1997, Number 4
In vitro and in vivo fascioliscide efficary of two chemical compounds in sheep
lbarra VF, García SE, Fernández RM, Vera MY, Castillo BR, Hernández CA
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Language: English/Spanish
References: 16
Page: 291-296
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ABSTRACT
Fascioliscide activity of 6-chloro-5-(1-naphtoxy)-2-methyltiobencimidazol called Alfa and 6-chloro-5-(2- naphtoxy)-2-methyltiobencimidazol called Beta was evaluated under in vitro and in vivo conditions in sheep. In vitro efficacy was determined for both compounds using excisted Fasciola hepatica metacercariae at concentrations of 50, 10, 3.33, 1.11 and 0.37 mg/L. Efficacy was assessed by comparing the survival of the flukes after a four day period of the exposition to the chemicals. Compound Alfa showed an efficacy of 100, 100, 77.5, 0.0 and 0.0%, and compound Beta of 100, 67.5, 1.75, 0.0 and 0.0%, respectively. For the in vivo evaluation, forty five crossbred sheep were used and infected with 150 metacercariae each. Eight weeks after the initial infection, when all animals were positive to Fasciola eggs, the sheep were randomly divided in 5 groups of 9 animals each. Groups 1 and 2 were treated orally with 10 and 15 mg/kg of compound Alfa, respectively. Groups 3 and 4 were dosed orally with 10 and 15 mg/kg of compound Beta, respectively. Group 5 remained as the non-treated control. Two weeks after the treatment, all sheep were euthanized in order to collect and count the flukes in the liver. The efficacy was determined as the percentage of flukes reduced in the treated groups in comparison to the control one. Results showed an efficacy of 80.6% and 86.9% for Groups 1 and 2 respectively, and of 0.0% for Groups 3 and 4, respectively. Measurements of the fluke's length and liver weight did not show any adverse effects attributable to the treatments. It is concluded that under in vitro and in vivo conditions, compound Alfa exerted remarkable efficacy, and compound Beta only showed an acceptable one under the in vitro testing.REFERENCES
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