PARAINTESTINAL MESENTERIC ABSCESS AND CHRONIC PERITONITIS IN A BULL

A 2-year-old bull was examined because of intermittent anorexia, signs of mild colic, and weight loss of 3 weeks' duration. A tympanitic res onance (ping) could be heard during simultaneous auscultation and perc ussion of the right paralumbar fossa, and a mass could be felt in the right dorsal quadrant of the abdominal cavity during palpation per rec tum. Right flank laparotomy was performed, and intraoperative ultrason ography and ultrasound-guided fine-needle aspiration were used to dete rmine that the mass was an abscess. However, the abscess could not be removed or drained into the colon because of extensive adhesions to ot her organs. Because the owner refused to pursue continued medical trea tment, the bull was euthanatized. At necropsy; the abcess was found to be connected to a caudal mesenteric lymph node through a fistula. His tologic evaluation of the lymph node revealed hyperplastic lymphadenit is, and an alpha-hemolytic streptococcus was recovered from the absces s fluid. The most likely possibility for the findings in this bull wer e that the lymphadenitis was of hematogenous origin and that the absce ss developed as a direct extension of the infectious process, similar to development of mesenteric abscesses in horses with chronic streptoc occal infection (ie, strangles).