Characterisation of a Cryptosporidium isolate from water buffalo (Bubalus bubalis) by sequencing of a fragment of the Cryptosporidium oocyst wall protein gene (COWP).

Cryptosporidium oocysts were detected using a direct immunofluorescence antibody test in the faeces of an asymptomatic water buffalo (Bubalus bubalis) heifer from a dairy farm close to Santiago de Compostela (NW Spain). Oocysts were morphologically indistinguishable from Cryptosporidium parvum. Using DNA extracted from this sample and a PCR-RFLP analysis of a 341 base pairs fragment of the Cryptosporidium oocyst wall protein (COWP) gene, a previously undescribed fragment pattern was generated. The COWP gene fragment was cloned and sequencing analyses revealed it to be similar to the C. parvum 'pig' genotype but with four base pairs substitutions.