Small intestinal incarceration caused by external herniation can be diagnosed clinically in cattle, but laparotomy is required to confirm internal incarceration.

Objective: To describe the clinical, laboratory and ultrasonographic findings, treatment, and outcome of cattle with small intestinal incarceration (SII) through internal and external hernias.

Methods: The medical records of 85 cattle with SII admitted between January 1, 1987, and December 31, 2019, were retrospectively reviewed. The long-term outcome was determined 2 years after discharge.

Results: 85 cattle had herniation of the small intestine through congenital or acquired openings in mesentery or omentum (internal herniation; n = 60) or the abdominal wall (external herniation; 25). The most common findings were little or no feces in the rectum (77 of 85 [90.6%]), reduced or absent intestinal motility (76 of 85 [89.4%]), and hypocalcemia (36 of 44 [81.8%]). Thirteen (15.3%) cattle died or were euthanized without surgery. Of the remaining 72 (84.7%) cattle that underwent surgery, 42 survived the procedure. Overall, 52 of 85 cattle (61.2%; 95% CI, 50% to 72%) did not survive to hospital discharge and 33 (38.8%; 95% CI, 28% to 50%) were discharged alive. Of these, 11 (33.3%; 6 with and 5 without hernias closed completely) were still productive in their respective herds 2 years later.

Conclusions: The diagnosis of an incarcerated external hernia is usually straightforward, whereas internal SII necessitates laparotomy or postmortem examination for a definitive diagnosis.

Clinical relevance: Internal herniation should be part of the differential diagnosis in cattle with signs of ileus. Immediate surgical treatment is paramount in cattle with SII.