共查询到20条相似文献，搜索用时 31 毫秒
1.
Species-specific DNA probes for Campylobacter species isolated from pigs with proliferative enteritis 总被引：3，自引：0，他引：3
Cloned, chromosomal DNA probes from porcine isolates of Campylobacter hyointestinalis and C. mucosalis were developed for the detection and identification of these putative swine enteric pathogens. High molecular weight chromosomal DNA from each species was used to construct genomic libraries in plasmids. Recombinants were selected which hybridized strongly to the homologous organism, but not to any other species of Campylobacter. Species-specific recombinants were labeled with phosphorus-32 and tested for sensitivity by dot blot hybridization to various dilutions of DNA and bacteria from each swine species, including C. hyointestinalis, C. mucosalis, C. coli and C. jejuni. Specificity was tested by hybridizing these probes against various strains of C. hyointestinalis or C. mucosalis, and against reference strains of all other described Campylobacter species. A C. hyointestinalis-specific probe and a C. mucosalis-specific probe were identified which were capable of detecting 1 ng of DNA or 10(4) cfu by bacterial spot blotting on nylon membranes. These probes hybridized to intestinal mucosal scrapings containing C. hyointestinalis and C. mucosalis obtained from pigs with proliferative enteritis, but not to material from normal pigs. Thus, cloned, chromosomal DNA probes may be useful in the detection and identification of bacteria involved in swine proliferative enteritis. 相似文献
2.
Campylobacter sputorum subsp mucosalis and Campylobacter hyointestinalis infections in the intestine of gnotobiotic pigs 总被引：6，自引：0，他引：6
T R Boosinger H L Thacker C H Armstrong 《American journal of veterinary research》1985,46(10):2152-2156
At 4 days of age, 7 gnotobiotic pigs were orally inoculated with broth cultures of both Campylobacter sputorum subsp mucosalis (CSM) and Campylobacter hyointestinalis (CH). One pig was killed and evaluated each week for 7 weeks. Forty-eight hours after inoculation, CH and CSM were recovered from the feces of the pigs; thereafter, only CH was recovered. Organisms morphologically typical of Campylobacter sp were observed on the mucosal surface and on the crypt epithelial cells of the ileum, cecum, and colon from post-inoculation weeks (PIW) 2 through 7. Bacteria were clustered around the surface opening of goblet cells in pigs at PIW 6 and 7. Crypt epithelial cell proliferation and intracellular bacteria were not seen, except in 1 pig (killed at PIW 7) in which intracellular bacteria were seen only in the cecum. Therefore, CSM and CH did not induce porcine proliferative enteritis in gnotobiotic pigs. 相似文献
3.
Intestinal tissues from swine affected with proliferative enteritis were ground, filtered through a 0.65-micron pore membrane filter, diluted, and injected into 7-day-old embryonated hens' eggs via the yolk sac. At 2, 4, and 7 days later, yolk sac swab specimens taken from live embryos were cultured for Campylobacter species. Campylobacter hyointestinalis was recovered from eggs injected with tissues of swine with acute hemorrhagic proliferative enteritis at dilutions up to 10(-4). Campylobacter mucosalis was recovered from eggs injected with tissues of swine with chronic proliferative enteritis at dilutions up to 10(-6). Campylobacter coli was recovered from several specimens without lesions of proliferative enteritis and also from some specimens with lesions of proliferative enteritis. Two previously undescribed hemolytic Campylobacter species designed as hemolytic number 1 and hemolytic number 2 were recovered from normal and experimentally inoculated swine tissues. Few contaminating organisms grow in eggs and these were usually recovered at dilutions of 10(-2) or less. Recovery of Campylobacter species by use of these techniques was seldom successful in tissues stored at -70 C for more than 6 months. 相似文献
4.
Reproduction of proliferative enteritis in gnotobiotic pigs 总被引：3，自引：0，他引：3
Gnotobiotic pigs dosed orally with filtrates (0.8 and 0.65 micron) of intestinal mucosa from a pig affected by proliferative haemorrhagic enteropathy developed lesions of proliferative enteritis, affecting mainly the ilea. Other piglets dosed with filtrates of affected mucosa from the same source and from other proliferative haemorrhagic enteropathy or intestinal adenomatosis mucosae, did not develop lesions. All inocula contained numerous campylobacter-like organisms evident in stained smears, Campylobacter coli and C mucosalis. C coli colonised the intestines of all the pigs, C hyointestinalis (which was not detected in the inocula) did so in some affected and unaffected pigs while C mucosalis was not recovered from any of the intestines. Although other explanations are possible the number and viability of the intracellular campylobacter-like forms is likely to be the critical factor in infectivity. In affected intestines the crypts were colonised by campylobacter-like organisms, and their attachment and entry into enterocytes was associated with cellular proliferation. Immunofluorescence reactions suggested that the intracellular campylobacter-like organisms were antigenically distinct from the known Campylobacter species. It is possible, therefore, that porcine proliferative enteritis is caused by a further unidentified Campylobacter species, or that there is a marked antigenic change of C hyointestinalis or C coli on entry into porcine enterocytes. 相似文献
5.
Three- to six-week-old hamsters were orally inoculated with broths containing one of the following cultures: Campylobacter mucosalis; C. hyointestinalis; C. coli; C. jejuni, all of porcine proliferative enteritis origin, or else C. jejuni of hamster origin. Hamsters given the last of those organisms were shown to have colonisation of their intestines by C. jejuni and 36 of 40 developed an acute enteritis. Mild hyperplasia of enterocytes in ileal crypts was evident in one hamster 2 days after it was given C. coli. No other lesions were detected. Further 3-week-old hamsters were orally inoculated with homogenised intestinal mucosa collected from 4 pigs (A-D) affected by proliferative enteritis. Lesions of proliferative enteritis were detected in 7 of 41 hamsters necropsied 10-21 days after being dosed with mucosas B or D. Marked hyperplasia of ileal enterocytes, associated with numerous intracellular Campylobacter-like organisms, were invariably detected in experimentally affected hamsters. No particular Campylobacter sp. was consistently isolated. None of the controls had demonstrable lesions. The results suggested that cross-species transmission of proliferative enteritis was possible from pigs to hamsters. Therefore a common initiating or aetiological agent may be present. No specific organism was identified as filling this role by inoculation of hamsters with pure cultures. 相似文献
6.
Plasmid profiles of six species of Campylobacter from human beings, swine, and sheep 总被引：2，自引：0，他引：2
T R Boosinger W T Blevins J V Heron J L Sunter 《American journal of veterinary research》1990,51(5):718-722
Twenty-four isolates representing 6 species of Campylobacter were screened for plasmids. A large plasmid with an approximate molecular weight of 38 Mdal was detected in 5 C jejuni isolates originally recovered from diarrheic human beings, in one isolate of C coli recovered from diarrheic pigs, and in 1 isolate of C sputorum ssp mucosalis and 2 isolates of C hyointestinalis recovered from pigs with proliferative enteritis. One isolate of C coli and 1 isolate of C hyointestinalis contained an additional smaller plasmid with an approximate molecular weight of 1.6 Mdal; this plasmid was partially mapped by restriction endonuclease digestion. Fifteen Campylobacter isolates contained no detectable plasmids: 2 C coli, 2 C sputorum ssp mucosalis, 2 C fecalis, 1 C fetus ssp fetus, and 8 C hyointestinalis isolates. In summary, 37.5% of the Campylobacter isolates contained a 38-Mdal plasmid, with 8% having both 38 Mdal and 1.6-Mdal plasmids; 62.5% contained no detectable plasmids. 相似文献
7.
Experimentally induced porcine proliferative enteritis in specific-pathogen-free pigs 总被引：2，自引：0，他引：2
Thirty-three, 10-week-old, specific-pathogen-free pigs were randomly allotted to 3 treatment groups: group 1--intragastrically given homogenized intestinal mucosa (crude inoculum) from pigs with naturally occurring proliferative enteritis; group 2--given cultures of Campylobacter sputorum subsp mucosalis; and group 3--controls. One pig from each group was killed 4, 7, 10, 14, 18, 21, 24, 28, 31, 36, and 38 days after inoculation. The earliest intestinal lesion observed in groups 1 and 2 was leukocytic exudate within crypt lumina and focal inflammation of the surrounding lamina propria. The lesions occurred primarily over ileal aggregated lymphoid nodules (Peyer's patches). These changes were followed by focal proliferation of immature crypt epithelial cells and infiltration of increasing numbers of macrophages into the lamina propria. Campylobacter sp-like organisms were observed within the cytoplasm of affected epithelial cells by light and electron microscopies. Lesions progressed to diffuse crypt cell proliferation, elongation of crypts, and loss of villi. Mucosal necrosis was not a prominent feature. 相似文献
8.
Serological diagnosis of the porcine proliferative enteropathies: implications for aetiology and epidemiology 总被引：4，自引：0，他引：4
Campylobacter mucosalis and C hyointestinalis have been associated with the proliferative enteropathies of pigs. An examination of the antibody response to these organisms and to the intracellular campylobacter-like organism was undertaken. Antibody to the campylobacter-like organism was predominantly IgM, short lived, and could be detected by an immunofluorescence test using bacteria released from lesions as antigen. The majority (75 per cent) of pigs with proliferative enteropathy at necropsy were antibody positive and a small number (4 per cent) of pigs in which lesions were not observed were found to have antibody. Antibody appeared to be correlated with the presence of lesions rather than with exposure to infection and was independent of the presence of antibody to C mucosalis or C hyointestinalis. In natural outbreaks of the disease antibody to the campylobacter-like organism was more prevalent than clinical signs in the affected animals. 相似文献
9.
T Ohya M Nakazawa 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(5):1031-1033
Cytotoxin production by Campylobacter species isolated from proliferative enteropathy in swine was examined. Twenty-one of 29 strains of C. hyointestinalis, 10 of 27 strains of C. mucosalis and 10 of 10 strains of C. coli were cytotoxin positive. By the gel filtration chromatography of C. hyointestinalis culture filtrate, cytotoxin activities were observed in two peaks (fraction I and fraction II). Most of the cytotoxic activities lay in fraction I, which is heat-labile, trypsin-sensitive and the molecular weight was estimated at 40,000. On the other hand, fraction II cytotoxin was heat-stable, trypsin-insusceptible and molecular weight was approximately 1,000. 相似文献
10.
Gnotobiotic pigs were dosed orally with Campylobacter sputorum subspecies mucosalis, either alone, or combined with rotavirus or non-pathogenic Escherichia coli and Streptococcus bovis to study the behaviour of C s mucosalis in defined conditions, to assess intracellular parasitism of enterocytes by C s mucosalis, and if possible to establish an experimental model of porcine intestinal adenomatosis. C s mucosalis colonised the gut of gnotobiotic pigs, persisting for up to 47 days after infection, but did not induce adenomatosis. Despite evidence of limited penetration of the mucosa up to two days after infection, the majority of C s mucosalis remained in the gut lumen. Rotavirus did not enhance invasion of enterocytes by C s mucosalis. The presence of E coli and S bovis caused an increase in the total numbers of C s mucosalis in the gut, but did not affect their distribution. Thus C s mucosalis was largely non-pathogenic in gnotobiotic pigs. 相似文献
11.
Experimental reproduction of porcine proliferative enteritis 总被引：3，自引：0，他引：3
Conventional crossbred pigs from different sources and of different weights were examined for susceptibility to porcine proliferative enteritis. The ileal mucosa of pigs with the disease was emulsified and suspended in Mueller-Hinton broth. Pigs weighing 15, 120 and 200 lb (6.8, 54.5 and 91 kg) (four pigs per group) were stressed and inoculated orally with 80 ml of emulsified proliferative ilea. Severe lesions of porcine proliferative enteritis were detected in three of the four pigs weighing 6.8 kg. Mild lesions were detected in two of the four pigs in each of the other two groups. Gross lesions consisted of reticulation of the serosa, and hyperaemia and thickening of the mucosa with either fibrin or blood clots adherent to the mucosal surface. Inflammation, numerous mitotic figures and epithelial cell proliferation were observed microscopically in the crypts. Silver stained sections revealed numerous comma-shaped organisms in the crypts of infected epithelial cells. Using this method, serial reproduction of the disease was accomplished through the passage of fresh and previously frozen inocula. The virulence of the freshly prepared inoculum increased with passage through the host, whereas the inoculum prepared from tissue that had previously been frozen showed a decrease in infectivity and virulence. These data provide strong evidence for the infectious nature of this disease. 相似文献
12.
胞内劳森菌为严格细胞内寄生的无芽孢细菌,革兰氏染色阴性,抗酸染色阳性。主要感染3~20周龄猪而引起"猪增生性肠炎",临床表现慢性间歇性下痢或急性出血性下痢,排焦油样黑色粪便或血便。病理变化为小肠后段和结肠前段肠黏膜层增厚隆起,形成特征性分枝状皱折,肠腺上皮剧烈增生,形成畸形排列的分枝状肠腺。本病可进行流行病学、临床特征、病原学、病理学、血清学、分子生物学诊断,并需要与猪痢疾、猪梭菌性肠炎、仔猪副伤寒等病进行临床鉴别。本病的防控,应从猪群管理、引种、消毒、药物预防等方面考虑,接种疫苗是行之有效的措施。 相似文献
13.
An outbreak of proliferative haemorrhagic enteropathy (PHE) occurred in two epidodes and affected 372 adult pigs in the breeding units of a minimal disease piggery; 186 pigs died. In the initial episode breeding sows and boars of all ages were affected, suggesting infection of a fully susceptible population. Animals involved in the first episode of the disease did not show clinical symptoms at a later date and further clinical cases occurred only in animals introduced into the breeding population. Antibiotic feed medication was an effective method of prophylaxis. Bacteria resembling Campylobacter sputorum subspecies mucosalis were isolated from the intestinal mucosa of affected animals. 相似文献
14.
G H Lawson A C Rowland L Roberts G Fraser E McCartney 《Research in veterinary science》1979,27(1):46-51
This study indicates that viable Campylobacter sputorum subsp mucosalis are not present or are present in small numbers in the mucosa of pigs dying of proliferative haemorrhagic enteropathy. The changes present in the mucosa are similar to those seen in pigs recovering from adenomatosis and the evidence obtained indicates that the intracellular organisms observed in this condition are indeed mucosalis. The presence of large amounts of IgA in the altered tissue of both proliferative haemorrhagic enteropathy and porcine intestinal adenomatosis indicates that the failure to recover bacteria may be immunologically mediated but is not simply related to the presence or absence of antibody in the respective conditions. 相似文献
15.
Antisera against a number of Campylobacter species were used in immuno-histochemical and -cytochemical studies on cases of porcine intestinal adenomatosis. Avidin-biotin-complex (ABC) and streptavidin immunoperoxidase methods were used on formalin-fixed, paraffin-embedded and frozen sections. Protein A gold method was used on formaldehyde fixed and frozen sections for immuno-cytochemistry. The antisera used were raised in rabbits by subcutaneous or intravenous injection of living or formalin treated organisms. Anti-sera against different serotypes of the thermotolerant, catalase positive campylobacters, Campylobacter jejuni and Campylobacter coli, gave positive reactions in the immuno-histochemical studies. The staining was found in intestinal epithelial cells both in the ileum and in the colon and was restricted to the apical cytoplasm of adenomatous epithelial cells. The staining had a granular pattern, the positive structures sometimes having the shape of Campylobacter. Epithelial cells in areas with normal differentiation of goblet cells did not stain. In contrast, no staining resulted with antisera against Campylobacter sputorum subsp. mucosalis and Campylobacter hyointestinalis. Immuno-cytochemistry, using antisera against Campylobacter jejuni, showed that the positive staining in altered epithelial cells were restricted to intracellular organisms having a structure resembling Campylobacter spp. 相似文献
16.
M L van der Walt B T Spencer R K Loveday 《The Onderstepoort journal of veterinary research》1988,55(3):165-168
The first isolations of Campylobacter mucosalis in South Africa are described. Isolations were made from a 6-week-old weaner pig with necrotic enteritis and from 2 gingival swabs of suckling piglets from herds with histories of porcine intestinal adenomatosis. The isolates were serologically identified as being serotype A strains. 相似文献
17.
猪增生性肠炎的研究进展 总被引：1，自引：1，他引：0
猪增生性肠炎（porcine proliferative enteritis,PPE）,又称猪增生性肠病（porcine roliferative nteropathy,PPE）,是以回肠和结肠隐窝内未成熟的肠细胞发生腺瘤样增生为特征的猪的一种肠道综合症。本文主要概述其痛原学、流行病学、发病机理、临床症状、病理变化、诊断以及防治等方面的研究现状。 相似文献
18.
The distribution of enzymes and laminin was examined in ileal tissue from pigs suffering from intestinal adenomatosis to reveal the nature of the lesion. A disruption of the normal and specific pattern of distribution was found. Thus, the normal ileal epithelium was characterised by brush border enzymes: alkaline phosphatase, magnesium-dependent adenosine triphosphatase (Mg-ATPase), fluoride resistant acid phosphatase and 5'-nucleotidase; enzymes of the basolateral border: Mg-ATPase; and cytoplasmic enzymes: beta-glucuronidase, non-specific esterase and acid phosphatase. Subepithelial fibroblasts seemed to be characterised by 5'-nucleotidase. Laminin was present as a continuous band under the surface and crypt epithelium, somewhat thicker in the former. In contrast, the branching proliferating crypts of intestinal adenomatosis largely lacked enzymes characteristic of both villus and crypt cells. Reactions for the subepithelial components, laminin and fibroblasts were also reduced. The deficient differentiation of the epithelial as well as subepithelial components in porcine intestinal adenomatosis distinguish the condition from crypt hyperplasia and indicate an adenoma-like character. 相似文献
19.
Enteric campylobacter infection in gnotobiotic calves and lambs 总被引：1，自引：0，他引：1
Gnotobiotic calves and lambs were infected orally with Campylobacter jejuni, C coli or C hyointestinalis to assess pathogenicity. All animals were successfully colonised and excreted mucoid faeces but showed no other clinical signs. Campylobacters colonised the large intestine better than the small intestine, in which bacterial numbers decreased with time after infection. Campylobacters were found occasionally in the lumen of crypts in close proximity to epithelial cells and included in a mucus-like material. Lesions were mostly in the large intestine in calves whereas in lambs they were present in the ileum. In animals inoculated with C jejuni or C coli scattered crypt abscesses, focal inflammatory infiltrates in the lamina propria and goblet cell discharge were found. In lambs inoculated with C hyointestinalis only minor changes were found in the small intestine. Serum antibody response was either absent or present at a low level only from the 19th day after infection. 相似文献
20.
Enterocecocolitis associated with intraepithelial Campylobacter-like bacteria in rabbits (Oryctolagus cuniculus) 总被引：1，自引：0，他引：1
We examined 28 suckling, weanling, and young adult rabbits with lethargy, inappetence, and mucinous, semifluid feces. Sixteen of the rabbits had intestinal lesions. In eight of these rabbits, the primary changes were multifocal to diffuse epithelial proliferation and accumulation of lymphocytes, macrophages, or both in the lamina propria of the small intestine, cecum, and sacculated colon. In two of these rabbits, the accumulation of macrophages in the lamina propria was extensive. The other eight rabbits had erosive and suppurative cecocolitis, and four of the rabbits with proliferative lesions also had suppurative cecocolitis. In Warthin-Starry-stained sections of affected intestine, curved or spiral bacteria were visible within degenerated or hyperplastic epithelium, in luminal exudate, or in both. Such organisms were sparse or not found in the other 12 rabbits, which did not have intestinal lesions. The bacteria ultrastructurally resembled intraepithelial Campylobacter-like bacteria previously observed in proliferative enteritis in a variety of species and in acute typhlitis in young rabbits. In immunofluorescence tests, Campylobacter-like bacteria in epithelial cells, crypt lumina, and in luminal exudates in both proliferative and erosive lesions bound monoclonal antibodies and polyclonal antisera prepared against intracellular bacteria found in proliferative enteritis in pigs, hamsters, and ferrets. These observations indicate that a condition similar to proliferative enteritis of swine, hamsters, and other species also occurs in laboratory rabbits. 相似文献