Clinical signs

Acute disease
This occurs where the virus is introduced into a susceptible population for the first time. In such cases up to 100% of sows may be affected, showing a mild to very watery diarrhoea. Two clinical pictures are recognised: PED Type I only affects growing pigs where as PED Type II affects all ages including sucking pigs and mature sows. The incubation period is approximately 2 days and the disease episode lasts for 7 to 14 days. In sucking pigs the disease can be mild or severe with mortalities up to 40%.

Endemic disease
In large breeding herds, particularly if kept extensively, not all the females may become infected first time round and there may be recrudescence. This only occurs in piglets suckling from sows with no maternal antibodies and it is therefore sporadic.

Diagnosis

This can be suspected on the clinical signs but it cannot be differentiated from TGE. If acute diarrhoea is occurring in weaned and older animals on a growing/finishing farm with no symptoms in sucking piglets then this would suggest PED Type I. PED Type II would affect piglets. Virus particles from diarrhoea samples can be identified under the electron microscope but this would not differentiate PED from TGE. Blood tests can be carried out to look for rising antibody titres. An ELISA test is also available for examining diarrhoea samples or intestinal contents.

Treatment

• Because this is a virus infection there is no specific treatment but often secondary bacteria complicate the picture and these can be treated by broad spectrum antibiotics such as neomycin, framycetin, apramycin or trimethoprim/sulpha.
• If the virus enters the herd for the first time it is important to ensure that all the adult animals become infected at an early stage to allow an early immunity to develop. This can be achieved by exposing sows to the diarrhoea three times, two days apart via the drinking water. Mix scour or contaminated material into a bucket of water and use this as the source .