4. Necropsy (aborted fetus) 
- Gelatinous infiltration in hypoclerm
- Increasing and turbid of hydrothorax and ascites
- Adhesion of fibrin to abdominal organs


5. Fetal and washing smear 
- Smear and stain : comma like or S-shape spindal
  bacteria by carbol fuchsin solution
                             : by FA method using conjugated
  antibody for bull specimen and gastrointestinal
  content of aborted fetus. Bull specimens are washed,
  centrifuged, and the resuspended sediment is
  filtered through a membrane filter (0.65 µm)
  before examination


6. Bacterial isolation 
Specimen    : semen and preputial washings from bull,
                     contents of abomasum, small intestine
                     and cecum of fetus
Media          : blood agar and selective media for
                     Campylobacter
- Culture     : blood agar should be incubated at 37°C
                     under mixed gas (10% CO₂, 5% O₂ and
                     80-85% N₂) for 2-3 days or use campy
                     pak
                   : thiol medium with rubber stopper is
                     cultivated at 37°C for 3 days for further
                     passage