Short communication. Sarcocystis infection: a major cause of carcass condemnation in adult sheep in Spain

Abstract

The frequency, distribution and impact of small ruminant Sarcocystis infection in the European Union is largely unknown; this study reports the prevalence of macroscopic Sarcocystis sp. cysts and associated carcass condemnation, in 6065 adult, cull, small ruminants from 145 farms in Spain. Macrocysts were detected in 12% of sheep from 60% flocks, and in none of the 345 goats examined. Most affected sheep had cysts in more than one body part and as a result, 79% of sheep carcasses with cysts were totally condemned. Consequently, it is estimated that Sarcocystis spp. infection could be costing the Spanish sheep industry € 20 million yr^-1. Three types of cysts were identified according to size, shape and location: narrow, filament-shaped measuring 2-10 × ≤1 mm, present striated muscles only, and two wider types measuring 2-20 × 2-6 mm, including oval-shaped oesophageal cysts and more elongated cysts in striated muscles. Narrow and wide macrocysts were found in the same sheep and are compatible with Sarcocystis gigantea and Sarcocystis medusiformis, respectively, as described in New Zealand in the 1970s. However, cyst size and morphology varies with age and location. Moreover, S. medusiformis has not been reported in Europe and species-specific diagnosis is necessary to ascertain the ethiology of macrocysts in this study.