Abomasal Volvulus in Cows: Life-Threatening Twisted Stomach Emergency

Abomasal volvulus is a severe form of abomasal displacement where the abomasum, the cow's true stomach, moves to the right side and twists. That twist can block outflow, trap large amounts of fluid and gas, and reduce blood flow to the stomach wall. When blood supply is compromised, the tissue can become ischemic and the cow can decline very quickly.

This is not the same as a mild digestive upset. Cows with abomasal volvulus are usually much sicker than cows with a simple left displaced abomasum. They often show complete loss of appetite, rapid dehydration, falling milk production, and signs of circulatory compromise.

The problem is most common in high-producing dairy cows, especially in the period around calving. In many cases, a right displaced abomasum appears to come first, then progresses to volvulus. Early veterinary care matters because the time from diagnosis to treatment strongly affects outcome.

Abomasal volvulus is considered multifactorial. The main underlying problem is usually poor abomasal motility, also called hypomotility, which allows gas and fluid to build up. Once the abomasum is distended and displaced to the right, it may rotate and twist.

Important risk factors include the period around calving, reduced rumen fill, high-concentrate and low-roughage diets, hypocalcemia, hypokalemia, ketosis, and concurrent diseases such as metritis or mastitis. Deep-bodied, high-producing dairy cows appear to be at higher risk, and most displacements happen within the first month after parturition.

In practical terms, this means abomasal volvulus often develops in cows already under metabolic and management stress. A cow that is fresh, not eating well, ketotic, or recovering from another postpartum illness may be more vulnerable than a stable herd mate.

Your vet usually starts with a physical exam, listening and percussing the abdomen for the characteristic right-sided ping. Rectal examination may help because a severely dilated abomasum can sometimes be reached more easily in volvulus than in simple displacement. History also matters, especially recent calving, sudden anorexia, sharp milk drop, and rapid dehydration.

Bloodwork often helps assess severity rather than making the diagnosis alone. Common findings include hypochloremic metabolic alkalosis, hypokalemia, dehydration, and sometimes rising lactate as circulation worsens. Higher heart rate, more severe dehydration, and elevated blood lactate can point to a poorer prognosis.

Ultrasound may support the diagnosis, but it does not always reliably distinguish a right displaced abomasum from abomasal volvulus. Because that distinction can be difficult and volvulus is so dangerous, cows suspected of having a right-sided abomasal emergency are often treated as surgical cases without delay.

Prevention focuses on transition-cow management. The biggest goals are maintaining rumen fill, supporting normal abomasal motility, and reducing postpartum disease. Adequate effective fiber, avoiding abrupt ration changes, and using a well-managed total mixed ration can help lower the risk of displacement and volvulus.

Your vet and nutrition team may also focus on preventing hypocalcemia, ketosis, metritis, and mastitis, because these problems can reduce feed intake and slow gut motility. Prompt treatment of fresh-cow illness matters. A cow that is off feed for even a short time after calving can move into a higher-risk category.

Good dry-cow and calving management also matter. Comfortable housing, consistent feed access, and close monitoring during the first month after calving can help catch appetite changes early. Prevention is rarely about one single fix. It is usually the result of steady transition management across nutrition, metabolic health, and postpartum monitoring.