Groups of wasting, cachexia and retard growth piglets were selected from farrowing house at the age of 14-25 days together with the groups of 6-8 weeks old pigs at nursery barn from 10 selected farms which history of PMWS and high loss related. One case control farm, free from 3 target viruses was reserved as control. From each individual pig serum and target organs namely : tonsil, lung, lymph nodes in upper respiratory system, GI tract system, mesenteric lymph nodes and superficial inguinal lymph nodes, spleen and kidney (8 organs)were collected from piglets of those 2 groups per farm. Pool sera and pool organs were tested by PCR technique for 3 viruses: porcine circo virus type2 (PCV2), porcine reproductive and respiratory syndrome (PRRS) and classical swine fever (CSF). The PCR results from 10 farms, suckling piglet group, pool sera were negative to PCV2, positive to PRRS 20% and positive to CSF 10%, pool organs were positive to PCV2 10%, positive to PRRS 20% and positive to CSF 10%. From nursery pig group, pool sera were PCV2 positive 50%, PRRS positive 80% and CSF positive 30%, pool organs were PCV2 positive 50%, PRRS positive 70% and CSF positive 40% respectively. From 10 farms, 8 organs from both groups were tested only PCV2 by PCR. PCV2 was found positive 58.33% of tested organs in six PCV2 positive farms out of 10 farms. Frequency of organs to found PCV2-positive samples were mostly in tonsil and kidney (50% and 41.66%). Whereas lymph nodes group were found lower in this study, lymph nodes in abdominal cavity were found 25%, upper respiratory lymph nodes 16.66%, mesenteric lymph nodes 16.66%, superficial inguinal lymph nodes 12.50% and lung 4.17% while spleen was not found.
