Comparison of different diagnostic techniques for the detection of cryptosporidiosis in bovines

AIM: Aim of the present study was to compare different methods, viz., Sheather's sugar flotation (SSF), Ziehl-Neelsen (ZN), Kinyoun's acid-fast method (KAF), safranin-methylene blue staining (SMB), and negative staining techniques such as nigrosin staining, light green staining, and malachite green staining for the detection of Cryptosporidium spp. oocysts in bovines. MATERIALS AND METHODS: A total of 455 fecal samples from bovines were collected from private, government farms and from the clinical cases presented to Department of Medicine, Veterinary College, Bengaluru. They were subjected for SSF, ZN, KAF, SMB and negative staining methods. RESULTS: Out of 455 animal fecal samples screened 5.71% were found positive for Cryptosporidium spp. oocysts. The species were identified as Cryptosporidium parvum in calves and Cryptosporidium andersoni in adults based on the morphological characterization and micrometry of the oocysts. CONCLUSIONS: Of all the techniques, fecal flotation with sheather's was found to be more specific and sensitive method for the detection of Cryptosporidium spp. oocysts. Among the conventional staining methods, the SMB gives better differentiation between oocysts and yeast. Among the three negative staining methods, malachite green was found sensitive over the other methods.