title: Survey of porcine respiratory disease complex-associated pathogens among commercial pig farms in Korea via oral fluid method.
abstract: Oral fluid analysis for herd monitoring is of interest to the commercial pig production in Korea. The aim of this study was to investigate pathogen-positive rates and correlations among eight pathogens associated with porcine respiratory disease complex by analyzing oral fluid samples from 214 pig groups from 56 commercial farms. Samples collected by a rope-chewing method underwent reverse-transcriptase polymerase chain reaction (RT-PCR) or standard polymerase chain reaction (PCR) analysis, depending on the microorganism. Pathogens were divided into virus and bacteria groups. The former consisted of porcine reproductive and respiratory syndrome virus and porcine circovirus type 2 (PCV2), and the latterPasteurella multocida,Haemophilus parasuis,Actinobacillus pleuropneumoniae,Mycoplasma hyopneumoniae(MHP),Mycoplasma hyorhinis, andStreptococcus suis(SS). All pathogens were detected more than once by PCR. Age-based analysis showed the PCR-positive rate increased with increasing age for PCV2 and MHP, whereas SS showed the opposite. Correlations between pathogens were assessed among 36 different pair combinations; only seven pairs showed statistically significant correlations. In conclusion, the oral fluid method could be a feasible way to detect various swine respiratory disease pathogens and, therefore, could complement current monitoring systems for respiratory diseases in the swine industry.
authors: Department of Infectious Diseases, College of Veterinary Medicine, Konkuk University, Seoul 05029, Korea.
authors: Yeotaek
authors: Y
authors: Cheong
authors: Department of Infectious Diseases, College of Veterinary Medicine, Konkuk University, Seoul 05029, Korea.
authors: Changin
authors: C
authors: Oh
authors: Department of Infectious Diseases, College of Veterinary Medicine, Konkuk University, Seoul 05029, Korea.
authors: Kunkyu
authors: K
authors: Lee
authors: Veterinary Epidemiology Division, Animal and Plant Quarantine Agency, Gimcheon 39660, Korea.
authors: Ki-Hyun
authors: KH
authors: Cho
mesh_terms: D000818:Animals; D000072480:Farms / Q000706:statistics & numerical data; D009055:Mouth / Q000821:virology; D019318:Porcine Reproductive and Respiratory Syndrome / Q000453:epidemiology* / Q000821:virology; D019316:Porcine respiratory and reproductive syndrome virus; D056910:Republic of Korea / Q000453:epidemiology; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D011795:Surveys and Questionnaires; D013552:Swine / Q000821:virology
keywords: Korea; oral fluid; pathogens; polymerase chain reaction; porcine respiratory disease complex