Effect of select media supplements on motility and development of Eimeria nieschulzi in vitro.

A technique was developed to examine the effects of exogenous substances on apicomplexan sporozoite motility in vitro. Sporozoites of Eimeria nieschulzi were placed in the top compartments of blind well chemotactic chambers and separated from potential chemoattractant/chemokinetic agents by 8.0-microns pore size Millipore filters. After 3-hr incubations, the number of sporozoites migrating through the filters was assessed using a hemacytometer. Results revealed that several substances, especially albumin and fetuin, enhanced motility of coccidial sporozoites. Cell culture assays supported these data, with higher numbers of parasites found in cultures supplemented with albumin and/or fetuin.