This study involved 60 cows aged 1.9 to 13 years (mean 4.8 +/- 2.3 years) with type-3 abomasal ulcer. The most common clinical signs were, in decreasing order of frequency, partial or complete anorexia (98%), obtunded demeanour (95%), decreased skin surface temperature (78 0 /o), congested scleral vessels (73 0 /0), abdominal guarding (61%), tachypnoea (58%), fever (58%) and tachycardia (55%). One or more concomitant disorders were diagnosed in 86% of the cows. The most common abnormal laboratory findings were hypokalaemia (75%), shortened glutaraldehyde test time (46%) and hyperfi-brinogenaemia (43%). The diagnosis of type-3 abomasal ulcer was made in all cows during laparotomy and/or at postmortem examination. Forty-eight (80%) cows were euthanased immediately after the initial examination, during laparotomy or after unsuccessful treatment. Twelve (20%) cows were treated with a solution of sodium chloride and glucose administered via an indwelling jugular catheter, antibiotics, metamizole or flunixin, and discharged from the clinic. Ten cows were still in production two years later.