Morphological study of Cryptosporidium oocysts in diarrhoeic calves

The present work was undertaken to study the morphology of Cryptosporidium oocysts recorded in diarrhoeic calves. For this purpose, a total of 306 faecal samples of diarrhoeic bovine and bubaline calves were screened for Cryptosporidium oocysts by Sheather's sugar flotation technique and positive faecal samples were examined by modified Ziehl-Neelsen staining technique for morphological study of oocysts. The study revealed that oocysts of Cryptosporidium species had a mean size of 7.4X5.5 μm and 4.85X4.17 μm giving the ovoid to ellipsoidal (shape index 1.33) and sub-spherical shapes (shape index 1.16), respectively. On the basis of oocyst dimensions and shape index, it was inferred that ovoid and subspherical oocysts belonged to Cryptosporidium andersoni and Cryptosporidium parvum, respectively.