육용종계 가금티프스 발생에 따른 검사방법 개선 방안

Suggestions for a better inspection method according to the occurrence of fowl typhoid in broiler breeders

Pullorum disease and fowl typhoid are septicemic avian diseases transmitting through egg by transovarian infections. A series of tests has been performing in breeding flocks of chickens and test plans for proper inspection have been modified by government veterinary institute to control of such diseases. To improve inspection plans, different test methods were compared using fowl typhoid positive samples from a poultry farm located in Jeonbuk state in 2012. Based on first inspection, 11 samples among total 200 samples were positive by rapid slide agglutination (RSA) test and 7 samples among RSA positive samples were finally diagnosed as Salmonella Gallinarum infection by ELISA, bacterial isolation, PCR, and histopathologic examination. In the second inspection, 20 samples among total 100 samples were positive by RSA test. Among RSA positive ones, 19 samples were positive by ELISA, S. Gallinarm were successfully isolated in 3 samples, and 16 samples were positive by PCR in the cecal tonsils where were not successful for bacterial isolation. Based on histopathologic examination, severe inflammation in the 13 cecal tonsils and infiltration of lymphocytes and heterophils in the 11 livers were observed. Therefore, we suggest that bacterial isolation, PCR, and histopathologic examination methods in the third inspection need to be further used in various tissues for correct diagnosis and for final eradication of pullorum disease and fowl typhoid in breeding flocks of chickens.