Comparative efficacy of neem (Azadirachta indica) and papaya (Carica papaya) seeds on digestive health of grasscutters (Thryonomys swinderianus): insights into their nutritional potential

Abstract Parasitic infections are a major constraint to grasscutter production, and farmers in Benin commonly use medicinal plants as alternatives to conventional anthelmintics. This study evaluated the comparative effects of neem ( Azadirachta indica ) and papaya ( Carica papaya ) seeds on gastrointestinal parasite shedding in farmed grasscutters. A field survey was conducted on 100 grasscutter farms in the Plateau Department, and fecal samples were examined using qualitative flotation and quantitative McMaster methods. In addition, an experimental trial was conducted with 50 grasscutters allocated to five groups: untreated control, neem at 150 or 200 mg/kg body weight (BW), and papaya at 150 or 200 mg/kg BW. In the surveyed farms, papaya and neem seeds were used by 54% and 46% of farmers, respectively, mainly in powdered form and at doses of 150–200 mg/kg BW. Coprological examinations identified coccidia, Trichuris , Strongyloides , strongyles, and cestodes, with the highest parasite burdens observed for coccidia. Under experimental conditions, parasite oocyst/egg counts decreased following administration of both plant preparations, with lower counts generally observed at 200 mg/kg BW. The descriptive results also indicated a greater reduction with neem than with papaya at the doses tested. These findings support the potential of neem and papaya seeds as locally available plant-based treatments for reducing gastrointestinal parasite shedding in farmed grasscutters. However, the observed differences should be confirmed using appropriate animal-level repeated-measures statistical analyses before recommending a specific dose for field use.