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1.
Pigs were immunised intraperitoneally with ovalbumin in Freund's complete adjuvant and subsequently challenged intratracheally with ovalbumin. The results show that the group receiving two intratracheal challenges had a significantly greater antiovalbumin-containing cell response in the lamina propria of the respiratory tract. With intraperitoneal immunisation or intratracheal challenge alone the response was negligible. The immunoglobulin isotype of the anti-ovalbumin containing cells was predominantly IgG. There was also a substantial antibody containing cell response in the lung which was also IgG. These findings are discussed in relation to immunity within the porcine respiratory tract.  相似文献   

2.
Experimental immunisation of lambs against pneumonic pasteurellosis   总被引:1,自引:0,他引:1  
Methods of immunising lambs against pneumonic pasteurellosis, caused by several serotypes of Pasteurella haemolytica, were assessed in specific pathogen free lambs. Lambs were vaccinated intramuscularly with sodium salicylate extract (SSE) of P haemolytica, either alone or in combination with heat-killed organisms (HKO). SSE of P haemolytica type A1 protected vaccinated lambs against pneumonia resulting from challenge with the homologous serotype. SSE of type A2 also provided some protection but this was improved by vaccination with a combination of SSE and HKO.  相似文献   

3.
Pigs were immunised intraperitoneally with ovalbumin (OVA) in Freund's complete adjuvant and killed between 52 and 71 days later. Sera, bile and spleen and liver tissue were collected at slaughter. IgG and IgA OVA antibody in bile and serum were detected by ELISA, and IgG and IgA anti-OVA containing cells (AOCC) in tissue were observed using double fluorochrome labelling techniques. The results indicated few IgA AOCC in spleen or liver, but an elevated IgA OVA response in bile compared to serum relative to IgG. The results indicate selective transport of IgA OVA antibody from serum to bile relative to IgG.  相似文献   

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To introduce antigen to the respiratory mucosa, killed Actinobacillus pleuropneumoniae with quil A as adjuvant was administered to pigs as an aerosol. Immunisation by this aerosol induced a marked IgA response in the bronchoalveolar and nasal fluids, and in the serum. Following challenge with live bacteria two weeks after the last exposure to the aerosol, the immunised pigs were protected from the severe pleuropneumonia which developed in non-immunised pigs. The immunised pigs had lower antibody titres in the mucosal fluids and serum after exposure to the challenge. The immune response after experimental infection of non-immunised animals was a weak IgA antibody response in the bronchoalveolar and nasal fluids, whereas the systemic immune response after challenge included both IgA and IgG antibodies.  相似文献   

6.
Development of immunity after a single primary infection of Ascaris suum in pigs was investigated with regard to the worm population dynamics of a superimposed A. suum infection, host immune response and gross liver pathological changes. Group A was given a primary infection of 60,000 infective A. suum eggs and group B was left uninfected. Four weeks later both groups A and B were inoculated with 1,000 A. suum eggs, and subgroups were slaughtered 7, 14 and 21 days post challenge infection (p.c.i.). An uninfected control group C was slaughtered on day 21 p.c.i. The challenge worm recovery in group A was reduced compared to group B by 12%, 50% and 75% on day 7, 14 and 21 days p.c.i., respectively. In both groups was the expulsion of worms initiated between day 14 and 21 p.c.i. However, in group A the worms were recovered more posteriorly in the small intestine and 21 days p.c.i. the mean worm length was significantly shorter than in group B (p = 0.01). The results above were associated with significantly higher (p < 0.05) antibody response and higher eosinophil counts in group A compared to group B. The present results suggest that the larval growth and survival of a challenge infection are decreased, probably due to higher antibody and eosinophil attack during the migratory phase.  相似文献   

7.
Small and large intestines of seven specific pathogen-free lambs infected with cryptosporidia from calves with diarrhea were examined by scanning and transmission electron microscopy and by light microscopy. The small intestine was infected in all the lambs, and the cecum and colon in three. Small intestinal alterations were severe villous atrophy and dilatation of the crypts of Lieberkühn. Epithelial cross-bridging between contiguous villi caused much villous fusion. Epithelial cells constituting the bridges were connected by desmosomal junctions, and were continuous with the epithelial coverings of the associated villi. The lamina propria was heavily infiltrated with neutrophil leukocytes. Infected crypts in cecum and colon were dilated and devoid of mucus-secreting cells, while the ridges between crypts were hypertrophied, and the lamina propria was infiltrated by neutrophils. Cell vegetations with adherent bacteria were present in the surface intestinal epithelium of two lambs infected for 11 and 14 days, respectively. No adherent bacteria were seen in any site in lambs killed up to six days post-inoculation.  相似文献   

8.
Groups of five pigs were vaccinated at three to four weeks old with either formolised Treponema hyodysenteriae in oil adjuvant alone, formolised T hyodysenteriae in oil adjuvant plus formolised Campylobacter coli in oil adjuvant, or sterile medium in oil adjuvant (as a control). Each group was challenged four weeks after vaccination by oral dosing on two consecutive occasions with pure cultures of the homologous strain of T hyodysenteriae plus direct contact with two pigs exhibiting severe swine dysentery. The disease was observed in two of five pigs immunised with T hyodysenteriae alone, three of five pigs immunised with T hyodysenteriae plus C coli and all five controls; haemorrhagic diarrhoea was exhibited only by the control group. Each pig immunised with T hyodysenteriae (alone or with C coli) recovered spontaneously, whereas four controls died. Vaccination with T hyodysenteriae also markedly reduced the severity and duration of clinical signs and of weight loss. No differences were observed in response to challenge between pigs immunised with T hyodysenteriae alone and pigs immunised with T hyodysenteriae plus C coli.  相似文献   

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The prophylactic efficacy of a single oral dose of toltrazuril against coccidiosis (mixed Eimeria infections) in naturally infected lambs was evaluated in two experiments. Toltrazuril at 20 mg kg-1, given on Day 7 or Day 10 after turnout on pasture, proved to be highly efficacious in preventing clinical coccidiosis under Norwegian conditions. Toltrazuril reduced the oocyst output to very low levels, prevented the development of diarrhoea and improved weight gain during the first 4-5 weeks after treatment. Treatment on Day 7 was superior to treatment on Day 10 with respect to improving weight gain and preventing the development of soft faeces. Lambs treated with toltrazuril on Day 7 seemed to be as immune as untreated lambs to natural reinfections with coccidia later in the grazing season. In one of the experiments, natural infections with the nematode Nematodirus battus produced a coccidiosis-like disease in some lambs simultaneously with the outbreak of coccidiosis.  相似文献   

13.
Ewes were immunised intraperitoneally with ovalbumin and Brucella abortus in Freund's complete adjuvant, followed seven days later by intramammary immunisation in which ovalbumin was presented to one mammary gland and Brucella abortus to the other. Mammary tissue taken after a further seven days contained more antigen-specific plasma cells than ewes given intraperitoneal or intramammary immunisation alone. These cells were found predominantly in the specifically immunised gland and only a few were found in the contralateral gland. Most of these cells were of the IgG1 isotype. There was also an increase in the total number of IgG1- and IgG2-containing cells in mammary gland tissues of these ewes, indicating a non-specific response to immunisation. Following either intraperitoneal or intramammary immunisation there was also a significant increase in the number of antigen-specific IgA cells in the lamina propria of the jejunum. The gut response following intramammary immunisation alone was abrogated by chronic drainage of intestinal lymph but not mammary lymph. This suggests that antigen may relocate from the mammary gland to the intestine where an IgA response is generated from gut associated lymphoid tissue. These data provide evidence for interaction between the gut and mammary gland of sheep in response to antigen.  相似文献   

14.
Vitamin A deficiency: serum cortisol and humoral immunity in lambs   总被引:1,自引:0,他引:1  
Serum cortisol and antigen-specific and polyclonal immunoglobulin G (IgG) concentrations were measured to investigate the relationship between vitamin A status and immune function in lambs. Twenty-four 3-mo-old crossbred ewe lambs weighing approximately 10 kg were each fed 900 g/d of a carotene-deficient diet. The 12 control lambs also received a 100,000 IU oral dose of vitamin A palmitate every 2 wk. All lambs were given primary and secondary antigenic challenges. Lambs were slaughtered at the end of the secondary challenge period. Liver vitamin A concentrations were greater (P less than .001) in the control animals (69.5 vs 1.3 micrograms/g wet tissue). Both groups of lambs exhibited a similar growth response until d 105, after which daily gain of the control lambs exceeded (P less than .03) that of the A-deficient lambs. Polyclonal serum IgG concentrations were greater (P less than .05) in the A-deficient lambs on d 49 to 124 and on d 151 (P less than .10). Ovalbumin-specific serum IgG concentrations tended to be greater in the control lambs throughout the primary and secondary challenge periods. Control lambs had greater titers on d 164 (P less than .07) and d 190 (P less than .03). Vitamin A status appeared to have no consistent effects on serum cortisol concentrations. Spleen weights were greater (P less than .002) in the A-deficient lambs. Lungs from 11 of 12 A-deficient lambs contained abscesses, as opposed to 1 of 12 for the control lambs. Both polyclonal and antigen-specific IgG concentrations were affected by vitamin A status. Serum cortisol concentrations did not appear to mediate this effect.  相似文献   

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肠道黏膜免疫系统是仔猪体内最大的黏膜免疫器官,在识别和清除有害物质的过程中发挥着重要作用,同时能够对营养物质和肠道益生菌形成免疫耐受,与仔猪的健康关系最为密切。随着养殖业进入全面减抗、限抗的时代,养猪业面临巨大的挑战。仔猪肠道健康决定了猪场的生产效益,正确认识仔猪肠道免疫系统,科学调节肠道免疫,提高仔猪抗病能力,是决定养猪生产能否成功的重要因素。  相似文献   

16.
The nature of antigen and presence of adjuvant are major factors which influence the level of immune reactivity following immunisation. This study examines the quantity and isotype of antibody produced in ewes immunised with different proteins in combination with different adjuvants. Results using indirect ELISA assays show that animals immunised with keyhole limpet haemocyanin (KLH) in adjuvant produced lower levels (P less than 0.05) of immunoglobulin M (IgM) and had increased levels and persistence of immunoglobulin G1 (IgG1) compared with ewes immunised with antigen in saline (P less than 0.005). The anti-KLH immunoglobulin G2 (IgG2) titre was significantly higher in animals given oil-emulsion adjuvant than all other groups (P less than 0.005). Ewes were also immunised with bovine serum albumin (BSA) or BSA haptenated with trinitrophenyl (TNP) for the primary injection and carrier BSA alone for the secondary inoculation. Chemical haptenation of BSA antigen reduced primary IgM (P less than 0.005), IgG1 (P less than 0.005) and IgG2 (P less than 0.005) levels compared with animals immunised with pure BSA. There was an increased secondary anti-BSA IgM response in all animals first immunised with TNP-BSA (P less than 0.05). The class of anti-hapten antibody produced to TNP determinants was influenced by the degree of TNP haptenation of the carrier BSA. Mid-range molar ratios of TNP produced the strongest IgM, IgG1 and IgG2 anti-TNP responses compared with all other groups (P less than 0.01).  相似文献   

17.
Colostrum from ewes that had been repeatedly exposed to cestode infection, whether or not their immunity was boosted by vaccination with Taenia ovis, transferred a strong immunity to the lambs. Susceptible ewes, not recently exposed to tapeworm eggs, gave no protection to their lambs via the colostrum. There was no evidence that colostrum-deprived lambs were more susceptible to infection with T ovis than lambs that received colostrum from non-immune ewes. Colostrum from naturally immune vaccinated ewes gave good protection to lambs for up to six weeks but thereafter the effect was variable. The immunity that developed in susceptible ewes after vaccination with activated embryos was not passed on to the lambs via the colostrum.  相似文献   

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The relationship of serum cortisol to immunoglobulin absorption and gut closure in cesarean-derived neonatal lambs was evaluated in two trials. In trial 1, 21 lambs were obtained on d 136 to 138 of gestation, and in trial 2, 17 lambs were obtained on d 140 to 142 of gestation. At birth, lambs were assigned randomly to four treatments: 1) control (CO), 1 ml saline/kg BW every 4 h; 2) a drug to lower cortisol (LC), 5 mg metyrapone/kg BW every 4 h; 3) single-peak cortisol (SP), 10 IU ACTH/kg BW at 0 h; or 4) elevated cortisol (HC), 5 mg cortisol/kg BW every 4 h in trial 1 or 10 IU ACTH/kg BW every 4 h in trial 2. The treatment period was 24 and 48 h after delivery for trial 1 and 2, respectively. Lambs were fed pooled bovine colostrum every 4 h for 48 h after birth at 2 and 3.5% BW for trial 1 and 2, respectively. Compared with CO, HC increased serum cortisol, LC decreased serum cortisol and SP elevated serum cortisol concentrations through at least 8 h for both trials. In trial 1, HC and SP lambs exhibited elevated serum IgG, IgM and IgA concentrations by 20 h compared with CO. However, no difference in serum immunoglobulin concentration was observed at 36 h among CO, HC and SP. Conversely, LC had the lowest immunoglobulin concentration at 36 and 48 h, and precocious closure to immunoglobulin absorption had occurred by 20 h (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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