MONITORING EXPERIMENTAL SWINE-DYSENTERY - RECTAL SWAB BLOOD-TEST AND SERPULINA (TREPONEMA) HYODYSENTERIAE DETECTION

In two experiments, ten postweaning piglets were inoculated intragastr ically with cultures of Serpulina (Treponema) hyodysenteriae strain B2 04 and were individually monitored for swine dysentery. Eight control animals received sterile culture medium. Between the day of inoculatio n and 35 days later, rectal swab samples were assayed for fecal blood by means of a commercial test kit and for S. hyodysenteriae cells by d irect (phase contrast) microscopy and selective culture methods. Optim al detection of S. hyodysenteriae required both microscopy and culturi ng. Of 41 rectal swab samples positive for fecal blood, 38 (93%) were positive by direct microscopy, by selective culture, or by both techni ques. Of 118 samples negative for fecal blood, 115 (97%) were negative by direct microscopy, by selective culture, or by both techniques. Sw ab samples from control swine were negative for fecal blood. The fecal blood test was a convenient and reliable method for objectively monit oring individual animals with experimental swine dysentery. The occult blood test used in these studies might be generally useful for veteri nary surgeons to monitor and diagnose swine intestinal disorders in wh ich fecal blood is produced.