[Are nasal swabs for swine appropriate for the diagnosis of bacterial pneumonia agents?]. / Sind Nasentupfer beim Schwein zur Diagnostik bakterieller Pneumonie-Erreger geeignet?

Nasal swabs and lungs of 150 pigs with pneumonia were tested by culture at post mortem examination. The isolated agents were Pasteurella multocida (P.m.), P. haemolytica, Bordetella bronchiseptica, Actinobacillus pleuropneumoniae, Staphylococcus aureus, Streptococcus spp. and Escherichia coli. P.m. was most frequently found, and this agent only showed a significant correlation between lungs and nasal swabs. In 80.6% of pigs with P.m. in the lung the agent was detected in the nose, too. Drug resistance patterns of P.m. isolates from lungs and noses of the single animals were identical or similar, also in case of different capsular types. The examination of porcine nasal swabs for bacteria capable of causing pneumonia should be limited to P. multocida. Demonstration of agents in lung material is generally more certain.

[Toxin-producing pasteurellas in a cattle herd]. / Toxinbildende Pasteurellen in einem Rinderbestand.

Besides other agents, indole-negative Pasteurellae, producing dermonecrotic Pasteurella toxin, were isolated from the noses of calves in a herd with enzootic bronchopneumonia. In some blood sera, antitoxin was detected. According to their biochemical activities, isolated strains were classified as P. multocida ssp. septica (ornithine-negative), P. avium (biovar 2), and P. canis (biovar 2). However, in DNA-DNA hybridisation tests there was much coincidence with P. multocida. In experimental calves, pneumonic lesions were produced with one of the isolates as well as with the dermonecrotic toxin. Therefore, indole negative toxinogenic Pasteurellae are considered pneumonia causing agents. They should be taken into account in bacteriological diagnostic and for production of herd specific bacterins.

[Comparison of EBL cells and ELISA in the culture and serological diagnosis of rhinitis atrophicans in swine]. / Vergleich von EBL-Zellen und ELISA in der kulturellen und serologischen Diagnostik der Rhinitis atrophicans des Schweines.

Pasteurella multocida isolates from 271 nasal swabs of pigs were tested in EBL cell culture for toxin production. Mixed bacteria cultures of the same swabs were examined in the P. multocida toxin ELISA K462 (Dakopatts). In the ELISA 114 swabs reacted positive, whereas toxigenic P. multocida were detected by the EBL cell test in 86 swabs. In a neutralization test (SNT) combined with EBL cell culture and with the ELISA 111 sera were examined for P. multocida antitoxin. The toxin had to be more concentrated for the ELISA than for the cell culture; therefore the SNT with EBL cells was more sensitive. Whereas 101 sera had titres of 1:4 or higher in the cell culture, 68 of these sera were positive in the ELISA.

[Detection of neutralizing antibodies against Pasteurella multocida toxin in swine with atrophic rhinitis]. / Nachweis neutralisierender Antikörper gegen das Pasteurella multocida-Toxin bei Schweinen mit Rhinitis atrophicans.

Blood sera of 1171 pigs, not vaccinated against PAR, were tested for antibodies against P. multocida toxin in a neutralization test with EBL cell cultures. 277 sera were from 18 herds with clinical PAR; 104 of them (37.5%) had neutralizing antibody titres from 1:2 to 1:1024. No antitoxin was detected in the sera of 866 pigs in 25 PAR nonsuspicious herds. In one nonsuspicious herd, however, 11 of 28 sera were neutralizing in the 1:2 or 1:4 dilution. 30 sows had been vaccinated with inactivated toxigenic P. multocida and/or with the P. multocida toxoid. 21 of these sows had neutralizing sera with titres between 1:8 and 1:4096. The neutralization test presented can be applied for herd diagnosis of PAR and for demonstration of vaccination effects.

[Pasteurella multocida (type D and A) and atrophic rhinitis of swine--hemagglutination, fimbriae and adhesion in vitro in the nasal mucosa of swine fetuses]. / Pasteurella multocida (Typ D und A) und Rhinitis atrophicans des Schweines--Hämagglutination, Fimbrien sowie Adhäsion in vitro an Nasenschleimhaut von Schweinefeten.

79 strains of P. multocida were investigated, mostly isolated from porcine nasal cavities, and a mannose-resistant hemagglutination with guinea pig and human group 0, but not with porcine erythrocytes was found. Fimbriae as adhesins were demonstrated only on 2 strains. A correlation between capsular type, hemagglutination, fimbriation and toxigenicity on the examined P. multocida strains was not observed. Three strains were investigated for the adherence to the nasal mucosa of neonatal pigs; aggregates shown by scanning electron microscopy indicate colonization; a correlation of adherence with surface proteins and slime production of P. multocida is discussed.

[Atrophic rhinitis of swine--a multifactorial disease?]. / Die Rhinitis atrophicans des Schweines--eine Faktorenkrankheit?

Atrophic rhinitis is caused by toxigenic Pasteurella multocida strains. The infection is supported by Bordetella bronchiseptica and other widespread agents and by non-infectious factors damaging the nasal epithelium. The term "infectious multifactorial disease" means in German, that ubiquitous low-virulent agents cause disease when intensified by non-infectious factors. Atrophic rhinitis does not belong to this group but is an infectious disease, caused by a specific agent and influenced by several factors.