Fatty acids,inflammation and intestinal health in pigs

The intestine is not only critical for nutrient digestion and absorption, but also is the largest immune organ in the body. However, in pig production, inflammation induced by numerous factors, such as pathogen infection and stresses (e.g., weaning), results in intestinal mucosal injury and dysfunction, and consequently results in poor growth of pigs. Dietary fatty acids not only play critical roles in energy homeostasis and cellular membrane composition, but also exert potent effects on intestinal development, immune function, and inflammatory response. Recent studies support potential therapeutic roles for specific fatty acids (short chain and medium chain fatty acids and long chain polyunsaturated fatty acids) in intestinal inflammation of pigs. Results of these new lines of work indicate trophic and cytoprotective effects of fatty acids on intestinal integrity in pigs. In this article, we review the effect of inflammation on intestinal structure and function, and the role of specific fatty acids on intestinal health of pigs, especially under inflammatory conditions.     

日粮膳食纤维与猪肠道健康调控

日粮纤维目前基本认定为第七大营养素,在猪体内中虽然消化率不高,甚至会影响其他营养素消化吸收,但能发酵产生短链脂肪酸,具有改善肠道微生物环境、调控母猪生理行为、调控猪肠道健康等作用。文章综述了日粮纤维在猪体内的营养特性和对肠道的调控作用,为日粮纤维在猪生产中的应用提供参考。     

日粮纤维与猪肠道健康的相关性研究与应用

在生猪产能恢复中,需要特别关注猪只肠道健康问题.很多营养素与猪的肠道健康密切相关,其中日粮纤维就是影响猪只肠道健康的重要营养素之一.日粮纤维在调节猪肠道微生态环境方面表现出异常活跃的营养学功能.日粮中适宜的纤维水平可改善猪肠道微生物种群多样性,调节菌群结构组成,维持猪肠道微生态平衡,提高饲料转化率,具有促进猪只的生长发...     

Intestinal microbiota and its interaction to intestinal health in nursery pigs

The intestinal microbiota has gained increased attention from researchers within the swine industry due to its role in promoting intestinal maturation,immune system modulation,and consequently the enhancement of the health and growth performance of the host.This review aimed to provide updated scientific information on the interaction among intestinal microbiota,dietary components,and intestinal health of pigs.The small intestine is a key site to evaluate the interaction of the microbiota,diet,and host because it is the main site for digestion and absorption of nutrients and plays an important role within the immune system.The diet and its associated components such as feed additives are the main factors affecting the microbial composition and is central in stimulating a beneficial population of microbiota.The microbiotaehost interaction modulates the immune system,and,concurrently,the immune system helps to modulate the microbiota composition.The direct interaction between the microbiota and the host is an indication that the mucosa-associated microbiota can be more effective in evaluating its effect on health parameters.It was demonstrated that the mucosa-associated microbiota should be evaluated when analyzing the interaction among diets,microbiota,and health.In addition,supplementation of feed additives aimed to promote the intestinal health of pigs should consider their roles in the modulation of mucosa-associated microbiota as biomarkers to predict the response of growth performance to dietary interventions.     

肠道的免疫功能及有机酸对肠道健康的影响

正生猪生产的最终目标是将各种饲料转化为猪肉供人类食用。因此,提高饲料的生物转化效率,是提高生猪生产效益和维持生猪生产可持续性的保障。猪采食饲料后在其生物转化过程中,两个初始步骤是饲料消化和营养吸收,主要发生在猪的胃肠道(Gastrointestinal Tract GIT)。除了饲料消化和营养吸收外,猪肠道还包含许多其他生理生化功能,包括中间营养代谢和能量的生成。此外,肠道也是猪机体最     

Biochemical intestinal parameters in pigs reared outdoors and indoors,and in germ-free pigs

Intestinal microbial functions reflect cross-talk between a host and its flora, and external factors may influence these functions. The aim of this investigation was to follow the development of six biochemical microbial-related functions of piglets, raised outdoors (OPs) or indoors (IPs), from birth to slaughter age. The following parameters (microflora-associated characteristic; MAC) were consecutively measured at five different ages: production of short-chain fatty acids (SCFA), conversion of cholesterol to coprostanol and of bilirubin to urobilinogens, inactivation of trypsin, degradation of beta-aspartylglycine and of mucin. Additionally, four parameters (production of SCFA. conversion of cholesterol to coprostanol, inactivation of trypsin, degradation of beta-aspartylglycine) were investigated in faecal samples from germ-free minipigs. The differences in MAC patterns between OPs and IPs were most pronounced at 20 days of age. Differences were found in the total amount of SCFAs, proportions of the acetic, propionic and butyric acids, conversion of bilirubin to urobilinogens, degradation of faecal tryptic activity and degradation of mucin. The values found in the minipigs were within the range of a germ-free animal characteristic (GAC) pattern. Our results show that environmental factors influence the development of some intestinal microbial functions in pigs.     

The role of intestinal volatile fatty acids in the Salmonella shedding of pigs

Factors affecting colonization of the intestinal tract by salmonellas were studied in two pig herds. In herd H 18% of the faecal samples taken from live pigs and 30% of the colon content samples collected at slaughter contained salmonellas. In contrast, the 50 faecal samples taken from pigs of herd L were negative and only 2% of the colon contents collected at the yielded salmonellas. An antibacterial effect inhibiting salmonella multiplication was demonstrable in vitro in colon contents from pigs of herd L. No such effect was found to exist in samples taken from pigs of herd H. The antibacterial effect is due to the non-dissociated volatile fatty acid (VFA) molecules present in the colon content. As the degree of VFA dissociation depends on the pH of the environment, at lower pH values (pH 6.1 +/- 0.2) of the colon contents from herd L the ratio of non-dissociated VFA molecules is higher and the resulting antibacterial effect is stronger than in samples from herd H (pH 7.1 +/- 0.3).     

Chronic intestinal inflammation and intestinal disease in dogs

Normal individuals maintain tolerance to the endogenous bacterial flora residing within their alimentary tract, a phenomenon mediated by the gastrointestinal lymphoid tissue. Loss of this tolerance is a key factor in the development of chronic intestinal inflammation. Manifestations of such uncontrolled inflammation in humans include inflammatory bowel disease and celiac disease. Dogs may similarly be affected, and although the etiopathogenesis is likely similar, the lesions differ. This review includes discussion of the factors involved in breakdown of mucosal tolerance, the immunologic basis of canine enteropathies, and the use of novel immunotherapies for these diseases.     

Dietary supplementation of plant essential oil improves growth performance,intestinal morphology and health in weaned pigs

The present study was conducted to explore the effect of plant essential oil (PEO) on growth performance, intestinal morphology and health in weaned pigs. Twenty-four weaned pigs were assigned into four groups fed with a basal diet (CON) or basal diet containing PEO at a concentration of 50 (PEO50), 100 (PEO100) or 200 ppm (PEO200). After 21 days, pigs were slaughtered and blood and tissue samples were collected. Result showed that PEO200 group significantly increased the average daily gain (ADG) compared with CON group (p < .05). Moreover, PEO supplementation significantly improved the digestibility of DM (p < .05). However, it significantly decreased the serum triglyceride and cholesterol concentration (p < .05). Interestingly, PEO supplementation significantly increased the activity of sucrase in the duodenal and the activity of lactase in the jejunal mucosa (p < .05). Moreover, PEO supplementation improved the growth of intestinal mucosa. As compared to the CON group, the jejunum and ileum villus height were significantly elevated in the PEO200 group (p < .05). Importantly, the expression levels of critical genes associated with nutrient transportation (i.e., GLUT2 and SGLT1) and barrier function (occludin) were significantly elevated in the PEO200 group (p < .05). Moreover, the PEO100 and PEO200 group had higher propionic acid concentration and higher total bacterial gene copies in colon digesta than the CON group (p < .05) respectively. These results not only suggest that PEO has a positive role in the regulation of growth and intestinal health in weaned pigs, but also offer a potential candidate substituting the conventionally used antibiotics in the livestock industry.     

酵母培养物对保育猪的生长性能、肠道健康和免疫应答的影响

216头断奶仔猪用于测定日粮中添加不同含量的酵母培养物(YC)对断奶仔猪的生长性能、养分消化率、肠道形态结构、肠道菌群和免疫应答的影响,并测定YC是否能够替代抗生素生长抑制剂(AGP)。试验1,28日龄断奶仔猪192头(体重为7.5±0.2kg)随机分配到6个处理组:①对照组(没有添加AGP或YC);②AGP组(氯四环素,80mg/kg);③2.5g/kgYC组(益康XP酵母培养物);④5g/kgYC组;⑤10g/kgYC组;⑥20g/kgYC组。每个处理组8个重复栏,每栏4头断奶仔猪,试验期21d。5g/kgYC组的平均日增重(ADG)高于对照组和其他YC组(p<0.05),而所有YC组AGP组之间没有差异。5g/kgYC组、10g/kgYC组和AGP组的平均日采食量(ADFI)高于对照组(p<0.01);而增重/耗料比(G:F)没有受到影响。因此,试验2选用了添加5g/kgYC的日粮。试验2,24头保育猪(21日龄,体重为5.8±0.1kg)随机分成3个处理组试验21d以阐述YC的作用机理。处理组为:①对照组(没有添加AGP或YC);②AGP组;③5g/kgYC组。每周采集血样测定CD4+、CD8+的百分...     

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 4treatments 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) CO...     

Effects of cysteamine supplementation on the intestinal expression of amino acid and peptide transporters and intestinal health in finishing pigs

This study aimed to evaluate the effects of cysteamine supplementation on the expression of jejunal amino acid and peptide transporters and intestinal health in finishing pigs. Sixty barrows were allocated into two experimental diets consisting of a basal control diet supplemented with 0 or 142 mg/kg cysteamine. After 41 days, 10 pigs per treatment were slaughtered. The results showed that cysteamine supplementation increased the apparent digestibility of crude protein (CP) (P < 0.05) and the trypsin activity in jejunal digesta (P < 0.01). Cysteamine supplementation also increased the messenger RNA abundance of SLC7A7, SLC7A9 and SLC15A1, occludin, claudin‐1 and zonula occludens protein‐1 (P < 0.001) in the jejunum mucosa. Increased glutathione content (P < 0.01) and glutathione peroxidase activity (P < 0.05) and decreased malondialdehyde content (P < 0.01) were observed in pigs receiving cysteamine. Additionally, cysteamine supplementation increased the concentrations of secretory immunoglobulin A (IgA) (P < 0.05), IgM (P < 0.001) and IgG (P < 0.001) in the jejunal mucosa. It is concluded that cysteamine supplementation could influence protein digestion and absorption via increasing trypsin activity, enhancing the digestibility of CP, and promoting the expression of jejunal amino acid and peptide transporters. Moreover, cysteamine improved intestinal integrity, antioxidant capacity and immune function in the jejunum, which were beneficial for intestinal health.     

血管紧张素转化酶2(ACE2)在保育猪肠道增生性炎症中的作用

选取49日龄慢性腹泻保育猪为试验对象,测定其血液中葡萄糖(GLU)、白蛋白(ALB)、球蛋白(GLB)、谷草转氨酶(AST)、谷丙转氨酶(ALT)、碱性磷酸酶(ALP)、乳酸脱氢酶(LDH)、甘油三酯(TG)等生化指标;制作病理组织切片,观察胃、十二指肠、空肠、回肠、结肠等组织病理变化;检测保育猪十二指肠、回肠组织中ACE2、Mas受体mRNA的表达及AngⅡ、Ang1-7的含量;比较分析十二指肠、回肠组织中炎症相关因子TNF-α、IL-1β、IL-10 mRNA的表达变化。结果显示,腹泻猪血液中GLB、AST含量显著上调(P0.05),GLU、TG和ALP显著下调(P0.05);病理学观察发现,腹泻猪胃组织上皮损伤脱落;十二指肠肠粘膜脱落、肠腺细胞大量增生、肠隐窝增厚;空肠肠绒毛坏死,黏膜上皮细胞坏死脱落,肠腺上皮细胞增生;回肠、结肠肠腺细胞均明显增生;腹泻组与对照组猪相比,十二指肠中RAS系统相关成员ACE2、Mas受体mRNA表达显著下调(P0.05),Ang1-7含量显著下降(P0.05),但AngⅡ的含量显著升高(P0.05),并且其炎症相关因子TNF-α、IL-1βmRNA表达也显著上调(P0.05,P0.01),IL-10无显著变化。结果表明,腹泻猪表现明显增生性炎症,在此情况下,高水平的AngⅡ的促炎作用处于优势,ACE2及其介导的ACE2-Ang1-7-MAS受体轴的抗炎作用处于劣势。     

Coated fatty acids alter virulence properties of Salmonella Typhimurium and decrease intestinal colonization of pigs

Salmonella Typhimurium infections in pigs are a major source of human foodborne salmonellosis. To reduce the number of infected pigs, acidification of feed or drinking water is a common practice. The aim of the present study was to determine whether some frequently used short- (SCFA) and medium-chain fatty acids (MCFA) are able to alter virulence gene expression and to decrease Salmonella Typhimurium colonization and shedding in pigs using well established and controlled in vitro and in vivo assays. Minimal inhibitory concentrations (MIC) of 4 SCFA (formic acid, acetic acid, propionic acid and butyric acid) and 2 MCFA (caproic and caprylic acid) were determined using 54 porcine Salmonella Typhimurium field strains. MIC values increased at increasing pH-values and were two to eight times lower for MCFA than for SCFA. Expression of virulence gene fimA was significantly lower when bacteria were grown in LB-broth supplemented with sub-MIC concentrations of caproic or caprylic acid (2 mM). Expression of hilA and invasion in porcine intestinal epithelial cells was significantly lower when bacteria were grown in LB-broth containing sub-MIC concentrations of butyric acid or propionic acid (10 mM) and caproic or caprylic acid (2 mM). When given as feed supplement to pigs experimentally infected with Salmonella Typhimurium, coated butyric acid decreased the levels of faecal shedding and intestinal colonization, but had no influence on the colonization of tonsils, spleen and liver. Uncoated fatty acids, however, did not influence fecal shedding, intestinal or tonsillar colonization in pigs. In conclusion, supplementing feed with certain coated fatty acids, such as butyric acid, may help to reduce the Salmonella load in pigs.     

Effect of dietary crude protein level on growth performance,blood characteristics,and indicators of intestinal health in weanling pigs

An experiment was conducted to test the hypothesis that reducing crude protein (CP) in starter diets for pigs reduces post-weaning diarrhea and improves intestinal health. In total, 180 weanling pigs were allotted to 3 diets containing 22, 19, or 16% CP. Fecal scores were visually assessed every other day. Blood samples were collected from 1 pig per pen on days 1, 6, 13, 20, and 27, and 1 pig per pen was euthanized on day 12. Results indicated that reducing dietary CP reduced (P < 0.01) overall average daily gain, gain to feed ratio, final body weight, and fecal scores of pigs. Pigs fed the 16% CP diet had reduced (P < 0.01) serum albumin compared with pigs fed other diets. Blood urea nitrogen, haptoglobin, interleukin-1β, and interleukin-6 concentrations in serum were greatest (P < 0.01) on day 13, whereas tumor necrosis factor-α and interleukin-10 concentrations were greatest (P < 0.01) on day 6. Villus height in the jejunum increased (P < 0.05) and crypt depth in the ileum was reduced (P < 0.01) if the 19% CP diet was fed to pigs compared with the 22% CP diet. A reduction (P < 0.05) in mRNA abundance of interferon-γ, chemokine ligand 10, occludin, trefoil factor-2, trefoil factor-3, and mucin 2 was observed when pigs were fed diets with 16% CP. In conclusion, reducing CP in diets for weanling pigs reduces fecal score and expression of genes associated with inflammation.     

Effects of continuously infusing glucose or casein into the terminal ileum on biomarkers of metabolism,inflammation, and intestinal morphology in growing pigs

Study objectives were to determine the effects of continuously infusing glucose (GLC) or casein (CAS) into the terminal ileum on biomarkers of metabolism, inflammation, and intestinal morphology in growing pigs. Crossbred gilts (n = 19; 81 ± 3 kg body weight [BW]) previously fitted with T-cannulas at terminal ileum were used in the current experiment. Following 4 d of acclimation, pigs were enrolled in 2 experimental 4-d periods (P). During P1, pigs were housed in individual pens and fed ad libitum for collection of baseline parameters. At the beginning of P2, pigs were assigned to 1 of 3 infusion treatments: 1) control (CON; water; 3 liters/d; n = 7), 2) GLC (dextrose 50%; 500 g/d; n = 6;), or 3) CAS (casein sodium salt; 300 g/d; n = 6). Water, GLC, and CAS solutions were continuously infused at a rate of 125 mL/h for the entirety of P2. Animals were euthanized at the end of P2, and intestinal tissue was collected. During P2, average daily feed intake differed across treatments and was reduced in GLC compared with CON pigs (14%), while CAS pigs consumed an intermediate amount (P = 0.05). Average daily gain and final BW were similar across treatments. A treatment by time interaction was observed for blood urea nitrogen (BUN; P < 0.01), as it decreased in GLC (21%) while it gradually increased in CAS (76%) pigs relative to CON pigs. Mild hyperthermia occurred with both GLC and CAS infusions relative to CON (+0.3 and 0.2 °C, respectively; P < 0.01). Blood neutrophils increased in CAS relative to CON pigs (26%) but remained similar between CON and GLC treatments (P < 0.01). Blood monocytes decreased in GLC relative to CON pigs (24%) while CAS pigs had an intermediate value (P = 0.03). Circulating lipopolysaccharide binding protein tended to decrease in GLC (29%) relative to CON pigs but remained similar between CON and CAS pigs (P = 0.10). Plasma tumor necrosis factor-alpha was similar across treatments. Ileum villus height:crypt depth was increased in CAS compared with CON pigs (33%; P = 0.05) while GLC pigs had an intermediate value. Colon myeloperoxidase-stained area increased in CAS compared with CON pigs (45%; P = 0.03) but remained similar between GLC and CON pigs. In summary, continuously infusing GLC or CAS into the terminal ileum appeared to stimulate a mild immune response and differently altered BUN patterns but had little or no effects on blood inflammatory markers, intestinal morphology, or key production parameters.     

Regulation of intestinal health by branched‐chain amino acids

Besides its primary role in the digestion and absorption of nutrients, the intestine also interacts with a complex external milieu, and is the first defense line against noxious pathogens and antigens. Dysfunction of the intestinal barrier is associated with enhanced intestinal permeability and development of various gastrointestinal diseases. The branched‐chain amino acids (BCAAs) are important nutrients, which are the essential substrates for protein biosynthesis. Recently, emerging evidence showed that BCAAs are involved in maintaining intestinal barrier function. It has been reported that dietary supplementation with BCAAs promotes intestinal development, enhances enterocyte proliferation, increases intestinal absorption of amino acids (AA) and glucose, and improves the immune defenses of piglets. The underlying mechanism of these effects is mediated by regulating expression of genes and proteins associate with various signaling pathways. In addition, BCAAs promote the production of beneficial bacteria in the intestine of mice. Compelling evidence supports the notion that BCAAs play important roles in both nutrition and intestinal health. Therefore, as functional amino acids with various physiological effects, BCAAs hold key roles in promoting intestinal development and health in animals and humans.