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1.
Mice immunized with an aromatic-dependent (aro-) S. dublin strain CS101 by either the intraperitoneal (i.p.) or oral route, were protected against oral challenge with a virulent S. dublin strain CS90, the degree of protection being the greatest when mice had received 3 immunizing doses at weekly intervals. Mice immunized with an aromatic-dependent (aro-) S. typhimurium strain CS332 by the i.p. or oral routes were protected against challenge with virulent S. dublin strain CS90 at 1 or 2 weeks but not at 3 or 4 weeks post-immunization. Mice immunized with 1 dose of aro- S. dublin strain CS101 by the i.p. route developed low levels of lipopolysaccharide (LPS) and flagellin-specific antibody but no delayed-type hypersensitivity (DTH) whereas those immunized with 2 or 3 doses developed significantly higher antibody titres and DTH. In contrast, mice immunized by the oral route developed neither significant antibody response nor DTH. The aro- S. dublin strain CS101 could not be detected beyond day 28 post-inoculation in visceral organs including liver, spleen, mesentery, small intestine, caecum or large intestine of mice inoculated by the i.p. route or in mice inoculated by the oral route with the exception of day 42 post-inoculation. Challenge of mice previously immunized with 3 doses of the aro- S. dublin strain CS101 by the i.p. or oral route with virulent S. dublin strain CS90 resulted in their rapid clearance from the above visceral organs. Calves immunized with the aro- S. dublin strain CS101 by either the intramuscular (i.m.) or oral routes were significantly protected against oral challenge with virulent S. dublin strain CS90. In contrast to the observations in mice, somatic (O) and flagellar (H) antibody titres of calves immunized by either route were negligible as were anti-LPS antibody titres. However, flagellin-specific antibody titres were higher in calves immunized by the i.m. than the oral route. These results indicate that the protection observed in immunized mice or calves against oral challenge with virulent S. dublin was unlikely to have been mediated by humoral salmonella-specific immune mechanism(s).  相似文献   

2.
The aim of this investigation was to determine the development and duration of protection in mice or sheep immunised with aromatic-dependent (aro-) Salmonella typhimurium strain CS332, by either parenteral or oral routes. Immunisation of mice by the intraperitoneal or sheep by the intramuscular routes was found to impart protection against oral challenge with the virulent parent S typhimurium strain CS94 as early as seven days after immunisation. In contrast, when immunisation was carried out by the oral route, protection was not evident until three weeks after immunisation. Regardless of the route of immunisation, mice were still partially protected at three months and were fully susceptible at six months after immunisation. In sheep, protection persisted for six months but not 12 months after immunisation. Only parenterally immunised mice and sheep developed high ELISA and, or, agglutinating antibody titres, and cutaneous delayed-type hypersensitivity (DTH) at three weeks after immunisation. Although both antibody and DTH were detectable three months after immunisation of mice with aro- S typhimurium strain CS332, none was detected at six months. Antibody measured by agglutination and ELISA was detectable six months after immunisation in sheep, although no DTH was evident. At 12 months after immunisation low levels of anti-LPS antibody (measurable by ELISA only) were detected in sheep immunised by the intramuscular route.  相似文献   

3.
The present study was undertaken to determine the prevalence and distribution of Salmonella from apparently healthy slaughtered camels in Eastern Ethiopia. A total of 714 samples (faeces, mesenteric, lymph nodes, spleen, liver, abdominal and diaphragmatic muscles) from 119 slaughtered camels were analysed. Salmonellae were detected from 116 (16.2%) of the 714 samples examined. Eighteen (15.1%) faeces, 19 (15.9%) mesenteric lymph nodes, 14 (11.8%) livers and 17 (14.3%) spleen samples (n = 119 for each) were positive for Salmonella. Salmonellae were found in 20.1% of the abdominal and diaphragmatic muscles. A total of sixteen different serotypes were identified of which Salmonella saintpaul (38.8%) and S. braenderup (22.4%) were the most prevalent followed by S. muenchen (8.6%), S. kottbus (6.0%) and S. havana (5.2%). Other serotypes, including S. typhimurium, S. heidelberg and S. enteritidis were also detected from Ethiopian camels.  相似文献   

4.
The minimum number of doses of a live aromatic dependent (aro-) Salmonella typhimurium vaccine strain (SL1479), given by the intramuscular, oral or subcutaneous route required to protect sheep from experimentally-induced clinical salmonellosis, was determined. A significant reduction in mortalities and diarrhoea occurred in those sheep immunised with one or 2 intramuscular doses or 2 subcutaneous doses. On the other hand, sheep immunised with one subcutaneous dose were not protected. Immunisation with one or 2 oral doses also resulted in a significant reduction in mortality, although reduction in the prevalence of severe diarrhoea was less consistent. Sheep immunised with a single intramuscular dose of aro- S. typhimurium developed high levels of serum antibodies and significant delayed-type cutaneous hypersensitivity response to homologous Salmonella lipopolysaccharide and flagellin, whereas those with a single oral dose did not. It was concluded that immunisation of sheep with a single oral or intramuscular dose of live aro- S. typhimurium reduced mortalities and the prevalence of diarrhoea in sheep due to infection with virulent S. typhimurium.  相似文献   

5.
Colostrum-deprived, neonatal, 2 days old pigs were inoculated with the attenuated HT-/SK or the virulent 90HS strain of porcine parvovirus (PPV) by the oral or subcutaneous route and sacrificed 2, 4 or 6 days after inoculation. Then, comparison was made on viral multiplication in pigs between the two strains. Pigs inoculated with the HT-/SK strain showed no detectable viremia or HI antibody responses against PPV within 6 days after inoculation. Only in pigs inoculated by the subcutaneous route, a small amount of virus was recovered from the spleen, liver, or mesenteric lymph nodes. These viruses were distinguished from the parental virulent 90HS strain, as examined for rct maker in vitro. When pigs were inoculated with the virulent 90HS strain, viremia appeared in all of them 1 day after inoculation and continued for up to the sacrificed day. Moreover, a considerable amount of virus was also detected from all tissues, including brain, lung, liver, spleen, pancreas, small intestine, and lymph node tissues, in all pigs tested. HI antibodies were first detected 6 days after inoculation.  相似文献   

6.
AIMS: To determine immune responses, and the localisation and persistence of Mycobacterium bovis bacille Calmette-Guérin (BCG) in gut-associated lymphoid tissues (GALT) and other organs in possums vaccinated orally with lipid-formulated BCG vaccine. To determine the duration of excretion and longevity of survival of BCG in the faeces of vaccinated animals. METHODS: Possums (n=28) were vaccinated with lipid-formulated BCG (1 x 10(8) colony forming units (cfu) of formulated BCG) by the oral route. Control possums (n=17) were fed oral bait pellets containing formulation medium only. Possums were sacrificed at 3 days and at 1, 3, 6 and 8 weeks after vaccination or ingestion of bait. Proliferation responses to bovine purified protein derivative (PPD) were measured in lymphocytes from blood and mesenteric lymph nodes (MLN) and samples of lung, spleen, liver, MLN and Peyer's patches (PP) were cultured for the presence of BCG. The number of BCG organisms excreted in faeces and the duration of excretion were determined in eight vaccinated possums and eight control possums over a 3-week period. In a separate experiment, a further six possums were vaccinated with oral BCG vaccine (5-10 x 10(8) cfu BCG/possum) and their faeces collected over 48-72 h, for culture of BCG. The longevity of survival of BCG in these faeces was determined by storing faecal samples (n=12) under three different conditions: in an incubator (22.5 degrees C), and conditions which simulated the forest floor and open pasture. A proportion (1-2 g) of these faecal samples was collected after storage for 1, 3, 5, 8 or 20 weeks, and cultured for BCG. RESULTS: Possums vaccinated orally with BCG vaccine showed strong proliferation responses to bovine PPD in peripheral blood lymphocytes at 6-8 weeks post-vaccination (p.v.). Positive lymphocyte proliferation assay (LPA) responses to bovine PPD were first evident in MLN at 3 weeks p.v. BCG was cultured from MLN and PP in a proportion of animals at 3-8 weeks p.v. BCG was not cultured from sections of spleen, lung or liver at any time p.v. BCG was recovered in low to moderate numbers from the faeces of vaccinated possums for up to 7 days, and maximal numbers were cultured in faeces collected 48-72 h p.v. After storage for 1 week, BCG was cultured from all faecal samples placed in the incubator and from a proportion of faeces exposed to conditions similar to those on the forest floor and pasture. With the exception of one faecal sample stored under forest floor conditions which was culture-positive for BCG at 3 and 5 weeks, BCG was not cultured from any other faecal sample stored for more than 1 week. CONCLUSIONS: Ingestion of oral BCG vaccine by possums was associated with the development of strong cell-mediated immunity in both blood and MLN. Following oral vaccination with BCG, the organisms were localised and persisted in GALT but did not spread to the spleen, liver or lungs. BCG was shed in low to moderate numbers in the faeces for up to 7 days p.v. The viability of BCG excreted in faeces decreased rapidly, particularly when faeces were exposed to an open pasture environment. Oral vaccination of possums with formulated BCG is unlikely to result in undue contamination of the environment with BCG.  相似文献   

7.
Eight calves were immunized with live auxotrophic Salmonella typhimurium mutants (aro -SL 1479, gal E 3821) and twelve calves with phenol-killed whole-cell S. typhimurium vaccine, respectively. The clinical status of the animals was followed and serial reisolation of vaccine and challenge strains from faeces was attempted. The immunization of calves with the live aro- auxotrophic S. typhimurium SL 1479 mutant proved to be unsuitable due to the death of calves after revaccination. The calves immunized with live auxotrophic gal E S. typhimurium CCM 3821 mutant proved to be protected against challenge with virulent S. typhimurium 4/5 strain administered orally at a dose of 10(6) colony forming units (CFU). The postvaccination complications showed serious shortcomings. The immunization of calves with three doses of whole-cell inactivated vaccine containing 5 strains of S. typhimurium was effective against oral challenge with virulent S. typhimurium 4/5 at a dose of 10(6) CFU.  相似文献   

8.
The concentration of enrofloxacin in plasma, intestinal tissue, lymph nodes and intestinal contents was investigated in healthy pigs after oral (p.o.) and intramuscular (i.m.) administration of a single dose of 2.5 mg/kg bw. Tissue and content samples were collected from jejunum, ileum, caecum and colon from pigs killed at 2, 3 and 6 h after dosing. Intramuscular administration resulted in significantly higher concentrations in plasma, intestinal tissue and lymph nodes at 2 h but not at 3 or 6 h compared with p.o. administration. The absorption and distribution phase was longer after oral administration, and maximum concentrations in tissue and plasma were determined later than after i.m. administration. No difference between route of administration was observed in the intestinal content. Enrofloxacin concentrations in faeces during a 5-day dosing regimen with i.m. and p.o. administration were determined by both HPLC and bio-assay. Higher concentrations were found after i.m. administration during the first day, but the difference was not significant after 2 days. The biologically active concentrations determined by bio-assay constituted 48-75% of the total concentrations determined by HPLC. On the basis of these results it was concluded that in order to ensure an immediate high concentration of enrofloxacin, and thereby avoid an initial selection for resistant mutants, the intramuscular route seems to be preferable to the oral route.  相似文献   

9.
Hybrid swine (Landrace x Pietrain) aged 3-4 weeks were immunized twice at an interval of 3 weeks solely by the oral route and by the oral/parenteral route to evaluate the efficacy of a live S. Typhimurium vaccine. In each experiment a control group was run without vaccination. The animals were challenged at the age of 8-10 weeks by oral test infection with a labelled S. Typhimurium DT 104 strain. An ELISA was used to establish the presence of antibodies to S. Typhimurium in serum samples, coupled with clinical investigation. The presence of the challenge strain in the ileal and caecal mucosa and in the ileocolic lymph nodes was investigated quantitatively using the Koch plating method to determine the degree of colonization of those organs at the time of slaughter. The clinical course of disease was used to assess the success of vaccination. However, it was not possible to trigger, in a reproducible manner, clinical signs of disease in unvaccinated animals through infection. The vaccinated animals had a significantly lower (p < 0.05) colonization of the ileal and caecal mucosa than the unvaccinated animals. This was also seen to a lesser degree for the ileocolic lymph nodes.  相似文献   

10.
The major objective of the present study was to determine whether oral immunization with a live aromatic-dependent strain of Salmonella typhimurium (SL1479) was capable of stimulating an intestinal immune response in sheep similar to that induced by combined intraperitoneal injection followed by oral boosting. The results showed that repeated oral immunization was incapable of stimulating an anti-flagella antibody containing cell (ACC) response in the lamina propria of the intestine even though primary oral administration of 5 x 10(9) live SL1479 gave rise to an ACC response in intestinal lymph which was predominantly of the IgM isotype. ACC reached a peak 9-10 days after oral administration when ACC comprised 0.5-1% of total lymphocytes in lymph. An ACC response of similar isotope specificity also occurred in popliteal prefemoral lymph of unprimed sheep following regional subcutaneous injection of SL1479. Oral administration of SL1479 to orally primed sheep did not reinvoke an ACC response in lymph although IgG1-ACC were observed in medullary cords of mesenteric lymph nodes of sheep 6-8 days after the booster dose of SL1479. The results suggest that the protective immunity elicited by oral administration of SL1479 cannot be attributed to induction of a local intestinal antibody production.  相似文献   

11.
We examined patterns of lymphocyte localization in female dairy cattle following infusion of 51Cr-labeled autologous lymphocytes prepared from surgically excised mammary or ileal mesenteric lymph nodes. Labeled lymphocytes prepared from mammary lymph nodes were recovered in proportionally high numbers from mammary and prescapular lymph nodes, and in low numbers from intestinal mesenteric nodes. This pattern was observed in both heifers and lactating cows. In contrast, labeled lymphocytes prepared from ileal mesenteric lymph nodes of lactating cows were recovered in proportionally high numbers from intestinal mesenteric nodes, and in low numbers from mammary and prescapular nodes. These findings, when compared with previous results in sheep and swine, support the hypothesis that lymphocytes do not migrate efficiently between the gut and mammary gland of ruminants.  相似文献   

12.
AIMS: To determine immune responses, and the localisation and persistence of Mycobacterium bovis bacille Calmette-Guérin (BCG) in gut-associated lymphoid tissues (GALT) and other organs in possums vaccinated orally with lipid-formulated BCG vaccine. To determine the duration of excretion and longevity of survival of BCG in the faeces of vaccinated animals.

METHODS: Possums (n=28) were vaccinated with lipid-formulated BCG (1 x 10 8 colony forming units (cfu) of formulated BCG) by the oral route. Control possums (n=17) were fed oral bait pellets containing formulation medium only. Possums were sacrificed at 3 days and at 1, 3, 6 and 8 weeks after vaccination or ingestion of bait. Proliferation responses to bovine purified protein derivative (PPD) were measured in lymphocytes from blood and mesenteric lymph nodes (MLN) and samples of lung, spleen, liver, MLN and Peyer's patches (PP) were cultured for the presence of BCG. The number of BCG organisms excreted in faeces and the duration of excretion were determined in eight vaccinated possums and eight control possums over a 3-week period. In a separate experiment, a further six possums were vaccinated with oral BCG vaccine (5–10 x 10 8 cfu BCG/possum) and their faeces collected over 48–72 h, for culture of BCG. The longevity of survival of BCG in these faeces was determined by storing faecal samples (n=12) under three different conditions: in an incubator (22.5°C), and conditions which simulated the forest floor and open pasture. A proportion (1–2 g) of these faecal samples was collected after storage for 1, 3, 5, 8 or 20 weeks, and cultured for BCG.

RESULTS: Possums vaccinated orally with BCG vaccine showed strong proliferation responses to bovine PPD in peripheral blood lymphocytes at 6–8 weeks post-vaccination (p.v.). Positive lymphocyte proliferation assay (LPA) responses to bovine PPD were first evident in MLN at 3 weeks p.v. BCG was cultured from MLN and PP in a proportion of animals at 3–8 weeks p.v. BCG was not cultured from sections of spleen, lung or liver at any time p.v. BCG was recovered in low to moderate numbers from the faeces of vaccinated possums for up to 7 days, and maximal numbers were cultured in faeces collected 48–72 h p.v. After storage for 1 week, BCG was cultured from all faecal samples placed in the incubator and from a proportion of faeces exposed to conditions similar to those on the forest floor and pasture. With the exception of one faecal sample stored under forest floor conditions which was culture-positive for BCG at 3 and 5 weeks, BCG was not cultured from any other faecal sample stored for more than 1 week.

CONCLUSIONS: Ingestion of oral BCG vaccine by possums was associated with the development of strong cell-mediated immunity in both blood and MLN. Following oral vaccination with BCG, the organisms were localised and persisted in GALT but did not spread to the spleen, liver or lungs. BCG was shed in low to moderate numbers in the faeces for up to 7 days p.v. The viability of BCG excreted in faeces decreased rapidly, particularly when faeces were exposed to an open pasture environment. Oral vaccination of possums with formulated BCG is unlikely to result in undue contamination of the environment with BCG.  相似文献   

13.
In homologous and heterologous challenge trials using calves 相似文献   

14.
Seven experiments including a total of 47 pigs, 11 wild boars, 26 rabbits, 10 hares and 16 sheep were carried out to assess the efficacy, safety and transmission of the Chinese vaccine strain of the classical swine fever virus (CSFV) administrated by the oral route. Within 3 weeks after oral vaccination, a clear seroconversion occurred in the pigs. Six weeks after vaccination, vaccinated pigs were fully protected against a virulent challenge. The C-strain was not isolated from tonsils, spleen, lymph nodes, thymus, saliva, urine and faeces of pigs within 4 days after oral vaccination. In one experiment, susceptible pigs were placed in direct contact with vaccinated pigs. None of these contact-exposed pigs became serologically positive for CSFV antibodies. It is concluded that the C-strain induces protection in pigs when administrated by the oral route and is not shed by vaccinated pigs. Serum anti-CSFV antibodies developed in seven out of eight wild boars vaccinated by the oral route. No vaccine virus was detected in the spleen and tonsils of these animals. The results in wild boar were in accordance with those obtained in domestic pigs. Sheep did not show any clinical signs after oral vaccination while rabbits had moderate hyperthermia and growth retardation. No clinical response to oral immunisation in hares was detected. At the end of the experiment, no sheep had detectable serum antibodies against CSFV, whereas a few vaccinated rabbits and hares became seropositive. None of the contact-exposed rabbits and hares seroconverted. These data indicate that the C-strain is safe for sheep and as expected, moderately or not pathogenic for rabbits and hares. These efficacy and safety studies on oral vaccination with the C-strain under experimental conditions provide essential information for further studies in wild boars under experimental and field conditions, including assays with baits to control a CSF epidemic.  相似文献   

15.
From a pathological examination of the intestinal tracts of 1590 goats killed at slaughterhouses in the Fars Province of Iran, 59 cases (3.71%) were suspected, on gross examination, of having paratuberculosis. The diagnosis was confirmed by histopathological study and Ziehl-Neelsen staining of direct smears of rectal faeces. On the basis of severity of involvement of the terminal ileum and mesenteric lymph nodes, the microscopic lesions were classified to mild, moderate and severe forms. Caseous necrosis and calcification were observed only in the mesenteric lymph nodes. High numbers of acid-fast organisms were present in the epithelioid macrophages of the intestine but were inapparent or sparse in the mesenteric lymph nodes. On microscopic examination, 13.5% of the suspected animals were found to have paratuberculosis, in comparison with 3.38% by direct faecal smears. In addition, 30.5% and 15.3% of the animals were diagnosed as having eosinophilic enteritis and linguatulosis, respectively. These findings stress the importance of a careful histopathological examination of the intestines and mesenteric lymph nodes for the diagnosis of paratuberculosis in goats.  相似文献   

16.
One jejunal and one caecal lymph node were sampled from each of 50 cows, 40 yearling cattle, 25 sheep, 20 lambs and 45 pigs after slaughter. Salmonella, Clostridium perfringens and Staphylococcus aureus , all organisms which cause food poisoning in man, were sought by direct plating methods. The samples were also enriched and cultured for Salmonella. Organisms were cultured from 208 (58%) of the 360 lymph nodes; aerobic plate counts yielded up to 25,000 organisms per gram of tissue, although from most infected samples less than 1000 organisms per gram were cultured. Salmonella was isolated directly from 5% of samples, with counts up to 1,500 per gram. After enrichment Salmonella was isolated from nodes taken from 15 cows, 2 yearling cattle, one sheep and 8 pigs. Cl. perfringens was isolated from the caecal nodes of 2 yearling cattle and 2 pigs; S. aureus was not isolated from any sample. It was concluded that mesenteric lymph nodes may be a significant reservoir of Salmonella for transfer to meat and meat products.  相似文献   

17.
为研究不同毒力的PRRSV对仔猪肺脏和外周免疫器官损伤的差异,本实验分别采用PRRSV变异株(HuN4株)和PRRSV经典株(CH-1a株)感染35日龄健康的断奶仔猪,并在感染后0 d、3 d、7 d、10 d和14 d各迫杀3头,检测肺、颌下淋巴结、肠系淋巴结、腹股沟淋巴结、扁桃体和脾脏的病毒载量及病理变化情况,同时检测血清中抗PRRSV的抗体水平。结果表明:感染后3 d肺脏及各免疫器官可检测到病毒,HuN4感染组病毒载量比CH-1a感染组病毒载量高1 000倍;HuN4感染组病毒载量峰值出现在感染后10 d,而CH-1a感染组维持着较低水平的病毒载量。组织病理学检测显示HuN4感染组淋巴结内淋巴细胞显著减少,呈空泡状;CH-1a感染组淋巴结内淋巴细胞轻度减少,呈星隙状。本实验表明HuN4株比CH-1a株对肺和外周免疫器官造成更严重的损伤。  相似文献   

18.
The sites of early viral replication in feline infectious peritonitis   总被引：2，自引：0，他引：2  
The sites of early replication of feline infectious peritonitis virus were studied following oral inoculation of specific-pathogen-free (SPF) cats with virus grown in cell cultures. Viral antigen was first detected by immunofluorescence in the tonsils and small intestine within 24 h of inoculation, and was later found in caecum, colon, mesenteric lymph nodes and liver. However, histological changes in the gut did not appear until relatively late in the course of infection. Virus was recovered from the oropharynx and the faeces from as early as the second or third day after inoculation, and shedding continued until euthanasia.  相似文献   

19.
Virus was recovered from the faeces of chickens infected at three or four weeks of age for more than 20 weeks after infection with commercial vaccines or with the T strain of avian infectious bronchitis virus (IBV). Virus was not recovered from the trachea, liver, spleen, bursa or kidneys of T strain infected birds longer than 29 days after infection at which point IBV was recovered from the bursa of a single infected bird. In a subsequent experiment IBV was recovered from the caecal lymph nodes and faeces of one of five birds 14 weeks after infection with a commercial vaccine but no virus was isolated from the trachea, kidneys, duodenum, bursa, ovaries or testes of any of the five birds at this time.  相似文献   

20.
The possibility of persorption of prefixed bovine serum albumin-coated sheep erythrocytes (BSA-SEs) from mucous epithelial cells and its mechanisms were investigated in rats orally immunized by BSA for 14 consecutive days. On the day after the final oral immunization, the rats were duodenally perfused by BSA-SEs or non-coated SEs. BSA-SEs were also duodenally perfused in non-immunized rats. Thirty min after perfusion, BSA-SEs were significantly more engulfed by late-apoptotic-stage villous columnar epithelial cells in the orally immunized rats than those in other experiments. The specific antibody (SpAb) was detected on the surfaces of BSA-SEs in rats with oral immunization. In Peyer's patches of all animals, no SEs reached the follicle-associated epithelium, because of the close attachment of follicle-associated intestinal villi and the thick mucous layer. BSA-SEs were more frequently persorbed into portal blood in the orally immunized rats than in other rats. Small numbers of BSA-SEs or SEs were detected in the systemic blood of all animals. BSA-SEs were also histologically found in the blood vessels of the liver, but not in mesenteric lymph nodes. These findings suggest that sensitized antigenic particulates are taken up by late-apoptotic-stage villous columnar epithelial cells in the small intestine and are finally persorbed into the systemic blood circulation. The uptake of antigenic particulates might be mediated by its luminal SpAb.  相似文献   

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