INVESTIGADORES
ALVAREZ Luis Ignacio
artículos
Título:
Comparative assessment of albendazole and triclabendazole ovicidal activity on Fasciola hepatica eggs
Autor/es:
ALVAREZ, L.; MORENO, G.; MORENO, L.; CEBALLOS, L.; SHAW, L.; FAIRWEATHER, I.; LANUSSE, C.
Revista:
VETERINARY PARASITOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2009 vol. 164 p. 211 - 216
ISSN:
0304-4017
Resumen:
The
benzimidazole compounds albendazole (ABZ) and triclabendazole (TCBZ) are both
effective against Fasciola hepatica, although ABZ is only effective
against adult flukes. Additionally, ABZ is a broad-spectrum nematodicidal
compound with well-known ovicidal activity. However, no data on the ovicidal effect
of TCBZ against F. hepatica eggs are available. The work reported here
evaluated the comparative ovicidal effect of ABZ, TCBZ and their sulphoxide
metabolites on F. hepatica eggs recovered from bile of sheep
artificially infected with either a TCBZ-susceptible (Cullompton) or a TCBZ-resistant
(Sligo) isolate of F. hepatica. Additionally,
the effects of different non-flukicidal
methylcarbamate benzimidazole compounds on the hatching of F. hepatica
eggs were evaluated. Eggs (500 eggs/ml, n= 4) were incubated
for 12 h either with TCBZ, TCBZ sulphoxide (TCBZ.SO), ABZ (5, 10 and 20 nmol/mL)
or without drug (untreated control) (Experiment 1). Additionally, the effect on
egg hatchability of TCBZ and TCBZ.SO (5 nmol/mL) was examined after a long
exposure to drug (15 days) (Experiment 2). Furthermore, the ovicidal effect of
ABZ and ABZ.SO at different concentrations (5, 1, 0.5, 0.1and 0.05 nmol/mL) (Experiment
3), and the effect of fenbendazole (FBZ), oxfendazole (OFZ), mebendazole (MBZ),
flubendazole (FLBZ) (5 nmol/mL) and reduced-FLBZ (R-FLBZ) (2 µg/mL) on fluke
eggs, were evaluated after a 12-h exposure (Experiment 4). Egg hatch was assessed
by direct microscopic observation after incubation at 25o C for 15
days. In experiment 1, TCBZ and TCBZ.SO did not affect egg hatch after a 12-h
incubation. A similar result was
obtained after a much longer drug exposure (15 days) (Experiment 2). However, a
significant (P<0.05) inhibition of egg hatch was observed in ABZ- and ABZ.SO-incubated
eggs (Experiments 1 and 3). Additionally, the non-flukicidal compounds
(Experiment 4) affected egg hatchability, particularly FLBZ and R-FLBZ. In conclusion, ABZ and ABZ.SO had a clear
inhibitory effect on egg development of F. hepatica. However, the most
extensively used flukicidal compound, TCBZ, and its main sulphoxide metabolite,
did not affect egg hatch, even in TCBZ-susceptible flukes.