In vivo a ssessment of Closantel ovicidal activity in Fasciola hepatica eggs

SOLANA, MARÍA VICTORIA; SCARCELLA, SILVANA; MIRANDA-MIRANDA ESTEFAN; SOLANA, HUGO DANIEL

Congreso; 13 th INTERNATIONAL CONGRESS OF PARASITOLOGY; 2014

BACKGROUND: Fasciolasis is a zoonotic parasitic disease caused by Fasciola hepatica. Closantel is a flukicide and has been shown to have an efficacy in vivo e in vitro against mature and immature stages, does not exhibitovicidal activity in vitro and the ovicidal effects in vivo at present are undetermined. Egg hatch assay (EHA) is a laboratory tool used to determine a given parasite´s resistance to extant drug therapy remains a safe and reliable technique. In the present work the EHA was used to evaluate in vivo the ovicidal activity of Closantel on fluke eggs. METHODS: Sheep parasitized with liver flukes (Cullompton strain) were treated with Closantel (10 mg/kg bw) (oral and subcutaneous) stunned and exsanguinated at 12, 24, y 36 hs. Post treatment (pt).  F. hepatica eggs were collected from bile. Eggs obtained of sheep without treatment were used as control. After a period of incubation (25 °C, 15 days in dark environment), hatching was induced for two hours of exposure to light, quenched with the addition of formalin. Hatching was assessed sorting the eggs into two groups: embryonated (E) and unembryonated (U). The test (n= 3) wasexpressed as percentage of total eggsanalyzed. RESULTS: The result obtained for control was 89,5% ± 2,12 for (E) and 10,5% ± 2,12 (U). The average of both ways of administration (without significant differences among them) at 12 h pt was 84,5% ± 0,71 (E) and 15,5% ± 0,71 (U); 24 h pt was 86,75 ± 3,18 (E) and 12,75% ± 3,18 (U) and 36 h pt was 32,5% ± 3,54 (E) and 67,5%± 3,54 (U). CONCLUSIONS: Our results suggest that Closantel affect in vivo the normal development of the eggs. As one of the first effects, this drug affects the performance of the trematode?s reproductive physiology.