Signs develop within 24 to 48 hours.

Clinical signs

The very early stages of disease are always preceded by inappetence and whenever a sow or groups of pigs are not eating always check the water supply first. The first signs are often pigs trying to drink from nipple drinkers unsuccessfully. Nervous changes are the major signs and in more advanced cases involve fits, with animals wandering around apparently blind. Often the pig walks up to a wall, stands and presses its head against it in a characteristic position. One symptom strongly suggestive of salt poisoning is nose twitching just before a convulsion starts.

Diagnosis

This is based upon the clinical signs and lack of water. Examination of the brain histologically at post-mortem confirms the disease.

Similar diseases

Aujeszky's disease, swine fever, streptococcal meningitis and glässers disease all produce nervous signs. The condition might also be confused with middle ear infection but this only affects one individual rather than a group of pigs.

Treatment

• The response to treatment is poor but involves rehydrating the animal. At a practical level this can be achieved by dripping water into the mouth of the pig through a hose pipe or alternatively via a flutter valve into the rectum where it is absorbed. (See chapter 15 Flutter valve).
• Discuss the possibility of administering sterile water into the abdomen with your veterinarian.
• Corticosteroids may also help.