Abomasal Displacement and Volvulus By Dr. Hussein

Pathophysiology
After abomasal atony, distention with gas produced by microbial fermentation occurs and most likely precipitates the displacement.
It has been hypothesized that the displacement will be oriented (left or right) according to the size of the rumen.
If the rumen is small and empty (as in the early postpartum period), the abomasum can move to the left and LDA can occur.
A large and filled rumen will make the left displacement less, likely, and the abomasum will dilate and in some cases twist to the right.<br>

Left Displacement of the Abomasum
Clinical signs
Reduced appetite (complete anorexia, reduced consumption of concentrates).
Milk production is reduced.
Ketosis is usuallypresent.
Rectal temperature is normal, unless a concurrent infectious problem ispresent (metritis, mastitis). Pulse and respiration rates are normal or slightly above normal.<br>

Ruminal contractions are decreased to absent and difficult to hear because the abomasum interferes with transmission of the sound.
The last one or two ribs on the left are sprung, but the abdomen is sunken in the paralumbar fossa.
Gurgling or tinkling rather than normal scratching sounds may be heard on auscultation in the left paralumbar fossa.
Simultaneous auscultation and percussion reveal a ping over the gas-filled portion of the abomasum. With LDA the area of ping may be anywhere from the lower third of the abdomen in the eighth intercostal space to the paralumbar fossa.<br>

Differential Diagnosis
Ruminal tympany, pneumoperitoneum, and collapsed rumen may all produce pings on the left side of the cow.
Physometra (air in the uterus) and dilation and displacement of the cecum to the left of the rumen (which is rare) may also produce left-sided pings.<br>

Note: tool use in diagnosis
used stomach tube passed into the rumen while auscultating over the left side differentiates the rumen from other structures.
Percutaneous needle aspiration of fluid or gas from the suspected abomasum aids in correct identification. A pH of less than 4.5 as or the odor of abomasal gas (slightly acrid or burned almonds) confirms the presence of LDA.
Ultrasound examination.<br>

Treatment and Prognosis
Treatment for LDA involves
Returning the abomasum to its normal anatomic location and preventing reoccurrence (“pexy”);
Treating the electrolyte, acid-baseabnormalities, and energy metabolism problems (ketosis and hepatic lipidosis); and providing therapy for concurrent disease conditions.<br>

Prognosis for LDA is good but is influenced by the severity of the concurrent disease.
Cattle with severe hepatic lipidosis and LDA should be given a guarded prognosis.
. The prognosis in animals suffering chronic indigestion with LDA of this group of cattle is poor because the primary disease is often more serious than the LDA .<br>

Right Displacement of the Abomasum
Simple right displacement of the abomasum (RDA) occurs at approximately 10% to 15% the frequency of LDA.
Clinical Signs
systemic state of the cow with a simple RDA is the same as that of the cow with LDA.
An area of tympanitic resonance is heard on the right side with simultaneous auscultation and percussion.
The ping usually is confined to an area under the last five ribs in the upper half of the abdomen.<br>

Differential Diagnosis
The condition must be differentiated from other causes of right-sided pings, such as
Cecal distention (with or without volvulus),.
Gas in the spiral colon.
Pneumorectum after rectal examination.
Pneumoperitoneum.
Physometra (gas in the uterus),.
Abomasal volvulus.
7.Abomasal volvulus is the most difficult to differentiate from RDA<br>

Treatment and Prognosis
Surgical treatment is required to correct RDA. Because of the difficulty of differentiating RDA from early volvulus, intervention should be as prompt as possible. The prognosis for a successful recovery after surgery is comparable to that for LDA if no other concurrent disease is present.<br>

Abomasal Volvulus
Abomasal volvulus, or right torsion of the abomasum, leads to complete obstruction of the flow of ingesta into the duodenum and therefore is a surgical emergency. The condition occurs in all classes ofcattle. Although RDA is thought to precede its development, unknown factors lead to abomasal volvulus<br>

Clinical signs
The systemic effects from abomasal volvulus more severe degree than in LDA or RDA. Sunken eyes and loss of skin turgor accompany the dehydration that develops.
Abdominal distention is marked bilaterally. Complete ruminal stasis develops, leading to bloat, and the abomasum greatly enlarges on the right.
The skin is cool to the touch. Feces are absent or watery but scant.
A large area of tympanitic resonance with uniform pitch throughout is detectable on the right, extending from the eighth rib to the middle of the paralumbar fossa.
Splashing fluid sounds can be heard when the abomasum is balloted (succussed) behind the last rib.
Death occurs within hours of this stage, which occurs 1 to 3 days after the development of the volvulus.<br>

Differential diagnosis
Other causes of proximal intestinal obstruction and torsion of the intestinal.
Treatment
Immediate surgical intervention usually is necessary to save the animal’s life.
At the same time, fluid, electrolyte, and acid-base abnormalities need correction.
For early cases of hypokalemic, hypochloremic alkalosis and dehydration, intravenous fluids consisting of 20 to 80 L of 0.9% sodium chloride with 25 to 100 mEq/L potassium chloride added are administered.
Broad-spectrum antibiotics are appropriate if the integrity of the abomasal mucosa is questionable.
NSAIDs are indicated to control pain, inflammation, and shock.<br>