Bloat in Calves
October 2022

Recently, I had a call out to see a 3.5 week old beef calf with recurrent bloat. She had recently been treated for cryptosporidiosis and despite still having some diarrhoea, was her normal, gusty self when she was fed 3 L of milk replacer at 7 am but by noon had become bloated and had been kicking at her gut.

She made no attempt to move when I entered the pen and had an abnormal stance and bloated left abdomen. She had been seen by a vet the week prior for similar episode. For both vet visits, treatment involved releasing the gas from the rumen via a needle and giving pain relief in the form of an anti-inflammatory and an antispasmodic agent.

Whilst the gas was being drained, a small amount of milk was seen in the needle, confirming milk to be in the rumen – not where we want it!

The calf did not drink that night but was bright and readily drank electrolytes the next morning. Milk was re-introduced in an evening feed, and within a few hours she had started to bloat up again. She was not showing signs of colic but was pre-emptively given another dose of an anti-inflammatory and an anti- spasmodic. By the next morning she had ‘deflated’ and was again bright and hungry.

There are several causes for bloat. As milk was found in the rumen, one potential cause could be a fault in the oesophageal groove reflex which is where normally, in response to suckling, a muscular channel forms to direct milk to the portion of the gut that can digest it (the abomasum) bypassing the rumen. When milk enters the rumen it can’t undergo normal digestion and instead ferments which can cause acidosis, gut microflora disruption and bloating. This phenomenon is also known as ruminal drinking.

Risk factors for ruminal drinking:

  • Irregular feeding times
  • Milk composition variability
  • Bucket feeding
  • Infection/scours
  • Drinking speed
  • Feeder height
  • Stressors e.g. Transportation

Currently the calf is being managed by alternating between milk and electrolytes on a twice daily feeding regime and has ad lib hay, grass and meal with added optiguard. She is being fed on a feeder with an adjustable flow speed and the height of the feeder has been brought down to nose level in a bid to better control the flow of milk. In addition to this, eating of meal and roughage is being encouraged and the calf is allowed to suckle the rearer’s fingers prior to feeding to help stimulate the oesophgeal groove reflex. Due to the recurrent nature of these episodes, the prognosis is guarded with condition and progress being evaluated on a daily basis.