Differentiation of porcine Eimeria spp. by morphologic algorithms

Oocysts of Eimeria spp. were isolated from feces of naturally infected sows by conventional flotation. Saturated sodium chloride solution was superior to zinc chloride, zinc chloride/sodium chloride or sugar solution to isola te oocysts. Seven species, namely Eimeria scabra, E. polita, E. perminuta, E. debliecki, E. suis, E. porci and E. spinosa, were identified. The dimens ions of oocysts (n = 4088) and sporocysts (n = 3594) were measured with an image analysis system; colour and shape of oocysts were estimated and trans formed to numerical values. Olf the 4088 oocysts approximately 99% were all ocated to the correct species by algorithms calculated on the basis of thes e values. Rough-walled oocysts (E. scabra, E. polita, E. perminuta, E. spin osa) could be distinguished without previous sporulation in most cases (>97 %). Smooth-walled oocysts require sporulation for further classification an d were accurately allocated to species in at least 93% of cases. (C) 1999 E lsevier Science B.V. All rights reserved.