Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model

Background Intrauterine growth retardation(IUGR)affects intestinal growth,morphology,and function,which leads to poor growth performance and high mortality.The present study explored whether maternal dietary methyl donor(MET)supplementation alleviates IUGR and enhances offspring’s growth performance by improving intestinal growth,function,and DNA methylation of the ileum in a porcine IUGR model.Methods Forty multiparous sows were allocated to the control or MET diet groups from mating until delivery.After farrowing,8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling colostrum.Results The results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of piglets.Moreover,maternal MET supplementation significantly reduced the plasma concentrations of isoleucine,cysteine,urea,and total amino acids in sows and newborn pig-lets.It also increased lactase and sucrase activity in the jejunum of newborn piglets.MET addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn piglets.DNA methylation analysis of the ileum showed that MET supplementation increased the methyla-tion level of DNA CpG sites in the ileum of newborn piglets.Down-regulated differentially methylated genes were enriched in folic acid binding,insulin receptor signaling pathway,and endothelial cell proliferation.In contrast,up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosyn-thetic process.Conclusions Maternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets,which may be associated with better intestinal function and methylation status.

Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows

Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracted SBMs from soybeans produced in the USA,Brazil,and China were selected.In Exp.1,eight different diets were created:a nitrogen(N)-free diet and 7 experimental diets containing SBM from different origins as the only N source.Eight non-pregnant,multiparous sows were arranged in an 8×8 Latin square design(8 periods and 8 diets).In Exp.2,the diet formula was the same as in Exp.1.Eight gestating sows(parity 3)were assigned to 4 different diets in a replicated 4×3 Youden square design(three periods and four diets)in mid-gestation and again in late-gestation stages.Results When fed to non-pregnant and late-gestating sows,the standardized ileal digestibility(SID)of CP and most AAs from different SBM were not significantly different(P>0.05).When fed to mid-gestating sows,the SID values for Arg,His,Lys,Phe,Cys,Gly,Ser,and Tyr in SBM 1 were lower than in SBM 4 and 5(P<0.05),whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4(P<0.05).SID values for Ile,Ala,and Asp from SBM 4 were lower than in SBM 1 and 5(P<0.05).Sows had significantly greater SID values for Lys,Ala,and Asp during mid-gestation when compared with late-gestation stages(P<0.05).Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows(P<0.01),whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows(P<0.01).Conclusions When fed to mid-gestating sows,the SID values for most AAs varied among SBM samples.The SID values for Lys,Met,Val,Ala,Asp,and Tyr in SBM were affected by sow gestation stages.Our findings provide a cornerstone for accurate SBM use in sow diets.

Impact of dietary fat levels and fatty acid composition on milk fat synthesis in sows at peak lactation

Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis,and milk fatty acid(FA)output is sparse in sows.This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows.Forty second-parity sows(Danish Landrace×Yorkshire)were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning(d 28 of lactation):low-fat control diet(3%added animal fat);or 1 of 4 high-fat diets with 8%added fat:coconut oil(CO),fish oil(FO),sunflower oil(SO),or 4%octanoic acid plus 4%FO(OFO).Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.Results Daily intake of FA was lowest in low-fat sows within fat levels(P<0.01)and in OFO and FO sows within highfat diets(P<0.01).Daily milk outputs of fat,FA,energy,and FA-derived carbon reflected to a large extent the intake of those.On average,estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo+mobilized FA/d according to method 3.The low-fat diet increased mammary FAS expression(P<0.05)and de novo fat synthesis(method 1;P=0.13)within fat levels.The OFO diet increased de novo fat synthesis(method 1;P<0.05)and numerically upregulated mammary FAS expression compared to the other high-fat diets.Across diets,a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.Conclusions Sows fed diets with low-fat or octanoic acid,through upregulating FAS expression,increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets,indicating that dietary FA intake,dietary fat level,and body fat mobilization in concert determine de novo fat synthesis,amount and profiles of FA in milk.

Dietary fiber during gestation improves lactational feed intake of sows by modulating gut microbiota

Background The feed intake of sows during lactation is often lower than their needs.High-fiber feed is usually used during gestation to increase the voluntary feed intake of sows during lactation.However,the mechanism underlying the effect of bulky diets on the appetites of sows during lactation have not been fully clarified.The current study was conducted to determine whether a high-fiber diet during gestation improves lactational feed intake(LFI)of sows by modulating gut microbiota.Methods We selected an appropriate high-fiber diet during gestation and utilized the fecal microbial transplanta-tion(FMT)method to conduct research on the role of the gut microbiota in feed intake regulation of sows during lactation,as follows:high-fiber(HF)diet during gestation(n=23),low-fiber(LF)diet during gestation(n=23),and low-fiber diet+HF-FMT(LFM)during gestation(n=23).Results Compared with the LF,sows in the HF and LFM groups had a higher LFI,while the sows also had higher peptide tyrosine tyrosine and glucagon-like peptide 1 on d 110 of gestation(G110 d).The litter weight gain of piglets during lactation and weaning weight of piglets from LFM group were higher than LF group.Sows given a HF diet had lower Proteobacteria,especially Escherichia-Shigella,on G110 d and higher Lactobacillus,especially Lactobacil-lus_mucosae_LM1 and Lactobacillus_amylovorus,on d 7 of lactation(L7 d).The abundance of Escherichia-Shigella was reduced by HF-FMT in numerically compared with the LF.In addition,HF and HF-FMT both decreased the perinatal concentrations of proinflammatory factors,such as endotoxin(ET),lipocalin-2(LCN-2),tumor necrosis factor-α(TNF-α),and interleukin-1β(IL-1β).The concentration of ET and LCN-2 and the abundance of Proteobacteria and Escheri-chia-Shigella were negatively correlated with the LFI of sows.Conclusion The high abundance of Proteobacteria,especially Escherichia-Shigella of LF sows in late gestation,led to increased endotoxin levels,which result in inflammatory responses and adverse effects on the LFI of sows.Add-ing HF during gestation reverses this process by increasing the abundance of Lactobacillus,especially Lactobacil-lus_mucosae_LM1 and Lactobacillus_amylovorus.

Maternal organic selenium supplementation during gestation enhances muscle fiber area and muscle fiber maturation of offspring in porcine model

Background:Organic selenium supplementation during gestation improves the antioxidant status and reproduc-tive performance of sows and increases the antioxidative capacity of the intestines of their offspring.This study was conducted to investigate the effect of maternal basel diet(control)supplemented with an organic Se,2-hydroxy-4-methylselenobutanoic acid(HMSeBA),or inorganic sodium selenite(Na_(2)SeO_(3))during gestation on the antioxidant status and development of muscle in newborn and weaned piglets.Newborn piglets before colostrum intake and weaned piglets were selected for longissimus dorsi(LD)muscle collection and analysis.Results:The results showed that maternal HMSeBA supplementation increased the muscle area and content of Se in the LD muscle of newborn piglets,improved gene expression of selenoproteins,and decreased oxidative status in the LD muscle of both newborn and weaned piglets compared with the control.The expression of muscle development-related genes of newborn piglets in the HMSeBA group was lower than in the control group,whereas the expression of MRF4 in weaned piglets was higher in the HMSeBA group than in the control and Na_(2)SeO_(3)groups.In addition,HMSeBA supplementation decreased the mRNA expressions of myosin heavy chains(MyHC)IIx and MyHC IIb and the percentage of MyHC IIb;increased the expression of PGC-1αin the LD muscle of newborn piglets;increased the gene expression of MyHC IIa;and decreased the protein expression of slow MyHC and the activity of malate dehydrogenase in the LD muscle of weaned piglets compared with the control group.Conclusions:Maternal HMSeBA supplementation during gestation can improve the antioxidative capacity of the muscle of their offspring and promote the maturity of muscle fibres in weaned offspring.

浅谈公猪养殖过程中的营养问题

公猪在养猪生产中的重要性日益突出,然而由于人们对公猪营养的研究相对较少,尚有许多问题困扰着行业的发展。文章就养猪生产上十分关注的一些问题进行简单的描述和分析,以为规模化养殖场种公猪营养的制定提供依据和参考。

Effects of dietary Clostridium butyricum supplementation on growth performance,intestinal development,and immune response of weaned piglets challenged with lipopolysaccharide

Background: Weanling pigs, with immature immune system and physiological function, usually experience postweaning diarrhea. This study determined the effects of dietary Clostridium butyricum supplementation on growth performance, diarrhea, and immunity of weaned pigs challenged with lipopolysaccharide(LPS).Methods: In Experiment(Exp.) 1,144 weaned piglets were weaned at 21 d and randomly assigned to six groups,with six replicates per group and four pigs per replicate, receiving a control diet(CON) or diet supplemented with antibiotics(AB) or C. butyricum(CB)(0.1%, 0.2%, 0.4%, or 0.8%), respectively. All diets in Exp. 1 were a highly digestible basal diet, with 3,000 mg/kg zinc oxide supplied in the first 2 wk only. In Exp. 2, 180 piglets were weaned at 21 d and randomly assigned to five groups, with six replicates per group and six pigs per replicate, receiving CON, AB, or CB(0.2%, 0.4%, or 0.6%) diets. The digestibility of diets was lower than those in Exp. 1, and did not include zinc oxide. At 36 d of Exp. 2, 12 piglets were selected from each of the CON and 0.4% CB groups, six piglets were intraperitoneally injected with LPS(50 μg/kg body weight) and the other six piglets with normal saline;animals were killed at 4 h after injection to collect blood, intestine, and digesta samples for biochemical analysis.Results: In Exp. 1, CB and AB diets had no effect on growth performance of piglets. In Exp. 2, 0.4% CB decreased feed-gain ratio(P < 0.1), diarrhea score(P < 0.05), and increased duodenal, jejunal, and ileal villus height and jejunal villus height/crypt depth(P < 0.05). The 0.4% CB decreased the plasma tumor necrosis factor(TNF) α(P < 0.05) but increased ileal mucosa IL-10 and TLR2 mRNA expression(P < 0.05). Furthermore, 0.4% CB altered the microbial profile, with Bacillus and Ruminococcaceae UGG-003 at genus level and Lactobacillus casei and Parasutterella secunda at species level were higher than CON in colonic content(P < 0.05).Conclusions: Dietary C. butyricum supplementation had positive effects on growth of weaned piglets with less digestible diets. There was a tendency to reduce the feed-gain ratio, which could reduce feed costs in pig production. Moreover, C. butyricum decreased post-weaning diarrhea by improving the intestinal morphology,intestinal microflora profile, and immune function.

Enterococcus faecium NCIMB 10415 administration improves the intestinal health and immunity in neonatal piglets infected by enterotoxigenic Escherichia coli K88

Background:This study aimed to investigate the effects of oral administration of Enterococcus faecium NCIMB10415(E.faecium)on intestinal development,immunological parameters and gut microbiota of neonatal piglets challenged with enterotoxigenic Escherichia coli K88(ETEC).A total of 961-day-old sow-reared piglets were randomly assigned to 2 groups,with 48 piglets in each group.The piglets were from 16 litters(6 piglets each litter),and 3 piglets each litter were allocated to the E.faecium-supplemented(PRO)group,while the other 3 piglets were allocated to the control(CON)group.After colostrum intake,piglets in the PRO group were orally administrated with 3×10~9 CFU E.faecium per day for a period of one week.On day 8,one piglet per litter from each group was challenged(CON+ETEC,PRO+ETEC)or not(CON-ETEC,PRO-ETEC)with ETEC in a 2×2 factorial arrangement of treatments.On day 10(2 days after challenge),blood and tissue samples were obtained from piglets.Results:Before ETEC challenge,there were no significant differences for the average daily gain(ADG)and fecal score between the two groups of piglets.After ETEC challenge,the challenged piglets had greater fecal score compared to the non-challenged piglets,whereas E.faecium administration was able to decrease the fecal score.Piglets challenged with ETEC had shorter villous height,deeper crypt depth,and reduced number of goblet cells in the jejunum and decreased m RNA abundance of claudin-1 in the ileum,whereas increased the percentage of lymphocytes,concentrations of IL-1βin the plasma and TNF-αin the ileal mucosa,as well as increased the m RNA abundances of innate immunity-related genes in the ileum tissue.These deleterious effects caused by ETEC were partly alleviated by feeding E.faecium.In addition,piglets in PRO-ETEC group had decreased the percentage of CD8^+T cells of the peripheral blood when compared to those in CON-ETEC group.Moreover,E.faecium administration increased Verrucomicrobia at phylum level and decreased Bilophila at genus level.Conclusions:These results suggest that oral administration of E.faecium alleviated the intestinal injury and diarrhea severity of neonatal piglets challenged by ETEC,partly through improving the intestinal microbiota and immune response.This offers a potential strategy of dietary intervention against intestinal impairment by ETEC in neonatal piglets.

Inclusion of purified dietary fiber during gestation improved the reproductive performance of sows

Background: This study aimed to investigate the impacts of guar gum and cellulose as the source of dietary fiber during gestation on the reproductive performance of sows.Methods: A total of 210 sows(parities 3–6) were randomly allocated into six diets(n = 35) throughout gestation to feed graded levels of dietary fiber(DF), including a corn-soybean meal-based control diet with no wheat bran inclusion(CON, 12.5% DF), a wheat bran-rich diet(DF1, 17.4% DF), and another 4 diets(DF2, 17.7% DF;DF3, 18.1%DF;DF4, 18.4% DF;DF5, 18.8% DF) in which wheat bran were equally substituted by 1%, 2%, 3% and 4% purified FIBER MIX(guar gum and cellulose, 1:4). All sows received similar DE and other nutrients throughout gestation.Results: DF treatment during gestation resulted in normal fecal score(1 to 5 with 1 = dry and 5 = watery) in sows compared with those received the CON diet(P < 0.05). The number of total born piglets had a tendency to be affected by dietary treatment(P = 0.07), and correlation analysis revealed a linear response of total born to dietary fiber levels during gestation(P < 0.01). Sows received the DF2, DF3, and DF5 diets during gestation had a greater ADFI during lactation compared with those in the CON group(P < 0.05) without affecting the daily body weight gain of suckling piglets. Gut microbiota compositions were dramatically changed by the gestation stage and some of those were changed by DF inclusion. Fecal acetate, propionate, and butyrate of sows were markedly increased in late gestation, and butyrate contents in feces of gestating sows were significantly affected by DF levels(P < 0.01).Serum concentrations of pro-inflammatory TNF-α were decreased and anti-inflammatory IL-10 was increased on day30 of gestation by DF levels(P < 0.05).Conclusions: In summary, increasing dietary fiber levels by guar gum and cellulose during gestation improved the reproductive performance of sows, which might be related to changes in immunity and gut microbiota of sows.

Comparative effects of enzymatic soybean,fish meal and milk powder in diets on growth performance,immunological parameters,SCFAs production and gut microbiome of weaned piglets

Background:The objective of this study was to evaluate the replacement effects of milk powder(MK)and fish meal(FM)by enzymatic soybean(ESB)in diets on growth performance,immunological parameters,SCFAs production and gut microbiome of weaned piglets.Methods:A total of 128 piglets with initial body weight at 6.95±0.46 kg,were randomly assigned into 4 dietary treatments with 8 replicates per treatment and 4 piglets per replicate for a period of 14 d.Piglets were offered isonitrogenous and iso-energetic diets as follows:CON diet with MK and FM as high quality protein sources,ESB plus FM diet with ESB replacing MK,ESB plus MK diet with ESB replacing FM,and ESB diet with ESB replacing both MK and FM.Results:No significant differences were observed in growth performance among all treatments(P>0.05).However,piglets fed ESB plus FM or ESB diet had increased diarrhea index(P<0.01),and lower digestibility of dry matter(DM),gross energy(GE)or crude protein(CP),relative to piglets fed CON diet(P<0.01).Moreover,the inclusion of ESB in diet markedly decreased the plasma concentration of HPT and fecal concentration of butyric acid(BA)(P<0.01).The High-throughput sequencing of 16S rRNA gene V3−V4 region of gut microbiome revealed that the inclusion of ESB in diet increased the alpha diversity,and the linear discriminant analysis effect size(LEfSe)showed that piglets fed with ESB plus FM or ESB diet contained more gut pathogenic bacteria,such as g_Peptococcus,g_Veillonella and g_Helicobacter.Conclusion:The inclusion of ESB in diet did not markedly affect growth performance of piglets,but the replacement of MK or both MK and FM by ESB increased diarrhea index,which could be associated with lower nutrients digestibility and more gut pathogenic bacteria.However,piglets fed diet using ESB to replace FM did not markedly affect gut health-related parameters,indicating the potential for replacing FM with ESB in weaning diet.

Microbial and metabolomic mechanisms mediating the effects of dietary inulin and cellulose supplementation on porcine oocyte and uterine development

Background:Dietary fiber(DF)is often eschewed in swine diet due to its anti-nutritional effects,but DF is attracting growing attention for its reproductive benefits.The objective of this study was to investigate the effects of DF intake level on oocyte maturation and uterine development,to determine the optimal DF intake for gilts,and gain microbial and metabolomic insight into the underlying mechanisms involved.Methods:Seventy-six Landrace×Yorkshire(LY)crossbred replacement gilts of similar age(92.6±0.6 d;mean±standard deviation[SD])and body weight(BW,33.8±3.9 kg;mean±SD)were randomly allocated to 4 dietary treatment groups(n=19);a basal diet without extra DF intake(DF 1.0),and 3 dietary groups ingesting an extra50%(DF 1.5),75%(DF 1.75),and 100%(DF 2.0)dietary fiber mixture consisting of inulin and cellulose(1:4).Oocyte maturation and uterine development were assessed on 19 d of the 2nd oestrous cycle.Microbial diversity of faecal samples was analysed by high-throughput pyrosequencing(16S r RNA)and blood samples were subjected to untargeted metabolomics.Results:The rates of oocytes showing first polar bodies after in vitro maturation for 44 h and uterine development increased linearly with increasing DF intake;DF 1.75 gilts had a 19.8%faster oocyte maturation rate and a 48.9 cm longer uterus than DF 1.0 gilts(P<0.05).Among the top 10 microbiota components at the phylum level,8increased linearly with increasing DF level,and the relative abundance of 30 of 53 microbiota components at the genus level(>0.1%)increased linearly or quadratically with increasing DF intake.Untargeted metabolic analysis revealed significant changes in serum metabolites that were closely associated with microbiota,including serotonin,a gut-derived signal that stimulates oocyte maturation.Conclusions:The findings provide evidence of the benefits of increased DF intake by supplementing inulin and cellulose on oocyte maturation and uterine development in gilts,and new microbial and metabolomic insight into the mechanisms mediating the effects of DF on reproductive performance of replacement gilts.

Beneficial effects of a decreased meal frequency on nutrient utilization,secretion of luteinizing hormones and ovarian follicular development in gilts

Background:Replacement gilts are typically fed ad libitum,whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits.The objective of this study was to investigate the effect of meal frequency on the metabolic status and ovarian follicular development in gilts.Methods:A total of 36 gilts(Landrace×Yorkshire)with an age of 150±3 d and a body weight of 77.6±3.8 kg were randomly allocated into one of three groups(n=12 in each group),and based on the group allocation,the gilts were fed at a frequency of one meal(T1),two meals(T2),or six meals per day(T6)for 14 consecutive weeks.The effects of the meal frequency on growth preference,nutrient utilization,short-chain fatty acid production by gut microbial,the post-meal dynamics in the metabolic status,reproductive hormone secretions,and ovarian follicular development in the gilts were measured.Results:The gilts in the T1 group presented a higher average daily gain(+48 g/d,P<0.05)and a higher body weight(+4.9 kg,P<0.05)than those in the T6 group.The meal frequency had no effect on the apparent digestibility of dry matter,crude protein,ether extract,ash,and gross energy,with the exception that the T1 gilts exhibited a greater NDF digestibility than the T6 gilts(P<0.05).The nitrogen balance analysis revealed that the T1 gilts presented decreased urine excretion of nitrogen(−8.17 g/d,P<0.05)and higher nitrogen retention(+9.81 g/d,P<0.05),and thus exhibited higher nitrogen utilization than the T6 gilts.The time-course dynamics of glucose,α-amino nitrogen,urea,lactate,and insulin levels in serum revealed that the T1 group exhibited higher utilization of nutrients after a meal than the T2 or T6 gilts.The T1 gilts also had a higher acetate content and SCFAs in feces than the T6 gilts(P<0.05).The age,body weight and backfat thickness of the gilts at first estrous expression were not affected by the meal frequency,but the gilts in the T1 group had higher levels of serum luteinizing hormone on the 18th day of the 3rd estrus cycle and 17β-estradiol,a larger number of growing follicles and corpora lutea,and higher mRNA expression levels of genes related to follicular development on the 19th day of the 3rd estrus cycle.Conclusions:The current findings revealed the benefits of a lower meal frequency equal feed intake on nutrient utilization and reproductive function in replacement gilts,and thus provide new insights into the nutritional strategy for replacement gilts,and the dietary pattern for other mammals,such as humans.

Transfer of β-hydroxy-β-methylbutyrate from sows to their offspring and its impact on muscle fiber type transformation and performance in pigs

Background： Previous studies suggested that supplementation of lactating sows with β-hydroxy-β-methylbutyrate（HMB） could improve the performance of weaning pigs, but there were little information in the muscle fiber type transformation of the offspring and the subsequent performance in pigs from weaning through finishing in response to maternal HMB consumption. The purpose of this study was to determine the effect of supplementing lactating sows with HMB on skeletal muscle fiber type transformation and growth of the offspring during d 28 and180 after birth. A total of 20 sows according to their body weight were divided into the control（CON, n = 10） or HMB groups（HMB, n = 10）. Sows in the HMB group were supplemented with β-hydroxy-β-methylbutyrate calcium（HMB-Ca） 2 g/kg feed during d 1 to 27 of lactation. After weaning, 48 mixed sex piglets were blocked by sow treatment and fed standard diets for post-weaning, growing, finishing periods. Growth performance was recorded during d 28 to 180 after birth. Pigs were slaughtered on d 28（n = 6/treatment） and 180（n = 6/treatment） postnatal and the longissimus dorsi（LD） was collected, respectively.Results： The HMB-fed sows during lactation showed increased HMB concentration（P ＆lt; 0.05） in milk and LD of weaning piglets（P ＆lt; 0.05）. In addition, offsprings in HMB group had a higher finishing BW and lean percentage than did pigs in CON group（P ＆lt; 0.05）, meanwhile, compared with pigs from sows fed the CON diet, pigs from sows fed HMB diet showed higher type Ⅱ muscle fiber cross-sectional area（CSA）, elevated myosin heavy chain（MyHC） Ⅱb and Sox6 mRNA, and fast-MyHC protein levels in LD（P ＆lt; 0.05）.Conclusions： HMB supplemented to sow diets throughout lactation increases the levels of HMB in maternal milk and skeletal muscle of pigs during d 28 after birth and promotes subsequent performance of pigs between d 28 and 180 of age by enhancing glycolytic muscle fiber transformation.

Mammary cell proliferation and catabolism of adipose tissues in nutrition-restricted lactating sows were associated with extracellular high glutamate levels

Background: Persistent lactation,as the result of mammary cellular anabolism and secreting function,is dependent on substantial mobilization or catabolism of body reserves under nutritional deficiency.However,little is known about the biochemical mechanisms for nutrition-restricted lactating animals to simultaneously maintain the anabolism of mammary cells while catabolism of body reserves.In present study,lactating sows with restricted feed allowance(RFA)(n = 6),24% feed restriction compared with the control(CON) group(n = 6),were used as the nutrition-restricted model.Microdialysis and mammary venous cannulas methods were used to monitor postprandial dynamic changes of metabolites in adipose and mammary tissues.Results: At lactation d 28,the RFA group showed higher(P < 0.05) loss of body weight and backfat than the CON group.Compared with the CON group,the adipose tissue of the RFA group had higher(P < 0.05) extracellular glutamate and insulin levels,increased(P < 0.05) lipolysis related genes(HSL and ATGL) expression,and decreased(P < 0.05) glucose transport and metabolism related genes(VAMP8,PKLR and LDHB) expression.These results indicated that under nutritional restriction,reduced insulin-mediated glucose uptake and metabolism and increased lipolysis in adipose tissues was related to extracellular high glutamate concentration.As for mammary glands,compared with the CON group,the RFA group had up-regulated(P < 0.05) expression of Notch signaling ligand(DLL3) and receptors(NOTCH2 and NOTCH4),higher(P < 0.05) extracellular glutamate concentration,while expression of cell proliferation related genes and concentrations of most metabolites in mammary veins were not different(P > 0.05) between groups.Accordingly,piglet performance and milk yield did not differ(P > 0.05) between groups.It would appear that activation of Notch signaling and adequate supply of glutamate might assist mammogenesis.Conclusions: Mammary cell proliferation and catabolism of adipose tissues in nutrition-restricted lactating sows were associated with extracellular high glutamate levels.

Increased maternal consumption of methionine as its hydroxyl analog promoted neonatal intestinal growth without compromising maternal energy homeostasis

Background： To determine responses of neonatal intestine to maternal increased consumption of DL-methionine（DLM） or DL-2-hydroxy-4-methylthiobutanoic acid（HMTBA）, eighteen primiparous sows（Landrace × Yorkshire） were allocated based on body weight and backfat thickness to the control, DLM and HMTBA groups（n = 6）, with the nutritional treatments introduced from postpartum d0 to d14.Results： The DLM-fed sows showed negative energy balance manifested by lost bodyweight, lower plasma glucose, subdued tricarboxylic acid cycle, and increased plasma lipid metabolites levels. Both villus height and ratio of villus height to crypt depth averaged across the small intestine of piglets were higher in the DLM and HMTBA groups than in the control group. Piglet jejunal oxidized glutathione concentration and ratio of oxidized to reduced glutathione were lower in the HMTBA group than in the DLM and control groups. However, piglet jejunal aminopeptidase A, carnitine transporter 2 and IGF-II precursor m RNA abundances were higher in the DLM group than in the HMTBA and control groups.Conclusion： Increasing maternal consumption of methionine as DLM and HMTBA promoted neonatal intestinal growth by increasing morphological development or up-regulating expression of genes responsible for nutrient metabolism. And increasing maternal consumption of HMTBA promoted neonatal intestinal antioxidant capacity without compromising maternal energy homeostasis during early lactation.

Identification of Epsin1 as a regulator for hepatic lipid and glucose metabolism

Obesity related non-alcoholic fatty liver disease(NAFLD),which can progress to steatohepatitis and insulin resistance,has become a major chronic liver disease worldwide.1 As an adaptor of clathrin-mediated endocytosis,Epsin1 plays a role in many diseases,including tumors,atherosclerosis and diabetic wound healing.

Effects of dietary supplementation with essential oils and protease on growth performance,antioxidation,inflammation and intestinal function of weaned pigs

This experiment evaluated the impacts of essential oils(EO)and protease(PRO),independently or in combination,on growth performance,antioxidation,inflammation and intestinal function of weaned pigs.One hundred and sixty weaned pigs(21 d of age,BW of 6.74±0.20 kg)were randomly divided into 4 treatments with 8 replicate pens of 5 pigs per pen.Dietary treatments included the following:1)control diet(CON),2)CON with 300 mg/kg essential oils(EO),3)CON with 500 mg/kg protease(PRO),4)CON with 300 mg/kg essential oil and 500 mg/kg protease(EO + PRO).On d 8,one pig from each penwas selected for sampling.The remaining pigs were fed for an additional week and growth performance was monitored during this period.Dietary treatments had no marked effects(P>0.05)on the growth performance of pigs.However,pigs receiving EO diet had higher(P<0.05)serumglutathione peroxidase(GSH-Px)activity,and tended to decrease(P=0.063)serum concentration of tumor necrosis factor-a(TNF-a).In addition,pigs receiving EO diet had higher(P<0.05)abundances of phylum Actinobacteria,and genera Bifidobacterium,and lower(P<0.05)phylum Bacteroidetes and genera Alloprevotella in colonic digesta.Pigs receiving PRO diet decreased(P<0.05)the serum concentration of malondialdehyde(MDA)and diamine oxidase activity,increased(P<0.05)the villus height and the ratio of villus height to crypt depth in duodenum,increased sucrase activity in jejunal mucosa,and also increased the abundance of phylum Actinobacteria in colonic digesta.Furthermore,the synergistic effects of EO and PROwas observed(P<0.05)for pigs with decreasing serum TNF-a concentration and increasing serum GSH-Px activity.Collectively,the results indicated that dietary supplementation of EO and PRO had no significant effects on growth performance of weaned pigs.EO diet appeared to improve antioxidant activity and intestinal microbiota,while PRO diet improved intestinal morphology and digestive enzyme activity,and there was a synergistic effect of EO and PRO on reducing inflammatory parameters in weaned pigs.

Dietary supplementation of Bacillus subtilis PB6 improves sow reproductive performance and reduces piglet birth intervals

We investigated the effects of dietary supplementation with Bacillus subtilis PB6(B.subtilis PB6)during late gestation and lactation on sow reproductive performance,antioxidant indices,and gut microbiota.A total of 32 healthy Landrace×Yorkshire sows on d 90 of gestation were randomly assigned to 2 groups,with 16 replicates per group,receiving basal diet(CON)or the basal diet+0.2%B.subtilis PB6,containing 4.0×10^8 CFU/kg of feed(BS).The litter sizes(total born)and numbers of piglets born alive were larger in the BS group(P<0.01),whereas the weights of piglets born alive and the piglet birth intervals were lower in the BS group(P<0.05).Although the litter weights and piglet bodyweights(after crossfostering)were lower after BS treatment(P<0.05),the litter sizes,litter weights,lactation survival rate,and litter weight gains at weaning were higher in BS group(P<0.05).The concentrations of malondialdehyde(MDA)in the sow sera at parturition were lower in the BS group(P<0.01).The serum total antioxidant capacity(T-AOC)at parturition and the serum catalase(CAT)concentrations on d 21 of lactation were higher in the BS group(P<0.05).Dietary supplementation with B.subtilis PB6(P<0.05)reduced the serum endotoxin concentrations in the sows and the serum cortisol concentrations of the piglets at d 14 of lactation.Theα-diversity indices of microbial were higher in the CON group(P<0.05).At the phylum level,B.subtilis PB6 supplementation increased the relative abundances of Gemmatimonadete and Acidobacteria(both P<0.01)and reduced those of Proteobacteria,and Actinobacteria(both P<0.05).At the genus level,B.subtilis PB6 supplementation increased the relative abundance of RuminococcaceaeUCG-013 cc(P<0.05)and reduced that of Streptococcus(P<0.05).This study demonstrated that adding 4.0×10^8 CFU/kg B.subtilis PB6 to sows’feed during late gestation and lactation could shorten piglet birth intervals,enhance the growth performance of suckling piglets,and improve the gut health of sows during late gestation.

Live yeast supplementation during late gestation and lactation affects reproductive performance,colostrum and milk composition,blood biochemical and immunological parameters of sows

This study was conducted to evaluate the effects of dietary live yeast(LY)supplementation during late gestation and lactation on reproductive performance,colostrum and milk composition,blood biochemical and immunological parameters of sows.A total of 40 multiparous sows were randomly fed either the control(CON)diet or the CON diet supplemented with LY at 1 g/kg from d 90 of gestation to weaning.Results showed that the number of stillborn piglets and low BW piglets were significantly decreased in the LY-supplemented sows compared with sows in the CON group(P<0.05).Moreover,the concentrations of protein,lactose and solids-not-fat were increased in the colostrum of LY-supplemented sows(P<0.05).Interestingly,the plasma activities of aspartate aminotransferase(AST),alkaline phosphatase(ALP),gamma-glutamyl transpeptidase(γ-GGT)at d 1 of lactation and alanine aminotransferase(ALT)at weaning day were decreased by feeding LY diet(P<0.05).Meanwhile,sows fed LY diet had higher plasma concentration of immunoglobulin G compared with sows fed CON diet at d 1 of lactation(P<0.05),In conclusion,LY supplementation in maternal diets decreased the number of stillborn piglets and low BW piglets,improved colostrum quality and health status of sows.

Dietary energy intake affects fetal survival and development during early and middle pregnancy in Large White and Meishan gilts

This experiment was designed to determine the effects of variations in dietary energy intake on reproductive performance and gene expression of luteal and endometrium tissues in Large White(LW)and Meishan(MS) gilts during early and middle pregnancy. After insemination, 32 LW gilts were assigned to high and low(HE_Land LE_L, 14.23 and 12.56 MJ DE/kg, respectively) diet treatment groups,while 32 MS gilts were allocated to HE_M and LE_M(12.56 and 10.88 MJ DE/kg) groups. Gilts were slaughtered on days 35, 55 and 90 of gestation. The fetal survival and luteal progesterone(P_4) concentration in the HE_Lgroup were higher on day 35 but lower on day 90 of gestation compared with the LE_L group(P < 0.05) for LW gilts. However, fetal survival and luteal P_4 concentration on day 35 of gestation were greater(P < 0.05) in the LE_M group than in the HE_M group for MS gilts, but no significant difference in mid-gestation was showed. The fetal weights of both breeds were higher for the high energy diets compared with the respective control group on day 90 of gestation(P < 0.05). In addition,the m RNA levels of P_4 synthesis-related proteins had correlated with luteal P_4 concentration in both breeds. Further, endometrial levels of uteroferrin(ACP5), retinol-binding protein 4(RBP_4) and secreted phosphoprotein 1(SPP1) m RNA were upregulated in the HE_Lgroup on day 35 of gestation but ACP5 and SPP1 were downregulated on day 55 of gestation compared with the LE_Lgroup(P < 0.05) for LW gilts. In MS gilts, diet only affected the expression of SPP1(P < 0.05). Our results revealed the differential sensitivity of LW and MS breeds to variations in dietary energy intake. For LW gilts, the HE_Lgroup improved fetal survival on day 35 but a sustained high energy diet decreased fetal survival on day 90 of gestation. The differences in dietary energy intake did not influence fetal survival on day 90 of gestation but the higher energy diet did increase fetal weight in the MS breed compared with the lower energy intake diet. These results may be due to differential luteal secretion activity and endometrium gene expression in these two breeds.