Intestinal growth and morphology is associated with the increase in heat shock protein 70 expression in weaning piglets through supplementation with glutamine

The objectives of this study were to determine the effects of oral Gln supplementation on growth performance, intestinal morphology, and expression of heat shock protein (Hsp) 70 in weaning piglets. A total of 65 piglets after weaning at 21 d of age (d 0) were used in this experiment. Five piglets were randomly selected and euthanized initially at d 0 to determine baseline values for the expression of Hsp70 in the small intestine. The remaining piglets were randomly assigned to 1 of 2 treatments and received 0 or 1 g of oral Gln/kg of BW every 12 h. After piglets were humanely killed at d 3, 7, and 14 postweaning, the duodenum, jejunum, and ileum of piglets were sampled to evaluate intestinal morphology and the expression and localization of Hsp70. The results indicated that oral Gln supplementation increased plasma concentrations of Gln compared with those in control piglets (P < 0.05). Average daily gain and ADFI were greater in piglets orally supplemented with Gln than in control piglets during the whole period (P < 0.05). The incidence of diarrhea in piglets orally supplemented with Gln was 24% less than (P = 0.064) that in control piglets at 8 to 14 d after weaning. The weights of the jejunum and ileum were greater in piglets orally supplemented with Gln compared with those of control piglets relative to BW on d 14 postweaning (P < 0.05). The villus height and the villus height:crypt depth ratio in the jejunum and the ileum were greater in piglets receiving oral Gln on d 14 postweaning (P < 0.05) than in control piglets. These results indicate that Gln supplementation can influence the intestinal morphology of weaned piglets. The expression of hsp70 mRNA and Hsp70 proteins in the duodenum and jejunum was greater in piglets supplemented with Gln than in control piglets (P < 0.05). However, Gln supplementation had no effect on the expression of hsp70 mRNA and Hsp70 proteins in the ileum. Moreover, the localization of Hsp70 in the cytoplasm indicated that Hsp70 has a cytoprotective role in epithelial cell function and structure. These results indicate that Gln supplementation may be beneficial for intestinal health and development and may thus mitigate diarrhea and improve growth performance. The protective mechanisms of Gln in the intestine may be associated with the increase in Hsp70 expression.     

Dietary protocatechuic acid ameliorates inflammation and up-regulates intestinal tight junction proteins by modulating gut microbiota in LPS-challenged piglets

Background: Weaning is one of the major factors that cause stress and intestinal disease in piglets. Protocatechuic acid(PCA) is an active plant phenolic acid which exists in Chinese herb, Duzhong(Eucommia ulmoides Oliver), and is also considered as the main bioactive metabolite of polyphenol against oxidative stress and inflammation. This study aimed to investigate the effect of PCA on growth performance, intestinal barrier function, and gut microbiota in a weaned piglet model challenged with lipopolysaccharide(LPS).Methods: Thirty-six piglets(Pig Improvement Company line 337 × C48, 28 d of age, 8.87 kg ± 0.11 kg BW) were randomly allocated into 3 treatments and fed with a basal diet(CTL), a diet added 50 mg/kg of aureomycin(AUR), or a diet supplemented with 4000 mg/kg of PCA, respectively. The piglets were challenged with LPS(10 μg/kg BW) on d 14 and d 21 by intraperitoneal injection during the 21-d experiment. Animals(n = 6 from each group) were sacrificed after being anesthetized by sodium pentobarbital at 2 h after the last injection of LPS. The serum was collected for antioxidant indices and inflammatory cytokines analysis, the ileum was harvested for detecting mRNA and protein levels of tight junction proteins by PCR and immunohistochemical staining, and the cecum chyme was collected for intestinal flora analysis using 16 S rRNA gene sequencing.Results: Dietary supplementation of PCA or AUR significantly increased the expression of tight junction proteins including ZO-1 and claudin-1 in intestinal mucosa, and decreased the serum levels of thiobarbituric acid reactive substances(TBARS) and IL-6, as compared with CTL group. In addition, PCA also decreased the serum levels of IL-2 and TNF-α(P < 0.05). Analysis of gut microbiota indicated that PCA increased the Firmicutes/Bacteroidetes ratio(P < 0.05). Spearman's correlation analysis at the genus level revealed that PCA reduced the relative abundance of Prevotella 9, Prevotella 2, Holdemanella, and Ruminococcus torques group(P < 0.05), and increased the relative abundance of Roseburia and Desulfovibrio(P < 0.05), whereas AUR had no significant effect on these bacteria.Conclusions: These results demonstrated that both PCA and AUR had protective effect on oxidative stress, inflammation and intestinal barrier function in piglets challenged with LPS, and PCA potentially exerted the protective function by modulating intestinal flora in a way different from AUR.     

大豆抗原蛋白对断奶仔猪细胞因子及肠上皮紧密连接蛋白Claudin-1 mRNA表达的影响

选取70头24日龄"杜×长×大"断奶仔猪,随机分成7组,每组10头仔猪。对照组(A组)饲喂基础日粮,β-伴大豆球蛋白(β-Conglycinin,7S)(B、C、D组)和大豆球蛋白(Glycinin,11S)试验组(E、F、G组)分别添加500、2 000、5 000μg/kg质量的7S或11S。仔猪断奶时开始饲喂大豆抗原蛋白,分别于24、26、28、30日龄采集血液,测量血清中细胞因子含量。于试验结束时,每组选取5头仔猪放血致死,采集小肠各段,实时荧光定量PCR(qRT-PCR)法检测小肠各段Claudin-1mRNA的相对表达量。结果显示,与对照组相比,随着7S和11S剂量的增加,血清中IL-2、IL-4、IL-6的含量升高,血清中INF-γ的含量降低。与对照组相比,7S与11S试验组中的D、G组各肠段Claudin-1mRNA的相对表达量均显著降低(P0.01),C组的空肠前段、空肠中段和空肠后段均显著降低(P0.01)。与7S试验组相比,除11SB、C组的回肠显著降低,其余各组均显著升高。试验表明,7S和11S均能够通过影响细胞因子的含量,引起断奶仔猪的体液和细胞免疫反应,降低断奶仔猪十二指肠和空肠Claudin-1mRNA相对表达量,引起仔猪肠道黏膜损伤,且7S比11S对仔猪的损伤程度更大。     

Cysteamine improves growth performance and gastric ghrelin expression in preweaning piglets

The aim of the present study was to investigate the effect of cysteamine on growth performance of preweaning piglets and gastric expression of ghrelin mRNA in vivo and in vitro. Twelve litters of newborn piglets were allocated randomly to control and treatment groups. From 15 d of age, piglets in the control group were fed basal creep diet, whereas the treatment group received basal diet supplemented with 120 mg cysteamine per kg of diet until weaning on 35 d of age. Body weight gain, creep feed consumption, and diarrhea rates were recorded, and gastric mucosal tissues were collected for quantifying mRNA expression. To evaluate the direct effect of cysteamine on gastric ghrelin expression, primary cultures of gastric mucosal cells isolated from 35-d-old piglets were exposed to cysteamine for 20 h at 0, 1, 10, and 100 μg/mL, respectively. Dietary cysteamine increased (P < 0.05) average daily creep feed consumption and BW gain in preweaning pigs, which was accompanied by reduction in diarrhea rates. At 35 d of age, piglets treated with cysteamine showed increased (P < 0.05) ghrelin and gastrin and decreased (P < 0.05) somatostatin mRNA expression in gastric mucosa. Moreover, dietary cysteamine treatment increased serum concentration of gastrin (P < 0.05). In vitro, cysteamine significantly increased ghrelin mRNA expression in gastric mucosal cells at the concentration of 10 μg/mL. In conclusion, dietary cysteamine is effective in improving the growth performance and health condition of preweaning piglets, which is associated with its stimulatory effects on gastric ghrelin mRNA expression both in vivo and in vitro.     

Dietary chenodeoxycholic acid improves growth performance and intestinal health by altering serum metabolic profiles and gut bacteria in weaned piglets

Nutritional diarrhea and subsequent performance degradation in weaned piglets are major challenges for the pig industry. Bile acids (BA) can be added to the diet as emulsifiers. This experiment was conducted to investigate the effects of chenodeoxycholic acid (CDCA), a major primary BA, on growth performance, serum metabolic profiles and gut health in weaned piglets. A total of 72 healthy weaned piglets were randomly assigned to the control (CON) and the CDCA groups, which were feed a basal diet and the basal diet supplemented with 200 mg/kg CDCA for 30 d, respectively. Our results demonstrated that CDCA significantly increased final BW and average daily gain (ADG), decreased feed-to-gain (F:G) ratio and tended to reduce diarrhea incidence. In addition, CDCA increased the villus height-to-crypt depth (V:C) ratio, elevated goblet cell numbers and the expression of tight junction proteins, suggesting the enhancement of intestinal barrier function. As an emulsifier, CDCA increased jejunal lipase activity and the mRNA expression of pancreatic lipases. CDCA supplementation also altered the serum metabolic profiles, including increasing the levels of indole 3-acetic acid, N′-formylkynurenine and theobromine that were beneficial for gut health. Moreover, the relative abundance of 2 beneficial gut bacteria, Prevotella9 and PrevotellaceaeTCG-001, were increased, whereas the relative abundance of a harmful bacteria, Dorea, was decreased in the gut of weaned piglets supplemented with CDCA. Importantly, the altered serum metabolic profiles showed a strong correlation with the changed gut bacteria. In conclusion, CDCA improved the growth performance of weaned piglets by improving intestinal morphology and barrier function, and enhancing lipid digestion, accompanied by alterations of serum metabolic profiles, and changes in relative abundance of certain gut bacteria.     

Benzoic acid beneficially affects growth performance of weaned pigs which was associated with changes in gut bacterial populations,morphology indices and growth factor gene expression

This study was conducted to investigate the effects of benzoic acid (BA) on growth performance, intestinal development and intestinal barrier function in weaned pigs. Ninety weaned pigs were randomly assigned to one of three treatments: a basal diet (CON), the basal diet supplemented with 2000 mg/kg benzoic acid (BA1) and 5000 mg/kg benzoic acid (BA2). At the end of days 14 and 42, six pigs per treatment were randomly selected to collect plasma and intestinal samples. Results showed that BA supplementation not only improved final body weight, daily growth and feed conversion ratio from days 15 to 42 and days 1 to 42, but also decreased the activity of plasma diamine oxidase (day 42) and the pH values of jejunal contents (day 14) (p < 0.05). Ileal Bacillus populations (day 14) were increased by BA, while Escherichia coli counts in the ileum and caecum (day 42) were decreased (p < 0.05). Higher Lactobacillus counts occurred in the ileum (day 14, 42) of BA1‐fed piglets as compared to CON and BA2‐fed piglets (p < 0.05). In addition, BA supplementation increased the ratio of villus height to crypt depth (day 14, 42) and decreased the crypt depth (day 14) (p < 0.05). Growth‐stimulating factors (insulin‐like growth factor‐1, day 42; insulin‐like growth factor‐1 receptor, day 14, 42) and tight junction protein (occludin, day 14, 42; zonula occludens‐1, day 42)‐related gene mRNA levels were upregulated in the jejunum of piglets fed BA diets (p < 0.05). In conclusion, this study provides the first evidence that BA has beneficial effects on intestinal development and intestinal barrier function of weaned pigs, which can partly explain why growth performance of pigs was improved by dietary BA supplementation.     

L.fermentum 1.2029对坏死性肠炎肉鸡回肠上皮紧密连接蛋白表达的影响

将240只AA肉鸡随机分为3个处理组:对照组、坏死性肠炎(Necrotic enteritis,NE)模型组及乳酸杆菌处理组。28日龄,每组屠宰24只鸡,对各组肉鸡肠道损伤进行肉眼评分,并采集回肠黏膜样本分别用于电镜下形态观察和Real-time PCR检测紧密连接蛋白claudin-1和occludin的表达。结果显示,乳酸杆菌处理组降低了炎症的损伤程度(P<0.05);电子显微镜观察显示,乳酸杆菌处理组鸡回肠上皮微绒毛较NE模型组有改善;real-time PCR分析显示,乳酸杆菌处理组claudin-1和occludin的表达显著高于NE模型组(P<0.05),但与对照组没有差异。该试验结果表明,L.fermentum1.2029可降低NE的损伤程度,并能有效上调NE条件下claudin-1和occludin的表达,显示其具有保护肠道屏障功能的作用。     

Association of growth rate with hormone levels and myogenic gene expression profile in broilers

Background: The growth rate often varies among individual broilers of the same breed under a common management condition. To investigate whether a variation in the growth rate is associated with a difference in hormone levels and myogenic gene expression profile in broilers, a feeding trial was conducted with 10,000 newly hatched Ross 308 chicks in a commercial production facility under standard management. At 38 d of age,30 fast-, 30 medium-, and 30 slow-growing broilers were selected among 600 healthy male individuals. The levels of insulin-like growth factor-1(IGF-1), triiodothyronine(T3), thyroxine(T4), and growth hormone in the serum or breast muscle were assayed by ELISA or RIA kits, and the expression levels of several representative pro-and anti-myogenic genes in the breast muscle were also measured by real-time PCR.Results: Results showed that both absolute and relative weights of the breast muscle were in linear positive correlations with the body weight of broilers(P 0.001). Fast-growing broilers had higher concentrations of IGF-1 than slow-growing broilers(P 0.05) in both the serum and breast muscle. The serum concentration of T3 was significantly higher in fast-growing birds than in slow-growing birds(P 0.05). However, no difference was observed in growth hormone or T4 concentration among three groups of birds. Additionally, a decreased expression of an anti-myogenic gene(myostatin) and increased expressions of pro-myogenic genes such as myogenic differentiation factor 1, myogenin, muscle regulatory factor 4, myogenic factor 5, IGF-1, and myocyte enhancer factor 2B, C, and D were observed in fast-growing broilers(P 0.05), relative to slow-growing broilers.Conclusions: Collectively, these findings suggested that the growth rate is linked to the hormone and myogenic gene expression levels in broiler chickens. Some of these parameters such as serum concentrations of IGF-1 and T3 could be employed to breed for enhanced growth.     

Sorbic acid improves growth performance and regulates insulin-like growth factor system gene expression in swine

Sorbic acid (SA) is a PUFA with a conjugated double bond. The conjugated fatty acids, including CLA, are multifunctional bioactive fatty acids with the ability to improve growth performance. The effect of SA on pig growth performance was examined to determine its mechanism of action. The ADG, ADFI, and serum IGF-I concentration were examined, as were IGF-I secretion and IGF system gene expression in hepatocytes. Two hundred forty 21-d-old Duroc × Landrace × Yorkshire weaned piglets (6.86 ± 0.02 kg) were randomly divided into 4 groups, each consisting of 3 pens of 20 piglets (10 female and 10 male). The 4 groups of piglets were kept in a temperature-controlled room (26 to 28 °C), and feed and water were provided to the pigs ad libitum. Weanling piglets were fed diets that included 0, 0.5, 2, or 4 g of SA/kg for 42 d. The diet supplemented with 0.5 g/kg of SA improved (P < 0.05) ADG, BW, and G:F, whereas supplementation with all 3 SA doses increased (P < 0.05) ADG and G:F at 21 to 42 d of age. The greatest concentration of plasma triglycerides was observed (P < 0.05) in the 4 g/kg of SA group. The SA increased (0.5 g of SA/kg, P > 0.05; 1 g of SA/kg, P < 0.05; and 2 g of SA/kg, P < 0.05, respectively) plasma total serum protein and globulin concentrations in a dose-dependent manner. It was noted that the smallest SA treatment dose (0.5 g/kg) dramatically increased (P < 0.05) serum IGF-I concentration but decreased (P < 0.05) the concentrations of blood urea N and cortisol. The SA increased (P < 0.05) IGF-I, IGF-II, IGF-I receptor (IGF-IR), and PPARα gene mRNA expression and IGF-I secretion, but not (P > 0.05) IGFBP or PPARγ mRNA expression, in pig primary hepatocytes. These results indicate that SA improves growth performance by regulating IGF system gene expression and hormone secretion.     

L．fermentum1．2029对坏死性肠炎肉鸡回肠上皮紧密连接蛋白表达的影响

将240只AA肉鸡随机分为3个处理组：对照组、坏死性肠炎（Necrotic enteritis,NE）模型组及乳酸杆菌处理组。28日龄,每组屠宰24只鸡,对各组肉鸡肠道损伤进行肉眼评分,并采集回肠黏膜样本分别用于电镜下形态观察和Real—timePCR检测紧密连接蛋白claudin-1和occludin的表达。结果显示,乳酸杆菌处理组降低了炎症的损伤程度（P〈0．05）;电子显微镜观察显示,乳酸杆菌处理组鸡回肠上皮微绒毛较NE模型组有改善;real—timePCR分析显示,乳酸杆菌处理组claudin-1和occludin的表达显著高于NE模型组（P〈0．05）,但与对照组没有差异。该试验结果表明,L．fermentum1．2029可降低NE的损伤程度,并能有效上调NE条件下claudin-1和occludin的表达,显示其具有保护肠道屏障功能的作用。     

纳米氧化锌对断奶仔猪生长性能及腹泻率的影响

本试验通过研究纳米氧化锌(Nano-ZnO)对断奶仔猪生长性能及腹泻率的影响,旨在进一步探寻较低剂量纳米氧化锌替代高锌的可行性.将135头23日龄断奶仔猪按照体重相近、遗传基础相似的原则分为5个处理组,每个处理组3个重复,每个重复9头,用纳米氧化锌和高剂量氧化锌(ZnO)进行饲养对比试验,试验期24 d.其中第1组为处理1组(0 mg/kg),第2,3,4组分别为200,400,600 mg/kg纳米氧化锌组,第5组为高锌组(3000 mg/kg ZnO).结果表明较处理1组(0 mg/kg)而言,无论是纳米氧化锌(200,400,600 mg/kg)还是高锌组(3000 mg/kg ZnO)均可极显著提高日增重(ADG)(P＜0.01);400 mg/kg纳米氧化锌组与高锌组(3000 mg/kg ZnO)在日增重方面差异不显著(P＞0.05).400 mg/kg纳米氧化锌降低腹泻率效果最好,较对照组(0 mg/kg)腹泻率降低49.1%,达到极显著性差异(P＜0.01),较高锌组(3000 mg/kg ZnO)腹泻率降低21.6%,达到极显著性差异(P＜0.01).根据ADG、平均日采食量(ADFI)、料肉比(F/G)、腹泻率等指标综合得出,第3组(400 mg/kg Nano-ZnO)可以达到甚至超过第5组高锌组(3000 mg/kg ZnO)效果.     

Differential expression of inducible nitric oxide synthase is associated with differential Toll-like receptor-4 expression in chicken macrophages from different genetic backgrounds.

The purpose of this study was to examine iNOS gene expression and activity in macrophages from different chicken genetic lines against various bacterial LPS. Furthermore, the possible involvement of surface LPS receptors as candidates for differential iNOS gene induction in these genetic lines of chicken was also examined. Sephadex-elicited abdominal macrophages (1 x 10(6)) as well as iNOS hyper-responder macrophages from a transformed chicken macrophage cell line, MQ-NCSU, were exposed to 5 microg/ml LPS from E. coli, Shigella flexneri, Serratia marcensces, and Salmonella typhimurium. Nitrite levels were quantitated in the culture supernatant fractions of macrophages after 24h by the Griess method. The results showed that macrophages from K-strain (B(15)B(15)) (range from two separate trials: 31-89 microM) and MQ-NCSU (22-81 microM) were high responders whereas macrophages from both GB1 (B(13)B(13)) (15-38 microM) and GB2 (B(6)B(6)) (7-15 microM) chickens were low responders against all LPSs used. Northern blot analysis revealed that K-strain macrophages expressed higher intensity of 4.5Kb iNOS mRNA (iNOS/beta-actin ratio) than macrophages from GB2 regardless of the LPS source. To elucidate possible molecular mechanism(s) involved in iNOS gene expression in these two strains of chickens, the constitutive expression of LPS-related macrophage cell surface receptors, CD14, Toll-like receptor-2 (TLR2), and Toll-like receptor-4 (TLR4), was examined via flow cytometry using anti-human CD14, TLR2 and TLR4 antibodies. CD14 surface expression and intensity was not different between macrophages from K-strain or GB2 chickens. In contrast, while the overall percentage of TLR4-positive macrophages was the same (K-strain, trial 1=92%, trial 2=62%; GB2, trial 1=91%, trial 2=64%), the mean fluorescence intensity (MFI), an indicator of receptor number, was significantly higher (P=0.05) in K-strain macrophages (MFI: trial 1=145; trial 2=131) than GB2 macrophages (MFI: trial 1=101; trial 2=98). Furthermore, TLR2 (a previously thought candidate as LPS signaling molecule) positive cell numbers were higher in K-strain than the GB2 macrophages in one of the two trials with no difference in the intensity of TLR2 expression in either trial. These findings suggest that the observed differences in iNOS expression and activity among the K-strain (hyper-responder) and GB2 (hypo-responder) chickens are, at least in part, due to differential expression of TLR4 (an LPS signaling molecule), leading to more intense LPS-mediated activation of K-macrophages.     

The toll-like receptor-4 (TLR-4) pathway and its possible role in the pathogenesis of Escherichia coli mastitis in dairy cattle

Mastitis is one of the most costly production diseases in the dairy industry that is caused by a wide array of microorganisms. In this review, we focus on the Gram-negative Escherichia coli infections that often occur at periods when the innate immune defence mechanisms are impaired (i.e., parturition through the first 60 days of lactation). There is substantial evidence demonstrating that at these periods, the expected influx of polymorphonuclear neutrophil leukocytes (PMN) into the mammary gland is delayed during inflammation after intramammary infection with E. coli. Here, we provide some hypotheses on the potential mechanisms of action on how the disease may develop under circumstances of immunosuppression, and describe the potential involvement of the toll-like receptor-4 signal transduction pathway in the pathogenesis of E. coli mastitis. In addition, some ideas are proposed to help prevent E. coli mastitis and potentially other diseases caused by Gram-negative infections in general.     

参苓白术散对哺乳仔猪生长性能及肠道菌群的影响

本试验旨在研究基础日粮中添加参苓白术散对哺乳仔猪生长性能及肠道菌群的影响。选用24头新生且胎次相同体质量相近的哺乳仔猪,随机分成4组(每组6头,公母各半),设为对照组、试验Ⅰ组、试验Ⅱ组、试验Ⅲ组。对照组仔猪和母猪整个试验期内均饲喂基础饲粮,试验Ⅰ组母猪从产后0d-哺乳结束基础日粮中添加0.3%的参苓白术散,试验Ⅱ组仔猪从出生后14d-断奶教槽料中添加0.5%的参苓白术散,试验Ⅲ组仔猪断奶前3d教槽料中添加0.5%的参苓白术散,试验时间为35d。结果表明,试验Ⅰ和Ⅱ组仔猪的平均日增重均极显著高于对照组(P<0.01)而料重比极显著低于对照组(P<0.01)。同时,在肠道菌群多样性方面,参苓白术散在属的水平上降低了普氏菌、拟杆菌属、Blautia菌属、普拉菌属、丝杆菌菌属的百分率,提高Succinivibyio、Parabacteroides、Paludibacter菌属的百分率(特别是显著提高了肠道有益菌乳酸杆菌的百分率)。由此可知,在哺乳母猪基础日粮中或断奶前仔猪教槽料中添加参苓白术散能够提高断奶前仔猪生产性能并改变其肠道菌群多样性。     

Eleutheroside B increase tight junction proteins and anti‐inflammatory cytokines expression in intestinal porcine jejunum epithelial cells (IPEC‐J2)

Eleutheroside B (EB) is a phenylpropanoid glycoside with anti‐inflammatory properties, neuroprotective abilities, immunomodulatory effects, antinociceptive effects, and regulation of blood glucose. The aim of this study was to investigate the effects of EB on the barrier function in the intestinal porcine epithelial cells J2 (IPEC‐J2). The IPEC‐J2 cells were inoculated into 96‐well plates at a density of 5 × 10³ cells per well for 100% confluence. The cells were cultured in the presence of EB at concentrations of 0, 0.05, 0.10, and 0.20 mg/ml for 48 hr. Then, 0.10 mg/ml was selected as the suitable concentration for the estimation of transepithelial electric resistance (TEER) value, alkaline phosphatase activity, proinflammatory cytokines mRNA expression, tight junction mRNA and protein expression. The results of this study indicated that the supplementation of EB in IPEC‐J2 cells decreased cellular membrane permeability and mRNA expression of proinflammatory cytokines, including interleukin‐6 (IL‐6), interferon‐γ (INF‐γ), and tumour necrosis factor‐α (TNF‐α). The supplementation of EB in IPEC‐J2 cells increased tight junction protein expression and anti‐inflammatory cytokines, interleukin 10 (IL‐10) and transforming growth factor beta (TGF‐β). In addition, the western blotting and real‐time quantitative polymerase chain reaction (RT‐qPCR) results indicated that EB significantly (p < 0.05) increased the mRNA and protein expression of intestinal tight junction proteins, Claudin‐3, Occludin, and Zonula Occludins protein‐1 (ZO‐1). Therefore, dietary supplementation of EB may increase intestinal barrier function, tight junction protein expression, anti‐inflammatory cytokines, and decrease proinflammatory cytokines synthesis in IPEC‐J2 cells.     

Antioxidant status and expression of inflammatory genes in gut and liver of piglets fed different dietary methionine concentrations

This study investigated the hypothesis that dietary concentrations of methionine (Met), as a precursor of cysteine which is a constituent of glutathione (GSH), affect tissue antioxidant concentrations and the antioxidant defence system in pigs. Forty‐five piglets (DanZucht × Pietrain) were allotted to three groups of similar mean body weight (11.0 ± 0.9 kg). The basal diet was composed of barley, wheat, corn starch, soybean oil, sucrose, cellulose and a mineral supplement with suboptimal concentrations of Met and was supplemented with dl ‐Met to reach 0.16%, 0.20% and 0.24% of dietary Met and 0.40%, 0.44% and 0.48% of dietary Met and cysteine in groups 0.16, 0.20 and 0.24 respectively. After 3 weeks, at slaughter, samples of liver, jejunum mucosa and plasma were collected. Feed intake and weight gains increased and feed:gain ratio decreased when dietary Met concentrations increased. The Trolox equivalent antioxidant capacity (TEAC), concentrations of GSH and thiobarbituric acid reactive substances (TBA‐RS) and the activity of the glutathione peroxidase (GPx) in liver and jejunum mucosa were similar in all groups (p > 0.05). Relative mRNA concentrations of selected target genes of the nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2), the master regulator of the antioxidant response, and of the nuclear factor ‘kappa‐light‐chain‐enhancer’ of activated B‐cells (NF‐κB), the master regulator of inflammation, were largely unaffected both in jejunum and liver. In conclusion, inflammation‐ and oxidative stress‐related pathways on the molecular level, and concentrations of lipid peroxidation products, of antioxidants and of enzymes involved in the antioxidant defence system were mostly unaffected by dietary Met concentration in gut and liver. These findings suggest that suboptimal dietary Met concentrations did not influence the antioxidant defence system of gut and liver in healthy piglets.     

粗纤维浓缩物对断乳仔猪生长性能及腹泻率的影响

选取120头28日龄断乳、体重相近的"杜长大"健康仔猪作为试验动物,根据体重相近、公母各半的原则将其随机分为对照组和试验组,每个组设4个重复,每个重复15头,研究添加日粮中添加粗纤维浓缩物对仔猪生长性能和腹泻率的影响。结果表明,与对照组相比,日粮中添加1%的粗纤维浓缩物,有降低仔猪腹泻率的趋势,但对仔猪的日增重、料重比和日采食量没有明显的影响(P>0.05)。