Contact Details


Vet Associates Hastings

814 Francis Hicks Ave

Raureka, Hastings


Ph:   (06) 878 8666

Fax:   (06) 870 9109



Business Hours

Mon - Fri : 8am to 5.30pm

Sat : 9am to 12pm

Sun : 10am to 12pm

Bloat In Cattle PDF Print E-mail


Bloat is a common disease of cattle characterised by abdominal swelling, severe illness & often death, if not diagnosed & treated promptly. There are two main types of bloat:



'Frothy’ Bloat – caused by the ingestion of lush pasture, legumes (eg. Clover) or crops with high levels of rapidly fermentable carbohydrate, high protein & low fibre concentrations. The mixing of gas & ingested food produces a stable foam in the rumen which prevents the normal release of gas via the oesophagus (‘eructation’). Multiple animals within a mob are usually affected to varying degrees.


'Gaseous’ Bloat – caused by prevention of normal gas release due to obstruction of the oesophagus, either by a foreign body or acute/chronic damage to the oesophageal opening into the rumen. Far less common than Frothy Bloat, and usually only affecting individual animals.


In both cases, the extreme pressure of the distended rumen on other body systems & organs, particularly the blood vessels & the lungs, can rapidly send the affected animal into shock, major organ failure & eventual death.


Clinical Signs

Signs of bloat can occur as soon as one hour after putting cattle onto ‘risky’ pasture or feed. Initial signs may be limited to swelling/distension over the left upper abdomen, gradually extending over the whole abdomen, with the animal displaying various signs of discomfort, including bellowing, restlessness, kicking & lying down. In advanced cases, the animal will show signs of severe respiratory distress, including open mouth breathing, drooling & protruding tongue. Animals which are down, usually die fairly quickly of asphyxiation and/or heart failure.



Successful treatment of bloat requires early diagnosis & intervention to provide the greatest chance of success. In some cases, even early treatment can be too late to prevent irreversible organ damage and the animal may never fully recover.

Treatment options include; immediate removal of animals/mobs from ‘at-risk’ feed, use of oral bloat drenches or as a last resort, an emergency rumenotomy (‘stab’).

Bloat drench products (eg. Bloatenz) are the main stay of treatment for mild to moderate cases, with dosing recommendations varying by product. Always follow the guidelines on the packaging for dose & dilution rates. If the animal is unable to swallow or you suspect death is imminent, an emergency ‘stab’ with a sharp knife or trocar into the left upper abdomen (mid-way between last rib & pin bone, hand-span below vertebrae, towards opp. elbow) may save her life through the sudden release of pressure. Use a non-slip, non-folding knife & be prepared to get sprayed! Call your vet as soon as possible to repair the wound as ruminal contents leaking into the abdomen can result in a life-threatening peritonitis over the following days.



Given the variable response to treatment, identifying & avoiding the risk factors for bloat, and using preventative options are far more prudent measures. Risk factors include; highly digestible feed (eg. Clover, fresh pasture), recent fertiliser application & hungry animals. Preventative options include; oral bloat drenches, either administered directly or via water reticulation & pasture spraying, intra-ruminal bloat devices eg. Bloat Capsules, provision of fibrous supplements or poorer quality pasture prior to allowing animals onto risky feeds.

Oral bloat formulations can be applied in a variety of ways, although with the exception of milking cows, oral drenching is probably the least feasible due to the requirement for it to be done daily (twice daily in high risk situations). Bloat products can be applied as flank applications (eg. ingested through licking), using water trough dispensers, bloat licks and by spraying ‘at-risk’ feed breaks. These methods (with the exception of bloat licks) also have the advantage of allowing dose rates to be increased when bloat risk is high. Intra-ruminal bloat capsules are also a useful tool where frequent treatments are less manageable or desirable. They need to be administered 5-7 days prior to the expected bloat challenge & in severe cases, animals may still require additional treatment in the form of oral bloat drenches. Most capsules will last for roughly 100 days. Be advised, many bloat drenches & bloat capsules are highly toxic to dogs & horses - if they are ingested by these species they will probably die. Trough dosing & regurgitated capsules are particularly high risk for poisoning events.


For further information about Bloat, its causes, prevention & treatment, please contact the clinic on (06) 878 8666 to speak to a veterinarian directly.

Last Updated on Tuesday, 29 September 2015 16:47