• Korean Journal of Veterinary Service
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• v.41 no.3
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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.

• Journal of Animal Environmental Science
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• v.15 no.2
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• pp.171-182
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• 2009

Conventionally, many pig producers have utilized a continual sow managements system that the matings, farrowings and weanings are done weekly basis. But this transitional method is not able to cut the cycle of diseases and fully apply all-in/all-out system because of the continuous flow of sows and pigs. Conventional weekly management system is currently limiting in small farm to work efficiently both for workers and pigs. Therefore, pig producers have found novel management methods for applying all-in/all-out system, improving pig health, leading to better growth, lowering mortality and reducing medication costs nowadays. Moreover, all-in/all-out pig management system has known as a strategy for improving productivity in swine farm. The batch system is one of the best management methods to adopt all-in/all-out pig management system that prevent spreading diseases in pig and remove cycle of diseases. Batch farrowing system is a concept for providing a group of sows that delivery within a specific farrowing interval and inducing a large enough scale of piglets to fill the weaner facilities. There are different types of batch farrowing system with batch size and interval of farrowing when several factors at the swine farm are considered such as total number of sows, available facilities in the farm, and the efficiency of workforce. Sow managements such as farrowing, weaning and breeding, every 3 weeks rather than weekly, 2 or 5-week interval have advantages for workers and reproductive cycle of sows as well as pig flow. Because there are several pros and cons both in weekly and batch management system, various factors should be considered to apply the most suitable management system in each individual farm. To improve poor swine productivity in Korea compared to ED, batch system for sows will be an alternative choice which is able to prevent high incidence of diseases in swine farm such as PMWS, PRRS, PRDC and PED because all-in/all-out pig management can be also applied automatically by using this management system.