Determination of the effective dose of an experimental fasciolicide in naturally and experimentally infected cattle

Ibarra, Froylán; Vera, Yolanda; Quiroz, Héctor; Canto, J.A; Castillo, Rafael; Hernández, Ariana; Ochoa, Pedro

doi:10.1016/j.vetpar.2003.12.005

Cited by 22 publications

(10 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…By comparison, a flaky tegument on the adult fluke was observed until 24 h of treatment in a previous study carried out by Rivera et al (2004). Previous in vivo studies have shown that compound alpha is a highly effective fasciolicide, being active against different stages of F. hepatica in sheep and cattle Ibarra et al 2004). In recent studies, McConville (2004) showed that this novel fasciolicide is effective against triclabendazole-resistant flukes from the north of Ireland.…”

Section: Discussionmentioning

confidence: 91%

The effect of the 5-chloro-2-methylthio-6-(1-naphtyloxy)-1H-benzimidazole on the tegument of immature Fasciola hepatica in their natural host

et al. 2005

Self Cite

View full text Add to dashboard Cite

The damage to the tegument of 3-week-old Fasciola hepatica was evaluated by scanning electron microscopy (SEM) following treatment with the 5-chloro-2-methylthio-6-(1-naphtyloxy)-1H-benzimidazole (called compound alpha) in its natural host. For the present study, flukes were raised in pelibuey sheep infected orally with metacercariae of F. hepatica; the parasites were recovered from the liver of the sacrificed sheep after 6, 12 and 24 h of treatment with compound alpha. At 6 h of treatment, the flukes showed some lesions on the ventral surface of the anterior region, such as a swollen tegument and blebs. At 12 h after treatment, the specimens showed structural disorganization and spine loss in the ventral anterior region. The tegument of the flukes treated for 24 h was completely lost in some areas of the ventral surface, leaving an exposed basal lamina. The tegument of immature F. hepatica might be a target organ for compound alpha to exert its fasciolicide effect.

show abstract

Section: Discussionmentioning

confidence: 91%

The effect of the 5-chloro-2-methylthio-6-(1-naphtyloxy)-1H-benzimidazole on the tegument of immature Fasciola hepatica in their natural host

et al. 2005

Self Cite

View full text Add to dashboard Cite

show abstract

“…SO is capable of exerting an effect on the juvenile TCBZresistant F. hepatica. It is uncertain whether this is significant enough to yield an efficacy similar to those reported against a presumably TCBZ-susceptible Mexican isolate (Hernández-Campos et al 2002;Ibarra et al 2004;Vera Montenegro et al 2004). An in vivo study involving Fig.…”

Section: Discussionmentioning

confidence: 99%

Immature triclabendazole-resistant Fasciola hepatica: tegumental responses to in vitro treatment with the sulphoxide metabolite of the experimental fasciolicide compound alpha

et al. 2006

View full text Add to dashboard Cite

Juvenile triclabendazole-resistant liver flukes, Fasciola hepatica, were incubated in vitro with 10 microg/ml of the sulphoxide metabolite of the experimental fasciolicide, compound alpha [5-chloro-2-methylthio-6-(1-naphthyloxy)-1H-benzimidazole], for 6 and 18 h. Following treatment, the specimens were examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and tubulin immunocytochemistry. The SEM results revealed a posterior-directed disruption comprised predominantly of swelling and blebbing of the tegument; these changes were more severe and extensive after the longer 18-h incubation. Along with swelling of the tegument and blebbing, the TEM results also revealed swelling of the mitochondria and basal infolds. A decrease in the number of both T1 and T2 secretory bodies was observed in the syncytium and cytoplasmic connections after the 18-h treatment. The circular muscle bundles were also disrupted, in that the organisation of the muscle fibres was irregular and the total number of muscle fibres was reduced. The immunocytochemical studies revealed no significant disruption to the distribution of tubulin immunoreactivity within the tegumental syncytium, the cytoplasmic connections or the associated tegumental cells. The results indicate that alpha.SO is capable of disrupting the tegument of 4-week-old triclabendazole-resistant liver flukes, though the morphological changes were not associated with any significant differences in tubulin immunostaining.

show abstract

“…Although previous studies on the fasciolicide activity of experimental compound alpha have been reported for sheep (Vera 1994;Ibarra et al 1996Ibarra et al , 1997Ibarra et al , 2000Herna´ndez et al 2002;Rivera et al 2002) and cattle (Vera et al 2003Ibarra et al 2004), nothing is known about its mode of action.…”

Section: Introductionmentioning

confidence: 99%

Tegumental surface changes in adult Fasciola hepatica following treatment in vitro and in vivo with an experimental fasciolicide

et al. 2004

Self Cite

View full text Add to dashboard Cite

Our objective was to determine by scanning electron microscopy the structural changes in the tegument of adult Fasciola hepatica after treatment with 5-chloro-2-methylthio-6-(1-naphtyloxy)-1 H-benzimidazole, called compound alpha, and its active metabolite sulphoxide, under in vitro and in vivo conditions. For the in vitro studies, flukes from sheep were exposed to 40 mg/l of compound alpha-sulphoxide over different incubation times. Flukes for the in vivo studies were raised in sheep treated orally with compound alpha and killed at different times post-treatment. Non-treated controls were included for each time of incubation. The results showed lesions after 6 h of treatment, such as swelling and furrows. At 12 h, the spines appeared to be surrounded by the tegument. At 24 h the tegument in some areas showed an exposed basal lamina. These changes became more severe as the incubation periods of the treated flukes increased. Compound alpha exerts a significant effect on the tegument of F. hepatica.

show abstract

Determination of the effective dose of an experimental fasciolicide in naturally and experimentally infected cattle

Cited by 22 publications

References 12 publications

The effect of the 5-chloro-2-methylthio-6-(1-naphtyloxy)-1H-benzimidazole on the tegument of immature Fasciola hepatica in their natural host

The effect of the 5-chloro-2-methylthio-6-(1-naphtyloxy)-1H-benzimidazole on the tegument of immature Fasciola hepatica in their natural host

Immature triclabendazole-resistant Fasciola hepatica: tegumental responses to in vitro treatment with the sulphoxide metabolite of the experimental fasciolicide compound alpha

Tegumental surface changes in adult Fasciola hepatica following treatment in vitro and in vivo with an experimental fasciolicide

Contact Info

Product

Resources

About