F08
Abomasal Problems

left displaced abomasum (lda) | right displaced abomasum (rda) and abomasal volvulus (rta) | abomasal ulcers

Introduction/Causative Agents: Left displaced abomasum (LDA) occurs when the animal’s abomasum, a part of the cow’s stomach, becomes displaced to the upper left side of the rumen. The animal’s digestive system can slow down or stop, and the abomasum can bloat (fill with gasses). LDA is usually more commonly seen than right displaced abomasum (RDA). While the precise cause of LDA is unknown, it is usually linked with some type of stress that is placed on the cow. This can be conditions such as bad weather, disease, or most commonly, a diet that is high in concentrates with very little large-particle hay.

Clinical Signs: Many cattle with LDA show no interest in eating, have fewer or looser bowel movements, and often do not chew their cud. When listening with a stethoscope on the left side of the rumen near the last rib, a distinct "ping" can sometimes be heard when thumping the area with a finger.

Diagnosis: After observing the clinical symptoms, a preliminary diagnosis can be made. A urine test on LDA cattle will usually reveal ketones, glucose, and an acidic pH. Cattle can be hypoglycemic and dehydrated. Blood work may reveal metabolic alkalosis and electrolyte levels higher than normal. Hearing the distinct "ping" with a stethoscope will also aid in the diagnosis.

Treatment: The most common treatment for LDA is to surgically move the abomasum back to its correct position. This usually involves tacking the abomasum to the lower abdominal wall of the animal with suture in order to prevent future displacements. A few animals may require IV therapy to counteract the body chemistry changes. Some animals are then placed antibiotics and gut stimulants (Probios, etc.).

Prevention: A few studies have shown that exercise may help prevent the occurrence of LDA. Other studies state that keeping the animals on large-particle hay rather than small-particle hay and slowly introducing concentrates after calving may help prevent LDAs. Additional prevention ideas and details about LDAs can be found on page A579 of the Dairy manual.

Introduction/Causative Agents: Right displaced abomasum (RDA) occurs when the animal’s abomasum, a part of the cow’s stomach, becomes displaced to the right side of the rumen. RDA is similar in many ways to LDA, but is usually not seen as often. Like animals with LDA, RDA can cause the animal’s digestive system to slow down or stop, and the abomasum can bloat or fill with gasses.

Occasionally, the abomasum can also twist as it is displaced in what is called abomasal volvulus (RTA). RTA is seen less often than LDA or RDA, but it is more serious. RTA can cause a major obstruction in the animal’s digestive tract and requires immediate corrective surgery. RDA and RTA are very similar in terms of symptoms and are difficult to tell apart. While the precise cause of RDA and RTA is unknown, these conditions are usually linked with stress, bad weather, or the consumption of smaller-particle hay.

Clinical Signs: Similar in many ways to LDA, cattle with RDA or RTA usually show no interest in eating, have fewer or looser bowel movements, and often do not chew their cud. Some cows also become dehydrated. When listening on the right side of the cow in the flank area with a stethoscope, a distinct "ping" may be heard when thumping the area with a finger. RDA and RTA are often times so similar in the earlier stages that telling them apart is close to impossible. However, as the condition progresses, animals with RTA usually develop much worse symptoms and dehydration much faster than an animal with RDA. RTAs usually accumulate fluid in the abomasum, which can be detected by listening with a stethoscope.

Diagnosis: After observing the clinical symptoms and hearing that distinct "ping," a preliminary diagnosis can be made. A urine test on RDA cattle will usually reveal ketones, an acidic pH, and possibly even glucose. Cattle can be hypoglycemic and dehydrated. Blood work may reveal metabolic alkalosis and electrolyte levels higher than normal.

Treatment: The most common treatment for RDA is to surgically move the abomasum back to its correct position. This usually involves tacking the abomasum to the lower abdominal wall of the animal with suture to prevent future displacements. Because of the possibility of RTA, surgery should be done as soon as possible. A few animals may require intravenous (IV) therapy to counteract the body chemistry changes. Some animals are then placed on gut stimulants and antibiotics.

Prevention: Prevention for RDAs is the same as it is for LDAs.

Introduction/Causative Agents: Abomasal ulcers can occur in cattle of all ages. They are usually caused by stress, diet, or abrupt changes in rations. Ulcers form when the lining of the abomasum thins or is lost altogether. The stomach acids then eat away at the tissue of the abomasum, causing irritation and bleeding. If left untreated, the stomach acids may eat all the way though the abomasum, and the animal can suffer from peritonitis (inflamed and irritated abdomen).

Ulcers are usually separated into four types: (1) non-perforating, (2) non-perforating with severe blood loss, (3) perforating with local peritonitis, and (4) perforating with diffuse peritonitis. Numbers (1) and (2) describe ulcers inside the abomasum which can either bleed a little or a lot. Numbers (3) and (4) describe ulcers that have eaten all the way through the wall of the abomasum and are allowing stomach acids to leak inside the animal’s abdominal cavity, causing either local peritonitis (smaller, more localized irritation) or diffuse peritonitis (irritating a large area inside the animal’s abdominal cavity).

Clinical Signs: Both non-perforating ulcer types usually cause similar symptoms in the cow. The cow will often eat less and have blood in the feces. Animals with non-perforating ulcers that suffer severe blood loss also can show signs of anemia, including pale gums and cool limbs. Sometimes the heart rate can be a little bit faster than normal as well. On the other hand, animals that have perforating ulcers usually do not eat at all. They will often show signs of dehydration, and they might have a slight fever. If left untreated, the fever can turn into hypothermia as the ulcer worsens. They can have a large amount of blood in their feces and also show signs of anemia (pale gums and cool limbs). Their heart may beat faster than normal, and they can show signs of abdominal pain or grunt as they breathe. In severe cases, some cows may go into shock.

Diagnosis: Often, the most useful test for diagnosing abomasal ulcers is to check the feces for blood. Blood work may reveal low levels of plasma proteins, and in animals with severe blood loss, a low packed cell volume might be found. Another test for more severe cases is called abdominocentesis, where fluid can be drawn out of the abdomen with a needle to check for peritonitis. Cattle with bleeding ulcers that are over 5 years old should also be tested for the Bovine Leukosis Virus (BLV). BLV can cause lymphosarcoma, which can result in abomasal ulcers.

Treatment: Treatment may include removing stress factors such as overcrowding or high competition for food. It may be helpful to gradually change the animal’s diet by removing starchy foods and add good quality hay. Cattle that have lost a lot of blood may require a blood transfusion. Antacids are often used, but they may or may not help because they are usually diluted in the rumen and are released slowly into the abomasum. Treatment with Cimetidine may help reduce stomach and gastric secretions. Most cattle are placed on antibiotics, and some cases require intravenous (IV) fluids.

Prevention: Good management of diet and environment to reduce stress is a good way to help to prevent abomasal ulcers. Avoiding abrupt ration change, and using a higher particle diet can also be beneficial.