Effects of Bacillus subtilis on jejunal integrity,redox status,and microbial composition of intrauterine growth restriction suckling piglets

The present study used intrauterine growth restriction (IUGR) piglets as an animal model to determine the effect of Bacillus subtilis on intestinal integrity, antioxidant capacity, and microbiota in the jejunum of suckling piglets. In total, 8 normal birth weight (NBW) newborn piglets (1.62 ± 0.10 kg) and 16 newborn IUGR piglets (0.90 ± 0.08 kg) were selected and assigned to three groups. Piglets were orally gavaged with 10-mL sterile saline (NBW and IUGR groups), and IUGR piglets were orally gavaged with 10-mL/d bacterial fluid (B. subtilis diluted in sterile saline, gavage in the dose of 2 × 10⁹ colony-forming units per kg of body weight; IBS group; n = 8). IUGR induced jejunal barrier dysfunction and redox status imbalance of piglets, and changed the abundances of bacteria in the jejunum. Treatment with B. subtilis increased (P < 0.05) the ratio of villus height to crypt depth (VH/CD) in the jejunum, decreased (P < 0.05) the plasma diamine oxidase (DAO) activity, and enhanced (P < 0.05) the gene expressions of zonula occludens-1 (ZO-1), occludin, and claudin-1 in the jejunum of IUGR piglets. Treatment with B. subtilis decreased (P < 0.05) the concentration of protein carbonyl (PC) and increased (P < 0.05) the activities of catalase (CAT) and total superoxide dismutase (T-SOD) in the jejunum of IUGR piglets. Treatment with B. subtilis also increased (P < 0.05) gene expressions of superoxide dismutase 1 (SOD1), CAT, and nuclear factor erythroid 2-related factor (Nrf2), as well as the protein expressions of heme oxygenase-1 (HO-1), SOD1, and Nrf2 in the jejunum of IUGR piglets. Treatment with B. subtilis also improved the abundances and the community structure of bacteria in the jejunum of IUGR piglets. These results suggested that IUGR damaged the jejunal barrier function and antioxidant capacity of suckling piglets, and altered the abundances of bacteria in the jejunum. Treatment with B. subtilis improved the intestinal integrity and antioxidant capacity while also improved the abundances and structure of bacteria in the jejunum of suckling piglets.     

宫内发育迟缓仔猪小肠形态和屏障功能相关基因的表达特征

为了研究宫内发育迟缓(IUGR)仔猪小肠形态和屏障功能相关基因的表达特征,选取24窝"长白×大白"杂交新生仔猪,每窝选取1头IUGR仔猪和1头正常出生体重(NBW)仔猪,分别于7、21和28日龄屠宰8头IUGR仔猪和8头NBW仔猪,采集小肠样品进行分析.结果表明:1)与NBW仔猪相比,IUGR仔猪7日龄时空肠绒毛高度、...     

Serum biochemical parameters and amino acids metabolism are altered in piglets by early-weaning and proline and putrescine supplementations

The study was to investigate the effect of early-weaning stress and proline (Pro) and putrescine (Put) supplementations on serum biochemical parameters and amino acids (AA) metabolism in suckling and post-weaning pigs. Blood and small intestinal mucosa were harvested from suckling piglets at 1, 7, 14, and 21 d of age and piglets on d 1, 3, 5, and 7 after weaning at 14 d of age, as well as from piglets received oral administration of Pro and Put from 1 to 14 d old. In suckling piglets, the serum glucose, albumin and total cholesterol levels were increased (P < 0.05) with increasing age, whereas the serum globulin, urea nitrogen (BUN), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) levels were lowered (P < 0.05). The concentrations of most serum AA and the AA transporters related gene expressions were highest in 7-d-old piglets (P < 0.05), whereas the phosphorylation status of the mammalian target of the rapamycin (mTOR) signaling pathway in the small intestine increased in piglets from 1 to 21 d old (P < 0.05). Weaning at 14 d old increased (P < 0.05) the BUN and triglycerides levels in serum, as well as jejunal solute carrier family 7 member 6 (SLC7A6), ileal SLC36A1 and SLC1A1 mRNA abundances at d 1 or 3 post-weaning. Weaning also inhibited (P < 0.05) the phosphorylation levels of mTOR and its downstream ribosomal protein S6 kinase 1 (S6K1) and 4E-binding protein-1 (4EBP1) in the small intestine of weanling pigs. Oral administration of Put and Pro decreased (P < 0.05) serum ALP levels and increased (P < 0.05) intestinal SLC36A1 and SLC1A1 mRNA abundances and mTOR pathway phosphorylation levels in post-weaning pigs. Pro but not Put treatment enhanced (P < 0.05) serum Pro, arginine (Arg) and glutamine (Gln) concentrations of weaning-pigs. These findings indicated that early-weaning dramatically altered the biochemical blood metabolites, AA profile and intestinal mTOR pathway activity, and Pro and Put supplementations improved the AA metabolism and transportation as well as activated the intestinal mTOR pathway in weanling-pigs. Our study has an important implication for the broad application of Pro and Put in the weaning transition of piglets.     

Tight junction proteins in the canine epidermis: A pilot study on their distribution in normal and in high IgE-producing canines

Epidermal tight junctions (TJ) have been well-described in human medicine and are involved in many skin diseases such as atopic dermatitis (AD). In dogs, there are no data regarding the implication of TJ in skin diseases including canine AD.The aim of this study was to compare the expression and the distribution of ZO-1, occludin and claudin-1 in the epidermis of healthy and atopic dogs.Skin biopsies from 6 high IgE-producing beagles sensitized to house dust mite (atopic group) were used. Skin specimens from nine healthy dogs without skin issues were sampled (healthy group).Immunoperoxydase staining was used to study the staining pattern of zonula occludens-1 (ZO-1), occludin and claudin-1 in the epidermis of healthy and atopic dogs. Positive controls were healthy human skin samples.Labeling patterns were assessed by 2 examiners blinded to the identities of the specimens. Comparisons between groups were performed using an exact Wilcoxon-Mann-Whitney test.The mean total expression score of claudin-1 was lower in atopic dogs as compared to healthy subjects. Occludin and ZO-1 expression remained unchanged within each group.These results suggest a defect in claudin-1 expression in the nonlesional epidermis of atopic dogs.     

Developmental changes in cholesterol 7alpha- and 27-hydroxylases in the piglet

Hepatic cholesterol 7alpha-hydroxylase (CYP7A) and sterol 27 hydroxylase activities were measured in fetal, newborn, suckling, and weaned piglets from 76 d into gestation to 49 d of age. Hepatic CYP7A activity was not detected in fetal microsomes, but it increased to 6.8 +/- 2.6 pmol/min x mg(-1) protein in suckling piglets at 21 d of age and to 18.2 +/- 2.5 in weaned piglets at 49 d of age. Hepatic CYP7A activity was not different between 49-d-old piglets weaned at 21 d and piglets suckled for 49 d (18.9 +/- 2.6 and 18.2 +/- 2.5 pmol/min x mg protein, respectively). Fasting for 14 h decreased CYP7A activity by 86% in both suckled and weaned piglets. Cholesterol 7alpha-hydroxylase activity remained decreased for at least 5 h after refeeding. Sterol 27-hydroxylase activity was also undetectable near birth, but was detectable by 21 d of age. Postnatally, sterol 27-hydroxylase activity was not influenced by age or suckling and weaning, as was CYP7A. Sterol 27-hydroxylase was decreased by 80% in piglets deprived of feed compared with piglets given free access. In contrast to CYP7A activity, 27-hydroxylase activity returned within 5 h after refeeding to levels observed in piglets given ad libitum access to feed. Similar to CYP7A enzyme activity, hepatic CYP7A mRNA was not detected in newborn piglets, but increased from 2.7 +/- 1.7 pg mRNA/microg RNA in suckling piglets at 21 d to 13.7 +/- 1.2 in 49-d-old piglets weaned at 21 d. As with enzyme activity, feed deprivation decreased CYP7A mRNA to barely detectable levels (< .5 pg/microg RNA), and which remained decreased for at least 5 h following refeeding (.6 +/- .3 and 2.67 +/- .4 pg mRNA/microg RNA for suckled and weaned piglets, respectively). In piglets allowed free access to feed, CYP7A mRNA concentrations were associated positively (P = .001) with enzyme activity. These results suggest that developmental regulation of CYP7A activity is the result of a pretranslational mechanism.     

早期断奶对仔猪空肠和回肠兴奋性氨基酸载体1表达的影响

本试验旨在研究仔猪出生后10~20 d,早期断奶仔猪小肠谷氨酸转运载体基因表达情况与哺乳仔猪的差异。试验分别从40头不同母猪的仔猪中各选出体重相近,10日龄的"杜×长×大"三元杂交仔猪1头,共40头仔猪,随机不配对分为2组,每组20头仔猪,对照组(哺乳组)为哺乳仔猪,随母猪喂养;试验组(断奶组)为断奶仔猪,隔离断奶饲养;试验期10 d。饲养结束,每组随机取12只仔猪,宰杀取空肠和回肠,测定谷氨酸转运载体兴奋性氨基酸转运载体1(EAAC1)蛋白质表达情况和游离氨基酸含量。结果显示,断奶显著降低了仔猪空肠和回肠EAAC1(57和73 ku)及其相关蛋白谷氨酸转运联合蛋白(GTRAP3-18)(50 ku)的蛋白质和mRNA表达量(P0.05)。断奶提高了仔猪空肠游离谷氨酸和总氨基酸含量,却降低了仔猪回肠游离谷氨酸和总氨基酸含量,差异显著(P0.05)。结果提示,早期断奶降低EAAC1和GTRAP3-18的蛋白质含量,这可能与早期断奶仔猪遭受营养谷氨酸缺乏导致的肠道氨基酸吸收转运障碍有关。     

腹水综合征肉鸡空肠黏膜组织结构及相关基因表达分析

试验旨在研究肉鸡腹水综合征发生发展过程中空肠核因子κB （NF-κB）及紧密连接蛋白（闭合蛋白（occludin）、紧密连接蛋白-1（claudin-1）和胞质紧密黏连蛋白1（zonula occluden 1,ZO-1）） mRNA相对表达量,以及绒毛长度、隐窝深度和绒隐比的变化,为肉鸡腹水综合征的防治提供理论依据。选取40羽1日龄罗斯肉鸡常规饲养7 d后,随机分为对照组和模型组（饲料添加3%猪油和4%鱼粉,饮水添加0.12% NaCl,9~11℃低温饲养）,35日龄检测体重,并取心脏组织测腹水心脏指数,取空肠组织以HE染色切片测量绒毛长度和隐窝深度,实时荧光定量PCR检测空肠NF-κB和紧密连接蛋白的基因表达量。结果表明,与对照组相比,模型组肉鸡体重极显著下降（P<0.01）,腹水心脏指数极显著升高（P<0.01）,空肠绒毛长度、绒隐比极显著下降（P<0.01）,隐窝深度极显著升高（P<0.01）,NF-κB mRNA相对表达量极显著升高（P<0.01）,occludin、claudin-1和ZO-1 mRNA相对表达量极显著下降（P<0.01）。表明肠道黏膜结构与功能异常及肠通透性增高促进了肉鸡腹水综合征的发生发展。     

丁酸梭菌对断奶仔猪生长性能、肠道屏障功能和血清细胞因子含量的影响

本试验旨在研究饲粮中添加丁酸梭菌对断奶仔猪生长性能、肠道屏障功能和血清细胞因子含量的影响。试验采用单因子设计,选择28日龄、体重相近、健康状况良好的"杜×长×大"断奶仔猪12头,按完全随机区组设计分为2个组,每组6个重复,单栏饲养。对照组饲喂玉米-豆粕型基础饲粮,试验组饲喂基础饲粮+5×10~5CFU/g丁酸梭菌。试验预试期3 d,正试期14 d。结果表明:与对照组相比,试验组仔猪平均日增重显著提高7.83%(P0.05)、料重比降低5.26%(P0.05);试验组仔猪空肠NOD样受体蛋白(NLRP)3(P0.05)、NLRP6(P0.05)、NLRP12(P0.01)、封闭蛋白1(claudin-1)(P0.01)和紧密连接蛋白2(ZO-2)(P0.05)的mRNA相对表达水平显著或极显著上调,回肠claudin-1和ZO-2的mRNA相对表达水平极显著上调(P0.01);试验组仔猪空肠和回肠中乳酸杆菌数量显著提高(P0.05),空肠中大肠杆菌数量降低2.49%(P0.05),回肠中大肠杆菌数量显著降低(P0.05);试验组仔猪血清白细胞介素(IL)-1β含量降低5.47%、IL-10含量提高25.43%(P0.05)。综上所述,饲粮中添加丁酸梭菌能提高仔猪小肠屏障功能,调节机体免疫和肠道菌群平衡,促进仔猪生长。     

Early life administration of milk fat globule membrane promoted SCFA-producing bacteria colonization,intestinal barriers and growth performance of neonatal piglets

Milk fat globule membrane (MFGM) possesses various nutritional and biological benefits for mammals, whereas its effects on neonatal gut microbiota and barrier integrity remained unclear. This study investigated the effects of MFGM administration on microbial compositions and intestinal barrier functions of neonatal piglets. Sixteen newborn piglets were randomly allocated into a CON group or MFGM group, orally administered with saline or MFGM solution (1 g/kg body weight) respectively during the first postnatal week, and all piglets were breastfed during the whole neonatal period. The present study found that the MFGM oral administration during the first postnatal week increased the plasma immunoglobulin (Ig) G level, body weight and average daily gain of piglets (P < 0.05) on 21 d. Additionally, MFGM administration enriched fecal SCFA-producing bacteria (Ruminococaceae_UCG-002, Ruminococaceae_UCG-010, Ruminococaceae_UCG-004, Ruminococaceae_UCG-014 and [Ruminococcus]_gauvrearuii_group), SCFA concentrations (acetate, propionate and butyrate; P < 0.05) and their receptor (G-protein coupled receptor 41, GPR41). Furthermore, MFGM administration promoted intestinal villus morphology (P < 0.05) and barrier functions by upregulating genes of tight junctions (E-cadherin, claudin-1, occludin and zonula occludin 1 [ZO-1]), mucins (mucin-13 and mucin-20) and interleukin (IL)-22 (P < 0.05). Positive correlation was found between the beneficial microbes and SCFA levels pairwise with the intestinal barrier genes (P < 0.05). In conclusion, orally administrating MFGM during the first postnatal week stimulated SCFA-producing bacteria colonization and SCFA generation, enhanced intestinal barrier functions and consequently improved growth performance of neonatal piglets on 21 d. Our findings will provide new insights about MFGM intervention for microbial colonization and intestinal development of neonates during their early life.     

Effects of housing conditions of farrowing and nursing sows on development of piglets: our own studies and an evaluation of the literature

Results of rearing and growing 3250 piglets derived from 287 litters of 99 German Landrace sows in parities 1-11, from parturition throughout 5 weeks post-weaning, were compared in two farrowing systems. The Group-Farrowing System (GFS) was designed according to natural behaviour of wild pigs and contained 8 farrowing boxes allowing sows and their litters to move freely on an area of 85.2 m2. In contrast, the Single Farrowing System (SFS) was a pen in which sows and their litters were housed individually and could move freely on a restricted area of 6.7 m2. Sows were only fixed during farrowing. The first experiment with a suckling period of 35 days comprised 98 litters from 60 sows (parities 1-4). The second experiment with a suckling period of 28 days involved 189 litters of 70 sows (parities 1-11). In experiment 1, body weight of GFS-piglets was significantly higher by 4.57 kg (19%) at the age of 70 d compared with SFS-piglets. In the second experiment, the proportion of stillborns was significantly lower by 50% in GFS than in SFS. Furthermore, body weight of GFS-piglets showed a greater homogeneity during the first 35 d of life than that of SFS-piglets. In SFS, a positive correlation between parity of the sow and stillborn rate was observed. Behavioural studies in both experiments revealed that GFS-piglets, reared during the suckling period in close contact to other sows and piglets from other litters, were in a better condition at weaning than SFS-piglets. Comparisons with other GFS-types show that the success of farrowing in group-housing is dependent on the type of housing conditions, in particular on the possibility for sows and piglets to live according to their specific behavioural repertoire. The factors critical in this context are discussed.     

3周龄断奶仔猪胰酶发育规律的研究

以 3周龄断奶仔猪为试验材料 ,研究了断奶对仔猪胰酶活性的影响。试验表明 ,3周龄断奶可以显著降低仔猪胰脏中胰淀粉酶、胰蛋白酶、胰糜蛋白酶和胰脂肪酶的活性 ,且在断奶后 2周继续维持断奶时水平。断奶降低了小肠内容物中胰淀粉酶和胰脂肪酶的活性 ,但空肠和回肠胰蛋白酶、胰糜蛋白酶的活性在断奶后并未下降。     

不同形式氧化锌对断奶仔猪生长性能和肠道健康的影响

本试验旨在研究不同形式氧化锌对断奶仔猪生长性能、营养物质表观消化率、血清抗氧化能力及肠道形态的影响。采用完全随机区组试验设计,将144头健康三元(杜×长×大)杂交断奶仔猪[(6.42±0.51) kg]分为3个组,每组6个重复,每个重复8头猪。试验期28 d,分为前期(第1～14天)和后期(第15～28天)2个阶段。各组分别为：普通氧化锌组(在前期基础饲粮中添加1 600 mg/kg普通氧化锌,后期添加110 mg/kg,以锌元素计);钝化氧化锌组(在前期基础饲粮中添加1 600 mg/kg钝化氧化锌,后期添加110 mg/kg,以锌元素计);纳米氧化锌组(在前期基础饲粮中添加1 600 mg/kg纳米氧化锌,后期添加110 mg/kg,以锌元素计)。基础饲粮为玉米-豆粕型。结果表明：1)试验前期,与普通氧化锌组相比,钝化氧化锌组断奶仔猪第14天体重和平均日增重显著提高(P<0.05),料重比显著降低(P<0.05);钝化氧化锌组和纳米氧化锌组腹泻率显著降低(P<0.05)。试验全期(第1～28天),与普通氧化锌组相比,钝化氧化锌组和纳米氧化锌组断奶仔猪腹泻率显著降低...     

Postnatal changes of plasma amino acids in suckling pigs

Amino acids, ammonia, urea, orotate, and nitrate plus nitrite (stable oxidation products of nitric oxide) were determined in plasma of 1- to 21-d-old suckling pigs. Jugular venous blood samples were obtained from pigs at 1, 3, 7, 14, and 21 d of age for analysis of plasma amino acids and metabolites by HPLC and enzymatic methods. Plasma concentrations of arginine and its immediate precursors (citrulline and ornithine) decreased (P < 0.01) progressively (20 to 41%) with increasing age from 3 to 14 d. Plasma concentrations of glutamine declined (P < 0.01) progressively (10 to 31%) during the 1st wk of life. Plasma concentrations of branched-chain amino acids, threonine, and alanine decreased (P < 0.01) (5 to 12%) in 14- and 21-d-old pigs, compared with 1- and 3-d-old pigs. There were no postnatal changes (P > 0.05) in plasma concentrations of other amino acids. Plasma concentrations of ammonia increased (P < 0.01) by 18 and 46%, whereas those of nitrate plus nitrite decreased (P < 0.01) by 16 and 29%, in 7- and 14-d-old pigs, respectively, compared with 1- to 3-d-old pigs. Because arginine plays a crucial role in ammonia detoxification via the hepatic urea cycle and is the physiological substrate for nitric oxide synthesis, our results of the decreased plasma concentrations of arginine and nitrate plus nitrite, as well as the increased plasma ammonia concentration, indicate a hitherto unrecognized deficiency of arginine in 7- to 21-d-old suckling pigs. Arginine is an essential amino acid for piglets and has a great potential to enhance neonatal growth; therefore, further studies are necessary to elucidate the mechanism responsible for arginine deficiency in sow-reared piglets and to identify hormonal and metabolic means for improving neonatal arginine nutrition and growth.     

Glutamine,glutamate,and aspartate differently modulate energy homeostasis of small intestine under normal or low energy status in piglets

Weaning stress may cause reduced energy intake for maintenance of mucosal structure. Gln, Glu, and Asp are major energy sources for the small intestine. This study investigated whether Gln, Glu, and Asp improve the intestinal morphology via regulating the energy metabolism in weaning piglets. A total of198 weaned piglets were assigned to 3 treatments: Control(Basal diet + 1.59% L-Ala); T1(Basal diet + 1%L-Gln + 0.5% L-Glu + 0.1% L-Asp); T2(Low energy diet + 1% L-Gln + 0.5% L-Glu + 0.1% L-Asp). J...     

Effects of Lactobacillus plantarum on the intestinal morphology,intestinal barrier function and microbiota composition of suckling piglets

This study investigated the effect of Lactobacillus plantarum strain 299v on gut health in suckling piglets. Sixty newborn piglets were assigned to control and probiotic treatments, with three litters per treatment (ten piglets/litter). From days 1 to 20 of life, piglets were orally administered a placebo of 0.1% peptone or 1.0 ×  10¹⁰ CFU L. plantarum 299v daily. Six piglets per treatment were sacrificed on day 20, and intestinal tissues (including duodenum, jejunum, ileum and colon) and the intestinal contents from colon segments were collected. The results demonstrated that piglets treated with L. plantarum 299v had a lower diarrhoea incidence than the controls. L. plantarum 299v administration significantly increased the ratio of the villus height to the crypt depth in the jejunum and ileum, as well as the mRNA expression of jejunal occludin and ileal zonula occludens 1 (ZO‐1). The L. plantarum treatment also increased the mRNA abundance of porcine β‐defensin 2 (pBD2) and pBD3 in the jejunum and ileum and of toll‐like receptors (TLRs), such as TLR2, TLR4, TLR6 and TLR9 in the ileum, and significantly upregulated the mRNA abundances of ileal pBD1 and colonic TLR4. Additionally, the L. plantarum 299v treatment significantly changed the structure of the colonic microbiota, as evidenced by the obvious increases in the relative abundances of the phyla Firmicutes and Actinobacteria and of the genus Lactobacillus. Our findings indicate that L. plantarum 299v facilitates the gut health of suckling piglets, probably by improving the intestinal morphology and intestinal barrier function and by modifying the structure of the gut microbiota.     

妊娠后期母猪和仔猪补饲外源精胺对初生和28日龄仔猪肠道形态结构及二糖酶活性的影响

本文通过研究妊娠后期母猪和仔猪补饲外源精胺对初生和28日龄仔猪肠道形态结构和二糖酶活性的影响,初步探讨干预“仔猪早期断奶综合征”的技术措施.试验第1阶段,选择6头体重和膘情相近、胎次为3、已怀孕91 d的健康“长×大”母猪,随机分为Ⅰ、Ⅱ和Ⅲ3个组,每个组设2个重复,每个重复1头母猪.Ⅰ、Ⅱ和Ⅲ组妊娠母猪饲粮中外源精胺的添加量为0、1.5和3.0 mg/kg,饲喂至分娩结束;第2阶段,分娩后母猪采食同一种不含外源精胺的饲粮,Ⅰ、Ⅱ和Ⅲ组哺乳仔猪于7日龄起相应补饲外源精胺添加量为0、3.0和6.0 mg/kg的哺乳仔猪饲粮至28日龄.在仔猪初生和28日龄时,分别从每窝仔猪中选1头接近平均体重的健康仔猪进行屠宰,用于胃肠发育指标的测定.结果表明:与未添加外源精胺相比,妊娠母猪饲粮添加3.0 mg/kg外源精胺显著提高了初生仔猪十二指肠和回肠的柱状细胞数量、十二指肠和空肠的杯状细胞数量(P＜0.05),显著增加了空肠隐窝深度(P＜0.05),显著提高了麦芽糖酶和蔗糖酶比活力(P＜0.05);哺乳仔猪饲粮添加6.0 mg/kg外源精胺显著增加了28日龄仔猪空肠黏膜重(P＜0.05),显著提高了十二指肠和空肠的麦芽糖酶和蔗糖酶比活力(P＜0.05),极显著增加了空肠柱状细胞和杯状细胞数量(P＜0.01),极显著增加了十二指肠和空肠隐窝深度(P＜0.01).因此,在妊娠后期母猪和哺乳仔猪饲粮中添加外源精胺有利于初生和28日龄仔猪肠道形态结构的改善和二糖酶活性的提高.     

外源粪菌干预对受体猪肠道屏障功能的影响研究

为研究外源粪菌干预对受体猪肠道屏障功能的影响,试验选取初生重相近、胎次相同、同日出生的杜×长×大三元杂交哺乳仔猪12窝,随机分为2组,每组6窝(每窝10~12头)。试验组于1~10日龄隔天灌喂1 m L金华猪粪菌悬液进行外源粪菌干预;对照组灌喂等量无菌0.1 mol/L无菌磷酸盐缓冲液(PBS)。试验期间,仔猪自由哺乳采食和饮水,分别于12日龄和27日龄进行屠宰、采样。结果表明:外源粪菌干预可明显减少腹泻,提高受体猪的平均日增重和成活率(P0.05);外源粪菌干预能显著降低27日龄受体猪肠道隐窝深度(P0.05),显著提高肠道绒毛高度/隐窝深度(P0.05);外源粪菌干预能显著增加肠道杯状细胞数和12日龄肠道分泌型免疫球蛋白A阳性(SIgA~+)细胞数(P0.05),同时显著提高肠道黏蛋白Muc2、紧密连接蛋白ZO-1和Occludin表达水平(P0.05),而27日龄试验组的肠道SIgA~+细胞数与对照组无显著差异(P0.05)。综上可知,外源粪菌干预能通过增加肠道杯状细胞和SIgA~+细胞数、提高黏蛋白和紧密连接蛋白表达的方式调节受体猪肠道屏障功能,具有维持猪肠道功能稳态和促进肠道健康的作用。     

敌草快和硫辛酸对育肥猪肠道结构及消化功能的影响

本文旨在研究敌草快和硫辛酸(LA)对育肥猪肠道结构及消化功能的影响,以探究LA对敌草快引起的应激是否有缓解作用。选取24头(70.64±3.61)kg的健康大白阉公猪,按照2×2因子设计,随机分为对照组、LA组、敌草快组和LA+敌草快组,每个组设6个重复,每个重复1头猪。试验期29 d。LA添加剂量为800 mg/kg饲粮,饲喂贯穿试验全程,而一次性腹腔滴注敌草快于试验第15天进行,无腹腔滴注敌草快试验猪滴注等量的生理盐水。于试验第29天对所有试验猪前腔静脉采血后屠宰取样,运用试剂盒检测血浆和肠道氧化损伤标志物的含量以及空肠食糜消化酶的活性,苏木精-伊红(HE)染色后运用图像分析软件观察肠道形态结构并测定绒毛高度、隐窝深度,并计算绒毛高度/隐窝深度(V/C),荧光定量PCR法检测闭合蛋白(occludin)和紧密结合蛋白(ZO-1)的相对表达量。结果表明:1)敌草快极显著升高了试验猪血浆和肠道丙二醛(MDA)、蛋白质羰基(PCO)和8-羟基鸟苷(8-OHd G)的含量(P0.01),极显著降低了十二指肠、空肠及回肠绒毛高度、隐窝深度(P0.01),极显著增大了十二指肠和空肠V/C(P0.01),显著增大了回肠V/C(P0.05),极显著降低了空肠occludin和ZO-1 m RNA相对表达量(P0.01),极显著降低了空肠食糜中淀粉酶、胰蛋白酶以及脂肪酶的活性(P0.01)。2)饲粮中添加LA对试验猪血浆和肠道MDA、PCO和8-OHd G含量的影响均不显著(P0.05),对十二指肠、空肠和回肠的绒毛高度、隐窝深度以及V/C的影响均不显著(P0.05),对空肠occludin和ZO-1 m RNA相对表达量的影响也不显著(P0.05),对空肠食糜中淀粉酶、胰蛋白酶以及脂肪酶活性的影响差异也均不显著(P0.05)。3)在应激状态下,饲粮中添加LA使猪血浆8-OHd G含量显著降低(P0.05),十二指肠绒毛高度、空肠绒毛高度以及回肠隐窝深度显著升高(P0.05),空肠V/C显著降低(P0.05),回肠V/C极显著降低(P0.01),空肠occludin和ZO-1 m RNA相对表达量显著升高(P0.05),空肠食糜淀粉酶和胰蛋白酶的活性显著提升(P0.05)。由此可见,敌草快引起了育肥猪强烈的氧化应激,导致了肠道结构的严重损伤并减弱了肠道的消化功能;在敌草快引起的应激状态下,饲粮中添加800 mg/kg LA能够减缓肠道结构的损伤并能一定程度地提高肠道的消化功能。     

Small intestinal morphology and activity of intestinal peptidases in piglets around weaning

The effect of weaning on small intestinal morphology and the activities of three intestinal peptidases was investigated from 3 days prior to weaning to 9 days post-weaning in 64 piglets. Villous height, crypt depth and mitotic counts were determined at three positions along the small intestine. The activities of aminopeptidase N, dipeptidylpeptidase IV and gamma-glutamyl transpeptidase were measured at five positions along the small intestine. The villous height was maximal on the day of weaning. Post-weaning, the villi shortened at the proximal positions of the small intestine and the minimal length was observed on day 3 after weaning. Villous height did not decrease distally in the small intestine. Increased crypt depth was observed from 3-7 days post-weaning at all positions examined. Mitotic counts showed increased proliferative activity in the crypts from the third day post-weaning. Weaning influenced the activity of aminopeptidase N and dipeptidylpeptidase IV. The activities declined until day 3 post-weaning. After that, the activities increased and they had reached pre-weaning values by day 9 post-weaning. Weaning had only minor effect on the activity of gamma-glutamyl transpeptidase. In summary, weaning induced changes in small intestinal morphology and enzyme activity. The changes were maximal on day 3 post-weaning and during the following days, a gradual recovery of the small intestine was observed.     

The influence of suckling interval on milk production of sows

The objective of this study was to determine whether sow milk yield per gland could be increased by reducing the interval between suckles (suckling interval). Eighteen sows were allocated at their first farrowing to three treatments comprising litter sizes of 6 or 12 piglets or a cross-suckling treatment that was imposed to increase suckling frequency. The cross-suckled treatment comprised two groups of six piglets each. Each suckling group was allowed to suckle the sow during 30-min intervals each day between d 6 and d 28 of lactation. The suckling interval was shorter (P < .05) for cross-suckled sows than for sows suckling single litters of 6 or 12 piglets during early lactation (d 10 to 14) and late lactation (d 24 to 28). Average piglet growth rate between birth and 28 d of age was greatest (P < .05) for piglets in the single litters of six and lowest for piglets in the cross-suckled treatments. Single litters of 12 piglets had the highest (P < .05) litter growth rates, followed by the cross-suckled litters and then the single litters of six piglets. The concentration of lactose and fat in milk from sows remained relatively stable, although milk from the cross-suckled sows contained more protein in early lactation (P < .05). Milk yield of sows was not significantly increased (P > .05) by the cross-suckle treatment, although during early lactation, milk yield tended to be greater from sows in the cross-suckle treatment than from sows suckling single litters of six (8,920 g/d vs 7,819 g/d, P < .1). The concentration of DNA and total RNA and the RNA:DNA ratio in mammary glands was unaffected by treatment (P > .05). Sows with single litters of 12 piglets had the greatest total DNA in their udders (P < .05). However, individual gland weights were heavier (P < .05) in cross-suckled sows than in sows with single litters of 6 or 12 piglets. Increased suckling frequency seemed to play a role in increased mammary gland weight and milk production during lactation.