The Effect of the Manure from Sheep Treated with Anthelmintics on Clover (Trifolium pratense)

Abstract

The anthelmintics (regularly administered to livestock to control the infections caused by parasitic worms) and their metabolites formed in treated animals are excreted to the environment. This contamination might have a negative influence on non-target organisms including plants. Our previous studies described the uptake, metabolism, and effects of anthelmintics in plants using in vitro models exposed to anthelmintic drugs in solutions. The present study was performed in clover grown in soil fertilized with manure from sheep treated with the recommended dose of albendazole (ABZ), ivermectin (IVM), or monepantel (MOP). The uptake and metabolism of drugs in clover were monitored for six weeks using UHPLC-MS/MS, and several stress markers (proline accumulation, lipid peroxidation, and antioxidant enzymes activities) were evaluated. The results showed that ABZ and MOP were absorbed, metabolized, and translocated to leaves, while IVM was detected only in the roots. No or minimal drug-response was observed in monitored stress markers, and only a temporary increase of several antioxidative enzymes activities was observed. Overall, manure from sheep treated with anthelmintics does not evoke chronic stress in clover, but it can cause the entry of anthelmintics in other organisms and the food-chain.