Encapsulated loculated abscess in older SPF swine

a case report and discussion

Abstract

• Background: 
  Abscesses are a common problem in humans, and the diagnosis and treatment of the condition is established.  It is also seen occasionally pigs, but this is poorly documented in the literature. Treatment is often observational, with culling of the affected animal as necessary—inadequate treatment methods are often propagated in non-clinical farming resources. The aim of this report is to describe a simple, modern, effective approach to diagnosis and treatment of abscesses in pigs which is based on human medical practice, and to underscore the importance of this simple intervention in both laboratory and agricultural settings.
• Case presentation: 
  The following report describes an encapsulated and loculated abscess in an SPF laboratory pig, presenting at an injection site two months after legally mandated vaccination with CSF vaccine. Despite SPF laboratory conditions, the abscess progressed. Clinical ultrasonic diagnosis revealed an encapsulated and loculated abscess. Incision and drainage was performed, with antibiotic lavage and post-procedure prophylaxis. The animal recovered uneventfully.
• Conclusions: 
  The clinical presentation and presence of atypical gram-negative rods in the abscess pus establishes this abscess as a likely injection site infection, likely from fecal matter contamination. This occurred despite standard clinical precautions in an SPF-grade facility. One exacerbating factor may be the absence of antibiotic supplementation in our experimental feed mixture. Injection site abscesses are of increasing relevance as pigs and other farm animals receive increasing vaccinations, and minipigs in particular are increasingly kept past their prime meat age at 6 months for laboratory research into aging and chronic conditions, and as companion animals. Although abscesses are easily treatable, they are usually exquisitely painful and may lead to systemic spread and death. Therefore, for humanitarian reasons and for reasons of increased sustainability in livestock farming and for good laboratory experimental practice, conditions such as abscess must be treated rapidly and appropriately as described in this case report.