In this study published in BMC Veterinary Research, the following lung lesion scoring methods were compared for the assessment of the different pathological outcomes derived from an Actinobacillus pleuropneumoniae (App) experimental infection model.:

• Slaughterhouse Pleurisy Evaluation System (SPES)
• Consolidation Lung Lesion Score (LLS)
• Image analyses (IA) and
• Ratio of lung weight/body weight (LW/BW)

Moreover, the researchers including first-named author Marina Sibila of Centre de Recerca en Sanitat Animal (CReSA) explain, pathological data was coupled with clinical (fever, inappetence and clinical score), production (average daily weight gain (ADWG) and diagnostic (PCR, ELISA and bacterial isolation) parameters within the four infection outcomes (peracute, acute, subclinically infected and non-infected).

From the 61 inoculated animals, nine were classified as peracute (presence of severe App-like clinical signs and lesions and sudden death or euthanasia shortly after inoculation), 31 as acutely affected (presence of App-like clinical signs and lesions and survival until the end of the experiment), 12 as subclinically infected (very mild or no clinical signs but App infection confirmed) and nine as non-infected animals (lack of App-like clinical signs and lack of evidence of App infection).

A significant correlation between all lung lesion scoring systems was found with the exception of SPES score versus LW/BW. SPES showed a statistically significant association with all clinical, production and diagnostic (with the exception of PCR detection of App in the tonsil) variables assessed.

LLS and IA showed similar statistically significant associations as SPES, with the exception of seroconversion against App at necropsy.

In contrast, LW/BW was statistically associated only with App isolation in lungs, presence of App-like lesions and ELISA OD values at necropsy.

Sibila and co-authors concluded SPES, LLS and IA are economic, fast and easy-to-perform lung scoring methods, which (in combination with different clinical and diagnostic parameters) allow the characterisation of different outcomes after App infection.

Reference

Sibila M., V. Aragón, L. Fraile and J. Segalés. 2014. Comparison of four lung scoring systems for the assessment of the pathological outcomes derived from Actinobacillus pleuropneumoniae experimental infections. BMC Veterinary Research. 10:165. doi:10.1186/1746-6148-10-165

September 2014