Veterinary Services

Postweaning multisystemic wasting syndrome (PMWS), porcine dermatitis nephropathy syndrome (PDNS) and parasitic dermatitis (sarcoptic mange) were confirmed in a four-month-old boar submitted for postmortem examination. The boar was one of a group of 20 taken onto a unit and into isolation one month previously. Some of the boars developed a skin rash which was non-responsive to antibiotic treatment and ill thrift was reported in four or five of the boars. The boars reputedly had come from a mange-free source and diagnosis of the infestation while animals were in isolation safeguarded the mange-free status of the recipient herd. The cause of ill thrift in the other affected boars was not investigated.

Alimentary tract disorders

Faecal samples submitted from growing pigs showing diarrhoea and ill thrift on one unit failed to identify any potential bacterial causes of diarrhoea. However, Oesophagostomum dentatum eggs were detected in all three faecal samples, with particularly high numbers being present in one case (4200 eggs per gram).
Pooled faecal samples from diarrhoeic finishing pigs on an unrelated unit yielded Yersinia pseudotuberculosis on culture and Brachyspira pilosicoli and Lawsonia intracellularis by PCR.  Salmonella species were not isolated.

Rectal stricture presented as a problem in approximately two per cent of pigs weighing between 25 and 60 kg on another unit. Typically, affected pigs were reported to show liquid scour and develop a pot belly with subsequent chronic ill thrift necessitating eventual euthanasia. The diagnosis was confirmed by postmortem examination of typical cases. No Salmonella species were isolated from pigs submitted for postmortem examination. No samples were received from pigs at the earlier stages of the disease process.

As part of an investigation into intestinal tracts of five-month-old finishing pigs at the abattoir, thickened ileums grossly suggesting of proliferative enteropathy were collected. Further examination including histopathological examination of representative areas was undertaken. Among these cases there were six pigs in which the ileal mucosa was within normal limits but the internal and external muscularis layers were extremely hyperplasic. As a result, the muscle layers were approximately four times the normal thickness for pigs of this age. A distinct band of stricture within the last 15 cm of the terminal ileum was evident in two cases. The findings suggested that a condition similar to rectal stricture can affect the ileum of pigs. This causes the ileum to have a macroscopic appearance which could be confused with that of proliferative enteropathy caused by Lawsonia intracellularis infection.