Cryptosporidium spp

From Cow
Bovine intestinal impression smear showing acid-fast (red) Cryptosporidia with round and faint halos.

Cryptosporidium spp are a parasitic protozoa of cattle worldwide, primarily causing scours in calves, causeing economic losses due to cattle death and treatment, and indirectly via decreased milk production capacity and increased production cost[1][2].

Co-infection with rotavirus, coronavirus, or enterotoxigenic Escherichia coli is common[3]. Diarrhea can result from a monoinfection, but more commonly is associated with mixed infections. The source of infection is oocysts that are fully sporulated and infective when excreted in the feces.

Clinical signs are usually limited to diarrhea, but dehydration, lethargy and fever can be seen with secondary bacterial infections.

Diagnosis is based on detection of oocysts by examination of fecal smears with Ziehl-Neelson stains, by fecal flotation, or by immunologically assisted methods.

There is no effective chemo-therapeutic agent for routine treatment of cryptosporidiosis, but supportive care is recommended.


  1. Chen F & Huang K (2012) Prevalence and molecular characterization of Cryptosporidium spp. in dairy cattle from farms in China. J Vet Sci 13(1):15-22
  2. Budu-Amoako E et al (2012) Giardia and Cryptosporidium on dairy farms and the role these farms may play in contaminating water sources in Prince Edward Island, Canada. J Vet Intern Med 26(3):668-673
  3. Panciera RJ et al (1971) Cryptosporidial infection in a calf. Vet Pathol 8:479–484