Development of Rapid Diagnostic Technology for Pig Disease (2) - Rapid detection of PPE in the pig feces - Hyuck-Joo Kim 1 *, Jong-Tae Hong 1 , Byeong-Kee Yu 1 , Giyoung Kim 1 , Suk Kim 2 1 National Academy of Agricultural Science, RDA., Suwon, Korea 2 College of Veterinary medicine, Gyeongsang National University, Jinju, Gyeongnam, Korea Received: May 1 st , 2013; Revised: May 23 th , 2013; Accepted: May 29 th , 2013 Purpose: Porcine proliferative enteropathy (PPE), caused by the obligate intracellular bacterium Lawsonia intracellularis, is a widely distributed disease throughout the world causing substantial economic loss. In order to diagnose PPE rapidly, the rapid kit was developed and tested. Methods: In this study, a rapid kit was developed to screen the PPE rapidly at the pig farm. Also, occult blood test with fecal occult blood (FOB) kit was done for detecting the blood in pig feces which might be the evident of hemorrhagic PPE. For developing the kit, we tested fecal samples of PPE infected pigs diagnosed by polymerase chain reaction (PCR) method. Results: With the developed rapid kit, Lawsonia intracellularis was detected in high density emulsion of ileum. On the other hand, the test result of detecting Lawsonia in feces showed too high non-specific response. In addition, nevertheless the FOB test result showed that blood evident could be founded in pig feces, the diagnosing result was not fit to PCR test result, which shows blood in pig feces could be from not only hemorrhagic PPE but also many reasons. Conclusions: To deal with the PPE effectively, it will be better for farmers to screen the PPE in earlier stage with easy and rapid diagnosing tool on farm. This study found out that the rapid kit could detect the Lawsonia intracellularis and hemoglobin in pig feces. However, the non-specific response to negative samples of PPE was too high to use at a pig farm. Further research is needed for lowering the non-specific response with the rapid kit. Keywords: FOB, Lawsonia, Pig feces, Porcine proliferative enteropathy (PPE), Rapid kit Original Article Journal of Biosystems Engineering J. of Biosystems Eng. 38(2):121-128. (2013. 6) http://dx.doi.org/10.5307/JBE.2013.38.2.121 eISSN : 2234-1862 pISSN : 1738-1266 *Corresponding author: Hyuck Joo Kim Tel: +82-31-290-1867; Fax: +82-31-290-1860 E-mail: agrihj@rda.go.kr Copyright ⓒ 2013 by The Korean Society for Agricultural Machinery This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Introduction The previous study (Kim et al., 2012) explored the combination of antibodies and the diagnosis of the porcine proliferative enteropathy (PPE) using the polymerase chain reaction (PCR) test for developing lateral flow immunoassay. The PPE infection was serious in that 25% of the samples used in the previous study were infected. Accor- ding to Chung (2008), 35.2% of the 155 samples were infected, and 53.2% of pig farms in Gyeong-nam province, Korea were infected. Monitoring possible infectious diseases and preventing the spread of the infections at pig farms are important to reduce the risk of developing diseases. However, conventional lab tests such as PCR test, fluorescence antibody test, and immunohistochem- istry test take several days for the results. For this reason, those tests fail to response effectively and farmers treat the diseases relying on the visual clues. Therefore, development of rapid kit, lateral flow immunoassay, is needed to diagnose the diseases and to prevent the spread of the infection. Impedance biosensor, enzyme-linked immunosorbent assay (ELISA) test kit, and rapid lateral flow immunoassay (rapid kit) were used to detect the infectious bacterials. For detecting the infectious salmonella, a rapid kit was developed (Kim and Lee, 2011). Impedance biosensor