Bloat

Gastric dilatation volvulus (also known as twisted stomach, gastric torsion and GDV) is a medical condition in which the stomach becomes overstretched and rotated by excessive gas content. The word bloat is often used as a general term to cover gas distension without twisting and is often a normal change after eating or with aerophagia. It is sometimes used incorrectly to indicate gastric torsion. Gastric dilatation volvulus always involves the twisting of the stomach and is a life-threatening condition that requires prompt treatment. The condition occurs commonly in domesticated animals, especially certain dog breeds. Deep-chested breeds are especially at risk. Mortality rates in dogs range from 10 to 60 percent, even with treatment. With surgery, the mortality rate is 15 to 33 percent.

Gastric dilatation volvulus in dogs is likely caused by a multitude of factors, but in all cases the immediate prerequisite is a dysfunction of the sphincter between the esophagus and stomach and an obstruction of outflow through the pylorus. Some of the more widely acknowledged factors for developing gastric dilatation volvulus include increased age, breed, having a deep and narrow chest, stress, eating foods such as kibble that expand in the stomach, overfeeding, too much water consumption in a small period of time before or after exercise and other causes of gastrointestinal disease and distress. Studies have indicated that the risk of bloat in dogs perceived as happy by their owners is decreased, and increased in dogs perceived as fearful. This may be due to the physiological effects of the dog's personality on the function and motility of the gastrointestinal system. Alternatively, the dogs may become unhappy/uncomfortable as a consequence of the conditions that lead up to exhibiting bloat. Dogs with inflammatory bowel disease may be at an increased risk for bloat.

One common recommendation in the past has been to raise the food bowl of the dog when it eats. However, studies have shown that this may actually increase the risk of gastric dilatation volvulus. Eating only once daily and eating food consisting of particles less than 30 mm in size also may increase the risk of gastric dilatation-volvulus. One study looking at the ingredients of dry dog food found that while neither grains, soy, nor animal proteins increased risk of bloat, foods containing an increased amount of added oils or fats do increase the risk, possibly due to delayed emptying of the stomach.

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