Dilated small and large intestines combined with a severely abnormal demeanor are characteristic of mesenteric torsion in cattle.

To describe the clinical, laboratory, and ultrasonographic findings; treatment; and outcome of cattle with mesenteric torsion (MT). 61 cattle with MT between November 1, 1986, and December 31, 2019. Medical records were retrospectively reviewed. Results were compared for cattle that survived versus did not survive to hospital discharge. All cattle had abnormal demeanor. The most common clinical signs were tachycardia (80.3% [49/61]), tachypnea (65.0% [39/60]), and lower rectal temperature (59.3% [35/59]). Signs of colic occurred in 65.6% (40/61). The most common gastrointestinal findings were an empty or almost empty rectum (100% [59/59]), reduced or absent motility of the small intestines (96.6% [57/59]) or rumen (93.2% [55/59]), positive ballottement and/or percussion and simultaneous auscultation on the right side (91.7% [55/60]), and dilated small (49.2% [29/59]) and large intestines (spiral colon and/or cecum, 44.1% [26/59]) detected during transrectal examination. The most common laboratory findings were acidosis (82.6%, [38/46]) hypermagnesemia (74.5% [35/47]). Ultrasonographic findings included reduced or absent small intestinal motility (86.7% [26/30]) and dilated small intestines (83.8% [31/37]). The spiral colon was dilated in 32.4% (12/37) of the cattle. Eighty-two percent (50/61) of the cattle underwent right flank laparotomy and the MT could be reduced in 34.4% (21/61). Twenty-three percent (14/61) of the cattle survived to hospital discharge, and 77.0% (47/61) were euthanized before hospital discharge. Dilated small and large intestines (spiral colon, cecum) combined with a severely abnormal demeanor and tachycardia are characteristic findings in cows with MT. Immediate surgical treatment is paramount.