VSR 421: Regional Veterinary Surgery (2+1)

BLOAT

• It is one of the major problems of the GI tract of cattle and buffaloes. Bloat can either be acute or chronic.
• In both cases, it is either accumulation of free gases in the dorsal part of the rumen or gases are dispersed throughout the rumen contents to cause frothy bloat.

Acute bloat

• Rapid feeding and sudden change of diet appear to predispose cattle and buffaloes to development of acute bloat.
• Esophageal obstruction
•  Presence of amphistomes at the cardia of the stomach.
• In small ruminants, ingestion of large quantities of cereals causes development of acute bloat which can be of serious nature. The increased intra-ruminal pressure due to accumulation of gases exerts pressure over the diaphragm and the ribs, which results in reduced respiratory movements. This will resulting hypoventilation and reduced venous return to heart.
• The increased intra-ruminal pressure also causes absorption of gases, particularly poisonous methane which has a deteriorating effect on the  the animal.
• The clinical signs include bulging of the paralumbar fossa in the early stages and entire abdominal distention in the later stage. Abduction off the forelimbs, especially at the elbows and reluctance to move are the other clinical features. There will be also absence of rumen motility.
• The mucous membranes are found cyanotic. In advanced stages, the animal keeps the mouth open and tongue protruded. Tachycardia in the initial stages many change later into a weak, slow pulse.
• Most common practices in relieving acute bloat is to insert a trocar and cannula into the upper flank region of  rumen. In the case of simple tympany, trocarisation alone may be enough to relieve the gas. But, if the bloat is frothy,  administration of anti foaming drugs into the rumen is mandatory inorder to free the gas eiether through a probang or trocar.
• Oral administration of 80 ml of turpentine mixed with 500 to 1000 ml of mustard oil is found to be very effective. Antifroth agents like dimethicone also can be used for this purpose.
• After severe bloat, concentrates should be avoided for atleast two days and the animal should be fed with non leguminous hay. In goat and sheep, the mortality rate is high, if the treatment is delayed and emergency rumenotomy also fail to save small ruminants.

Chronic bloat

• The most common cause of recurrent tympany in cattle and buffaloes is foreign body syndrome.
• Traumatic reticulitis and diaphragmatic hernia are the two common conditions in buffaloes where recurrent and chronic bloat in observed. Large omental, spleenic and hepatic cysts in bullocks have also been observed to cause recurrent lympany.
• Other conditions in which chronic bloat occurs in bovine include functional reticulo-omasal and pyloric stenosis (vagal indigestion), liver abcesses, enlarged mediastinal lymph nodes pressing oesophagus, mega oesophagus stricture at the cardia and neoplasms.
• The treatment in such causes is directed at the primary cause. Rumen fistulation (Rumenostomy) may be done  
• Per rectal findings of a collapsed dorsal sac of the rumen along with ventral displacement of left kidney in the mid abdomen, the  
• Treatment is purely medical and aimed at correction of primary disease and also the correction of fluid, acid-base and electrolyte imbalances.