Porcine neonatal coccidiosis in quebec

Intestinal coccidiosis was diagnosed in 110 diarrheic piglets originating from 66 farrowing operations. These piglets had been submitted alive for necropsy early after the beginning of diarrhea, and the diagnosis of coccidiosis was based on the demonstration of coccidial forms in their jejunum by histopathological examination. Enteropathogenic strains of Escherichia coli were demonstrated in only nine of the 110 piglets while the transmissible gastroenteritis virus and rotavirus were each present in three pigs. The most common lesion was a multifocal villous atrophy in the middle and lower jejunum, and ileum of the affected pigs. Coccidial forms were present in variable numbers of the cells lining the affected villi and they were mainly asexual stages (meronts and merozoites).

In the affected farrowing houses diarrhea began between five and 15 days of age with the highest frequency around seven to ten days of age. Morbidity rates were very variable and mortality was less than 20%. The disease was a persistent problem in large farrowing operations on continuous farrowing programs, and losses were due mainly to retarded growth and treatment costs which were usually inefficient. The disease occurred year round with the highest prevalence in summer and fall months, and in January.

Search for oocysts in fecal samples or colonic contents from 28 of the 110 pigs revealed that 13 of them were shedding oocysts identified as Isospora suis.

     

Passive protection against porcine epidemic diarrhea (PED) virus in piglets by colostrum from immunized cows.

The effects of hyperimmune cow colostrum (HCC) on experimentally induced porcine epidemic diarrhea (PED) were investigated in piglets. In experiment 1, four 2-day-old piglets fed HCC containing an antibody titer of 1:512 and another four piglets fed unimmune cow colostrum (UCC) were orally inoculated with 10LD50 of PED virus. The piglets were given colostrum three times a day at 4 hr intervals. Half of the piglets fed HCC showed diarrhea and recovered, and all piglets survived. In contrast, all piglets fed UCC developed diarrhea and three of them died. In experiment 2, 2-day-old piglets fed HCC containing antibody titers of 1:512, 1:128 and 1:32, and UCC were inoculated with PED virus, and survival rates after challenge were 100, 75, 50 and 0 %, respectively. In experiment 3, 1-day-old piglets fed HCC with 1:512 antibody titer or UCC were inoculated and necropsied at 24, 48 and 72 hr after the inoculation for pathological examination. Piglets fed HCC remained healthy and PED virus antigen was not detected in the epithelial cells of the small intestine, and the length of the villi in small intestine was normal. On the other hand, in piglets fed UCC, villous atrophy and PED virus antigen were observed in epithelial cells of the jejunum and ileum from 24 hr. It was concluded that oral administration of HCC to piglets was effective in preventing PED virus infection and reduced their mortality.     

2种植物提取物复合物对断奶仔猪生长性能以及肠道形态结构、免疫功能和胰岛素样生长因子-Ⅰ含量的影响

本试验旨在研究饲粮中添加2种植物提取物对断奶仔猪生长性能、肠道免疫功能、肠道形态结构和胰岛素样生长因子-Ⅰ(IGF?Ⅰ)含量的影响.选取胎次相近(3～6胎次)、25日龄断奶的"大白×长白"二元仔猪120头,随机分为4组,每组3个重复,每个重复10头.对照组饲喂基础饲粮,抗生素组在基础饲粮中添加100 mg/kg杆菌肽锌...     

Study on Relationship between Intestinal Epithelium Tight Junction Proteins mRNA Expression and Piglets Weaning Diarrhea

The experiment was carried out to compare diarrhea status between Min pig and Landrace pig in a week after weaning, detect two varieties piglets jejunum, ileum and colon tight proteins Zonula occludens-1(ZO-1)and Occludin mRNA expression before and after weaning. The intention was to discuss the relationship between tight proteins expression and piglets weaning diarrhea. The results showed that Min piglets diarrhea rate, diarrhea frequency were very significantly lower than Landrace pig within one week after weaning (P<0.01), diarrhea days was significantly lower than Landrace pig within one week after weaning (P<0.05);Min piglets not weaning group ileum and colon ZO-1 and Occludin mRNA expression was very significantly higher than Landrace pig not weaning group (P<0.01);Min piglets weaning diarrhea group ileum and colon ZO-1 and Occludin mRNA expression was significantly higher than weaning health group (P<0.05). The results indicated that Min piglets intestinal tight junction proteins mRNA high expression before weaning might be had relation with guarantee piglets intestinal health and decrease occurrence diarrhea;Min pig fast recover intestinal mucosa function and rehabilitation by increased tight junction proteins mRNA expression after weaning. So tight junction proteins mRNA high expression before and after weaning had an important significance for piglets to resist weaning diarrhea.     

寡果糖对人源菌群仔猪肠道中IgA和IgG分泌细胞的影响

本文主要研究寡果糖对人源菌群仔猪肠道中IgA和IgG分泌细胞的影响。通过无菌剖腹产获取15头无特定病原菌(specific pathogen free,SPF)仔猪,随机分为三组。第一组为SPF组,经口灌服磷酸钠缓冲液(内含10%甘油)以示对照;第二组为人源菌群(human flora-associated,HFA)组,经口服途径接种人源菌群;第三组为寡果糖(fructo-oligosaccharides,FOS)组,口服途径接种人源菌群且灌喂寡果糖。仔猪饲养于屏障系统内,无菌条件下人工哺育45天。应用免疫组织化学方法进行研究。结果表明:(1)所有仔猪小肠和结肠的固有层中均分布有IgA和IgG分泌细胞。(2)IgA和IgG分泌细胞在十二指肠中分布最多,随着肠段的向后推移IgA和IgG分泌细胞数量有逐渐下降趋势。(3)HFA组和FOS组IgA分泌细胞数量在回肠显著高于SPF组(P<0.01);十二指肠中HFA组IgG分泌细胞数量显著高于SPF组(P<0.01)。(4)FOS组IgA分泌细胞数量在空肠显著高于HFA组外(P<0.05),其他肠段总体上低于HFA组,但差异不显著。本结果提示给新生仔猪接种人源菌群能促进仔猪肠道中IgA和IgG分泌细胞的发育,而寡果糖使肠道IgA和IgG分泌细胞数量呈现下降的趋势。     

Program of vaccination and antibiotic treatment to control polyserositis caused by Haemophilus parasuis under field conditions

The present study investigated the effects of vaccinating sows and piglets or piglets alone against Haemophilus parasuis on the prevalence of H. parasuis in nasal swabs, on the humoral and cellular immune responses, and on the production parameters of piglets at 3 Korean farms with a clinical history of polyserositis caused by H. parasuis. Piglets born to vaccinated or non-vaccinated sows were subdivided into 3 groups: vaccinated sows and vaccinated pigs (VS-VP), non-vaccinated sows and vaccinated pigs (NVS-VP), and non-vaccinated sows and non-vaccinated pigs (NVS-NVP). The proportion of piglets with positive nasal swabs was significantly lower (P < 0.05) in the vaccinated animals (VS-VP and NVS-VP groups) than in the non-vaccinated animals (NVS-NVP group) at 35 and 60 d of age at the 3 farms. The overall growth performance (from 7 to 60 d of age) of the vaccinated piglets was significantly better (P < 0.05) than that of the non-vaccinated piglets at the 3 farms. Piglets in the VS-VP group had significantly higher levels (P < 0.05) of H. parasuis-specific IgG antibodies, lymphocyte proliferation, and interferon-γ-secreting cells than piglets in the NVS-VP and NVS-NVP groups on days 1, 7, 21, 35, and 60 after birth at the 3 farms.     

Porcine group C rotavirus as a cause of neonatal diarrhea in a Quebec swine herd.

A porcine group C rotavirus was found to be the unique cause of a problem of enzootic neonatal diarrhea in a minimal disease herd composed of 190 sows on a continuous farrowing program. During the outbreaks of diarrhea, 10 to 80% of the litters were affected with a morbidity rate of 100% and case fatality rates of 5 to 10%. Clinical signs began 24 to 48 h after birth and were characterized by a profuse yellow diarrhea lasting a few days. Piglets from different outbreaks of diarrhea were necropsied. They had multifocal villous atrophy in the small intestine, especially in the ileum. Group C rotavirus was demonstrated by direct immunofluorescent staining of frozen intestinal sections and by polyacrylamide gel electrophoresis of viral RNA extracted from the intestinal contents of diarrheic piglets. The infection with clinical illness and lesions was reproduced experimentally in newborn piglets by oral inoculation of a suspension prepared from a pool of intestinal contents from diarrheic piglets.     

Experimental Klebsiella and Salmonella infection in neonatal swine.

Twenty colostrum-fed piglets from three sows were separated from the sows 24 hours after birth and were randomly divided into five groups of four piglets each. Every piglet in each of four test groups was orally inoculated with about 10(10) colony forming units of Salmonella typhimurium, Salmonella choleraesuis var Kunzendorf or one of two isolates of Klebsiella pneumoniae. One group served as uninoculated controls. Piglets infected with K. pneumoniae developed severe diarrhea beginning about 12 hours after inoculation. They became dehydrated and weak but continued to drink. There were no morphological alterations in intestinal mucosa when piglets were killed and necropsied 48 or 72 hours after inoculation. Klebseilla pneumoniae was isolated from intestine and feces but not from liver or spleen. Piglets inoculated with S. choleraesuis became lethargic and disinterested in food by 24 hours after inoculation. Diarrhea developed by 48 hours after inoculation. Lesions at necropsy 60 or 72 hours postinoculation were subcutaneous edema, mesenteric lymphadenitis, diffuse intestinal superficial mucosal necrosis with villous atrophy, and focal deep ulceration in the ileum. Salmonella choleraesuis was isolated from all segments of intestine and from feces, liver and spleen. Piglets inoculated with S. typhimurium developed a relatively mild diarrheal disease with lesions similar to those with S. choleraesuis infection but less severe. The inoculated organism was recovered from all areas of intestine and from feces, liver and spleen. Serum from infected and control piglets had high (greater than 1:256) agglutinating titres against S. typhimurium but low titres (0 to 1:8) against S. choleraesuis. The agglutinins were assumed to originate from colostral antibodies.     

Bovine viral diarrhea virus isolated from fetal calf serum enhances pathogenicity of attenuated transmissible gastroenteritis virus in neonatal pigs.

A bovine viral diarrhea virus (BVDV-C) was isolated from swine tissue culture cells used to attenuate the transmissible gastroenteritis virus (TGEV) after 68 passes. Piglets given a pure culture of BVDV-C developed clinical signs similar to those of a mild TGEV infection and recovered by 10 days postexposure. Villous blunting and fusion was observed in the small intestine, and a lymphocyte depletion was observed in Peyer's patches in the ileum. Piglets given a combination of BVDV-C and attenuated TGEV developed clinical signs similar to those of a virulent TGEV infection and were euthanized. The combined infection induced a generalized lymphocyte depletion throughout the lymphatic system and villous atrophy in the intestinal tract. Piglets exposed to a another type I strain of BVDV (NY-1) either alone or in combination with the attenuated TGEV had mild clinical signs similar to those of a TGEV infection. Moderate villous atrophy in the ileum and a lymphocyte depletion in the mesenteric lymph node were observed in these piglets postmortem. The data indicate a potential problem for diagnostic laboratories in relation to a diagnosis of virulent TGEV infections and in the field for young piglets exposed to a BVDV-contaminated TGEV vaccine.     

Intestinal lesions caused by a strain of Chlamydia suis in weanling pigs infected at 21 days of age.

The objective of this study was to determine whether a strain of Chlamydia suis shown previously to be an intestinal pathogen in gnotobiotic piglets could cause diarrhea and intestinal lesions in young weanling pigs. Pigs from 2 sows were randomly assigned to 2 groups. Group 1 included 13 pigs that were weaned at 24 hours of age and then housed in isolator units and fed milk replacer and unmedicated starter ration. Group 2 included 8 pigs that nursed their respective sows, consumed unmedicated starter ration, and were weaned at 21 days of age. Ten pigs in group 1 and 6 pigs in group 2 were inoculated orally with 4 x 108 inclusion-forming units of C. suis strain R27 at 21 days of age. Control pigs were inoculated with sham inoculum. The pigs were necropsied 5-14 days postinoculation (DPI). None of the Chlamydia-infected pigs developed diarrhea. Villus atrophy was seen histologically in sections of ileum from Chlamydia-infected pigs in both groups 5 and 7 days DPI. Lymphangitis and multiple lymphohistiocytic and neutrophilic aggregates were seen in the submucosa, tunica muscularis, and serosa of the distal jejunum, ileum, and colon from Chlamydia-infected pigs in both groups 5-14 DPI. Immunostaining of sections of distal jejunum, ileum, and colon from infected pigs revealed chlamydial antigen in intestinal epithelium and in foci of lymphangitis/inflammation. The results indicated that C. suis strain R27 can cause intestinal lesions in young weanling pigs, and the lesions are similar to those seen in gnotobiotic piglets. The results also indicated that strain R27 causes asymptomatic intestinal infections in young weanling pigs, at least under the conditions of this study.     

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、...     

加味葛根芩连汤对湿热泄泻仔猪肠道炎症和损伤修复的作用

通过用加味葛根芩连汤治疗仔猪的湿热泄泻,探讨其对湿热泄泻仔猪肠道的修复作用。选取8~15日龄未断奶仔猪（大白×长白）30头,其中健康仔猪6头,为对照组;有粪色黄褐而臭、小便短赤、舌质红等症状的泄泻仔猪24头,分为湿热泄泻组、加味葛根芩连汤低剂量组、加味葛根芩连汤中剂量组和加味葛根芩连汤高剂量组,每组6头。对照组和湿热泄泻组仔猪灌服生理盐水,药物组仔猪灌服加味葛根芩连汤（按生药量,低、中、高剂量组药物添加量分别为2.5、5.0和10.0 g·d^-1）,连续5 d。在服药的第0、3、5天记录各组仔猪的粪便评分。取对照组、湿热泄泻组、加味葛根芩连汤中剂量组仔猪十二指肠、空肠、回肠和结肠进行组织切片和H.E.染色,取十二指肠进行增殖性细胞核抗原（PCNA）免疫组化染色;用荧光定量PCR检测对照组、湿热泄泻组、加味葛根芩连汤中剂量组仔猪空肠TLR4、TNF-α、IL-1β和IL-6 mRNA表达量变化。湿热泄泻严重破坏了仔猪的十二指肠、空肠、回肠和结肠结构,尤其是十二指肠和空肠,十二指肠隐窝处PCNA表达量显著升高（P<0.05）。与对照组相比,湿热泄泻组仔猪空肠TLR4（P<0.05）、TNF-α（P<0.01）、IL-1β（P<0.01）和IL-6（P<0.05）mRNA表达量显著升高。相比于湿热泄泻组,加味葛根芩连汤显著降低了仔猪的粪便评分（P<0.05）。中剂量加味葛根芩连汤组仔猪的小肠和结肠的组织结构得到显著改善,十二指肠的肠腔中有不断脱落的绒毛团,绒毛中的PCNA表达量极显著升高（P<0.01）。与湿热泄泻组相比,加味葛根芩连汤中剂量组空肠TLR4（P<0.05）、TNF-α（P<0.01）、IL-1β（P<0.01）和IL-6（P<0.05）mRNA表达量显著降低。综上表明,加味葛根芩连汤可通过促进隐窝干细胞的增殖和降低炎症反应对湿热泄泻造成的仔猪肠道损伤进行修复。     

猪流行性腹泻免疫病理学研究Ⅳ.胃肠道IgA、IgM和IgG产生细胞数及其分泌液和血清中IgA、IgM和IgG含量动态观察

给10头8周龄仔猪经口感染猪流行性腹泻肠管毒,于感染后5、15、25、35和45d各扑杀2头,采取胃及各段肠管标本,用免疫过氧化物酶技术(间接法)检查胃肠粘膜固有层中IgA、IgM和IgG产生细胞数;收集血液及胃、各段肠管分泌液,应用ELISA双抗体夹心法测定IgA、IgM和IgG含量。结果:实验猪感染后第15d,空肠下段、回肠和回盲口处粘膜固有层中IgA和IgM产生细胞明显增多,肠管分泌液中IgA含量与IgA产生细胞数呈正相关,肠道局部免疫反应的高峰比全身性(系统性)免疫出现得早,且周期短。本试验提示,肠道粘膜积极参与了该病的免疫过程;胃肠道对猪流行性腹泻病毒(PEDV)免疫反应的主要部位在空肠下段、回肠和回盲目;参与胃肠道免疫反应的免疫球蛋白产生细胞主要是IgA和IgM产生细胞。     

Scanning electron microscopy of intestine of gnotobiotic piglets infected with porcine rotavirus.

The development of intestinal lesions caused by the porcine rotavirus were studied in six day old gnotobiotic piglets by scanning electron microscopy. The onset of diarrhea followed an incubation period of 17 to 31 hr. The first detectable lesion was observed in the ileum at 12 hr postinfection, a few hours before the onset of diarrhea. At this time enterocytes appeared swollen and began to separate from each other. Seventeen hours after the onset of diarrhea, lesions were quite severe jejunum and ileum. Enterocytes were detaching from the lamina propria leaving denuded areas. Microvilli were sparse on the cell surfaces and there was marked villous atrophy. Regeneration of ileal mucosa was evident at 4.8 days after the onset of diarrhea. Nine days after recovery from diarrhea the intestinal villi had returned to near its normal structure but there remained some evidence of mucosal damage.     

Avirulent K88 (F4)+ Escherichia coli strains constructed to express modified enterotoxins protect young piglets from challenge with a virulent enterotoxigenic Escherichia coli strain that expresses the same adhesion and enterotoxins

Virulence of enterotoxigenic Escherichia coli (ETEC) is associated with fimbrial adhesins and enterotoxins such as heat-labile (LT) and/or heat-stable (ST) enterotoxins. Previous studies using a cell culture model suggest that exclusion of ETEC from attachment to epithelial cells requires expression of both an adhesin such as K88 (F4) fimbriae, and LT. To test the ability of non-pathogenic E. coli constructs to exclude virulent ETEC sufficiently to prevent clinical disease, we utilized a piglet ETEC challenge model. Thirty-nine 5-day-old piglets were inoculated with a placebo (control), or with either of the three K88(+)E. coli strains isogenic with regard to modified LT expression: 8017 (pBR322 plasmid vector control), non-toxigenic mutant 8221 (LT(R192G)) in pBR322, or 8488, with the LT gene fused to the STb gene in pBR322 (LT(R192G)-STb). Piglets were challenged with virulent ETEC Strain 3030-2 (K88(+)/LT/STb) 24h post-inoculation. K88ac receptor-positive piglets in the control group developed diarrhea and became dehydrated 12-24h post-challenge. Piglets inoculated with 8221 or 8488 did not exhibit clinical signs of ETEC disease; most piglets inoculated with 8017 showed diarrhea. Control pigs exhibited significant weight loss, increased blood total protein, and higher numbers of colony-forming units of 3030-2 E. coli in washed ileum and jejunum than treated pigs. This study shows for the first time that pre-inoculation with an avirulent strain expressing adhesive fimbriae and a non-toxic form of LT provides significant short term protection from challenge with a virulent ETEC strain that expresses the same fimbrial adhesion and enterotoxin.     

超微粉中药对保育猪腹泻及肠黏膜免疫细胞的影响

为研制安全、高效环保型保育猪中药添加剂,将72头体重相近的28日龄杜长大断奶仔猪随机分为4组,每组3个重复,每个重复6头猪,分别饲喂基础饲粮、基础饲粮＋抗生素、基础饲粮＋1%中草药组方Ⅰ、基础饲粮＋1%中草药组方Ⅱ,进行为期28 d的饲养试验,统计腹泻频率及腹泻指数、测定肠黏膜免疫细胞。结果显示,中药Ⅱ组效果优于中药Ⅰ组和抗生素组。中药Ⅱ组腹泻持续时间最短、腹泻频率及腹泻指数最低;与对照组相比,对回肠段杯状细胞数量影响最大的是抗生素组,提高14.29%（P〉0.05）。对其它肠黏膜免疫细胞数量影响最大的是中药Ⅱ组,提高十二指肠、空肠及回肠段上皮内淋巴细胞数量分别达23.37%（P〈0.01）、16.33%（P〈0.01）、14.52%（P〈0.01）;提高十二指肠及空肠段杯状细胞数量分别达31.82%（P〈0.01）、26.92%（P〈0.01）;提高十二指肠、空肠及回肠段肥大细胞数量分别达17.99%（P〈0.01）、23.87%（P〈0.01）、18.71%（P〈0.01）。     

幼龄仔猪PEDV感染肠道损伤模型的建立

试验旨在建立猪流行性腹泻病毒（PEDV）感染幼龄仔猪肠道损伤模型。试验选用16头7日龄健康幼龄仔猪（杜×长×大）,随机分为两个处理组：对照组和PEDV组,每个处理8个重复,每个重复1头猪。试验期为10 d,试验期间两个处理组饲喂相同的基础日粮。于试验第7天晚上对PEDV组仔猪口腔灌服PEDV病毒（剂量为10^4.5 TCID₅₀）,对照组灌服等量的生理盐水。于试验第10天早上空腹灌服D-木糖（0.1 g/kg体重）,1 h后前腔静脉采血,屠宰取样,取十二指肠、空肠、回肠等组织样品,测定平均日增重（ADG）、腹泻率（DR）、肠道形态结构、肠道黏膜损伤相关基因mRNA水平。试验结果表明：①PEDV感染显著降低了仔猪ADG（P<0.05）,极显著提高了仔猪腹泻率（P<0.01）;②PEDV感染极显著降低了血浆D-木糖含量、空肠和回肠绒毛高度、十二指肠、空肠和回肠绒毛高度与隐窝深度的比值（P<0.01）,显著提高了十二指肠和空肠隐窝深度（P<0.05）;③PEDV感染极显著提高了仔猪空肠黏膜PEDV M基因的相对表达量（P<0.01）,极显著降低了肠绒毛蛋白（villin）和肠型脂肪酸结合蛋白（i-FABP）基因的相对表达量（P<0.01）。以上结果表明,口腔灌服PEDV可以成功诱导建立幼龄仔猪肠道损伤模型。     

Oral administration recombinant porcine epidermal growth factor enhances the jejunal digestive enzyme genes expression and activity of early-weaned piglets

This study attempted to determine ingested porcine epidermal growth factor (pEGF) on the gastrointestinal tract development of early-weaned piglets. Thirty-two piglets (14-day weaned) were randomly allotted to supplemented with 0 (control), 0.5, 1.0, or 1.5 mg pEGF/kg diet. Each treatment consisted of four replicates with two pigs per pen for a 14 days experimental period. Piglets were sacrificed and gastrointestinal tract samples were collected to measure mucosa morphology, mRNA expression and activities of digestive enzymes in the gastrointestinal tract of piglets at the end of the experiment. Diets supplemented with pEGF failed to influence growth performance but tended to increase jejunal mucosa weight (p < 0.09) and protein content (p < 0.07). Piglets supplemental pEGF induced incrementally the gastric pepsin activity (p < 0.05) and stimulated jejunal alkaline phosphatase (ALP) and lactase activities accompanied with the increase of jejunal ALP and maltase mRNA expression. No effect of pEGF on the activities of all enzymes in ileum except the stimulation of ileal aminopeptide N mRNA expression. These results reveal that dietary pEGF supplementation might enhance gene expression and activities of digestive enzymes in the stomach and jejunum of piglets.     

Effects of dietary supplementation of lipid‐encapsulated zinc oxide on colibacillosis,growth and intestinal morphology in weaned piglets challenged with enterotoxigenic Escherichia coli

This study was aimed to evaluate the effect of dietary supplementation of lipid‐encapsulated (coated) zinc oxide ZnO on post‐weaning diarrhea (colibacillosis) in weaned piglets challenged with enterotoxigenic Escherichia coli (ETEC). Thirty‐two 35‐day‐old weaned piglets were orally challenged with 3 × 10¹⁰ colony forming units of ETEC K88 while eight piglets received no challenge (control). Each eight challenged piglets received a diet containing 100 ppm ZnO (low ZnO), 2500 ppm ZnO (high ZnO) or 100 ppm of lipid (10%)‐coated ZnO (coated ZnO) for 7 days; control pigs received the low ZnO diet. Daily gain, goblet cell density in the villi of the duodenum, jejunum and ileum, and villus height in the jejunum and ileum, which decreased due to the challenge, were equally greater in the coated ZnO and high ZnO groups versus low ZnO group. Fecal consistency score, serum interleukin‐8 concentration, subjective score of fecal E. coli shedding, and digesta pH in the stomach, jejunum and ileum, which increased due to the challenge, were equally low in the coated ZnO and high ZnO groups versus low ZnO. Results suggest that a low level of coated ZnO might well substitute for a pharmacological level of native ZnO in dietary supplementation to alleviate colibacillosis of weaned piglets.     

槲皮素对PEDV感染幼龄仔猪肠道形态、抗氧化功能及空肠脂质代谢基因表达的影响

【目的】 通过研究槲皮素对猪流行性腹泻病毒（PEDV）感染仔猪肠道形态、肠道抗氧化功能及空肠脂质代谢相关基因相对表达量的影响,旨在探讨槲皮素对PEDV感染仔猪肠道的保护作用。【方法】 选取18头健康的7日龄断奶仔猪,随机分为3组：对照组、PEDV组和槲皮素＋PEDV组,每组6个重复,每个重复1头猪。试验期8 d,于试验第0~7天,对槲皮素＋PEDV组仔猪每天口腔灌服10 mg/kg BW的槲皮素,其余组灌服等体积的人工奶。于试验第5天晚上给PEDV组和槲皮素＋PEDV组仔猪口腔灌服10^4.5TCID₅₀的PEDV,对照组仔猪灌服相同体积的PBS溶液。于试验第8天早上屠宰,取仔猪十二指肠、空肠、回肠及结肠组织样品进行检测。【结果】 与对照组相比,PEDV组仔猪空肠和回肠的绒毛高度以及绒毛高度与隐窝深度比值极显著降低（P<0.01）,空肠、回肠和结肠中谷胱甘肽过氧化物酶（GSH-Px）和总超氧化物歧化酶（T-SOD）的活力显著降低（P<0.05）,十二指肠、空肠、回肠和结肠中过氧化氢酶（CAT）的活力显著降低（P<0.05）,回肠和结肠中丙二醛（MDA）的含量显著升高（P<0.05）,空肠中载脂蛋白A1（APOA1）、载脂蛋白B （APOB）、载脂蛋白C2（APOC2）、脂肪酸结合蛋白2（FABP2）、酰基辅酶A合成酶长链家族成员3（ACSL-3）和脂肪酸合酶（FASN）基因的相对表达量极显著下调（P<0.01）。与PEDV组相比,槲皮素＋PEDV组仔猪空肠和回肠的绒毛高度以及绒毛高度与隐窝深度比值极显著提高（P<0.01）,空肠、回肠和结肠中GSH-Px和T-SOD的活力显著提高（P<0.05）,十二指肠、空肠和结肠中CAT的活力显著提高（P<0.05）,回肠和结肠中MDA的含量显著降低（P<0.05）,空肠中APOB、FABP2和FASN基因的相对表达量极显著上调（P<0.01）。【结论】 添加槲皮素可有效缓解PEDV感染导致的仔猪肠道损伤,提高仔猪肠道抗氧化能力以及空肠脂质代谢的能力。