Bloat is caused by a build-up of gas in the abdomen that is unable to escape. There are two main types of bloats in calves; abomasal bloat and ruminal bloat. Feeding consistency, colostrum management and good hygiene of feeding equipment are the main ways to avoid cases of bloat.

Bloat is caused by a build-up of gas in the abdomen that is unable to escape. There are two main types of bloats in calves; abomasal bloat and ruminal bloat. Feeding consistency, colostrum management and good hygiene of feeding equipment are the main ways to avoid cases of bloat.

Abomasal bloat tends to occur in younger calves aged 1-3 weeks old. They are usually acute and can be life threatening. Abomasal bloat will cause a right sided bloat, pain and will often be fatal within 6-48 hours. Many different factors can contribute to bloat including hygiene, feeding and abomasal ulcers. Management includes passing a stomach tube and treating medically with pain relief and antibiotics after discussion with your vet. Some cases will resolve but are often fatal due to septicaemia when bacteria enter the blood stream. It is important to review management and hygiene protocols to prevent further cases.

Ruminal bloat will present as a left sided abdominal distension and occurs in older calves when their rumens have started to develop. A ruminal bloat may be a consequence of oesophageal groove dysfunction where milk bypasses the abomasum and enters the rumen where it is fermented and causes bloat. It is important not to tube feed milk for this reason. Previous cases of pneumonia can predispose calves to bloat due to vagal nerve damage and enlargement of lymph nodes which causes compression on the oesophagus and prevents eructation (“burping”).
In acute cases, passing a stomach tube can reduce the bloat, however depending on the primary cause, it may reoccur. A trocar or ‘red devil’ is an option to release gas from the rumen. This is often successful in resolving the problem, however in some cases after a few weeks when the trocar has worked itself out, the bloat may reoccur.
A rumen fistula is a permanent surgical solution which can be used in reoccurring bloats due to vagal nerve damage. As with any surgery, there is a risk of infection, but most go on to be healthy adult cows with no complications – and no bloat!