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1.
Natural transmission of atrophic rhinitis from pigs from a herd with an endemic atrophic rhinitis problem to pigs from a herd free of atrophic rhinitis was demonstrated. Six replicates each with five pigs from the endemic atrophic rhinitis herd (Group A) and five pigs from the atrophic rhinitis-free herd (Group B) were housed together from 5 wk of age, with each replicate kept in isolation rooms maintained at optimal and controlled environmental conditions. Three replicates each with six pigs/room from the atrophic rhinitis-free herd (Group C), served as nonexposed controls. Group C pigs remained healthy and had no turbinate atrophy at either 10 or 17 wk of study (atrophic rhinitis score = 0 on a 0 to 3 scale). Group A pigs had a mean atrophic rhinitis score of 1.85 +/- 0.84, and group B pigs developed atrophic rhinitis to a mean score of 1.57 +/- 0.70. The isolation rate and quantity of Pasteurella multocida found on nasal swabs was directly related to lesions while those for Bordetella bronchiseptica were inversely related to turbinate atrophy. Of the various types of P. multocida evaluated, nontoxigenic type A and toxigenic type D were both directly related to atrophic rhinitis while nontoxigenic type D strains were not. No toxigenic type A P. multocida strains were isolated.  相似文献   

2.
Blood was collected the day before slaughter from pigs fed fine, medium or coarse ground grain and examined in accordance with Tables 1–3. Of the 15 pigs (group 1) on the finest meal all except one developed parakeratotic or erosive changes (Figs. 1–5) in the pars oesophagea of the stomach. In group 2 (medium ground) the corresponding number was seven out of 18. No pathological alterations could be detected in the stomach of the pigs on coarse grain.Statistically significant or almost significant differences were obtained between the groups for hemoglobin, hematocrit, number of erythrocytes, urea-N and pepsinogen. A much wider range was observed in the γ-globulins of the group on fine grain than in the other two groups. The differences in proteins were, however, not significant. To see whether the observed differences between the groups were related to the gastric pathological alterations or to the feed, a comparison was made between pigs with and without pathological changes (Table 3). There were still significant, though smaller, differences in the hemoglobin and hematocrit values. A higher level of significance was only obtained for pepsinogen.  相似文献   

3.
The acute phase reaction, in association with progressive atrophic rhinitis (AR), was monitored for 3 wk using serum haptoglobin (HPT) quantification in thirty-six, 15 kg swine after intranasal challenge with varying doses of Pasteurella multocida type D (toxigenic strain) and Bordetella bronchiseptica. The challenge doses were administered alone or in combination with pigs divided into 9 isolated treatment groups. Increasing doses of B. bronchiseptica were associated with lower serum HPT (P < 0.05), whereas increasing doses of P. multocida tended to increase serum HPT (0.05 < P < 0.10). Significant and positive correlation of mean HPT and AR score was found in these pigs; increased AR scores were associated with elevated mean HPT concentration (r = 0.41, P < 0.01). A significant interaction between P. multocida and B. bronchiseptica dose indicated that increasing the dose of B. bronchiseptica, for a fixed P. multocida dose, was associated with less AR (P < 0.05). The AR scores were greater in pigs given P. multocida, than B. bronchiseptica alone. These results indicate that a complex interaction between Pasteurella multocida and Bordetella bronchiseptica causes progressive atrophic rhinitis and alters serum HPT concentration in swine.  相似文献   

4.
The frequency of Bordetella bronchiseptica infection in Nebraska specific-pathogen-free (SPF) pigs was determined by serologic and bacteriologic cultural analysis. Serum samples from non-SPF herds were tested for comparison. A total of 1,282 of 1,397 (92%) of the SPF pigs tested had antibody to B bronchiseptica; 37 of 220 (17%) were culture-positive, and 67 of 4125 (1.6%) were considered suspicious for atrophic rhinitis during slaughter inspection. A higher percentage of the non-SPF pigs had titers to B bronchiseptica (642 of 659 pigs or 97% of the pigs tested). There was no relationship between the B bronchiseptica antibody titer, the isolation of B bronchiseptica, or the frequency of gross lesions of atrophic rhinitis from pigs within the herd. The serum agglutination test may be a more reliable procedure for determining the herd prevalence of B bronchiseptica than isolation of the organism by cultural methods.  相似文献   

5.
In three different fattener herds pigs primarily AR infected as baby piglets were mixed in the fattening units with healthy pigs at an age of 11--13 weeks. Snout alterations were registered on cut snouts at a slaughter weight of about 70 kg. Severe AR was registered in the groups of primarily infected pigs (Tables I--III). The incidence of snout alterations was lower in the groups of pigs infected at an age of 11--13 weeks, but was much higher than in the groups of healthy control pigs or in the normal pig population in the region (Table IV). The results indicate that pigs infected at a rather late age in the fattening units can develop severe atrophic rhinitis.  相似文献   

6.
本试验对吉林部分地区规模化猪场进行猪传染性萎缩性鼻炎病原学调查。采集吉林不同地区6个规模化猪场阳性猪鼻腔黏液148份,进行病原菌的分离与鉴定。结果表明,148头猪中有84头被支气管败血波氏杆菌感染,占56.76%;被产毒素多杀巴氏杆菌感染53头,占35.81%;混合感染的11头,占7.43%。结果提示,吉林地区规模化猪场中猪传染性萎缩性鼻炎多以支气管败血波氏杆菌感染为主,混合感染程度轻微。  相似文献   

7.
Experimental Atrophic Rhinitis in Gnotobiotic Pigs   总被引：5，自引：0，他引：5       下载免费PDF全文
Twenty-nine caesarian derived colostrum deprived germfree pigs were reared in isolators in groups of three to four per isolator. At seven days of age each group was inoculated intranasally with one of four strains of Bordetella bronchiseptica (designated B, J, L and 55B), or Pseudomonas aeruginosa or a mucoid strain of Escherichia coli, all previously isolated from nasal mucus of pigs affected with clinical atrophic rhinitis. Another group was inoculated simultaneously with B. bronchiseptica B and Pasteurella multocida. The animals were observed for clinical signs of atrophic rhinitis and monitored bacteriologically at weekly intervals for seven weeks. Then they were bled for serology and killed and their respiratory organs examined for gross and histopathological lesions.

All of the pigs inoculated with the Bordetellae had inflammation of the nasal mucosa and developed positive serum antibody titers against all four of the Bordetella strains used in this study. Strain J caused sneezing and turbinate atrophy in three of four pigs. One of the three pigs inoculated with strain L died in ten days from bronchopneumonia and pericarditis and had turbinate atrophy. Strains B and B55 caused no turbinate atrophy, but two out of three pigs inoculated with both B. bronchiseptica B and P. multocida had turbinate atrophy. No nasal lesions were observed in the pigs inoculated with E. coli or P. aeruginosa or in the noninoculated germfree controls.

The results indicate a variation in the ability of different strains of B. bronchiseptica to cause turbinate atrophy in pigs and demonstrate that nasal infections by these organisms stimulate serum antibody response. Presence of P. multocida appears to increase the severity of the lesions. As the E. coli and Pseudomonas failed to produce atrophic rhinitis, they are probably of no significance as primary etiological agents in the atrophic rhinitis syndrome in swine.

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8.
Mild or subclinical respiratory infections caused by Bordetella bronchiseptica are widespread in pigs despite multiple control efforts. Infection with virulent B. bronchiseptica strains is a common risk factor in the establishment of toxin-producing strains of Pasteurella multocida in the nasal cavity of pigs leading to the disease, atrophic rhinitis (AR). This study was designed to explore the possibility of expressing a protective epitope of P. multocida toxin (PMT) in B. bronchiseptica to create single-component mucosal vaccine to control atrophic rhinitis in pigs. To achieve this, a P. multocida toxin fragment (PMTCE), that was non-toxic and protective against lethal challenge in mice, was cloned into a broad-host-range plasmid, PBBR1MCS2, and introduced into B. bronchiseptica by electroporation. The Pasteurella gene construct was placed under the regulatory control of a promoter region that was separately isolated from B. bronchiseptica and appears to be part of the heat shock protein gene family. B. bronchiseptica harboring the plasmid under antibiotic selection expressed the 80kDa PMTCE as determined by PAGE and Western blot with a PMT-specific monoclonal antibody. When introduced into the respiratory tracts of mice, B. bronchiseptica harboring the plasmid construct was reisolated in declining numbers for 72h post-inoculation. Antibody responses (IgM, IgA and IgG) to B. bronchiseptica were detected in serum and respiratory lavage, but PMTCE-specific antibodies were not detected. While further refinements of PMT expression in B. bronchiseptica are necessary, this study provides a basis for the development of a single-component, live-attenuated vaccine against atrophic rhinitis.  相似文献   

9.
Crude dermonecrotic toxins (DNT) were prepared from Pasteurella multocida (P.m.) type D and type A strains isolated from pigs with atrophic rhinitis. Rabbits were immunized with the DNT of P.m. type D. This serum neutralized the DNT of P.m. type A to the same degree as the homologous one both in vitro (cytopathogenicity for tissue culture cells) and in vivo (mouse lethality and dermonecrotic activity in guinea pig).  相似文献   

10.
The influence of some diseases (lesions at slaughter) on daily weight gain and the relation between some mainly non-environmental factors and diseases, weight gain and carcass quality were studied in 12 herds running an all in/all out fattener production. The material consisted of 9800 baconers slaughtered in the period 1975–1977. The piglets were purchased when about 10 weeks old. The number of batches was 60.The investigation showed that 6 of the 12 diseases included in the analyses had a statistically significant influence on daily weight gain: pyaemia, atrophic rhinitis, severe and moderate pneumonia, tail lesion and scabies. The effect varied from a calculated reduction of 60 g in daily weight gain in pigs having atrophic rhinitis to a positive influence of 5 g/day in animals with recorded scabies lesions.It was also found that an increase in weight of marketing piglets would reduce the risk of contracting many diseases and accordingly increase the frequency of healthy animals. It also seemed possible to increase the frequencies of healthy animals by buying quality piglets. Further, quality piglets had a positive relation to weight gain and best paid carcasses (highest quality). Analyses of flock based antiparasitic treatment were inconclusive with regard to weight gain, parasitic hepatitis and scabies.  相似文献   

11.
Forty-five day-old broiler chicks were equally divided into 3 groups, 2 being fed 2,4-D and 2,4,5-T, respectively, from the fifth day of life for up to 7 months, at 1,000 p.p.m. in the drinking water, and the third serving as a control. From 8 weeks of age 2 of the control animals were fed 2,4-D at the same rate for 7 months.Seven of the treated animals died, or were killed in a moribund state, during the experiment (Table 1), the survivors showing only slight signs of poisoning such as reduced mobility and food and water intakes.Animals were sacrificed after varying time intervals (Table 1). The tissue distribution patterns of 2,4-D and 2,4,5-T, as determined in selected tissues of a few of the animals (Table 2), were similar to that observed earlier with 2,4-D.Both compounds produced qualitatively similar morphological effects, although the action of 2,4,5-T apparently was somewhat more intense.The predominant necropsy finding was kidney enlargement (Table 1) due to hypertrophy of the proximal convoluted tubular epithelium (Fig. 1).Electron-microscopically, increased numbers of mitochondria were demonstrated in the tubular cells, with variations in mitochondrial size, shape and structure (Figs. 4–7). The number of micro-bodies was also definitely increased (Figs. 2 and 4). In the nuclei nuclear bodies were observed (Figs. 2 and 3).The significance of the findings is discussed.  相似文献   

12.
To facilitate the control of progressive atrophic rhinitis (PAR) of swine caused by toxigenic Pasteurella multocida, an enzyme-linked immunosorbent assay (ELISA) and a serum neutralization test (NT) have recently been developed to detect antibodies against the P. multocida dermonecrotic toxin (PmDNT). However, the NT is a cumbersome and time-consuming technique. To overcome these drawbacks, we developed an indirect ELISA, using recombinant PmDNT expressed in Escherichia coli, for the detection of antibodies to PmDNT in serum samples from pigs. The practical usefulness of this ELISA was compared with the NT using serum samples obtained from experimentally infected and naturally infected pigs. In the pigs experimentally inoculated with vaccine including PmDNT toxoid, the ELISA and neutralization antibodies were detected at almost the same time, and a good correlation was demonstrated between both tests (P<0.01, R(2)=0.807). Therefore, the ELISA can be used to evaluate the immune reaction of pigs after vaccination with P. multocida toxoid. In a survey conducted on a field herd with a history of clinical AR, the seropositivity by ELISA in pigs of age 4.5-6 months was increased even though the NT was negative, and the correlation was low between the results obtained with the two tests (P<0.01, R(2)=0.38). Therefore, the results indicated that this ELISA might be a useful alternative to the NT currently used to detect the antibody to PmDNT after vaccination or infection with P. multocida.  相似文献   

13.
猪萎缩鼻炎研究进展   总被引：4，自引：2，他引：2  
猪萎缩性鼻炎是猪的一种重要的呼吸系统疾病 ,该病给养猪业造成了重大的经济损失 ,其病原是支气管败血波氏杆菌和产毒素多杀性巴氏杆菌。支气管败血波氏杆菌引起非进行性萎缩性鼻炎 ,而产毒素多杀性巴氏杆菌引起进行性萎缩性鼻炎。二者在致病机理、临床症状、病理变化、流行病学和控制方法等方面存在很大差异。鉴于环境因素和病原因子在此病发生过程中均起一定作用 ,对本病的控制应是多种措施的综合。  相似文献   

14.
The efficacy of a Bordetella bronchiseptica bacterin was evaluated in 2 commercial swine herds affected with mild and severe enzootic atrophic rhinitis (AR). In the 1st herd study, (mild AR), the degree of clinical AR, nasal turbinate evaluation, blood serum titer to B bronchiseptica antigen, and adjusted days from birth to 100 kg were determined for individual pigs. Bacterin inoculation reduced the incidence and severity of gross turbinate atrophy 57% and reduced clinical AR over 93%. Inoculated swine had an average blood serum-agglutinating titer greater than 1:2,793 and noninoculated (control) swine had an average titer of 1:112. Increased serum titer significantly (P less than 0.05) correlated with decreased degree of nasal turbinate atrophy. Inoculated and control pigs reached 100 kg in an average of 171 and 178 days after birth, respectively. In the 2nd study (severe enzootic AR), inoculated and control pigs were individually evaluated for clinical AR and total average daily weight gain. Inoculation reduced clinical AR over 90%. The total average daily gain for the inoculated and control pits was 435.84 g and 340.50 g, respectively. Inoculated pigs and control pigs reached 100-kg market weight in 184 and 238 days, respectively.  相似文献   

15.
The development of circulating antibodies for H. parahaemolyticus was studied in experimentally infected SPF pigs and in-contact SPF pigs. Blood serum titers were determined by a modified complement fixation test with normal SPF swine serum as a source of supplementary complement factor, and by an indirect haemagglutination test.CF and IHA titers became positive within the first 2 weeks following exposure to H. parahaemolyticus, and reached peak values after 2 to 7 weeks (Figs. 1 to 3). The exposed pigs proved immune, in that they showed no clinical symptoms on challenge after resp. 6, 9 and 11 weeks.While distinct titers were thus obtained with both tests in SPF swine experimentally exposed to H. parahaemolyticus, the CF test proved more specific than the IHA test when the 2 tests were compared in a field outbreak of polyserositis (Glässers disease) caused by H. parasuis. The CF test would therefore seem to be preferable to the IHA test in field diagnostic work (Table 1).A noticeable finding was that challenge did not elicit an anamnestic antibody response in any of the immune pigs (Figs. 1 to 3). This fact together with negative bacteriological findings in the animals in question would seem to suggest that the challenge dose was unable to establish a permanent infection in the respiratory tract of the immune pigs.  相似文献   

16.
Although no clinical signs of atrophic rhinitis (AR) were recognized in 2- and 5-week-old pigs, approximately 60% of 2- to 6-month-old pigs showed clinical signs of AR in an affected pig farm. None of the pigs had normal turbinate at slaughter. Bordetella bronchiseptica was not isolated from any of the pigs before onset and incipient stage of the outbreak (2-week to 2-month-old). Pasteurella multocida of capsular type D was not isolated from any of those pigs. However, toxigenic P. multocida of capsular type A was isolated from a number of the pigs immediately before onset and incipient stage of the outbreak. Thirty-six-day-old primary specific-pathogen-free pigs were inoculated intranasally with a toxigenic type A P. multocida isolated from a 5-week-old pig. Severe nasal turbinate atrophy was observed in those pigs which were necropsied at 3 weeks post-inoculation. This is the first report on outbreak of severe nasal turbinate atrophy induced by toxigenic type A P. multocida in Japan.  相似文献   

17.
An experiment was conducted to test the hypothesis that the requirement for Ca expressed as a ratio between standardized total tract digestible (STTD) Ca and STTD P obtained in short-term experiments may be applied to pigs fed diets without or with microbial phytase from 11 to 130 kg. In a 5-phase program, 160 pigs (body weight: 11.2 ± 1.8 kg) were randomly allotted to 32 pens and 4 corn–soybean meal-based diets in a 2 × 2 factorial design with 2 diet formulation principles (total Ca or STTD Ca), and 2 phytase inclusion levels (0 or 500 units/kg of feed) assuming phytase released 0.11% STTD P and 0.16% total Ca. The STTD Ca:STTD P ratios were 1.40:1, 1.35:1, 1.25:1, 1.18:1, and 1.10:1 for phases 1 to 5, and STTD P was at the requirement. Weights of pigs and feed left in feeders were recorded at the end of each phase. At the conclusion of phase 1 (day 24), 1 pig per pen was euthanized and a blood sample and the right femur were collected. At the end of phases 2 to 5, a blood sample was collected from the same pig in each pen. At the conclusion of the experiment (day 126), the right femur of 1 pig per pen was collected and carcass characteristics from this pig were measured. No interactions were observed between diet formulation principle and phytase inclusion for growth performance in any phase and no differences among treatments were observed for overall growth performance. Plasma Ca and P and bone ash at the end of phase 1 were also not influenced by dietary treatments. However, on day 126, pigs fed nonphytase diets formulated based on total Ca had greater bone ash than pigs fed STTD Ca-based diets, but if phytase was used, no differences were observed between the 2 formulation principles (interaction P < 0.05). At the end of phases 2 and 3, pigs fed diets without phytase had greater (P < 0.05) plasma P than pigs fed diets with phytase, but no differences were observed at the end of phases 4 and 5. A negative quadratic effect (P < 0.05) of phase (2 to 5) on the concentration of plasma Ca was observed, whereas plasma P increased (quadratic; P < 0.05) from phases 2 to 5. However, there was no interaction or effect of diet formulation principle or phytase inclusion on any carcass characteristics measured. In conclusion, STTD Ca to STTD P ratios can be used in diet formulation for growing-finishing pigs without affecting growth performance or carcass characteristics and phytase inclusion ameliorates bone resorption caused by low dietary Ca and P.  相似文献   

18.
Summary Sera from 683 pigs of 41 swine herds with clinical atrophic rhinitis (A R), from 477 pigs of 37 herds with no A R history, from 267 breeding sows and breeding boars for slaughtering, from 22 boars at an artifical insemination centre, and from 103 SPF pigs were tested for the presence of antibodies to porcine cytomegalo virus (PCMV). The herds examined were spread all over the Netherlands. For the presence of antibodies to PCM V the indirect fluorescence antibody test was used. To obtain the antigen, the PCMV had been grown in pig lung macrophage cultures in Petri dishes for 10-12 days. These macrophages were dropped into the wells of slides. The serum dilution 1:20 of all the 103 sera from SPF pigs were negative, but 93 per cent of the other sera were positive. No marked differences were found between swine herds with clinical atrophic rhinitis and herds with no A R history. The FA titres in both types of herds seem to be at a comparable level.  相似文献   

19.
Air quality, respiratory disease, and growth rate were followed in four different farrowing and nursery systems. Ammonia levels varied with ambient air temperature, but were within normally accepted levels (25 ppm). These levels of ammonia did not appear to affect the health or performance of the pigs raised in these units. Hydrogen sulfide levels were consistently low. Counts of bacterial colony forming particles (BCFP) varied and the organisms identified were predominantly micrococci. Bordetella bronchiseptica was isolated from nasal cavities of pigs from 3 out of 4 farms. Three of the farms did not have evidence of atrophic rhinitis; pigs farrowed in the last quarter of the test year on one farm from which B. bronchiseptica was isolated developed lesions of atrophic rhinitis. The B. bronchiseptica isolates from the 3 farms were virulent for gnotobiotic piglets. Groups of pigs for slaughter inspection from one farm had lungs with 11–28% pneumonic lesions; these lesions were not typical of mycoplasmal pneumonia.  相似文献   

20.
Atrophic rhinitis in goats in Norway   总被引：1，自引：0，他引：1  
The spontaneous occurrence of atrophic rhinitis in 12 of 49 goat herds in one area of Norway is described. The clinical signs included nose bleeding, nasal discharge, sneezing and tender noses. Pathologically, the macroscopic and histological findings resembled those found in pigs with atrophic rhinitis. Bacteriological investigation of nasal swabs in five of the herds revealed toxigenic strains of Pasteurella multocida in three of them. In four of the herds the clinical signs were seen in two or more consecutive years. No specific source of the infection was discovered. Atrophic rhinitis was induced experimentally in kids by the nasal inoculation of toxigenic strains of P multocida and atrophic rhinitis toxin.  相似文献   

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