Abomasal Ulcers in Cattle
Abomasal ulcers most commonly occur within the first six
weeks of lactation. Metabolic disorders such as ketosis
and displacement of the abomasumalso occur at this
same time. Stress, lymphosarcoma, and diets high in concentrates
have been suggested as predisposing factors.
Four types of abomasal ulcers are: 1) Non-perforating ulcers
involving the mucosa and submucosa have vague clinical signs
including decreased gut motility, partial anorexia, mild
abdominal pain, and stale feces. Traumatic reticuloperitonitis
or indigestion must also be considered with this presentation.
Fecal occult blood tests may be positive. 2) Severe blood
loss can occur with a nonperforating ulcer when the ulcer
erodes into a major gastric blood vessel.
Hemorrhage, anemia, black tarry feces, tachycardia,tachypnea
or shock may result. Abomasal ulcers are the most common
cause of proximalgastrointestinal hemorrhage in cattle.
Another major cause of melena is intussusception. Intussusception
may result in an increased PCV, whereas blood loss by ulceration
will cause a decreased PCV. 3) Perforating ulcers with local
peritonitis are caused by penetration through to the serosal
layers with localized leakage of abomasalcontents. The inflammatory
response is quick to wall off localized peritonitis and
signs may be similar to traumatic reticuloperitonitis. The
prognosis is good with antibiotic therapy, except in pregnant
cows where the gravid uterus interferes with adhesion formation.
4) Perforating ulcers with diffuse peritonitis are a result
of serosal penetration and widespread contamination of the
peritoneum. Signals of rapid septic shock within 24 hours,
including anorexia, tachycardia, bruxism, abdominal
distention and terminal recumbency follow.
Abomasal ulcers may present subclinically, when the ulcer
is small and has not penetrated the gastric mucosa, or with
hemorrhage and peritonitis.
The most useful test for diagnosis of gastrointestinal
bleeding is the fecal occult blood test. Peritonitis
can be confirmed by abdominocentesis. (Localized walled
off peritonitis may give normal results.) Severe blood loss
will result in decreased PCV. Anemic cattle over five years-of-age
should be tested for bovine leukemia (BLV).
At necropsy the lesion in the abomasum is usually small
and involves an abomasal blood vessel. A single bleeding
ulcer in the ventral portion of the abomasum is most commonly
The treatment of abomasal ulcers is limited primarily to
correcting dietary problems, reducing stress and treating
concurrent disease. Antacids, protectants and H:>- blockers
such as cimefidine are ineffective. All affected cattle
should be tested for BLV, as lymphosarcoma can be a cause
of abomasal ulcers.
Epidemiology indicates that all ages are affected. Many
calves sent to slaughter have inapparent erosions and ulcers.
In one study of adult cattle with abomasal ulcers one third
had significant hemorrhage, one third had localized peritonitis
and one third had diffuse peritonitis.
- Patrick Petrowski, Ross
- edited by Lydia