Gastric Ulceration - Pig

Gastic ulceration is quite common in the pig- May be seen in 50-60% of pigs arriving at slaughterhouses.
Has serious economic consequences.

Clinical
- Occasionally a well-grown pig will drop dead.
  - Deep ulcers have eroded into a blood vessel, causing massive haemorrhage into the stomach from and producing death very rapidly.
- If long standing ulcers do not result in death, they do produce pain and discomfort.
  - Give low growth rate and poor feed conversion.

Pathogenesis
- Gastric ulceration is associated with modern pig rearing, but the exact cause is unknown.
- Causes are associated with gastric hyperacidity, and gastric ulceration is probably a multifactorial disease.
- The following are suggested as possible causes:
  - Infection, e.g. Candida albicans, Streptococci, Staphylococci and mixes of these.
  - Copper toxicity- this is probably more significant.
    - Pigs are fed copper as growth promoter; 50 ppm is know to be toxic, and animals are often fed 250 ppm.
  - Vitamin E / Selenium deficiency.
  - Feeding on concrete floors.
    - Sand is licked up whe pigs eat.
  - Feeding finely milled cereal.
  - Stress
  - Possibly genetic factors.

Pathology
- Most commonly affects pars oesophagea (squamous or non-glandular portion).
- Starts with hyperkeratosis in the stratum corneum
  - Appears rough and thickened
  - May stop at this stage.
- In approximately 30% of animals, the lesion starts to erode and quite deep ulcers may develop.
- In a significant small number ,very deep ulcers develop and may affect virtually all of pars oesophagea.
- Histologically, ulcers are large and flask-shaped ulcer with fibrin, necrosis, erosion and fibrosis at base.