• 한국동물위생학회지
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• 제41권3호
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• pp.203-210
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• 2018

Pasteurella multocida is an opportunistic organism that plays a significant role in porcine respiratory disease complex (PRDC). In the current study, we provide nationwide information of P. multocida isolates from pneumonic lungs of slaughter pigs by determining their prevalence, subspecies, biovars, capsular types, virulence-associated genes, and minimum inhibitory concentrations. P. multocida was the second most frequently confirmed (19.2%) bacterial pathogen and most of the isolates (88.9%) showed simultaneous infection with other respiratory pathogens, especially Mycoplasma hyopneumoniae (63.3%, P<0.001) and porcine circovirus type 2 (53.3%, P=0.0205). Of 42 isolates investigated, 41 (97.6%) were identified as P. multocida subspecies multocida, and only one isolate was identified as subspecies septica (biovar 5). All the isolates were capsular type A and the most prevalent biovar was biovar 3 (40.5%), followed by biovar 2 (31.0%). Comparing virulence-associated genes and biovars, all biovar 2 isolates exhibited $hgbB^-pfhA^+$ (P<0.001); all biovar 3 (P=0.0002) and biovar 13 (P=0.0063) isolates presented $hgbB^+pfhA^-$. Additionally, all biovar 2 (P=0.0037) isolates and most of biovar 3 (P=0.0265) isolates harbored tadD. P. multocida showed the highest resistance levels to oxytetracycline (73.8%), followed by florfenicol (11.9%). Continuous monitoring is required for surveillance of the antimicrobial resistance and new emerging strains of P. multocida in slaughter lines.

• 한국동물위생학회지
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• 제24권1호
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• pp.1-8
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• 2001

This study was carried out to investigate and analyze the gross lesions of lungs in slaughtered pigs. Pigs were collected from the areas of Kyounggj, Chungbuk, Chungnam and Kangwon provinces from November to December 1999. One hundred-eleven pigs(17.4%) had lung lesions with various degrees among 639 pigs tested. By the standard scoring system, mean score of the lung lesion was 25.6+13.2. Regional prevalence of lung lesions were 23.5%(8/34)) in Kangwon, 17.3%(61/352) in Kyunggi, 15.7%(32/204) in Chungnam and 20.4%(10/49) in Chungbuk. Mean number of pulmonary lesions per pig were 2.87. Most frequent region with pulmonary lesions was right cranial lobe(30.1%) and the decreasing prevalence rates were followed by 23.8% in right middle lobe, 21.05 in right accessory lobe, 15.0% in left cranial lobe, and 5.0% in left middle and accessory lobe(5.0%) and also there was the same prevalent tendency on pulmonary lesions in each lobes of 111 pigs with gross lesion. Isolation rate of bacteria from the affected lungs was 72.1% and main pathogen was Pasteurella multocida. Gross and histological examination of pulmonary lesions in some pigs suggested that there were no marked changes regarded as the correlation with specific diseases except fibropurulent bronchopneumonia which was suspective of some respiratory bacteria including Pasteurella multocida and peribronchiolar lymphoid hyperplasia in varying degrees which was strongly associated with mycoplasmal infection. Consequently, the results in the study were suggested that there was consistently exposed against many causative factors including bacteria in the considerable number of pig herds rearing in the middle area in Korea.