Cryptosporidiosis

Introduction

This is a zoonotic, diarrhoea-causing, disease of cattle and other domestic livestock caused by the parasite Cryptosporidium. It is a protozoan parasite that inhabits crypt cells of the intestine. Transmission of the disease is faeco-oral. The disease is severe in humans and can be fatal in the immunocompromised. It causes severe sickness and diarrhoea for up to two weeks.

Clinical Signs

Often seen in adolescent calves, may present as a sudden outbreak or as sporadic disease. Animals may have weight loss and appear dull and depressed. Diarrhoea will be profuse and watery and may appear green/black.

Diagnosis

Clinical signs and age of cattle will provide a presumptive diagnosis. A faecal smear with Ziehl-Neelson (ZN) stain is diagnostic and if Cryptosporidium is present then oocysts stain red against a blue/green background. Immunoassays can also be performed to detect oocysts in faeces.

Control

Isolate/quarantine bought-in calves maintain good hygiene by providing adequate bedding and disinfecting calf pens.

If diarrhoea is present and Cryptosporidium has been detected then treat with halofuginon. This treatment is given orally.