Anthelmintic activity of Artemisia annua L. extracts in vitro and the effect of an aqueous extract and artemisinin in sheep naturally infected with gastrointestinal nematodes.

There is no effective natural alternative control for gastrointestinal nematodes (GIN) of small ruminants, with Haemonchus contortus being the most economically important GIN. Despite frequent reports of multidrug-resistant GIN, there is no new commercial anthelmintic to substitute failing ones. Although trematocidal activity of artemisinin analogs has been reported in sheep, neither artemisinin nor its plant source (Artemisia annua) has been evaluated for anthelmintic activity in ruminants. This study evaluated the anthelmintic activity of A. annua crude extracts in vitro and compared the most effective extract with artemisinin in sheep naturally infected with H. contortus. A. annua leaves extracted with water, aqueous 0.1% sodium bicarbonate, dichloromethane, and ethanol were evaluated in vitro by the egg hatch test (EHT) and with the bicarbonate extract only for the larval development test (LDT) using H. contortus. The A. annua water, sodium bicarbonate (SBE), ethanol, and dichloromethane extracts tested in vitro contained 0.3, 0.6, 4.4, and 9.8% of artemisinin, respectively. The sodium bicarbonate extract resulted in the lowest LC99 in the EHT (1.27 µg/mL) and in a LC99 of 23.8 µg/mL in the LDT. Following in vitro results, the SBE (2 g/kg body weight (BW)) and artemisinin (100 mg/kg BW) were evaluated as a single oral dose in naturally infected Santa Inês sheep. Speciation from stool cultures established that 84-91% of GIN were H. contortus, 8.4-15.6 % were Trichostrongylus sp., and 0.3-0.7% were Oesophagostomum sp. Packed-cell volume and eggs per gram (EPG) of feces were used to test treatment efficacy. The SBE tested in vivo contained no artemisinin, but had a high antioxidant capacity of 2,295 µmol of Trolox equivalents/g. Sheep dosed with artemisinin had maximum feces concentrations 24 h after treatment (126.5 µg/g artemisinin), which sharply decreased at 36 h. By day 15, only levamisole-treated sheep had a significant decrease of 97% in EPG. Artemisinin-treated and SBE-treated sheep had nonsignificant EPG reductions of 28 and 19%, respectively, while sheep in infected/untreated group had an average EPG increase of 95%. Sheep treated with artemisinin and A. annua SBE maintained blood hematocrits throughout the experiment, while untreated/infected controls had a significant reduction in hematocrit. This is the first time oral dose of artemisinin and an aqueous extract of A. annua are evaluated as anthelmintic in sheep. Although oral dose of artemisinin and SBE, at single doses, were ineffective natural anthelmintics, artemisinin analogs with better bioavailability than artemisinin should be tested in vivo, through different routes and in multiple doses. The maintenance of hematocrit provided by artemisinin and A. annua extract and the high antioxidant capacity of the latter suggest that they could be combined with commercial anthelmintics to improve the well-being of infected animals and to evaluate potential synergism.

Ethnoveterinary Study of Plant-Based Remedies for Treating Diseases in Small Ruminants in Maputo Province, Mozambique.

Small ruminants, particularly goats and sheep, are key livestock species in Mozambique, and their production is mainly undertaken by families. However, small ruminants are often plagued by diseases that can cause considerable economic damage. In this context, traditional remedies, including various plant species, have been widely used to manage these diseases. The aim of this study was to explore the use of plant-based remedies and other treatments for managing diseases in small ruminants in Maputo Province, Mozambique. Data collection involved conducting interviews with 44 small ruminant breeders across 5 districts in Maputo Province to identify the plants and other remedies commonly used for managing diseases in their animals. We identified a total of 38 plant species belonging to 22 families. Among these plants, four were not identified by their scientific name. The most important plants reported were Cissus quadrangularis, Euphorbia kirkii, and Aloe sp., with Cissus quadrangularis being particularly noteworthy as it was frequently cited for the treatment of wounds. The most commonly cited botanical families were Fabaceae, Euphorbiaceae, and Asphodelaceae. Interestingly, in addition to plant-based remedies, we also identified other nonplant sources of treatment, such as alkaline batteries, which are commonly used to treat wounds in small ruminants. The use of plants for ethnoveterinary purposes remains prevalent in Maputo province, with older breeders serving as the primary custodians of this traditional knowledge. Efforts should be made to document and share the knowledge of these older breeders, ensuring that it is not lost over time. This preservation of ethnoveterinary knowledge can contribute to sustainable livestock management and support the wellbeing of both rural communities and their animals.