Anthelmintic evaluation of selected phytochemicals in dairy ewes

In this dissertation we showed thein vitroandin vivoanthelmintic activity of selected plant extracts and secondary metabolites against gastrointestinal nematodes and their effects on Sarda dairy ewes. The first chapter reviewed the effects of gastrointestinal nematodes and lungworms on the health status and welfare of small ruminants and the strategies to control nematode infestations. Moreover, the anthelmintic properties of the plant extracts are illustrated. The second chapter reported thein vitroanthelmintic activity ofRuta chalepensisL. extracts and of selected phytochemicals against gastrointestinal nematodes and lungworms of sheep. Especially,Ruta chalepensisL. methanol extract and 2-undecanone showed the highest nematicidal activity with an EC50/96h= 0.10 mg/mL and EC50/24h= 0.88 mg/mL, respectively. The data revealedin vitrodose-dependent anthelmintic activity. In the third chapter we reported the experiment where increasing doses of furfural and 2-hydroxybenzaldehyde were orally administered to Sarda dairy ewes. These phytochemicals and their metabolites were not detected in milk, urine and faecal samples. Moreover, the ewe blood parameters were within the normal range. In the fourth chapter we reported that a single oral dose of furfural, 2-hydroxybenzaldehyde, 2-undecanone and albendazole was administered in sheep. The compounds and their metabolites were not detected in milk with the exception of albendazole sulfoxide a known metabolite of albendazole. Therefore, no negative effects were observed in animals treated with these compounds. With regard to anthelmintic activity, the furfural, 2-hydroxybenzaldehyde, 2-undecanone groups showed the lowest activity if compared with albendazole. In the future, we will optimise the dosage and the mode of action of furfural, 2-hydroxybenzaldehyde and 2-undecanone.