d 110 of gestation,fetal blood and liver tissue samples were collected.The levels of triglyceride,free fatty acid,cholesterol andβ-hydroxybutyrate in the fetal blood of RESA and RESN groups were lower(P<0.05)than those of the RES group,but were higher(P<0.05)than those of the CON group.The interleukin(IL)-6 and IL-1 levels in fetal blood and liver tissue as well as the myeloid differentiation primary response 88(MyD88),transforming growth factorβ(TGFβ),and nuclear factor kappa B(NF-κB)mRNA levels in the fetal liver were decreased(P<0.05)by the NCG or RP-Arg supplementation compared to the RES treatment.Similarly,the toll-like receptor(TLR)-4,MyD88,TGFβ,and p-c-Jun N-terminal kinase(JNK)protein levels in the fetal liver were reduced(P<0.05)in the NCG and RP-Arg-supplemented groups compared to the RES group.These results showed that dietary supplementation of RP-Arg or NCG to underfed pregnant ewes could protect against IUGR fetal hepatic inflammation via improving lipid metabolism,down-regulating the TLR-4 and the inflammatory JNK and NF-icB signaling pathways,and decreasing cytokine production in ovine fetal blood and liver tissue.
基金supported by the fund for the National Natural Science Foundation of China(31902180)the Research Project of Natural Science Foundation of Jiangsu Province(BK20170488)+3 种基金the China Postdoctoral Science Foundation(2017M610358)the Science and Technology Innovation Project of Yangzhou University(2019CXJ152)the Top Talents Award Plan of Yangzhou University(2020)the Cyanine Project of Yangzhou University(2020)
文摘The objective of this study was to investigate the effects of dietary administration of L-arginine(Arg)or N-carbamylglutamate(NCG)on hepatic energy status and mitochondrial functions in suckling Hu lambs with intrauterine growth retardation(IUGR).Forty-eight newborn Hu lambs of 7 d old were allocated into 4 treatment groups of 12 lambs each,in triplicate with 4 lambs per replicate(2 males and 2 females)as follows:CON(lambs of normal birth weight,4.25±0.14 kg),IUGR(3.01±0.12 kg),IUGR+1%Arg(2.99±0.13 kg),or IUGR+0.1%NCG(3.03±0.11 kg).The experiment lasted for 21 d,until d 28 after birth,and all lambs were fed milk replacer as a basal diet.Compared with IUGR lambs,NCG or Arg administration increased(P<0.05)the adenosine triphosphate(ATP)level and the activities of com-plexes I/III/IV,isocitrate dehydrogenase and citrate synthase in the liver.Compared with CON lambs,the relative mRNA levels of adenosine monophosphate-activated protein kinaseα1(AMPKα1),peroxisome proliferator-activated receptorγcoactivator-1α(PGC1α)and transcription factor A(TFAM)were increased(P<0.05)in the liver of IUGR lambs,but were decreased(P<0.05)in the liver of NCG-or Arg-treated lambs compared with those in the IUGR lambs.Compared with IUGR lambs,NCG or Arg administration decreased(P<0.05)the total AMPKα(tAMPKα)-to-phosphorylated AMPKα(pAMPKα)ratio and the protein expression of PGC1αand TFAM.The results suggested that dietary Arg or NCG supplements improved hepatic energy status and mitochondrial function and inhibited the AMPK-PGC1α-TFAM pathway in IUGR suckling lambs.