Bordetella bronchiseptica isolations from the nasal cavity of pigs in relation to atrophic rhinitis.

The occurrence of Bordetella bronchiseptica and atrophic rhinitis was studied during a one-year period in four Danish sow herds. In three of the heards, the epidemiological studies revealed a relation between the occurrence of B. bronchiseptica in 3--10-week-old pigs and the presence and severity of atrophic rhinitis at slaughter. In the fourth herd no such relation was found.     

Serologic survey for Bordetella bronchiseptica in Nebraska specific-pathogen-free pigs

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.     

Immunogenicity and safety of an attenuated Bordetella bronchiseptica vaccine in pigs

The immunogenicity and safety of an attenuated Bordetella bronchiseptica vaccine for swine atrophic rhinitis (AR) was evaluated in 22 hysterectomy-produced, colostrum-deprived pigs and 18 conventional pigs. None of 8 pigs inoculated at 7 days of age intranasally with greater than or equal to 3 X 10(5) colony-forming units (CFU) of vaccinal strain/pig and 2 of 5 pigs inoculated at 7 days of age intranasally with 3 X 10(4) CFU of the vaccinal strain/pig developed AR after intranasal challenge exposure with a virulent strain at postinoculation week (PIW) 3. The remaining 3 vaccinated pigs and 4 nonvaccinated pigs developed AR. Thirteen pigs were inoculated intranasally with 3 X 10(6) to 3 X 10(9) CFU of the vaccinal strain at 7 days of age. At PIW 12, the pigs were killed and necropsied. None of the pigs had clinical signs of AR and/or pneumonia. Virulence was studied by transmission of vaccinal strain through 3 serial growing passages on the nasal mucosa of a litter of hysterectomy-produced colostrum-deprived pigs. Inoculum (nasal swab samples from 2 pigs 4 days after inoculation with 10(8) CFU of vaccinal strain at 5 days of age) was inoculated into the nasal cavity of 2 nonvaccinated pigs. This procedure was repeated 3 times. After the 1st passage, the vaccinal strain was recovered on postinoculation day 4, but after postinoculation day 4, the vaccinal strain was not recovered until the end of the 3rd passage. Turbinate atrophy or pneumonia was not recognized in these inoculated pigs. The vaccinal strain provided immunogenicity without ill effects.     

The pathogenesis of turbinate atrophy in pigs caused by Bordetella bronchiseptica

The pathogenicity of 3 strains of Bordetella bronchiseptica designated B58, PV6 and B65 was compared by intranasal infection of gnotobiotic piglets. Strain B58 was a phase 1 isolate that produced haemolysin, an adhesin for calf erythrocytes, adenylate cyclase, mouse lethal factor, dermonecrotic factor and cytotoxin. B65 was a variant of B58 that produced no detectable haemolysin, adhesin or adenylate cyclase and 10-fold smaller amounts than B58 of mouse lethal factor, dermonecrotic factor and cytotoxin. Strain PV6 was a phase 1 isolate that produced only haemolysin, adhesin and adenylate cyclase. After nasal infection of gnotobiotic pigs, 10(3.2)-10(6.2) colony forming units ml-1 (cfu ml-1) of strains B58 and PV6 were cultured from nasal washings during the next 25 days. In contrast, only 10(1.0)-10(2.8) cfu ml-1 of strain B65 were recovered during the same period. Only pigs infected with strain B58 had turbinate atrophy when they were slaughtered 25 days after infection and neutralising antibody to cytotoxin was detected only in these pigs. These results suggested that the cytotoxin, which may be the same as the mouse lethal and dermonecrotic factors, was the cause of turbinate atrophy. They also support the view that the adhesin for calf erythrocytes is required for colonisation of the nasal cavity in vivo.     

Prevalence and risk factors for feline Bordetella bronchiseptica infection.

A cross-sectional survey of a convenience-sample of 740 cats was undertaken to obtain an estimate of the prevalence of Bordetella bronchiseptica infection, and to identify risk factors that might predispose them to the infection. Data on individual cats and household variables, including disease status and animal contacts were obtained by questionnaire. B bronchiseptica was isolated from 82 (11 per cent) of the cats sampled. The prevalence of B bronchiseptica varied with the type of household sampled, being 19.5 per cent in rescue catteries, 9 per cent in breeding catteries, 13.5 per cent in research colonies, and 0 per cent in household pets. On the basis of a univariable analysis, 19 of 29 predictor variables were found to be significantly associated with the isolation of B bronchiseptica, including an association with cats in rescue catteries, and with cats from premises with larger numbers of animals. Separate analysis of the rescue cattery subpopulation showed a highly significant association on multivariable analysis with current respiratory disease, suggesting that different risk factors may operate in this type of environment. In the whole sample there was also strong association with cats from households containing a dog with recent respiratory tract disease. The clinical signs observed in the B bronchiseptica-positive cats included sneezing, ocular and nasal discharges and coughing, although only the association with sneezing was statistically significant. There was no significant association between the isolation of B bronchiseptica and the isolation of respiratory viruses, suggesting that in some circumstances B bronchiseptica may be able to cause disease independently.     

v猪场支气管败血波氏杆菌鼻腔带茵和肺部感染调查分析

对珠三角三个曾发生萎缩性鼻炎,现已临床控制两年以上的大型猪场的健康母猪、乳猪和保育猪鼻腔取样81份,分离支气管败血波氏杆菌,结果21份阳性;对珠三角地区16个猪场送检病猪,取有炎症病变的肺184份,分离波氏杆菌,结果13份阳性。     

A selective medium facilitating the isolation and recognition of Bordetella bronchiseptica in pigs.

A medium was developed that in most instances allowed the isolation from pigs of Bordetella (Alcaligenes) bronchiseptica in pure, or virtually pure, culture from such sites as the nasal cavity, which contains many other bacteria. If not suppressed, some of the latter can inhibit, sometimes completely, the growth of the bordetellae on artificial media. Besides being markedly selective, the new medium is simple to prepare, reasonably cheap and practically noninhibitory to B bronchiseptica. This organism produces a distinctive colony that is easily differentiated on morphological grounds from the few other bacteria (such as Alcaligenes faecalis and Pseudomonas spp) which also grow on this medium. Parallel examination of specimens from the nasal cavities of 219 pigs in the field in southern England confirmed that this medium was better than hitherto recommended for the detection of B bronchiseptica. This was particularly true when the organism occurred in small numbers only and/or when bacteria little affected by the inhibitors in the previously recommended media were present in the nasal flora.     

猪支气管败血波氏杆菌PCR诊断方法的建立及应用

根据支气管败血波氏杆菌（Bordetella bronchiseptica）鞭毛蛋白基因的上游序列设计了1对引物flal和fla2，扩增出大小为237bp的目的基因片段，建立了快速检测支气管败血波氏杆菌的PCR方法。特异性和敏感性试验表明，该方法对大肠埃希氏菌、金黄色葡萄球菌和D型多杀性巴氏杆菌均无交叉性反应；最低能够检出112．5pg的模板DNA。用该PCR法检测了从延边州采集的48份表现不同临床症状的猪鼻黏液；结果，检出支气管败血波氏杆菌阳性42例，阳性率为87．5％。同时与传统的细菌检查法、微量凝集法进行了比较；结果显示，该PCR法的检出率是细菌检查法的5．25倍，是微量凝集法的1．75倍。     

Polymorphism of pertactin gene repeat regions in Bordetella bronchiseptica isolates from pigs

Bordetella bronchiseptica pertactin (prn) is an outer membrane protein which has been implicated as both an adhesin and a protective antigen that induces immunity against atrophic rhinitis in pigs. Previous studies demonstrated extensive heterogeneity of the prn sequence within two distinct regions of amino acid repeats for B. bronchiseptica isolated from the United States and Europe. By deducing the amino acid sequences of the repeat regions of the prn gene from recent isolates from Korea, two region 1 variants and five region 2 variants were identified. Five pertactin types were distinguished based on combinations of variants of both regions. Interestingly, none of the field isolates have the same pertactin type as the B. bronchiseptica P4 strain widely used to vaccinate pigs.     

Interactions between Bordetella bronchiseptica and toxigenic Pasteurella multocida in atrophic rhinitis of pigs

Three strains of Bordetella bronchiseptica were compared for their ability to assist colonisation of the nasal cavity of gnotobiotic pigs by toxigenic Pasteurella multocida. Toxigenic P multocida (counted in nasal washings) colonised the cavity in large numbers in pigs previously infected with a cytotoxic phase I strain of B bronchiseptica (B58), whereas it colonised only in small numbers in those previously infected with B65, a phenotypic phase III variant of B58. Toxigenic P multocida colonised pigs infected with a non-cytotoxic phase I strain of B bronchiseptica (PV6) in fewer numbers than were seen in pigs infected with the cytotoxic phase I strain but in greater numbers than in pigs infected with the phase III strain. The turbinates of pigs infected with the cytotoxic phase I strain of B bronchiseptica and toxigenic P multocida were most severely affected and those in pigs infected with the non-cytotoxic phase I strain and toxigenic P multocida were moderately reduced in size. The turbinates of pigs infected with the phase III strain and toxigenic P multocida were slightly reduced in size except for one piglet whose turbinates were severely affected. Pigs infected with the non-cytotoxic phase I strain of B bronchiseptica alone showed no signs of atrophy and their turbinates were used to calculate reductions (per cent) in those infected with P multocida. The reduction (per cent) in size of turbinates and total numbers of P multocida isolated from the nasal washings of each pig were linearly related.(ABSTRACT TRUNCATED AT 250 WORDS)