Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and...Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry.展开更多
Background： The protein/energy ratio is important for the production performance and utilization of available feed resources by animals. Increased protein consumption by mammals leads to elevated feed costs and incre...Background： The protein/energy ratio is important for the production performance and utilization of available feed resources by animals. Increased protein consumption by mammals leads to elevated feed costs and increased nitrogen release into the environment. This study aimed to evaluate the effects of dietary protein/energy ratio on the growth performance, carcass traits, meat quality, and plasma metabolites of pigs of different genotypes. Methods： Bama mini-pigs and Landrace pigs were randomly assigned to two dietary treatment groups （Chinese conventional diet with low protein/energy ratio or National Research Council diet with high protein/energy ratio; n = 24 per treatment） in a 2 x 2 factorial arrangement. Blood and muscle samples were collected at the end of the nursery, growing, and finishing phases. Results： We observed significant interactions （P 〈 0.05） between breed and diet for total fat percentage, intramuscular fat （IMF） content, protein content in biceps femoris （BF） muscle, and plasma urea nitrogen （UN） concentration in the nursery phase; for average daily gain （ADG）, average daily feed intake （ADFI）, dry matter, IMF content in psoas major （PM） muscle, and plasma total protein and albumin concentrations in the growing phase; and for drip loss and plasma UN concentration in the finishing phase. Breed influenced （P 〈 0.05） growth performance, carcass traits, and meat quality, but not plasma metabolites. Throughout the trial, Landrace pigs showed significantly higher （P 〈 0.0_5） ADG, ADFI, dressing percentage, lean mass rate, and loin-eye area than did Bama mini-pigs, but significantly lower （P 〈 0.0.5） feed/gain ratio, fat percentage, backfat thickness, and IMF content. Dietary protein/energy ratio influenced the pH value, chemical composition of BF and PM muscles, and plasma activities of glutamic-pyruvic transaminase and gamma-glutamyl transpeptidase, and plasma concentration of UN. Conclusions： Compared with Landrace pigs, Bama mini-pigs showed slower growth and lower carcass performance, but had better meat quality. Moreover, unlike Landrace pigs, the dietary protein/energy ratio did not affect the growth performance of Bama mini-pigs. These results suggest that, in swine production, low dietary protein/energy ratio may be useful for reducing feed costs and minimizing the adverse effects of ammonia release into the environment.展开更多
Background: Pregnancy is associated with important changes in gut microbiota composition. Dietary factors may affect the diversity, composition, and metabolic activity of the intestinal microbiota. Among amino acids, ...Background: Pregnancy is associated with important changes in gut microbiota composition. Dietary factors may affect the diversity, composition, and metabolic activity of the intestinal microbiota. Among amino acids, proline is known to play important roles in protein metabolism and structure, cell differentiation, conceptus growth and development, and gut microbiota re-equilibration in case of dysbiosis.Results: Dietary supplementation with 1% proline decreased(P < 0.05) the amounts of Klebsiella pneumoniae,Peptostreptococcus productus, Pseudomonas, and Veillonella spp. in distal colonic contents than that in the control group. The colonic contents of Butyrivibrio fibrisolvens, Bifidobacterium sp., Clostridium coccoides, Clostridium coccoides-Eubacterium rectale, Clostridium leptum subgroup, Escherichia coli, Faecalibacterium prausnitzii,Fusobacterium prausnitzii, and Prevotella increased(P < 0.05) on d 70 of pregnancy as compared with those on d 45 of pregnancy. The colonic concentrations of acetate, total straight-chain fatty acid, and total short-chain fatty acids(SCFA) in the proline-supplemented group were lower(P < 0.05), and butyrate level(P = 0.06) decreased as compared with the control group. Almost all of the SCFA displayed higher(P < 0.05) concentrations in proximal colonic contents on d 70 of pregnancy than those on d 45 of pregnancy. The concentrations of 1,7-heptyl diamine(P = 0.09) and phenylethylamine(P < 0.05) in proximal colonic contents were higher, while those of spermidine(P = 0.05) and total bioamine(P = 0.06) tended to be lower in the proline-supplemented group than those in the control group. The concentrations of spermidine, spermine, and total bioamine in colonic contents were higher(P < 0.05) on d 70 of pregnancy than those measured on d 45 of pregnancy. In contrast, the concentration of phenylethylamine was lower(P < 0.05) on d 70 than on d 45 of pregnancy.(Continued on next page)(Continued from previous page)Conclusion: These findings indicate that L-proline supplementation modifies both the colonic microbiota composition and the luminal concentrations of several bacterial metabolites. Furthermore, our data show that both the microbiota composition and the concentrations of bacterial metabolites are evolving in the course of pregnancy. These results are discussed in terms of possible implication in terms of luminal environment and consequences for gut physiology and health.展开更多
Background: The interaction of the gut microbiota with key metabolic and physiological processes may be associated with poor growth outcomes in animals born with intrauterine growth restriction(IUGR).Results: Growth p...Background: The interaction of the gut microbiota with key metabolic and physiological processes may be associated with poor growth outcomes in animals born with intrauterine growth restriction(IUGR).Results: Growth performance, plasma hormone concentrations, and intestinal microbiota composition were analyzed in IUGR pigs and in normal birth weight(NBW) pigs when the NBW pigs reached 25, 50, and 100 kg of body weight(BW). Compared to NBW pigs, IUGR pigs had lower initial, weaned, and final BW, and lower average daily gain and average daily feed intake in all the considered time points. In the 25 kg BW group, IUGR pigs had higher concentrations of plasma ghrelin and pancreatic polypeptide(PP), but lower insulin concentration than NBW pigs, while the situation was reversed in the 50 kg BW group. As compared to NBW pigs, IUGR pigs had higher microbial alpha diversity in the jejunum and ileum;in the 50 and 100 kg BW groups, IUGR pigs had higher Firmicutes abundance but lower Proteobacteria abundance in the jejunum, and lower Lactobacillus abundance in the jejunum and ileum;in the 25 kg BW group, IUGR pigs showed higher unclassified Ruminococcaceae abundance in the ileum;and in 25 and 50 kg BW groups, IUGR pigs showed lower Ochrobactrum abundance in the jejunum.Spearman's correlation revealed that Lactobacillus was negatively correlated with growth performance, while unclassified Ruminococcaceae was positively correlated. Predictive metagenomic analysis detected significantly different expression of genes in the intestinal microbiota between IUGR and NBW pigs, suggesting different metabolic capabilities between the two groups.Conclusions: Growing-finishing IUGR pigs showed lower growth performance, higher microbial alpha diversity, and differences in plasma hormone concentrations compared to NBW pigs. Alterations in the abundance of Firmicutes,Proteobacteria, Ruminococcaceae, Lactobacillus, and Ochrobactrum in the small intestine may be associated with IUGR, and may therefore serve as a future target for gut microbiota intervention in growing-finishing IUGR pigs.展开更多
With the widespread ban on the use of antibiotics in swine feed, alternative measures need to be sought to maintain swine health and performance, Antimicrobial peptides （AMPs） are part of the nonspecific defense sys...With the widespread ban on the use of antibiotics in swine feed, alternative measures need to be sought to maintain swine health and performance, Antimicrobial peptides （AMPs） are part of the nonspecific defense system and are natural antibiotics produced by plants, insects, mammalians, and micro-organisms as well as by chemical synthesis. Due to their broad microbicidal activity against various fungi, bacteria and enveloped viruses AMPs are a potential alternative to conventional antibiotics for use in swine production. This review focuses on the structure and mechanism of action of AMPs, as well as their effects on performance, immune function and intestinal health in pigs. The aim is to provide support for the application of AMPs as feed additives replacing antibiotics in swine nutrition.展开更多
Background: Oxidative stress is a key factor that influences piglets' health. Taurine plays an imperative role in keeping the biological system from damage. This study was conducted to investigate the protective e...Background: Oxidative stress is a key factor that influences piglets' health. Taurine plays an imperative role in keeping the biological system from damage. This study was conducted to investigate the protective effect of taurine against muscle injury due to the secondary effect of diquat toxicity.Results: Our study found that taurine effectively and dose-dependently alleviated the diquat toxicity induced rise of feed/gain, with a concurrent improvement of carcass lean percentage. The plasma content of taurine was considerably increased in a dose-dependent manner. Consequently, dietary taurine efficiently improved the activity of plasma antioxidant enzymes. Furthermore, taurine attenuated muscle damage by restoring mitochondrial micromorphology, suppressing protein degradation and reducing the percentage of apoptotic cells in the skeletal muscle. Taurine supplementation also suppressed the genes expression levels of the antioxidant-, mitochondrial biogenesis-, and muscle atrophy-related genes in the skeletal muscle of piglets with oxidative stress.Conclusions: These results showed that the dose of 0.60% taurine supplementation in the diet could attenuate skeletal muscle injury induced by diquat toxicity. It is suggested that taurine could be a potential nutritional intervention strategy to improve growth performance.展开更多
The fertility of sows mainly depends on the embryo losses during gestation and the survival rate of the postfarrowing piglets.The selection of highly-prolific sows has been mainly focused on the selection of genotypes...The fertility of sows mainly depends on the embryo losses during gestation and the survival rate of the postfarrowing piglets.The selection of highly-prolific sows has been mainly focused on the selection of genotypes with high ovulatory quota.However,in the early-and post-implantation stages,the rate of embryo losses was increased with the increase of zygotes.Among the various factors,placental growth and development is the vital determinant for fetal survival,growth,and development.Despite the potential survival of fetuses with deficient placental development,their life-conditions and growth can be damaged by a process termed intrauterine growth retardation(IUGR).The newborn piglets affected by IUGR are prone to increased morbidity and mortality rates;meanwhile,the growth,health and welfare of the surviving piglets will remain hampered by these conditions,with a tendency to exacerbate with age.Functional amino acids such as glycine,proline,and arginine continue to increase with the development of placenta,which are not only essential to placental growth(including vascular growth)and development,but can also be used as substrates for the production of glutathione,polyamines and nitric oxide to benefit placental function in many ways.However,the exact regulation mechanism of these amino acids in placental function has not yet been clarified.In this review,we provide evidence from literature and our own work for the role and mechanism of dietary functional amino acids during pregnancy in regulating the placental functional response to fetal loss and birth weight of piglets.This review will provide novel insights into the response of nutritionally nonessential amino acids(glycine and proline)to placental development as well as feasible strategies to enhance the fertility of sows.展开更多
Background： The current study was carried out to provide a reference for monitory of aflatoxin B_1（AFB_1）,zearalenone（ZEN） and deoxynivalenol（DON） contamination in feed ingredients and complete feeds were colle...Background： The current study was carried out to provide a reference for monitory of aflatoxin B_1（AFB_1）,zearalenone（ZEN） and deoxynivalenol（DON） contamination in feed ingredients and complete feeds were collected from different Province in China from 2013 to 2015.Methods： A total of 443 feed ingredients, including 220 corn, 24 wheat, 24 domestic distillers dried grains with soluble（DDGS）, 55 bran, 20 wheat shorts and red dog, 37 imported DDGS, 34 corn germ meal and 29 soybean meal as well as 127 complete feeds including 25 pig complete feed（powder）, 90 pig complete feed（pellet）, six duck complete feed and six cattle complete feed were randomly collected from different Province in China,respectively, by high-performance chromatography in combined with UV or fluorescence analysis.Results： The incidence rates of AFB_1, ZEN and DON contamination of feed ingredients and complete feeds were80.8, 92.3 and 93.9 %, respectively. The percentage of positive samples for DON ranged from 66.7 to 100 %.Domestic DDGS and imported DDGS presented the most serious contamination AFB_1, ZEN and DON contamination levels of feeds ranged from 61.5 to 100 %, indicated that serious contamination over the studied 3-year period.Conclusion： The current data provide clear evidence that AFB_1, ZEN and DON contamination of feed ingredients and complete feeds in different Province in China is serious and differs over past 3-year. The use of corn, domestic DDGS, imported DDGS and corn germ meal, which may be contaminated with these three mycotoxins, as animal feed may triggered a health risk for animal. Feeds are most contaminated with DON followed by ZEN and AFB_1.Mycotoxins contamination in feed ingredients and complete feeds should be monitored routinely in China.展开更多
Background： To investigate the effects of dietary crude protein（CP） restriction on muscle fiber characteristics and key regulators related to protein deposition in skeletal muscle, a total of 18 growing-finishing p...Background： To investigate the effects of dietary crude protein（CP） restriction on muscle fiber characteristics and key regulators related to protein deposition in skeletal muscle, a total of 18 growing-finishing pigs（62.30 ± 0.88 kg）were allotted to 3 groups and fed with the recommended adequate protein（AP, 16 % CP） diet, moderately restricted protein（MP, 13 % CP） diet and low protein（LP, 10 % CP） diet, respectively. The skeletal muscle of different locations in pigs, including longissimus dorsi muscle（LDM）, psoas major muscle（PMM） and biceps femoris muscle（BFM） were collected and analyzed.Results： Results showed that growing-finishing pigs fed the MP or AP diet improved（P 〈 0.01） the average daily gain and feed： gain ratio compared with those fed the LP diet, and the MP diet tended to increase（P = 0.09） the weight of LDM. Moreover, the ATP content and energy charge value were varied among muscle samples from different locations of pigs fed the reduced protein diets. We also observed that pigs fed the MP diet up-regulated（P 〈 0.05） muscular m RNA expression of all the selected key genes, except that myosin heavy chain（My HC） IIb,My HC IIx, while m RNA expression of ubiquitin ligases genes was not affected by dietary CP level. Additionally, the activation of mammalian target of rapamycin complex 1（m TORC1） pathway was stimulated（P 〈 0.05） in skeletal muscle of the pigs fed the MP or AP diet compared with those fed the LP diet.Conclusion： The results suggest that the pigs fed the MP diet could catch up to the growth performance and the LDM weight of the pigs fed the AP diet, and the underlying mechanism may be partly due to the alteration in energy status, modulation of muscle fiber characteristics and m TORC1 activation as well as its downstream effectors in skeletal muscle of different locations in growing-finishing pigs.展开更多
Background： The intestinal epithelium is an important barrier that depends on a complex mixture of proteins and these proteins comprise different intercellular junctions. The purpose of this study was to investigate ...Background： The intestinal epithelium is an important barrier that depends on a complex mixture of proteins and these proteins comprise different intercellular junctions. The purpose of this study was to investigate the postnatal and developmental changes in morphology, intercellular junctions and voltage-gated potassium（Kv） channels in the intestine of piglets during the suckling and post-weaning periods.Results： Samples of the small intestine were obtained from 1-, 7-, 14-, and 21-d-old suckling piglets and piglets on d 1, 3, 5, and 7 after weaning at 14 d of age. The results showed that the percentage of proliferating cell nuclear antigen（PCNA）-positive cells and alkaline phosphatase（AKP） activity, as well as the abundances of E-cadherin,occludin, and Kv1.5 m RNA and claudin-1, claudin-3, and occludin protein in the jejunum were increased from d 1to d 21 during the suckling period（P 〈 0.05）. Weaning induced decreases in the percentage of PCNA-positive cells,AKP activity and the abundances of E-cadherin, occludin and zonula occludens（ZO）-1 m RNA or protein in the jejunum on d 1, 3 and 5 post-weaning（P 〈 0.05）. There were lower abundances of E-cadherin, occludin and ZO-1m RNA as well as claudin-1, claudin-3 and ZO-1 protein in the jejunum of weanling piglets than in 21-d-old suckling piglets（P 〈 0.05）. The abundances of E-cadherin, occludin, ZO-1 and integrin m RNA were positively related to the percentage of PCNA-positive cells.Conclusion： Weaning at 14 d of age induced damage to the intestinal morphology and barrier. While there was an adaptive restoration on d 7 post-weaning, the measured values did not return to the pre-weaning levels, which reflected the impairment of intercellular junctions and Kv channels.展开更多
The leaves of Eucommia ulmoides are rich in bioactive constituents that have potential gastrointestinal benefits for animals.In aged laying hens,intestinal health issues contribute to a significant decline in egg-layi...The leaves of Eucommia ulmoides are rich in bioactive constituents that have potential gastrointestinal benefits for animals.In aged laying hens,intestinal health issues contribute to a significant decline in egg-laying capacity during intermediate and later stages.It remains unclear whether E.ulmoides leaf extract(ELE)can improve intestinal health and enhance egg production in elderly laying hens,and the underlying mechanisms are yet to be elucidated.Therefore,we conducted a study with 480 laying hens(65 weeks old)randomly allocated into four groups:a control group fed with the basal diet,and three treatment groups supplemented with 500,1,000,and 2,000 mg/kg of ELE,respectively.The primary active constituents of ELE include flavonoids,polysaccharides,terpenoids,and phenolic acids.Dietary supplementation with ELE at 1,000 mg/kg(ELE1000)significantly improved laying performance and egg quality compared to the other groups.ELE1000 stimulated the maturation of intestinal epithelial cells,increased villus height,and reduced crypt depth.It also influenced the levels of proteins associated with tight junctions(claudin-1 and claudin-2)and intestinal inflammatory factors(IL-6,IL-1β,and IL-2)in different intestinal sections.Integrative analysis of serum metabolomics and gut microbiota revealed that ELE1000 improved nutrient metabolism by modulating amino acid and ubiquinone biosynthesis and influenced the abundance of intestinal microbiota by enriching pivotal genera such as Bacteroides and Rikenellaceae_RC9_gut_group.We identified 15 metabolites significantly correlated with both gut microbiota and laying performance,e.g.,DL-methionine sulfoxide,THJ2201 N-valerate metabolite,tetracarbonic acid,etc.In conclusion,ELE1000 improved laying performance in elderly laying hens by affecting intestinal morphology,barrier function,microbiota,and serum metabolite profiles.These findings suggest that ELE can be a beneficial feed additive for extending the peak producing period in aged laying hens.展开更多
Four crossbred （Duroc x Landrace x Yorkshire） boars, weighing an average of 22.40 ± 1.08 kg and fitted with permanent catheters in their portal and mesenteric veins as well as their carotid artery,were utilized...Four crossbred （Duroc x Landrace x Yorkshire） boars, weighing an average of 22.40 ± 1.08 kg and fitted with permanent catheters in their portal and mesenteric veins as well as their carotid artery,were utilized in a 4 × 4 latin square design experiment in order to investigate the effects of different starch sources （maize ,brown rice, sticky rice, and resistant starch） on the absorption of energy sources through the portal vein. Portal blood flow averaged 30.68, 28.40, 29.99, and 30. 12 mL/min per kg BW for pigs fed the maize, brown rice, sticky rice, and resistant starch diets, respectively, and did not dif- fer （P 〉 0.05） between treatments. The absorptions of glucose, plasma ammonia, and total amino acids were significantly lower （P 〈 0.05 ） in pigs fed the resistant starch diet than pigs fed the other starch sources. In contrast, significantly （ P 〈 0.05 ） higher amounts of propionate and total volatile fatty acids were absorbed from the portal vein of pigs fed resistant starch than pigs fed diets based on maize, brown rice, or sticky rice. In addition, significantly （P 〈 0.05） more lactic acid was absorbed from the portal vein by pigs fed the sticky rice diet than pigs fed the other three diets. The energy absorbed from the portal vein in the form of glucose and amino-N as well as the total energy absorbed was significantly （P 〈 0.05） lower in pigs fed the resistant starch diet than pigs fed the other three starch sources. In contrast, the amount of energy absorbed in the form of volatile fatty acids was significantly （P 〈 0.05 ） higher in pigs fed resistance starch than pigs fed the other three starch sources. The total energy absorbed through the portal vein as a percentage of the gross energy and digestible energy consumed in pigs fed maize were 50.8% and 54.6%, respectively, which were significantly （P 〈 0.05 ） higher than the values in pigs fed resistant starch （41.5% and 46.6% respectively）. The results indicate that energy is absorbed in different forms and with different utilization efficiencies in the digestive tract of pigs as a result of feeding different starch sources. Starch sources supplying most of their energy in the form of glucose had higher energy utilization efficiencies, while starch sources supplying most of their energy in the form of volatile fatty acids or lactic acid had lower energy utilization efficiencies.展开更多
This study evaluated the effects of flavonoids from mulberry leaves(FML)on plasma biochemical indices,serum activities of lipid metabolism-related enzymes,fat morphology,fatty acid composition,and lipid metabolism in ...This study evaluated the effects of flavonoids from mulberry leaves(FML)on plasma biochemical indices,serum activities of lipid metabolism-related enzymes,fat morphology,fatty acid composition,and lipid metabolism in different adipose tissues of finishing pigs.We used 120 Chinese hybrid barrows of Berkshire and Bama mini-pigs with an average initial body weight of 45.11±4.23 kg.The pigs were randomly assigned to five treatment groups and fed a control diet based on corn,soybean meal,and wheat bran or a control diet supplemented with 0.02%,0.04%,0.08%,or 0.16%FML.Each experimental group had six replicates(pens),with four pigs per pen.After a 7-d adaptation period,the feeding trial was conducted for 58 d.Blood and adipose tissue samples were collected from 30 pigs(one pig per pen)at the end of the test.The results showed that FML supplementation significantly decreased the feed intake to body gain ratio,the plasma concentrations of total cholesterol and free fatty acids,and the serum activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase(linear or quadratic effects,P<0.05),and decreased the plasma triglyceride concentration(quadratic,P=0.07).Increasing FML supplementation increased the average daily gain and serum activities of lipoprotein lipase(linear and quadratic effects,P<0.05)and adipose triglyceride lipase(linear,P<0.05).Dietary FML supplementation decreased the adipocyte area in the dorsal subcutaneous adipose(DSA)tissue of finishing pigs(linear,P=0.05)and increased the adipocyte area in the visceral adipose tissue(quadratic,P<0.01).Increasing FML supplementation decreased the C20:1 content in DSA,abdominal subcutaneous adipose,and visceral adipose tissues of finishing pigs(P<0.05)and increased the C18:3n3 and n-3 PUFA contents(P<0.05).The lipid metabolism genes were regulated by the PPARγ-LXRa-ABCA1 signaling pathway,and their expressions differed in different adipose tissues.These findings suggest that FML improved growth performance,regulated lipid metabolism,inhibited fat production,and improved fatty acid distribution in the adipose tissue of finishing pigs,thereby improving pig fat's nutritional quality and health value.展开更多
Weaning piglets usually suffer from severe diarrhea(commonly known as postweaning diarrhea,PWD)along with intestinal motility disorder.Intestinal peristalsis is mainly regulated by the longitudinal muscle-myenteric pl...Weaning piglets usually suffer from severe diarrhea(commonly known as postweaning diarrhea,PWD)along with intestinal motility disorder.Intestinal peristalsis is mainly regulated by the longitudinal muscle-myenteric plexus(LM-MP).To understand the relationship between intestinal LM-MP function and the development of PWD,we compared the intestinal electrical activity,and the transcriptional profile of the LM-MP between 21-day-old piglets(just weaned,n=7)and 24-day-old piglets(suffered the most severe weaning stress,n=7).The results showed that 24-day-old piglets exhibited different degrees of diarrhea.A significant increase in the slow-wave frequency in the ileum and colon was observed in 24-day-old piglets,while c-kit expression in the intestinal LM-MPs was significantly decreased,indicating that PWD caused by elevated slow-wave frequency may be associated with loss of c-kit.The real-time quantitative PCR(RT-q PCR)and enzyme-linked immunosorbent assay(ELISA)showed that intestinal LM-MPs in 24-day-old piglets may undergo inflammation and oxidative stress.Significant increases in 8-hydroxy-2′-deoxyguanosine and decreases in thioredoxin suggest that weaning may lead to DNA damage in the LM-MP of 24-day-old piglets.In addition,activating transcription factor 3 was significantly upregulated,indicating nerve damage in the LM-MP of 24-day-old piglets.The transcriptomic results showed that most of the differentially expressed genes in the ileal LM-MP after weaning were downregulated and closely related to the cell cycle process.Subsequent RT-q PCR analysis showed that the relative expression of p21 was upregulated,while the expression of cyclin A2,cyclin B1,and proliferating cell nuclear antigen was downregulated in the ileal and colonic LM-MP of 24-day-old piglets,suggesting that weaning may inhibit cell proliferation and cause G1/S cell cycle arrest in ileal and colonic LM-MP.In conclusion,weaning may lead to cell cycle arrest by causing DNA damage in the LM-MP,impairing intestinal motility regulation,and ultimately leading to diarrhea in piglets.展开更多
In this study,the discrete element software EDEM was applied to establish a simulation model of non-uniform-sized particle units for Broussonetia papyrifera stalks,which aimed to address the low utilization rate of ex...In this study,the discrete element software EDEM was applied to establish a simulation model of non-uniform-sized particle units for Broussonetia papyrifera stalks,which aimed to address the low utilization rate of existing Broussonetia papyrifera harvesting machinery,the significant variation between the simulated model of Broussonetia papyrifera stalks and their actual appearance,as well as the absence of contact parameter calibration.Through a combination of the free-fall collision method,inclined plane sliding method,and inclined plane rolling method,numerical simulation was conducted to analyze the pattern of variations in contact parameters between Broussonetia papyrifera stalks and the steel material of the machinery.Accordingly,these parameters were calibrated.The results showed that the coefficient of restitution between Broussonetia papyrifera stalks and steel materials was 0.321,the static friction factor was 0.589,and the rolling friction factor was 0.078.With the parameters of contact between Broussonetia papyrifera stalks as variables and the experimentally measured pile angle as the objective of optimization,the steepest ascent experiment and the three-factor five-level rotation combination experiment were conducted.In this way,a second-order response model was constructed to analyze the relationship between the contact parameters and the pile angle.Through the optimization analysis of experimental data,it was determined that the coefficient of restitution between Broussonetia papyrifera stalks was 0.21,the static friction factor was 0.24,and the rolling friction factor was 0.03.Furthermore,the calibration results were validated through experimentation to show that the relative error between the obtained pile angle under the context of optimal parameter combination and the actual one was 4.11%.In addition,the relative error of mass flow rate in spiral transport was within a reasonable range,this study lays a foundation both theoretically and statistically for the simulation of contact parameters for Broussonetia papyrifera stalk harvesting processing,mechanical harvesting,and so on.展开更多
This study aimed to determine the regulatory mechanism of dietary zinc lactate(ZL)supplementation on intestinal oxidative stress damage in a paraquat(PQ)-induced piglet model.Twenty-eight piglets(mean body weight 9.51...This study aimed to determine the regulatory mechanism of dietary zinc lactate(ZL)supplementation on intestinal oxidative stress damage in a paraquat(PQ)-induced piglet model.Twenty-eight piglets(mean body weight 9.51±0.23 kg)weaned at 28 d of age were randomly divided into control,ZL,PQ,and ZL+PQ groups(n=7 in each group).The ZL-supplemented diet had little effect on growth performance under normal physiological conditions.However,under PQ challenge,ZL supplementation significantly improved average daily gain(P<0.05)and reduced the frequency of diarrhea.ZL improved intestinal morphology and ultrastructure by significantly increasing the expression level of the jejunal tight junction protein,zonula occludens-1(ZO-1)(P<0.05),and intestinal zinc transport and absorption in PQ-induced piglets,which reduced intestinal permeability.ZL supplementation also enhanced the expression of antioxidant and antiinflammatory factor-related genes and decreased inflammatory cytokine expression and secretion in PQinduced piglets.Furthermore,ZL treatment significantly inhibited the activation of constitutive androstane receptor(CAR)signaling(P<0.01)in PQ-induced piglets and altered the structure of the gut microbiota,especially by significantly increasing the abundance of beneficial gut microbes,including UCG_002,Ruminococcus,Rikenellaceae_RC9_gut_group,Christensenellaceae_R_7_group,Treponema,unclassified_Christensenellaceae,and unclassified_Erysipelotrichaceae(P<0.05).These data reveal that pre-administration of ZL to piglets can suppress intestinal oxidative stress by improving antioxidant and anti-inflammatory capacity and regulating the crosstalk between CAR signaling and gut microbiota.展开更多
The objective of this study was to examine the early serum proteomic and inflammatory profiles of weaned piglets subjected to iron deficiency.Twelve healthy piglets(Duroc×Landrace×Large Yorkshire,body weight...The objective of this study was to examine the early serum proteomic and inflammatory profiles of weaned piglets subjected to iron deficiency.Twelve healthy piglets(Duroc×Landrace×Large Yorkshire,body weight:4.96±0.05 kg)were weaned at 21 days of age.Subsequently,these animals were randomly allocated to one of two groups,with six replicates in each group(maintaining a male-to-female ratio of 1:1),the control group(administered 100 mg/kg Fe as FeSO_(4)·H_(2)O)and L-Fe group(no additional Fe supplementation).The results showed that 42 days after initiating,compared with control group,routine blood analysis revealed a reduction in serum iron content,red blood cell(RBC)count,hemoglobin(HGB)content,hematocrit(HCT),and mean corpuscular volume(MCV)(P 0.05).During the early stages of iron deficiency,piglets exhibited increased villus height(VH)and the ratio of VH to crypt depth(CD)in the duodenum(P<0.05)and increased expression levels of iron transporters,including duodenal cytochrome(Cybrd),divalent metal transport 1(DMT1),and ferritin light chain(FTL)(P<0.05).Subsequently,isobaric tags for relative and absolute quantitation(iTRAQ)were used to identify serum proteins.Gene Ontology(GO)analysis of the differentially abundant proteins(DAP)revealed that 24 of the 30 DAP were involved in platelet function,immune response,cellular metabolism,transcription,and protein synthesis.Notably,prothrombin,asporin(ASPN),and Rac family small GTPase 3(RAC3)expression was induced,whereas glycoprotein Ib platelet subunit alpha(GPIbA)expression was decreased.This was accompanied by a substantial reduction in serum complement 3(C3)and complement 4(C4)contents(P<0.05),with elevated the contents of interleukin-1β(IL-1β),interleukin-4(IL-4),interleukin-6(IL-6),transforming growth factor-β1(TGF-β1),and tumor necrosis factor-α(TNF-α)(P<0.05).Our findings underscore the essential role of dietary iron supplementation in maintaining iron homeostasis and modulating inflammatory responses in piglets.展开更多
Excitatory amino acid transporters(EAATs) are responsible for excitatory amino acid transportation and are associated with auto-immune diseases in the central nervous system and peripheral tissues.However, the subcell...Excitatory amino acid transporters(EAATs) are responsible for excitatory amino acid transportation and are associated with auto-immune diseases in the central nervous system and peripheral tissues.However, the subcellular location and function of EAAT2 in macrophages are still obscure. In this study,we demonstrated that LPS stimulation increases expression of EAAT2(coded by Slc1a2) via NF-κB signaling. EAAT2 is necessary for inflammatory macrophage polarization through sustaining mTORC1 activation. Mechanistically, lysosomal EAAT2 mediates lysosomal glutamate and aspartate efflux to maintain V-ATPase activation, which sustains macropinocytosis and mTORC1. We also found that mice with myeloid depletion of Slc1a2 show alleviated inflammatory responses in LPS-induced systemic inflammation and high-fat diet induced obesity. Notably, patients with type Ⅱ diabetes(T2D) have a higher level of expression of lysosomal EAAT2 and activation of mTORC1 in blood macrophages. Taken together, our study links the subcellular location of amino acid transporters with the fate decision of immune cells,which provides potential therapeutic targets for the treatment of inflammatory diseases.展开更多
We previously demonstrated that lipopolysaccharide(LPS)injection-induced immune stress could impair muscle growth in weaned piglets,but the precise mechanisms behind this remain elusive.Here,we found that chronic immu...We previously demonstrated that lipopolysaccharide(LPS)injection-induced immune stress could impair muscle growth in weaned piglets,but the precise mechanisms behind this remain elusive.Here,we found that chronic immune stress induced by LPS resulted in a significant reduction of 36.86%in the total muscle mass of piglets at 5 d post-treatment compared with the control group.At 1 d,prior to muscle mass loss,multiple alterations were noted in response to LPS treatment.These included a reduction in the abundance of Bacteroidetes,an increase in serum concentrations of pro-inflammatory cytokines,compromised mitochondrial morphology,and an upregulation in the expression of dynamin-related protein 1(Drp1),a critical protein involved in mitochondrial fission.We highlight a strong negative correlation between Bacteroidetes abundance and the levels of serum pro-inflammatory cytokines,corroborated by in vivo intervention strategies in the musculature of both pig and mouse models.Mechanistically,the effects of Bacteroidetes on inflammation and muscle mass loss may involve the signaling pathway of the tauro-β-muricholic acid-fibroblast growth factor 15.Furthermore,the induction of overexpression of inflammatory cytokines,achieved without LPS treatment through oral administration of recombinant human IL-6(rh IL-6),led to increased levels of circulating cytokines,subsequently causing a decrease in muscle mass.Notably,pre-treatment with Mdivi-1,an inhibitor of Drp-1,markedly attenuated the LPS-induced elevation in reactive oxygen species levels and rescued the associated decline in muscle mass.Collectively,these data indicate that LPS-induced muscle mass loss was linked to the reduction of Bacteroidetes abundance,increased inflammation,and the disruption of mitochondrial morphology.These insights offer promising avenues for the identification of potential therapeutic targets aimed at mitigating muscle mass loss.展开更多
基金supported by Postdoctoral Innovation Talents’ Support Programthe National Natural Science Foundation of China (32130099)+1 种基金the Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project (TSBICIP-CXRC-038)Laboratory of Lingnan Modern Agriculture Project (NT2021005)。
文摘Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry.
文摘为了比较分析宁乡猪皮下脂肪(subcutaneous fat,SAF)和肌内脂肪(intramuscular fat,IMF)组织脂肪沉积的分子机制,本文利用RNA-seq技术鉴定和分析宁乡猪SAF和IMF组织中差异基因表达谱。选取6头250日龄健康状况良好、种内个体体重相近(约85 kg)的雄性宁乡猪为实验材料,采集SAF与IMF组织样品。通过对两个脂肪组织转录组测序并进行GO(Gene Ontology)功能注释及KEGG(Kyoto Encyclopedia of Genes and Genomes)信号通路富集分析,得到与脂肪沉积和脂质代谢相关的差异基因。为验证测序数据结果的可靠性,本研究随机选取6个差异基因进行qRT-PCR验证。结果表明,宁乡猪SAF和IMF组织中有2406个基因差异表达,其中1422个基因表达上调,984个基因表达下调。通过GO功能注释分析发现,差异表达基因主要通过参与类固醇生物合成、不饱和脂肪酸的生物合成、甘油磷脂代谢及自噬途径等与脂质代谢相关途径,调控宁乡猪SAF和IMF的沉积。KEGG通路富集结果显示,差异基因主要富集在脂质结合、脂肪酸代谢过程、甘油酯代谢过程、脂类生物合成等与脂质代谢相关的生物学过程。qRT-PCR结果与测序结果一致,表明测序结果可靠。通过对宁乡猪SAF与IMF组织进行转录组测序以及生物信息学分析,筛选到TCAP、NR4A1、ACACA、LPL、ELOVL6、DGAT1、PRKAA1、ATG101、TP53INP2、FDFT1、ACOX1和SCD等基因与脂质代谢相关,这些基因可能在宁乡猪SAF与IMF组织中脂肪沉积和代谢过程发挥重要调控作用,对进一步研究宁乡猪脂肪沉积机制具有重要意义。
基金supported by the National Basic Research Program of China(No.2012CB124704 and 2013CB127305)KC.Wong Education Foundation,Hong Kong
文摘Background： The protein/energy ratio is important for the production performance and utilization of available feed resources by animals. Increased protein consumption by mammals leads to elevated feed costs and increased nitrogen release into the environment. This study aimed to evaluate the effects of dietary protein/energy ratio on the growth performance, carcass traits, meat quality, and plasma metabolites of pigs of different genotypes. Methods： Bama mini-pigs and Landrace pigs were randomly assigned to two dietary treatment groups （Chinese conventional diet with low protein/energy ratio or National Research Council diet with high protein/energy ratio; n = 24 per treatment） in a 2 x 2 factorial arrangement. Blood and muscle samples were collected at the end of the nursery, growing, and finishing phases. Results： We observed significant interactions （P 〈 0.05） between breed and diet for total fat percentage, intramuscular fat （IMF） content, protein content in biceps femoris （BF） muscle, and plasma urea nitrogen （UN） concentration in the nursery phase; for average daily gain （ADG）, average daily feed intake （ADFI）, dry matter, IMF content in psoas major （PM） muscle, and plasma total protein and albumin concentrations in the growing phase; and for drip loss and plasma UN concentration in the finishing phase. Breed influenced （P 〈 0.05） growth performance, carcass traits, and meat quality, but not plasma metabolites. Throughout the trial, Landrace pigs showed significantly higher （P 〈 0.0_5） ADG, ADFI, dressing percentage, lean mass rate, and loin-eye area than did Bama mini-pigs, but significantly lower （P 〈 0.0.5） feed/gain ratio, fat percentage, backfat thickness, and IMF content. Dietary protein/energy ratio influenced the pH value, chemical composition of BF and PM muscles, and plasma activities of glutamic-pyruvic transaminase and gamma-glutamyl transpeptidase, and plasma concentration of UN. Conclusions： Compared with Landrace pigs, Bama mini-pigs showed slower growth and lower carcass performance, but had better meat quality. Moreover, unlike Landrace pigs, the dietary protein/energy ratio did not affect the growth performance of Bama mini-pigs. These results suggest that, in swine production, low dietary protein/energy ratio may be useful for reducing feed costs and minimizing the adverse effects of ammonia release into the environment.
基金jointly supported by grants from the National Nature Science Foundation of China(31572421 and 31270044)National Key R&D Program(2017YFD0500503)“Western Light”key program for Talent Cultivation from Chinese Academy of Sciences,and Chinese Academy of Sciences Visiting Professorship for Senior International Scientists(F.Blachier,2013T2S0014)
文摘Background: Pregnancy is associated with important changes in gut microbiota composition. Dietary factors may affect the diversity, composition, and metabolic activity of the intestinal microbiota. Among amino acids, proline is known to play important roles in protein metabolism and structure, cell differentiation, conceptus growth and development, and gut microbiota re-equilibration in case of dysbiosis.Results: Dietary supplementation with 1% proline decreased(P < 0.05) the amounts of Klebsiella pneumoniae,Peptostreptococcus productus, Pseudomonas, and Veillonella spp. in distal colonic contents than that in the control group. The colonic contents of Butyrivibrio fibrisolvens, Bifidobacterium sp., Clostridium coccoides, Clostridium coccoides-Eubacterium rectale, Clostridium leptum subgroup, Escherichia coli, Faecalibacterium prausnitzii,Fusobacterium prausnitzii, and Prevotella increased(P < 0.05) on d 70 of pregnancy as compared with those on d 45 of pregnancy. The colonic concentrations of acetate, total straight-chain fatty acid, and total short-chain fatty acids(SCFA) in the proline-supplemented group were lower(P < 0.05), and butyrate level(P = 0.06) decreased as compared with the control group. Almost all of the SCFA displayed higher(P < 0.05) concentrations in proximal colonic contents on d 70 of pregnancy than those on d 45 of pregnancy. The concentrations of 1,7-heptyl diamine(P = 0.09) and phenylethylamine(P < 0.05) in proximal colonic contents were higher, while those of spermidine(P = 0.05) and total bioamine(P = 0.06) tended to be lower in the proline-supplemented group than those in the control group. The concentrations of spermidine, spermine, and total bioamine in colonic contents were higher(P < 0.05) on d 70 of pregnancy than those measured on d 45 of pregnancy. In contrast, the concentration of phenylethylamine was lower(P < 0.05) on d 70 than on d 45 of pregnancy.(Continued on next page)(Continued from previous page)Conclusion: These findings indicate that L-proline supplementation modifies both the colonic microbiota composition and the luminal concentrations of several bacterial metabolites. Furthermore, our data show that both the microbiota composition and the concentrations of bacterial metabolites are evolving in the course of pregnancy. These results are discussed in terms of possible implication in terms of luminal environment and consequences for gut physiology and health.
基金jointly supported by the National Natural Science Foundation of China (31772613 and 31572421)Special Funds for Construction of Innovative Provinces in Hunan Province (2019RS3022)。
文摘Background: The interaction of the gut microbiota with key metabolic and physiological processes may be associated with poor growth outcomes in animals born with intrauterine growth restriction(IUGR).Results: Growth performance, plasma hormone concentrations, and intestinal microbiota composition were analyzed in IUGR pigs and in normal birth weight(NBW) pigs when the NBW pigs reached 25, 50, and 100 kg of body weight(BW). Compared to NBW pigs, IUGR pigs had lower initial, weaned, and final BW, and lower average daily gain and average daily feed intake in all the considered time points. In the 25 kg BW group, IUGR pigs had higher concentrations of plasma ghrelin and pancreatic polypeptide(PP), but lower insulin concentration than NBW pigs, while the situation was reversed in the 50 kg BW group. As compared to NBW pigs, IUGR pigs had higher microbial alpha diversity in the jejunum and ileum;in the 50 and 100 kg BW groups, IUGR pigs had higher Firmicutes abundance but lower Proteobacteria abundance in the jejunum, and lower Lactobacillus abundance in the jejunum and ileum;in the 25 kg BW group, IUGR pigs showed higher unclassified Ruminococcaceae abundance in the ileum;and in 25 and 50 kg BW groups, IUGR pigs showed lower Ochrobactrum abundance in the jejunum.Spearman's correlation revealed that Lactobacillus was negatively correlated with growth performance, while unclassified Ruminococcaceae was positively correlated. Predictive metagenomic analysis detected significantly different expression of genes in the intestinal microbiota between IUGR and NBW pigs, suggesting different metabolic capabilities between the two groups.Conclusions: Growing-finishing IUGR pigs showed lower growth performance, higher microbial alpha diversity, and differences in plasma hormone concentrations compared to NBW pigs. Alterations in the abundance of Firmicutes,Proteobacteria, Ruminococcaceae, Lactobacillus, and Ochrobactrum in the small intestine may be associated with IUGR, and may therefore serve as a future target for gut microbiota intervention in growing-finishing IUGR pigs.
基金supported by the National Natural Science Foundation of China(No.3133007531372326)
文摘With the widespread ban on the use of antibiotics in swine feed, alternative measures need to be sought to maintain swine health and performance, Antimicrobial peptides （AMPs） are part of the nonspecific defense system and are natural antibiotics produced by plants, insects, mammalians, and micro-organisms as well as by chemical synthesis. Due to their broad microbicidal activity against various fungi, bacteria and enveloped viruses AMPs are a potential alternative to conventional antibiotics for use in swine production. This review focuses on the structure and mechanism of action of AMPs, as well as their effects on performance, immune function and intestinal health in pigs. The aim is to provide support for the application of AMPs as feed additives replacing antibiotics in swine nutrition.
基金supported by the National Key R&D Program(2018YFD0500405)the National Nature Science Foundation of China(31972582)+3 种基金the Science and technology projects of Changsha City(kq1801059)the STS regional key projects of Chinese Academy of Sciences(KFJ-STS-QYZD-052)the Youth Innovation Team Project of ISA,CAS(2017QNCXTD_ZCS)the Earmarked Fund for China Agriculture Research System (CARS-35)。
文摘Background: Oxidative stress is a key factor that influences piglets' health. Taurine plays an imperative role in keeping the biological system from damage. This study was conducted to investigate the protective effect of taurine against muscle injury due to the secondary effect of diquat toxicity.Results: Our study found that taurine effectively and dose-dependently alleviated the diquat toxicity induced rise of feed/gain, with a concurrent improvement of carcass lean percentage. The plasma content of taurine was considerably increased in a dose-dependent manner. Consequently, dietary taurine efficiently improved the activity of plasma antioxidant enzymes. Furthermore, taurine attenuated muscle damage by restoring mitochondrial micromorphology, suppressing protein degradation and reducing the percentage of apoptotic cells in the skeletal muscle. Taurine supplementation also suppressed the genes expression levels of the antioxidant-, mitochondrial biogenesis-, and muscle atrophy-related genes in the skeletal muscle of piglets with oxidative stress.Conclusions: These results showed that the dose of 0.60% taurine supplementation in the diet could attenuate skeletal muscle injury induced by diquat toxicity. It is suggested that taurine could be a potential nutritional intervention strategy to improve growth performance.
基金jointly supported by the National Key R&D Program of China (2021YFD1300401)National Natural Science Foundation of China(31902165)Natural Science Foundation of Guangdong Province(2021A1515012116)
文摘The fertility of sows mainly depends on the embryo losses during gestation and the survival rate of the postfarrowing piglets.The selection of highly-prolific sows has been mainly focused on the selection of genotypes with high ovulatory quota.However,in the early-and post-implantation stages,the rate of embryo losses was increased with the increase of zygotes.Among the various factors,placental growth and development is the vital determinant for fetal survival,growth,and development.Despite the potential survival of fetuses with deficient placental development,their life-conditions and growth can be damaged by a process termed intrauterine growth retardation(IUGR).The newborn piglets affected by IUGR are prone to increased morbidity and mortality rates;meanwhile,the growth,health and welfare of the surviving piglets will remain hampered by these conditions,with a tendency to exacerbate with age.Functional amino acids such as glycine,proline,and arginine continue to increase with the development of placenta,which are not only essential to placental growth(including vascular growth)and development,but can also be used as substrates for the production of glutathione,polyamines and nitric oxide to benefit placental function in many ways.However,the exact regulation mechanism of these amino acids in placental function has not yet been clarified.In this review,we provide evidence from literature and our own work for the role and mechanism of dietary functional amino acids during pregnancy in regulating the placental functional response to fetal loss and birth weight of piglets.This review will provide novel insights into the response of nutritionally nonessential amino acids(glycine and proline)to placental development as well as feasible strategies to enhance the fertility of sows.
基金supported by the Province Science and Technology Major Project of the Department of Science&Technology of Hunan Province(2015NK1002)Changsha City Science and Technology Program of China(k1508008-21)+1 种基金National Key R&D Program(2016YFD0501208)the National Natural Science Foundation of China(31402088,31501964 and31402091)
文摘Background： The current study was carried out to provide a reference for monitory of aflatoxin B_1（AFB_1）,zearalenone（ZEN） and deoxynivalenol（DON） contamination in feed ingredients and complete feeds were collected from different Province in China from 2013 to 2015.Methods： A total of 443 feed ingredients, including 220 corn, 24 wheat, 24 domestic distillers dried grains with soluble（DDGS）, 55 bran, 20 wheat shorts and red dog, 37 imported DDGS, 34 corn germ meal and 29 soybean meal as well as 127 complete feeds including 25 pig complete feed（powder）, 90 pig complete feed（pellet）, six duck complete feed and six cattle complete feed were randomly collected from different Province in China,respectively, by high-performance chromatography in combined with UV or fluorescence analysis.Results： The incidence rates of AFB_1, ZEN and DON contamination of feed ingredients and complete feeds were80.8, 92.3 and 93.9 %, respectively. The percentage of positive samples for DON ranged from 66.7 to 100 %.Domestic DDGS and imported DDGS presented the most serious contamination AFB_1, ZEN and DON contamination levels of feeds ranged from 61.5 to 100 %, indicated that serious contamination over the studied 3-year period.Conclusion： The current data provide clear evidence that AFB_1, ZEN and DON contamination of feed ingredients and complete feeds in different Province in China is serious and differs over past 3-year. The use of corn, domestic DDGS, imported DDGS and corn germ meal, which may be contaminated with these three mycotoxins, as animal feed may triggered a health risk for animal. Feeds are most contaminated with DON followed by ZEN and AFB_1.Mycotoxins contamination in feed ingredients and complete feeds should be monitored routinely in China.
基金financially supported by the National Basic Research Program of China(2013CB127305)the Nature Science Foundation of Hunan Province(S2014J504I)+1 种基金the Major Project of Hunan Province(2015NK1002)the National Science and Technology Ministry(2014BAD08B11)
文摘Background： To investigate the effects of dietary crude protein（CP） restriction on muscle fiber characteristics and key regulators related to protein deposition in skeletal muscle, a total of 18 growing-finishing pigs（62.30 ± 0.88 kg）were allotted to 3 groups and fed with the recommended adequate protein（AP, 16 % CP） diet, moderately restricted protein（MP, 13 % CP） diet and low protein（LP, 10 % CP） diet, respectively. The skeletal muscle of different locations in pigs, including longissimus dorsi muscle（LDM）, psoas major muscle（PMM） and biceps femoris muscle（BFM） were collected and analyzed.Results： Results showed that growing-finishing pigs fed the MP or AP diet improved（P 〈 0.01） the average daily gain and feed： gain ratio compared with those fed the LP diet, and the MP diet tended to increase（P = 0.09） the weight of LDM. Moreover, the ATP content and energy charge value were varied among muscle samples from different locations of pigs fed the reduced protein diets. We also observed that pigs fed the MP diet up-regulated（P 〈 0.05） muscular m RNA expression of all the selected key genes, except that myosin heavy chain（My HC） IIb,My HC IIx, while m RNA expression of ubiquitin ligases genes was not affected by dietary CP level. Additionally, the activation of mammalian target of rapamycin complex 1（m TORC1） pathway was stimulated（P 〈 0.05） in skeletal muscle of the pigs fed the MP or AP diet compared with those fed the LP diet.Conclusion： The results suggest that the pigs fed the MP diet could catch up to the growth performance and the LDM weight of the pigs fed the AP diet, and the underlying mechanism may be partly due to the alteration in energy status, modulation of muscle fiber characteristics and m TORC1 activation as well as its downstream effectors in skeletal muscle of different locations in growing-finishing pigs.
基金funded by the National Key Basic Research Program of China(2013CB127302)National Natural Science Foundation of China(31330075,31372326,31301988,31301989)+4 种基金the State Key Laboratory of Animal Nutrition(2004DA125184F1401)the Spark Program of Jiangxi Province(20142BBF061051)Changsha Lvye Biotechnology Limited Company Academician Expert WorkstationGuangdong Wangda Group Academician Workstation for Clean Feed Technology Research and Development in SwineGuangdong Hinapharm Group Academician Workstation for Biological Feed and Feed Additives and Animal Intestinal Health
文摘Background： The intestinal epithelium is an important barrier that depends on a complex mixture of proteins and these proteins comprise different intercellular junctions. The purpose of this study was to investigate the postnatal and developmental changes in morphology, intercellular junctions and voltage-gated potassium（Kv） channels in the intestine of piglets during the suckling and post-weaning periods.Results： Samples of the small intestine were obtained from 1-, 7-, 14-, and 21-d-old suckling piglets and piglets on d 1, 3, 5, and 7 after weaning at 14 d of age. The results showed that the percentage of proliferating cell nuclear antigen（PCNA）-positive cells and alkaline phosphatase（AKP） activity, as well as the abundances of E-cadherin,occludin, and Kv1.5 m RNA and claudin-1, claudin-3, and occludin protein in the jejunum were increased from d 1to d 21 during the suckling period（P 〈 0.05）. Weaning induced decreases in the percentage of PCNA-positive cells,AKP activity and the abundances of E-cadherin, occludin and zonula occludens（ZO）-1 m RNA or protein in the jejunum on d 1, 3 and 5 post-weaning（P 〈 0.05）. There were lower abundances of E-cadherin, occludin and ZO-1m RNA as well as claudin-1, claudin-3 and ZO-1 protein in the jejunum of weanling piglets than in 21-d-old suckling piglets（P 〈 0.05）. The abundances of E-cadherin, occludin, ZO-1 and integrin m RNA were positively related to the percentage of PCNA-positive cells.Conclusion： Weaning at 14 d of age induced damage to the intestinal morphology and barrier. While there was an adaptive restoration on d 7 post-weaning, the measured values did not return to the pre-weaning levels, which reflected the impairment of intercellular junctions and Kv channels.
基金supported by National Key R&D Program of China(2021YFD1301002)Cooperation project of the Chinese Academy of Science and local governments(2020111)+2 种基金Basic Research and talent Research Fund of Jiangxi Academy of Sciences(2023YJC2003)Central Government Guide Local Science and Technology development Fund Project of Henan Province(Z20221343004)Henan Ground Biological Science&Technology Co.,Ltd.
文摘The leaves of Eucommia ulmoides are rich in bioactive constituents that have potential gastrointestinal benefits for animals.In aged laying hens,intestinal health issues contribute to a significant decline in egg-laying capacity during intermediate and later stages.It remains unclear whether E.ulmoides leaf extract(ELE)can improve intestinal health and enhance egg production in elderly laying hens,and the underlying mechanisms are yet to be elucidated.Therefore,we conducted a study with 480 laying hens(65 weeks old)randomly allocated into four groups:a control group fed with the basal diet,and three treatment groups supplemented with 500,1,000,and 2,000 mg/kg of ELE,respectively.The primary active constituents of ELE include flavonoids,polysaccharides,terpenoids,and phenolic acids.Dietary supplementation with ELE at 1,000 mg/kg(ELE1000)significantly improved laying performance and egg quality compared to the other groups.ELE1000 stimulated the maturation of intestinal epithelial cells,increased villus height,and reduced crypt depth.It also influenced the levels of proteins associated with tight junctions(claudin-1 and claudin-2)and intestinal inflammatory factors(IL-6,IL-1β,and IL-2)in different intestinal sections.Integrative analysis of serum metabolomics and gut microbiota revealed that ELE1000 improved nutrient metabolism by modulating amino acid and ubiquinone biosynthesis and influenced the abundance of intestinal microbiota by enriching pivotal genera such as Bacteroides and Rikenellaceae_RC9_gut_group.We identified 15 metabolites significantly correlated with both gut microbiota and laying performance,e.g.,DL-methionine sulfoxide,THJ2201 N-valerate metabolite,tetracarbonic acid,etc.In conclusion,ELE1000 improved laying performance in elderly laying hens by affecting intestinal morphology,barrier function,microbiota,and serum metabolite profiles.These findings suggest that ELE can be a beneficial feed additive for extending the peak producing period in aged laying hens.
文摘Four crossbred （Duroc x Landrace x Yorkshire） boars, weighing an average of 22.40 ± 1.08 kg and fitted with permanent catheters in their portal and mesenteric veins as well as their carotid artery,were utilized in a 4 × 4 latin square design experiment in order to investigate the effects of different starch sources （maize ,brown rice, sticky rice, and resistant starch） on the absorption of energy sources through the portal vein. Portal blood flow averaged 30.68, 28.40, 29.99, and 30. 12 mL/min per kg BW for pigs fed the maize, brown rice, sticky rice, and resistant starch diets, respectively, and did not dif- fer （P 〉 0.05） between treatments. The absorptions of glucose, plasma ammonia, and total amino acids were significantly lower （P 〈 0.05 ） in pigs fed the resistant starch diet than pigs fed the other starch sources. In contrast, significantly （ P 〈 0.05 ） higher amounts of propionate and total volatile fatty acids were absorbed from the portal vein of pigs fed resistant starch than pigs fed diets based on maize, brown rice, or sticky rice. In addition, significantly （P 〈 0.05） more lactic acid was absorbed from the portal vein by pigs fed the sticky rice diet than pigs fed the other three diets. The energy absorbed from the portal vein in the form of glucose and amino-N as well as the total energy absorbed was significantly （P 〈 0.05） lower in pigs fed the resistant starch diet than pigs fed the other three starch sources. In contrast, the amount of energy absorbed in the form of volatile fatty acids was significantly （P 〈 0.05 ） higher in pigs fed resistance starch than pigs fed the other three starch sources. The total energy absorbed through the portal vein as a percentage of the gross energy and digestible energy consumed in pigs fed maize were 50.8% and 54.6%, respectively, which were significantly （P 〈 0.05 ） higher than the values in pigs fed resistant starch （41.5% and 46.6% respectively）. The results indicate that energy is absorbed in different forms and with different utilization efficiencies in the digestive tract of pigs as a result of feeding different starch sources. Starch sources supplying most of their energy in the form of glucose had higher energy utilization efficiencies, while starch sources supplying most of their energy in the form of volatile fatty acids or lactic acid had lower energy utilization efficiencies.
基金supported by the Hunan Province Key R&D Program Project(2020NK2033)Natural Science Foundation of Hunan Province(2022JJ30317)+1 种基金Innovation Platform and Talent Plan Program of Hunan Province(2022NK4145)National Natural Science Foundation of China(31972600)
文摘This study evaluated the effects of flavonoids from mulberry leaves(FML)on plasma biochemical indices,serum activities of lipid metabolism-related enzymes,fat morphology,fatty acid composition,and lipid metabolism in different adipose tissues of finishing pigs.We used 120 Chinese hybrid barrows of Berkshire and Bama mini-pigs with an average initial body weight of 45.11±4.23 kg.The pigs were randomly assigned to five treatment groups and fed a control diet based on corn,soybean meal,and wheat bran or a control diet supplemented with 0.02%,0.04%,0.08%,or 0.16%FML.Each experimental group had six replicates(pens),with four pigs per pen.After a 7-d adaptation period,the feeding trial was conducted for 58 d.Blood and adipose tissue samples were collected from 30 pigs(one pig per pen)at the end of the test.The results showed that FML supplementation significantly decreased the feed intake to body gain ratio,the plasma concentrations of total cholesterol and free fatty acids,and the serum activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase(linear or quadratic effects,P<0.05),and decreased the plasma triglyceride concentration(quadratic,P=0.07).Increasing FML supplementation increased the average daily gain and serum activities of lipoprotein lipase(linear and quadratic effects,P<0.05)and adipose triglyceride lipase(linear,P<0.05).Dietary FML supplementation decreased the adipocyte area in the dorsal subcutaneous adipose(DSA)tissue of finishing pigs(linear,P=0.05)and increased the adipocyte area in the visceral adipose tissue(quadratic,P<0.01).Increasing FML supplementation decreased the C20:1 content in DSA,abdominal subcutaneous adipose,and visceral adipose tissues of finishing pigs(P<0.05)and increased the C18:3n3 and n-3 PUFA contents(P<0.05).The lipid metabolism genes were regulated by the PPARγ-LXRa-ABCA1 signaling pathway,and their expressions differed in different adipose tissues.These findings suggest that FML improved growth performance,regulated lipid metabolism,inhibited fat production,and improved fatty acid distribution in the adipose tissue of finishing pigs,thereby improving pig fat's nutritional quality and health value.
基金supported by the National Natural Science Foundation of China(32130099)the Scientific and Technological Project of Changsha City(kh2201234)。
文摘Weaning piglets usually suffer from severe diarrhea(commonly known as postweaning diarrhea,PWD)along with intestinal motility disorder.Intestinal peristalsis is mainly regulated by the longitudinal muscle-myenteric plexus(LM-MP).To understand the relationship between intestinal LM-MP function and the development of PWD,we compared the intestinal electrical activity,and the transcriptional profile of the LM-MP between 21-day-old piglets(just weaned,n=7)and 24-day-old piglets(suffered the most severe weaning stress,n=7).The results showed that 24-day-old piglets exhibited different degrees of diarrhea.A significant increase in the slow-wave frequency in the ileum and colon was observed in 24-day-old piglets,while c-kit expression in the intestinal LM-MPs was significantly decreased,indicating that PWD caused by elevated slow-wave frequency may be associated with loss of c-kit.The real-time quantitative PCR(RT-q PCR)and enzyme-linked immunosorbent assay(ELISA)showed that intestinal LM-MPs in 24-day-old piglets may undergo inflammation and oxidative stress.Significant increases in 8-hydroxy-2′-deoxyguanosine and decreases in thioredoxin suggest that weaning may lead to DNA damage in the LM-MP of 24-day-old piglets.In addition,activating transcription factor 3 was significantly upregulated,indicating nerve damage in the LM-MP of 24-day-old piglets.The transcriptomic results showed that most of the differentially expressed genes in the ileal LM-MP after weaning were downregulated and closely related to the cell cycle process.Subsequent RT-q PCR analysis showed that the relative expression of p21 was upregulated,while the expression of cyclin A2,cyclin B1,and proliferating cell nuclear antigen was downregulated in the ileal and colonic LM-MP of 24-day-old piglets,suggesting that weaning may inhibit cell proliferation and cause G1/S cell cycle arrest in ileal and colonic LM-MP.In conclusion,weaning may lead to cell cycle arrest by causing DNA damage in the LM-MP,impairing intestinal motility regulation,and ultimately leading to diarrhea in piglets.
基金the Natural Science Foundation of Hunan Province,China(Grant No.2023JJ30310)Scientific Research Fund of Hunan Provincial Education Department(Grant No.22A0169).
文摘In this study,the discrete element software EDEM was applied to establish a simulation model of non-uniform-sized particle units for Broussonetia papyrifera stalks,which aimed to address the low utilization rate of existing Broussonetia papyrifera harvesting machinery,the significant variation between the simulated model of Broussonetia papyrifera stalks and their actual appearance,as well as the absence of contact parameter calibration.Through a combination of the free-fall collision method,inclined plane sliding method,and inclined plane rolling method,numerical simulation was conducted to analyze the pattern of variations in contact parameters between Broussonetia papyrifera stalks and the steel material of the machinery.Accordingly,these parameters were calibrated.The results showed that the coefficient of restitution between Broussonetia papyrifera stalks and steel materials was 0.321,the static friction factor was 0.589,and the rolling friction factor was 0.078.With the parameters of contact between Broussonetia papyrifera stalks as variables and the experimentally measured pile angle as the objective of optimization,the steepest ascent experiment and the three-factor five-level rotation combination experiment were conducted.In this way,a second-order response model was constructed to analyze the relationship between the contact parameters and the pile angle.Through the optimization analysis of experimental data,it was determined that the coefficient of restitution between Broussonetia papyrifera stalks was 0.21,the static friction factor was 0.24,and the rolling friction factor was 0.03.Furthermore,the calibration results were validated through experimentation to show that the relative error between the obtained pile angle under the context of optimal parameter combination and the actual one was 4.11%.In addition,the relative error of mass flow rate in spiral transport was within a reasonable range,this study lays a foundation both theoretically and statistically for the simulation of contact parameters for Broussonetia papyrifera stalk harvesting processing,mechanical harvesting,and so on.
基金supported by the National Natural Science Foundation of China(32172755,32130099)Hunan Key Research and Development Plan(2022NK2023)Shandong Province Taishan Industry Leading Talents Project Blue Talents Project
文摘This study aimed to determine the regulatory mechanism of dietary zinc lactate(ZL)supplementation on intestinal oxidative stress damage in a paraquat(PQ)-induced piglet model.Twenty-eight piglets(mean body weight 9.51±0.23 kg)weaned at 28 d of age were randomly divided into control,ZL,PQ,and ZL+PQ groups(n=7 in each group).The ZL-supplemented diet had little effect on growth performance under normal physiological conditions.However,under PQ challenge,ZL supplementation significantly improved average daily gain(P<0.05)and reduced the frequency of diarrhea.ZL improved intestinal morphology and ultrastructure by significantly increasing the expression level of the jejunal tight junction protein,zonula occludens-1(ZO-1)(P<0.05),and intestinal zinc transport and absorption in PQ-induced piglets,which reduced intestinal permeability.ZL supplementation also enhanced the expression of antioxidant and antiinflammatory factor-related genes and decreased inflammatory cytokine expression and secretion in PQinduced piglets.Furthermore,ZL treatment significantly inhibited the activation of constitutive androstane receptor(CAR)signaling(P<0.01)in PQ-induced piglets and altered the structure of the gut microbiota,especially by significantly increasing the abundance of beneficial gut microbes,including UCG_002,Ruminococcus,Rikenellaceae_RC9_gut_group,Christensenellaceae_R_7_group,Treponema,unclassified_Christensenellaceae,and unclassified_Erysipelotrichaceae(P<0.05).These data reveal that pre-administration of ZL to piglets can suppress intestinal oxidative stress by improving antioxidant and anti-inflammatory capacity and regulating the crosstalk between CAR signaling and gut microbiota.
基金supported by the National Key R&D Program of China(2022YFD1300504)the National Natural Science Foundation of China(32372827)+1 种基金the science and technology innovation Program of Hunan Prowince(2023RC3201)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2022370).
文摘The objective of this study was to examine the early serum proteomic and inflammatory profiles of weaned piglets subjected to iron deficiency.Twelve healthy piglets(Duroc×Landrace×Large Yorkshire,body weight:4.96±0.05 kg)were weaned at 21 days of age.Subsequently,these animals were randomly allocated to one of two groups,with six replicates in each group(maintaining a male-to-female ratio of 1:1),the control group(administered 100 mg/kg Fe as FeSO_(4)·H_(2)O)and L-Fe group(no additional Fe supplementation).The results showed that 42 days after initiating,compared with control group,routine blood analysis revealed a reduction in serum iron content,red blood cell(RBC)count,hemoglobin(HGB)content,hematocrit(HCT),and mean corpuscular volume(MCV)(P 0.05).During the early stages of iron deficiency,piglets exhibited increased villus height(VH)and the ratio of VH to crypt depth(CD)in the duodenum(P<0.05)and increased expression levels of iron transporters,including duodenal cytochrome(Cybrd),divalent metal transport 1(DMT1),and ferritin light chain(FTL)(P<0.05).Subsequently,isobaric tags for relative and absolute quantitation(iTRAQ)were used to identify serum proteins.Gene Ontology(GO)analysis of the differentially abundant proteins(DAP)revealed that 24 of the 30 DAP were involved in platelet function,immune response,cellular metabolism,transcription,and protein synthesis.Notably,prothrombin,asporin(ASPN),and Rac family small GTPase 3(RAC3)expression was induced,whereas glycoprotein Ib platelet subunit alpha(GPIbA)expression was decreased.This was accompanied by a substantial reduction in serum complement 3(C3)and complement 4(C4)contents(P<0.05),with elevated the contents of interleukin-1β(IL-1β),interleukin-4(IL-4),interleukin-6(IL-6),transforming growth factor-β1(TGF-β1),and tumor necrosis factor-α(TNF-α)(P<0.05).Our findings underscore the essential role of dietary iron supplementation in maintaining iron homeostasis and modulating inflammatory responses in piglets.
基金supported by the National Natural Science Foundation of China (32225047 and U22A20510)Laboratory of Lingnan Modern Agriculture Project (NT2021005)+1 种基金National Center of Technology Innovation for Pigs (NCTIP-XD/B13)double first-class discipline promotion project (2023B10564001)。
文摘Excitatory amino acid transporters(EAATs) are responsible for excitatory amino acid transportation and are associated with auto-immune diseases in the central nervous system and peripheral tissues.However, the subcellular location and function of EAAT2 in macrophages are still obscure. In this study,we demonstrated that LPS stimulation increases expression of EAAT2(coded by Slc1a2) via NF-κB signaling. EAAT2 is necessary for inflammatory macrophage polarization through sustaining mTORC1 activation. Mechanistically, lysosomal EAAT2 mediates lysosomal glutamate and aspartate efflux to maintain V-ATPase activation, which sustains macropinocytosis and mTORC1. We also found that mice with myeloid depletion of Slc1a2 show alleviated inflammatory responses in LPS-induced systemic inflammation and high-fat diet induced obesity. Notably, patients with type Ⅱ diabetes(T2D) have a higher level of expression of lysosomal EAAT2 and activation of mTORC1 in blood macrophages. Taken together, our study links the subcellular location of amino acid transporters with the fate decision of immune cells,which provides potential therapeutic targets for the treatment of inflammatory diseases.
基金supported by the National Natural Science Foundation of China(32372925)the Science and Technology Innovation Program of Hunan Province(2022RC1159)+2 种基金the Changsha Natural Science Funds for Distinguished Young Scholar(kq2009020)the National Key Research and Development Programs of China(2022YFD1300503)the China Agriculture Research System of MOF and MARA(CARS35)。
文摘We previously demonstrated that lipopolysaccharide(LPS)injection-induced immune stress could impair muscle growth in weaned piglets,but the precise mechanisms behind this remain elusive.Here,we found that chronic immune stress induced by LPS resulted in a significant reduction of 36.86%in the total muscle mass of piglets at 5 d post-treatment compared with the control group.At 1 d,prior to muscle mass loss,multiple alterations were noted in response to LPS treatment.These included a reduction in the abundance of Bacteroidetes,an increase in serum concentrations of pro-inflammatory cytokines,compromised mitochondrial morphology,and an upregulation in the expression of dynamin-related protein 1(Drp1),a critical protein involved in mitochondrial fission.We highlight a strong negative correlation between Bacteroidetes abundance and the levels of serum pro-inflammatory cytokines,corroborated by in vivo intervention strategies in the musculature of both pig and mouse models.Mechanistically,the effects of Bacteroidetes on inflammation and muscle mass loss may involve the signaling pathway of the tauro-β-muricholic acid-fibroblast growth factor 15.Furthermore,the induction of overexpression of inflammatory cytokines,achieved without LPS treatment through oral administration of recombinant human IL-6(rh IL-6),led to increased levels of circulating cytokines,subsequently causing a decrease in muscle mass.Notably,pre-treatment with Mdivi-1,an inhibitor of Drp-1,markedly attenuated the LPS-induced elevation in reactive oxygen species levels and rescued the associated decline in muscle mass.Collectively,these data indicate that LPS-induced muscle mass loss was linked to the reduction of Bacteroidetes abundance,increased inflammation,and the disruption of mitochondrial morphology.These insights offer promising avenues for the identification of potential therapeutic targets aimed at mitigating muscle mass loss.
