Bovine besnoitiosis is a protozoal disease of cattle caused by infection with the cyst-forming apicomplexan parasite Besnoitia besnoiti. The disease is of particular concern for cattle in Europe, which is spreading throughout European countries. It can occur in cattle as an acute, a subacute, and a chronic stage.

Bovine besnoitiosis is clinically characterized by the succession of three phases: (i) the initial febrile syndrome with photophobias, epiphora, ocular and nasal discharges, arrest of rumination, anorexia, increased heart and respiratory rates;(ii) the second phase with enlargement of lymph nodes, generalized edema, and hyperesthesia of the skin and; (iii) the third phase, i.e. the chronic form, with scleroderma, hyperkeratosis, hyperpigmentation, and extensive alopecia.