Potential New Therapeutic Approaches Based on Punica granatum Fruits Compared to Synthetic Anthelmintics for the Sustainable Control of Gastrointestinal Nematodes in Sheep

SIMPLE SUMMARY: The spread of helminths resistant to the most common classes of anthelmintic drugs in sheep and the presence of drug residues in the environment has prompted research to find sustainable alternative solutions for gastrointestinal nematodes control. This study reports the results of in vivo studies on the efficacy of an aqueous Punica granatum-based macerate, used in southern Italy for the control of gastrointestinal nematodes in sheep. The anthelmintic efficacy was evaluated in parallel in sheep infected with gastrointestinal nematodes, using, as a positive control, the treatment with Ivermectin and Albendazole. The results of the study show a good anthelmintic efficacy, suggesting the use of this ethnoveterinary macerate as an alternative and sustainable therapeutical remedy for the helminthiasis control in the sheep. ABSTRACT: Parasites, in particular, gastrointestinal nematodes (GINs) represent one of the main burdens affecting small ruminant farming and pose a serious threat to their health, welfare, productivity, and reproduction. The correct management of animals and the correct use of anthelmintic drugs are the pillars of the GIN control programs for small ruminants. However, globally due to the indiscriminate use of synthetic anthelmintics, there is a significant increase in anthelmintic resistance phenomena to one or more classes of drugs. Even if such a problem never represented a serious threat in southern Italy because of the favourable environmental conditions and because of the good farm management, the phenomenon is actually showing a steep increasing trend and requires alternative treatment measures and constant monitoring. The use of phytotherapies is considered a valuable alternative approach for GIN control in small ruminants and could help with reducing the amount of synthetic drugs used and the forthcoming anthelmintic resistance. From this perspective, the Calabria territory offers a wide number of plants with anthelmintic efficacy that could be helpful for this purpose. The aim of this study was to evaluate the anthelmintic efficacy of aqueous pomegranate (Punica granatum L.) macerate compared to the treatment with Ivermectin and Albendazole in sheep naturally infected with GINs. The pomegranate macerate derives from the ethnoveterinary knowledge of the Calabria region, Southern Italy. The anthelmintic efficacy was evaluated according to the faecal egg count reduction test (FECRt) using the FLOTAC techniques in two sheep farms in Southern Italy. The FECR was calculated from individual samples using the formula FECR = 100 × (1 − [T2/C2]). The treatment with Albendazole in the first farm showed an efficacy of 99.8% after 14 days and 94.8% after 21 days, while the treatment with Ivermectin in the second farm showed an efficacy of 99.9% after 14 days and 96.5% after 21 days of treatment. The pomegranate macerate, in both farms, showed a value of efficacy of around 50% from day 7 to day 21 after the treatment. Previous studies highlighted the presence of gallic acid as the main component in the pomegranate macerate, and its efficacy in nematode control has been as well previously demonstrated in other plant extracts. This in vivo study demonstrated the unequivocal efficacy of plant macerate in easily reducing 50% of the number of GIN eggs in sheep faeces. These results, obtained without the use of synthetic anthelmintics, indicate the use of green veterinary pharmacology as a sustainable alternative to the use of synthetic drugs to reduce the increase in drug resistance phenomena and the environmental impact.