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1.
Enteric chlamydial infections of pigs with Chlamydia (C.) suis are frequent and often subclinical. The enteric pathogenicity of C. suis strain S45 was investigated in gnotobiotic piglets. Piglets from three litters (n=31) were inoculated with egg-grown chlamydiae at 2-3 days of age (n=17) or used as controls (n=14). They were observed for clinical signs, killed and necropsied sequentially at 2-13 days postinoculation (DPI). Feces were collected daily and investigated with an ELISA for chlamydial antigen. At necropsy, specimens were collected for histopathology and for immunohistochemical, PCR-based, and serological (complement fixation test, ELISA) detection of chlamydiae. Chlamydial replication and associated symptoms and lesions were observed from 2 to 13 DPI and were particularly pronounced within the first week PI. Clinical symptoms consisted of moderate-to-severe diarrhea, slight and transient anorexia, weakness and body weight loss. Immunohistochemistry and ELISA revealed that chlamydial replication was particularly marked at 2-4 DPI and primarily located in the small intestinal villus enterocytes. Further sites of replication included large intestinal enterocytes, the lamina propria and Tunica submucosa, and the mesenteric lymphnodes. Histopathological changes included moderate-to-severe villus atrophy with flattened enterocytes and focal villus tip erosions, and moderate mucosal inflammatory cell infiltrates and lymphangitis in the small intestine. PCR of spleen tissue and blood was mostly negative for chlamydiae, indicating that they did not substantially disseminate into the host up to 13 DPI. All sera were negative for anti-chlamydial antibodies. In conclusion, C. suis strain S45 elicited significant enteric disease and lesions in gnotobiotic piglets indicating its pathogenic potential for swine.  相似文献   

2.
In a series of five 17-d replicate trials, a total of 54 cannulated and 12 noncannulated pigs were used to determine the effects of weaning age (17 d or 24 d) on pH, dry matter percentage, aerobic and anaerobic microflora, lactate, and volatile fatty acid (VFA) concentrations in the jejunum, ileum, and cecum of weanling pigs. At -14 d of age, cannulated pigs were surgically fitted with T-cannulas in the jejunum (n = 20), ileum (n = 18), or cecum (n = 16). Upon weaning, cannulated pigs were individually caged in an environmentally controlled room with ad libitum access to a phase starter diet and water. Noncannulated pigs were killed at weaning and samples were collected from the jejunum, ileum, and cecum. Digesta and fecal swabs from cannulated pigs were collected twice weekly. The pH of cecal contents was lower (P < 0.05) and dry matter percentage was greater (P < 0.05) than those ofjejunal or ileal contents. Pigs weaned at 24 d of age had increased (P < 0.05) E. coli populations 3 d postweaning compared to preweaning populations, regardless of site of collection, whereas this increase was not observed in pigs weaned at 17 d of age. Unweaned pigs maintained higher (P < 0.05) lactobacilli populations compared to weaned pigs; however, populations declined (P < 0.05) in both groups by 3 d postweaning, with pigs weaned at 24 d of age having lactobacilli populations greater than pigs weaned at 17 d of age. Fecal populations of E. coli and lactobacilli declined (P < 0.05), whereas fecal bifidobacteria populations increased (P < 0.05) postweaning, regardless of weaning age. Concentrations of total fecal anaerobes declined (P < 0.05) in pigs weaned at 17 d of age but were maintained in pigs weaned at 24 d of age. Volatile fatty acid concentrations were greater (P < 0.05) in the cecum than in the jejunum or ileum, and acetic acid concentrations decreased (P < 0.05) postweaning regardless of weaning age. A tendency for L+ lactate concentrations to be greater (P < 0.07) in the ileum and jejunum vs the cecum was observed. Results indicate that weaning and weaning age have significant effects on microbial populations and VFA concentrations.  相似文献   

3.
An experimental model for subclinical edema disease was developed in weanling pigs. In multiple experiments, 3-week-old pigs were weaned, then inoculated intragastrically with 10(10) colony-forming units of an SLT-IIv-positive strain of Escherichia coli originally isolated from a pig with edema disease (principals). Control pigs were inoculated with a nonpathogenic E coli strain. Of 39 principals, 8 developed clinical edema disease within 14 days after inoculation. However, 20 of 21 principals that did not develop clinical signs of edema disease, but were submitted for necropsy examination at 14 days after inoculation, had characteristic vascular lesions of edema disease. Vascular lesions, found principally in ileum and brain, consisted of segmental necrosis of myocytes in the tunica media of small arteries and arterioles. None of the pigs inoculated with a nonpathogenic strain of E coli developed edema disease or vascular lesions. None of the principals necropsied at 2 days after inoculation had vascular lesions. Development of vascular lesions by 14 days after inoculation was used as the end point for detecting subclinical edema disease in the model.  相似文献   

4.
51 gnotobiotic and 63 conventional, one-, or two-days-old piglets were divided into five groups and infected orally either with Isospora suis or rotavirus alone, or with both agents simultaneously or successively with alternative sequences and various intervals. 15 gnotobiotic and 10 conventional piglets served as controls. The development of small intestinal lesions after infection with I. suis was biphasic. The dominant alteration resulting from rotavirus infection was villus atrophy, considerably more pronounced and extensive in gnotobiotic than in conventional piglets. Synergistic action of I. suis and rotavirus was manifested both clinically, and morphologically. This action culminated at the time of the actual, or presumed development of merogony of I. suis, i.e. on DPI 3 to 5. The action develops only if the intestinal epithelium is damaged functionally and morphologically by a preceding rotavirus infection. It is concluded that the synergistic action is based on a competition of rotavirus and I. suis for mature, enzymatically active absorptive cells.  相似文献   

5.
The objective of this study was to determine whether a chlamydial strain recovered from growing and finishing swine with conjunctivitis or keratoconjunctivitis could cause the same infections in gnotobiotic pigs. The strain shares biological characteristics with Chlamydia trachomatis. After propagation in Vero cells and preparation of the inoculum (10(7) inclusion-forming units/ml), chlamydial strain H7 was instilled into the ventral conjunctival sac (0.15 ml/sac) of 12 anesthetized 3-day-old gnotobiotic piglets. Four age-matched gnotobiotic piglets were anesthetized and sham infected with uninfected cell culture lysates. None of the principal piglets developed clinical symptoms of conjunctivitis or keratoconjunctivitis. Principal piglets necropsied 7 days postinfection (DPI) had histologic lesions of mild or moderate conjunctivitis; immunohistochemical evaluation revealed chlamydial antigen in conjunctival epithelium. A majority of principal piglets necropsied at 14-28 DPI had histologic lesions of mild conjunctivitis, but chlamydial antigen was not detected by immunohistochemistry. The results indicated that chlamydial strain H7 can cause mild or occasionally moderate conjunctivitis in gnotobiotic pigs, but the conjunctival infection is asymptomatic.  相似文献   

6.
The density of selected enzymes in the goblet cells of the mucous membrane of the small intestine was studied in a group of 12 gnotobiotic piglets experimentally infected with the coccidium Isospora suis one day after parturition (DPP), using the Vickers M-786 scanning and integrating microdensity meter. At an infecting dose of 100,000 oocysts of I. suis, the histochemistry of the goblet cells of the mucous membrane of the piglets changed significantly in the period of 4 to 10 days after infection (DPI). Increases occur in the density of non-specific esterase (EC. 3.1.1.1.) and acid phosphatase (EC. 3.13.2.). The density of acid and neutral muco-substances declines and the densities of alkaline phosphatase (EC. 3.1.3.1.) and aminopeptidase M (EC. 3.4.11.2) are significantly high. The goblet cells of the mid and posterior parts of jejunum are very similar in their histochemistry in the experimentally infected gnotobiotic piglets. In the duodenum and ileum the histochemical picture of the goblet cells shows no substantial difference from the data recorded in the goblet cells of the mucous membrane of the small intestine of the four control piglets at an age of two to seven days.  相似文献   

7.
The pathogenesis of intestinal cryptosporidiosis was studied in 52 conventionally reared and 20 gnotobiotically reared piglets by inoculation with different doses of Cryptosporidium parvum oocysts. The prepatent period of C. parvum in both groups of animals were variable, depending on the number of oocysts administered. The patent period of C. parvum in conventionally reared piglets was 8 or 9 days; in gnotobiotic piglets cryptosporidia were found in feces until Day post infection (DPI) 16, when the last piglet was necropsied. Cryptosporidiosis in conventionally reared piglets is a self-limited diarrheal disease associated with morphological changes within the intestine. The most severe lesion was seen in the posterior jejunum and ileum from DPI 3 to DPI 7, and consisted of villous atrophy, crypt hyperplasia and inflammatory infiltration in the lamina propria. In gnotobiotic piglets cryptosporidia induced severe enterocolitis which occurred at least until DPI 16. The characteristics of enteric lesions were similar to those found in conventionally reared piglets. Intestinal cryptosporidiosis in both groups of animals shifted in the course of infection in the caudal direction and terminated in the large intestine. Examination by scanning electron microscope showed that infected absorptive cells had thicker and longer microvilli than those on non-infected cells; neighboring non-infected cells were hypertrophic, bulbously protuberant with minute microvilli with no distinct intercellular borders. Numerous cryptosporidia in the heterotopic glandular epithelium in the submucosa of cecum and colon on DPI 9 and 10 were found. No differences in the location and degree of cryptosporidial infection between colostrum-fed and colostrum-deprived conventionally reared piglets were found. Sow's colostrum does not appear to protect piglets from C. parvum infection. The role of intestinal microflora in the pathogenesis of cryptosporidiosis in piglets is discussed.  相似文献   

8.
Examinations of fecal specimens from swine of all ages maintained in a totally enclosed confinement facility in south Georgia were conducted in a 5-year survey (1977-1981) to determine the prevalence, intensity, and transmission patterns of intestinal nematode and protozoan parasites. Weaned pigs in the nursery had no detectable parasitic infections except sporadic Isospora suis in newly weaned pigs. Growing-finishing hogs had a low prevalence of Ascaris suum, Oesophagostomum spp. and Balantidium suis. Mean A. suum prevalence and mean eggs per gram feces (EPG) increased until about 200 days of age and then declined. Oesophagostomum spp. and B. suis prevalence and intensity tended to increase throughout life. Gilts (mean age 273 days) in the gestation unit had a higher (P less than 0.01) prevalence of A. suum and lower (P less than 0.01) prevalences of Oesophagostomum spp. and B. suis than sows (mean age 706 days). Similarly, A. suum EPG was higher (P less than 0.01) and Oesophagostomum spp. EPG and B. suis cysts per gram feces (CPG) were lower (P less than 0.01) in gilts than in sows. No evidence for a peri-parturient increase in parasite eggs or cysts was found. Instead, there was a higher prevalence of B. suis (P less than 0.01) in gestating than in lactating animals and more lactating sows than gestating sows were negative for parasites (P less than 0.01). Apparent differences due to location (gestation unit or farrowing unit) were largely attributable to age differences. Trichuris suis infections were rare and not shown to be established in the herd. Strongyloides ransomi in suckling piglets was controlled by anthelmintic therapy. I. suis occurred in piglets throughout the study but was never found in sows in the farrowing unit, either before or after birth of a subsequently infected litter of piglets. No parasites requiring intermediate hosts occurred.  相似文献   

9.
Eighteen 4-day-old gnotobiotic pigs were orally inoculated with porcine enteric calicivirus-like virus (C strain). Seven additional gnotobiotic pigs served as noninoculated controls. Mild diarrhea developed in all inoculated pigs by postinoculation day (PID) 3 and persisted for 3 to 7 days. Severe diarrhea developed in 2 inoculated pigs between PID 4 and 5. Twelve inoculated and 7 control pigs were euthanatized over a 7-day period. Small intestinal mucosal smears were stained with a fluorescein-conjugated anti-porcine enteric calicivirus-like virus serum. Immunofluorescence was observed in villous epithelial cells (primarily in the duodenum or jejunum) of all inoculated pigs, except for 1 pig euthanatized at PID 7. Villus length was determined in histologic sections of the small intestinal specimens from control and inoculated pigs. Statistically significant (P less than 0.01) villus atrophy was found in the duodenum and/or jejunum of inoculated pigs at PID 3 to 7. These observations were confirmed by scanning electron microscopy, which revealed shortening, blunting, fusion, or absence of villi in the duodenum and jejunum of inoculated pigs at PID 3 to 7. Lesions were not seen in control pigs. Calicivirus-like particles were detected by immune electron microscopy in the large intestinal contents and feces of inoculated pigs from PID 1 to 7.  相似文献   

10.
Adenovirus enteritis in pigs   总被引：4，自引：0，他引：4  
Experimental transmissions were done with adenovirus strain 6618 in hysterectomy-produced colostrum-deprived pigs. After an incubation period of 3 to 4 days, all inoculated animals had diarrhea. Histopathologically, many intranuclear inclusion bodies were present on short villi of the terminal parts of jejunum and ileum. With electron microscopy, the inclusion bodies were observed to contain numerous adenovirus particles. Immunoperoxidase-positive cells were seen on short villi of the terminal parts of jejunum and ileum. Adenovirus particles also were detected by negative staining of intestinal contents. In 1 pig (naturally occurring infection), adenovirus enteritis was studied by the aforementioned techniques. Similar intestinal lesions as described in the experimental pigs were observed.  相似文献   

11.
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。  相似文献   

12.
Lectin binding of small intestinal goblet cells was examined in newborn, suckling, and weaned pigs. Sections of duodenum, proximal portion of the jejunum, distal portion of the jejunum, and ileum were embedded in a hydrophilic acrylic resin and treated with each of the following lectins: Canavalia ensiformis, Ricinus communis I, Glycine max, Ulex europaeus I, and Triticum vulgaris. Percentages of goblet cells binding each lectin were calculated within intestinal regions. Differences in lectin-binding affinity were detected among pigs of various ages and among various intestinal regions within pig age groups.  相似文献   

13.
Scanning electron and light microscopy were used in studies of stomach, duodenum, cranial, and caudal portions of the jejunum, ileum, cecum, and spiral colon from 18 gnotobiotic pigs. Five pigs were raised as controls and 13 were exposed at 6 days of age by oral administration of 1.6 X 10(6) colony-forming units of Escherichia coli O138:K81:NM. Infiltration of leukocytes into the mucosa of the stomach seen with the light microscope has not been previously reported. The irregular pattern of the mucosal surface of the stomach formed by the gastric pits and the mucosal extensions on the individual rugae revealed with scanning electron microscopy was different than anticipated. Sections of the ileum from control and infected pigs contained collapsed cells around the extrusion zone at the tips of the villi. These collapsed cells were more numerous in infected pigs and appeared to have sloughed from the area of the extrusion zone resulting in exposure of the lamina propria. Cecum and spinal colon were free of changes. Alterations of the mucosa of the intestinal tract of gnotobiotic pigs infected with E coli as visualized by scanning electron microscopy were considered too inconsistent to be of diagnostic significance.  相似文献   

14.
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.  相似文献   

15.
Sixty‐four pigs from 16 sows were used to evaluate addition of zinc amino acid complex (ZnAA) to lactating sows and gastric nutriment‐intubation of zinc methionine (ZnMet) to suckling pigs on mineral status, intestinal morphology and bacterial translocation after weaning. Sows were fed a barley‐based diet supplying 120 ppm zinc (Zn; control) or the control diet supplemented with 240 ppm Zn from ZnAA. At birth, day‐10 and day‐21 (weaning) of age, pigs from each litter were nutriment‐intubated with 5 ml of an electrolyte solution without or with 40 mg Zn from ZnMet. At weaning, 24 h prior to the collection of small and large intestinal lymph nodes and sections of the duodenum, jejunum and ileum, the pigs received an intramuscular injection of saline without or with 150 μg/kg body weight of Escherichia coli O26:B6 lipopolysaccharide (LPS). With the exception of a tendency (p = 0.09) for lower serum concentration of copper in pigs at weaning from ZnAA‐supplemented sows, there were no differences (p > 0.1) than for pigs from control‐fed sows for mineral status or intestinal morphology. Nutriment‐intubation of ZnMet increased serum (p = 0.001) and liver (p = 0.003) Zn concentrations, number of goblet cells per 250 μm length of jejunal villous epithelium (p = 0.001) and tended (p = 0.06) to enhance jejunum mucosa thickness. Interactive effects (p < 0.05) for higher jejunal villi height and villi:crypt ratio and increased ileal goblet cell counts were apparent for pigs from ZnAA‐supplemented sows that also received nutriment‐intubation of ZnMet. Challenge with LPS increased (p = 0.05) ileal villous width. Nutriment‐intubation of ZnMet decreased (p = 0.05) anaerobic bacteria colony forming unit counts in the large intestinal mesenteric lymph nodes. In conclusion, nutriment‐intubation of ZnMet increased serum and liver tissue concentrations of Zn and resulted in limited improvement to intestinal morphology of weaned pigs.  相似文献   

16.
Eighty 3-week-old crossbred pigs were randomly assigned to six groups (13-14 pigs/group). Group 1 pigs served as uninoculated controls, group 2 pigs were inoculated intranasally (i.n.) with Streptococcus suis serotype 2, group 3 pigs were inoculated i.n. with a modified live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine, group 4 pigs were inoculated i.n. with the same vaccine and with S. suis, group 5 pigs were inoculated i.n. with VR-2385 (a high-virulence strain of PRRSV), and group 6 pigs were inoculated i.n. with VR-2385 and S. suis. Pigs exposed to both PRRSV and S. suis were inoculated with PRRSV 7 days prior to S. suis inoculation. The pigs were 26 days old when inoculated with S. suis. Respiratory disease was significantly more severe in groups 5 and 6. Mortality rate was the highest in group 6 (87.5%). This rate was significantly higher than that observed in all other groups except group 4 (37.5%). The mortality rate in group 2, inoculated with S. suis alone, was 14.3%. No pigs from groups 1, 3, or 5 died prior to the scheduled necropsies at 10 and 28 days postinoculation with PRRSV (DPI). To study the effect of PRRSV and/or S. suis on pulmonary clearance by pulmonary intravascular macrophages, six pigs from each group were intravenously infused with 3% copper phthalocyanine tetrasulfonic acid in saline prior to necropsy at 10 DPI. Mean copper levels in the lungs of pigs in groups 2, 5, and 6 were significantly lower than those in control pigs. The mean percentage of lung tissue grossly affected by pneumonia at 10 DPI was 0%, 1%, 0%, 3%, 64%, and 62% for groups 1-6, respectively. Both gross and microscopic interstitial pneumonia lesions were significantly more severe in the VR2385-inoculated groups (5 and 6). PRRSV was isolated from bronchoalveolar lavage fluid collected at necropsy from 100% of the pigs in groups 5 and 6, 71.4% of pigs in group 4, 38.5% of pigs in group 3, and none of the pigs in groups 1 or 2. Streptococcus suis serotype 2 was cultured from the internal tissues of 7.7%, 28.6%, and 78.6% of the pigs in groups 2, 4, and 6, respectively. Streptococcus suis serotype 2 was isolated from whole blood at necropsy from 7.7%, 35.7%, and 78.6% of pigs in groups 2, 4, and 6, respectively. Significantly more pigs in group 6 had S. suis isolated from whole blood and internal tissues. In summary, both high-virulence PRRSV and S. suis decreased copper clearance, and the incidence of isolation of S. suis and PRRSV was higher in dually inoculated pigs. PRRSV-induced suppression of pulmonary intravascular macrophage function may in part explain PRRSV-associated increased susceptibility to S. suis infection.  相似文献   

17.
In the small intestine mucosa of 24 gnotobiotical piglets experimentally infected the first day post partum with oocysts of the coccidium Isospora suis, the activities of dipeptidylpeptidase IV (EC.3.4.14.5.; DAP IV) and gamma-glutamyl transferase (EC.2.3.2.2.; GGT) in the microvillous zone of enterocytes were evaluated by scanning densitometry. The tissue of the small intestine in piglets infected with a dose of 100,000 oocysts of the coccidia of I. suis was examined in the period from the first till the eleventh day post infection (DPI). In the control piglets at the age of 2-5 days it was found that most of the DAP IV activity was located in the microvillous zone of the enterocytes of the middle jejunum, rear jejunum and ileum. The DAP IV activity of duodenum mucosa was lower; as compared with the activity in the mucosa of the jejunum and ileum it reached 53-57%. In the case of GGT activity, the highest density values of the reaction product were recorded in the microvillous zone of enterocytes of the duodenum and the whole jejunum, the lowest in the ileum mucosa (86-89%) of the activity found in the duodenum and jejunum). During the experimental infection the infected piglets had a significant deficit of both peptidases, especially DAP IV (the whole studied period). The development of GGT activity was slightly different with the onset of the marked decline of the enzyme activity only on the fifth DPI. The lower GGT activity persisted till the eighth DPI. The density of the GGT reaction product began to return to the normal on the ninth to eleventh DPI. No predisposition in the location of the deficit was observed in the peptidases studied during the infection. The decline of the activity of both enzymes influenced also the mucosa of all studied parts of the small intenstine. The difference lay in the relevance of lowering of the density of reaction product of DAP IV and GGT on other DPI and in the different intensities of the return of the activity to the physiological normal.  相似文献   

18.
The redox potential of (Eh) +111 +/- 25 mV was measured in the large intestine of newly born piglets. In the post-weaning period the Eh values decreased significantly to -173 +/- 27 mV and remained at this level also in the healthy sows (-214 +/- 55 mV). The Eh value recorded in dysenteric pigs was -188 +/- 5 mV, and this was not statistically significant in relation to the healthy weaned piglets. The Eh level measured in the blood agar prepared with cysteine and covered by a thick growth of the strain Treponema hyodysenteriae, which had been incubated in an anaerobic medium for five days, was -218 +/- 18 mV. The Eh of piglets after weaning was not the decisive condition for the development of dysentery. However, it can be assumed that the impossibility of eliciting dysentery in microbe-free and gnotobiotic pigs is associated with a relatively high redox potential of a microbially unpopulated or insufficiently populated intestine.  相似文献   

19.
本研究旨在探讨不同剂量中链甘油三酯(MCT)对川藏黑猪断奶仔猪生长性能和肠道微生物菌群比例的影响。试验选择体重为5.4 kg左右、25日龄断奶的川藏黑猪仔猪30头,按体重相近的原则随机分为5组,每组6个重复。对照组饲喂含1.5%豆油的基础日粮,抗生素组在对照组日粮基础上添加50 mg/kg金霉素,试验组分别以0.5%、1.0%和1.5%的MCT等量替代对照组日粮中的豆油,试验期21 d。结果表明:与对照组相比,1.0%MCT组和1.5%MCT组的仔猪末重和平均日增重显著提高(P0.05),耗料增重比和腹泻指数显著降低(P0.05);与抗生素组相比,1.5%MCT组显著提高平均日增重和平均日采食量(P0.05);与对照组相比,随着日粮中MCT添加量的增加,各肠段乳酸杆菌、双歧杆菌占总细菌的比例提高,大肠杆菌比例降低(P0.05);日粮添加MCT显著降低回肠链球菌比例(P0.05),1.0%MCT组显著降低结肠的链球菌比例(P0.05),1.0%MCT组和1.5%MCT组显著降低空肠的链球菌比例(P0.05);与抗生素组相比,日粮添加MCT显著提高各肠段双歧杆菌比例(P0.05),1.5%MCT组显著提高空肠、回肠和盲肠乳酸杆菌比例(P0.05),1.0%MCT组显著降低结肠链球菌比例(P0.05),1.5%MCT组显著降低盲肠和结肠链球菌比例(P0.05)。结果提示,日粮中添加1.5%MCT可提高川藏黑猪断奶仔猪肠道中有益菌的比例并降低有害菌的比例,改善肠道菌群结构,进而降低腹泻指数,提高生长性能。  相似文献   

20.
罗格列酮对断奶仔猪肠黏膜结构和抗氧化能力的影响   总被引：2，自引：0，他引：2  
试验研究罗格列酮(ROS)对脂多糖(LPS)刺激的断奶仔猪肠黏膜结构和抗氧化能力的影响。试验包括3个处理组,对照组注射生理盐水,LPS组注射100μg/kg体重的LPS,ROS组在注射LPS之前的30min注射3mg/kg体重的ROS。注射LPS3h后取样。结果表明:ROS提高了十二指肠和回肠DNA的含量(P0.05);ROS缓解了LPS导致的十二指肠、空肠和回肠隐窝深度的增加(P0.10)和绒毛高度/隐窝深度的降低(P0.01);ROS降低了空肠丙二醛含量(P0.10),提高了十二指肠和空肠SOD活性(P0.05)。结果表明,ROS可能是通过提高肠道抗氧化功能而对LPS刺激的断奶仔猪小肠形态结构的损伤起到一定保护作用。  相似文献   

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