Colitis in Grower Pigs - The Profit Stealer

David G S Burch  BVetMed DECPHM MRCVS

Veterinarian, Octagon Services Ltd

Published in "Pigs & Poultry Marketing" Late Spring 2010

Colitis is the term for inflammation of the large intestine or colon. Several bacteria can cause colitis, which usually causes diarrhoea in the pig but more recently the term 'colitis' has become associated with Brachyspira pilosicoli infections, the cause of Porcine Intestinal Spirochaetosis.

Jill Thomson and colleagues (1998) from SAC Veterinary Services in Edinburgh, Scotland reported on the prevalence of the different bacteria in a survey of 85 farms with grower diarrhoea (see Figure 1).


Figure 1. The main bacterial causes of 'colitis' in growing pigs

The main bacterial causes of 'colitis' in growing pigs

Many of the infections were mixed, but B. pilosicoli was the most frequently isolated as a single agent and combined, frequently with Lawsonia intracellularis, the cause of porcine proliferative enteropathy or 'ileitis'.

The infection tends to cause only mild, grey diarrhoea (see Photo 1) and it is impossible to distinguish it conclusively from other infectious agents without further diagnostic tests, including culturing, PCR and serology, a speciality of SAC in the UK.

Swine dysentery, caused by B. hyodysenteriae, is generally much more severe and the diarrhoea frequently contains blood and mucus and may kill pigs. Its effects on growth and feed conversion efficiency are also much greater in comparison with B. pilosicoli infections, although both bacteria occupy the same part of the gut, the deep crypts in the colonic mucosa. B. hyodysenteriae is generally more invasive and pathogenic.


Photo 1. Grey diarrhoea frequently associated with 'colitis'

Grey diarrhoea frequently associated with 'colitis'


From a recent UK survey of B. pilosicoli isolates, the majority were susceptible to both tiamulin (Denagard®) and valnemulin (Econor®), both products being approved for use against 'colitis'. Lincomycin (Lincocin®) is also active but there is extensive resistance to tylosin (Tylan®) (see Table 1).

Table 1. The minimum inhibitory concentrations (MICs) of various antibiotics
against 21 UK B. pilosicoli isolates (Pridmore, 2008)


MIC 50 (µg/ml)

MIC 90 (µg/ml)

Range (µg/ml)




≤0.008 – 4.0




≤0.008 – 4.0









Key: * = Indicated for use against 'colitis'


Even though B. pilosicoli causes a less severe problem in growing pigs than swine dysentery, it can still have a major economical impact on performance.

In a treatment study, Thomson and others (2006) showed that tiamulin improved consistently the performance of growing pigs between 9 and 15 weeks of age (see Table 2).


Table 2. Treatment of colitis affected pigs with tiamulin

Untreated controls Treated pigs
(tiamulin 100ppm for 7 days

No. of batches



No of pigs



Average daily gain (g)


880 (+16.2%)



1.77 (-12.8%)

Mortality (%)


0.92 (-15.60%)


The performance in the untreated pigs could be considered reasonably good demonstrating that B. pilosicoli does not exert a severely damaging effect, unlike B. hyodysenteriae but the treated pigs still grew 16.2% faster and had a better FCE by 0.25 (12.8%). Mortality was low in both groups but marginally improved in the tiamulin-treated groups.

Colitis appears to be a relatively common problem in young pigs but with good diagnostics and the right therapy, it is a disease that can be well controlled and its economic impact and 'profit-stealing' effect kept to a minimum.



Pridmore, A. (2008) Report to Novartis 'Antibacterial activity of tiamulin, valnemulin, tylosin and lincomycin against Brachyspira and Mycoplasma isolates: determination of minimum inhibitory concentration (MIC).

Thomson, J.R., Smith, W.J. and Murray, B.P. (1998) Investigation into field cases of porcine colitis with particular reference to infection with Serpulina pilosicoli. Veterinary Record 142, 235-239

Thomson, J.R., Murray, B.P., Henderson, L.E. and Edwards, S.A. (2006) A cost-benefit study on the control of porcine colonic spirochaetosis in a commercial grower unit. Proceedings of the 19th IPVS Congress, Copenhagen, Denmark Vol 2, p 350.


Copyright © Octagon Services Ltd  2010
Pig Health & Diseases:  Pig Therapeutics Articles
  top top  ~