Comparative efficacy of chitosan enhancement of quinfamide or toltrazuril alone in an outbreak of coccidiosis in sheep

Quinfamide is an antiprotozoal drug that has almost never been used in veterinary medicine. The only reference of its use in animals derives from its prophylactic administrationto hamsters as preventive measure to re-infection with Eimeria criceti. It has a considerable effect vs. Entamoeba histolytica in humans. A comparative trial of efficacy of quinfamide and toltrazuril alone or quinfamide and toltrazuril combined with chitosan was carried out in a field outbreak ofcoccidiosis (Eimeria ovinoidalis) in fifty sheep two to four month old. Efficacy was assessed individually as the per cent ability. to eliminate coccidian oocysts and also quantifying group performance to each treatment through ANOVA for repeated measurements. Quinfamide alone reached a 31.27% efficacy and 76.74% with chitosan. Toltrazuril efficacy was 61.66% and toltrazuril-chitosan had only 56.81% efficacy. Efficacy of the quinfamide-chitosan combination was statistically superior (P < 0.05) as compared to the other three treatments. Yarious hypothesis as to the manner in which chitosan enhances quinfamide efficacy are discussed.