Non Specific Colitis


Causal agent

None identified. Diarrhoea of weaned pigs of any age from weaning to slaughter.  Diarrhoea can occur within hours of consuming a new batch of pelleted feed and they can dramatically cease within hours of the removal of the suspect feed.  Considered important factors are nutrition, infectious agents, and draughts

Age group

Weaning to slaughter pigs, most common between 25-30 kg pigs

Clinical signs

Softening of faeces with/without mucus and/or blood

Diarrhoea can develop

Decreased growth rate.   Feed conversion increases

Most common between 8-10 weeks of age

More commonly seen in fast growing pigs on high density diets



Agent not recognised, but can appear to spread around and between farms

The syndrome classically occurs with a particular feed and when this is changed the ‘disease’ disappears.  Nutritional factors known to affect digestion are:

Presence of trypsin inhibitors in peas, beans and soya

Poor quality fat

Post-mortem Lesions

The colon and small intestine may demonstrate areas of inflammation both acute and chronic.  The spiral colon contains abundant watery green or yellow mucoid and frothy contents.  In some cases there may be no gross lesions.


The photograph shows raised rugae in the inside of the large bowl but few other lesions



Based on the clinical signs and absence of other specific organisms


Improve the environment, remove draughts and ensure that the stocking rate is correct – photo shows a growing shed being examined for draughts

Do not place pigs into buildings which are damp and cold

Check and clean the water supply

Ensure the correct pig is placed in the building

Change the feed to a meal

Establish an all-in/all-out programme

Common differentials


Other causes of post-weaning diarrhoea