Albendazoles Case Study

In vitro, albendazole-treated groups showed 5.6–73% egg hatch-ing depending on the drug concentration. The egg hatching percentis affected by the drug concentration owing to the fact that the eggsare albendazole susceptible. The inhibitory effect of albendazole onF. gigantica eggs indicates that it can pass the egg shell and stop fur-ther development. At the highest albendazole concentration, thedevelopment was 10%, and the rest of eggs failed to be embry-onated as they stopped at advanced stages of cell division. Twomechanisms of action of BZs against nematode eggs including theinterruption of the embryonation and the failure of hatching weredescribed (Le Jambre, 1976; Boersema, 1983; Weston et al., 1984).The ovicidal activity of BZs such
gigantica eggs to triclabendazole was confirmed by the EHA. Thedifferent concentrations of egg treatments with triclabendazoleshowed 0% development which confirms potential triclabenda-zole effect on Fasciola eggs at the early developmental stages. Thedrug may prevent embryonation by inhibiting initial cell divisionand/or by killing the cells. Accordingly, eggs of triclabendazolegroup showed lysis of the embryo and no further developmentalstages such as morula, eye spot stage or egg containing miracid-ium were detected in this group. The same findings were recordedin susceptible Fasciola treated with triclabendazole (Fairweatheret al., 2012).It is clear from the results that oxyclozanide is a highly effectivecompound for the treatment of Fasciola infected cattle. It showed100% FER by the 2nd week of the treatment. The high efficacy ofoxyclozanide was confirmed in different studies (Walley, 1966; Royand Sukhla 1971; Mooney et al., 2009; Shokier et al.,
Although, in vitro activity of oxyclozanide againstadult Fasciola worms was reported previously (Jeyathilakan et al.,2012). It was surprising to record that oxyclozanide in vitro did notaffect the egg development and egg hatching percentages. Therewas no significant difference in EHA of the control and variousoxyclozanide concentrations. It is of interest to clarify that the abil-ity of drugs to pass through the egg shell and to show its effectdepends mainly on the solubility in the fat layer of the egg shell.Since, oxyclozanide has a hydrophilic nature (Swana, 1999), it maybe not able to pass the fat layer of the egg shell. Consequently, thehatched miracidium showed sluggish movement and it was easy tobe captured beside its empty hatched eggs with open operculum.Praziquantel had no significant effect on either FER or EHA%.Different studies showed failure of human treatment against fasci-oliosis with praziquantel (Farag et al., 1986; Farid et al., 1989; Chai,2013). Such failure may be related to the resistant properties of theF. hepatica tegument. Vacuolization of this layer was observed whenSchistosoma mansoni and Dicrocoelium were treated with prazi-quantel in vitro, but such changes were conspicuously absent