Livestock play a significant role in livelihoods and the economies of developing countries (Herrero et al., 2013; Hatab et al., 2019). In DR Congo, small livestock production systems are primordial for meat production and to generate income (Wasso et al., 2018; Klapwijk et al., 2020). In Haut-Katanga province, in rural or peri-urban contexts, animal raising is a familial activity, that involves a small number of animals per family. The most common species are poultry (chicken and ducks), goats and sometimes one or two pigs, usually free roaming (Ngona, 2008; Kalenga et al., 2015). Families do not spend much time or money on their livestock: this certainly explains why goats are so widespread and why it plays an important socio-economic role for meat production and to generate income. These livestock keeping are carried out without adequate veterinary advice and with little or no knowledge of goat diseases. In addition, livestock keepers have little access to medicines (Gemeda et al., 2020) and many treat symptoms of disease with herbal remedies. Gastrointestinal parasite (GIP) infection remains one of the main health (Mpofu et al., 2020) and production constraints of goats as they cause severe injuries to infected animals and significant losses in farming production worldwide (Zvinorova et al., 2016).

A survey has already been conducted in rural area in the regions of Kamina and Kaniama (600 km northwest of Lubumbashi, DR Congo) to identify traditional herbal remedies used in the control of gastrointestinal disorders in ruminants (Okombe et al., 2014a). This study revealed that livestock keepers treat when they observe direct signs (presence of worms in feces) or indirect signs in their goats (rough hair coat, loss of weight or appetite, distended abdomen or diarrhea). From this study, the root bark powder of Oldfieldia dactylophylla (Welw. Ex Oliv.) J. Leonard (misidentified as Vitex thomasii De Wild) was the most widely used by farmers. However, little is known about the ethnoveterinary (EV) use of medicinal plants to control GIP infections in goats in the province of Haut-Katanga, which is characterized by different climatic conditions and floristic diversity from the aforementioned regions (Meerts, 2016).

Through a survey of goat farmers who treat their animals with herbal remedies that they make themselves, the objective of the study was to identify the plants used to make these remedies and to verify whether the literature documents their therapeutic usage and/or effectiveness. This information is needed to collect data on EV practices and to consider efficacy studies of plants that are used in field. If, in the long run, studies prove the effectiveness of these therapeutic uses, it is an opportunity for Congolese herders who do not have easy access to drug treatments.

The present study identified 27 medicinal plants that are used by goat keepers in the Haut-Katanga province to treat signs of GIP infections in goats. From the identified medicinal plant (Table 2), Fabaceae was the most common plant family reported, followed by Lamiaceae. In agreement with our study, these botanical families have previously been reported in this region as the dominant plant families used in traditional medications (Bakari et al., 2017; Chiribagula et al., 2017). This might be correlated with the abundance of species belonging to these families in the study area.

Of the cited species, five of them, belonging to the family of Picrodendraceae (O. dactylophylla) and Lamiaceae (V. doniana, V. fischeri, V. madiensis and V. mombassae), were considerably more used. The frequency of their uses could in fact be related to its effectiveness as a remedy, to its availability in the study area (Ahmad et al., 2014; Amjad et al., 2017) or to taxonomic confusions. These plants are all morphologically characterized by their palmately compound leaves. The substitution observed in identifying these species may result in diminished pharmacological activity or even intoxications (Yamani et al., 2015; Cruz De Oliveira Costa et al., 2017; Ng et al., 2019) and may also cause adverse reactions that range from mild to life-threatening (Basak et al., 2019).

Among the different plant parts, the roots are most frequently used by informants for the treatment of worm infections in goats, followed by leaves. Yirga et al. (2012) reported that harvests involving roots, rhizomes, bulb, bark, stem or whole plant have a serious threat on the survival of the plant in its habitat; by contrast, the collection of leaves poses no significant threat to the survival of plants (Boadu and Asase, 2017). To foster sustainability, keepers could be encouraged to propagate the most useful trees or to concentrate on medicinally exploitable leaves, provided that only a reasonable amount of leaves is harvested (Canter et al., 2005). Such a management of resources would reduce eventual threats on interesting plant species. But the limited knowledge of tree species importance and the lack of appropriate propagation techniques remain major constraints in exploiting the domestication potential of medicinal plants (Amri and Kisangau, 2012). In the Haut-Katanga province, our data indicate that most of plants used in EV treatments are collected from the wild. This can be explained by the fact that keepers practice extensive farming in nature, far from cities and markets, and so have an easy access to collect plants in the wild.

All the cited remedies were monotherapies, i.e. based on preparations from a single plant; this may be related to previous experiences of keepers (Otieno et al., 2008) with plant species so efficient that they do not need additional constituents. But this finding markedly contrasts with previous ethnopharmacological study (Okombe et al., 2014a) in Kamina, a more remote Katanga region in which a series of multi-herbal recipes were reported. Maphosa and Masika (2010) reported that some herbalists are aware of the poisonous nature of certain recipes when it comes to mixing herbs; they are thus content with remedies prepared from a single plant. It is probable that the use of single or multi-plant recipes could be directly linked with the floristic diversity in the different study areas, a richer flora giving easier access to a diversity of plants and so to the possibility of testing, collecting and mixing species. In the province of Haut-Katanga, Meerts (2016) effectively observed markedly different phytogeographic and taxonomic assemblages in the three most important types of woody vegetation.

Similar to findings of Okombe et al. (2014a), the most common preparations of EV remedies include maceration and decoction in water for oral administration. Although keepers can use different routes of administration (Hilou et al., 2014; Okombe et al., 2014a, b), most of the treatments cited here were administered orally by drenching prepared remedy to the sick animal, by leaving the plants permanently in the drinker for some days or by mixing plant powder with food. The predominance of the oral route in the administration of treatments can be explained by the ease of administration and by the localization of the major symptoms observed; indeed, the oral route is by far the most common for administrating drugs intended to treat the gastrointestinal tract (Hua, 2020).

The dosage is far from standardized and is stated to depend on the experience of healers; this is generally the case in traditional medicine as exemplified previous ethnobotanical research in the study area (Okombe et al., 2014a, b).

The success of a treatment depends on many factors, including a correct diagnosis of the disease. This study indicates that goat keepers identify GIP infections from clinical signs (Table 2). Indeed, the definitive diagnosis of the disease is a major problem encountered by livestock keepers, leading them to rely solely on clinical signs (Cabaret et al., 2009; Fitzpatrick, 2013). These infections can lead to reduced primary digestion, decreased gastric secretions, dyspepsia, loss of plasma proteins, submandibular edema and blood loss (Craig, 2018; Vande Velde et al., 2018; Tufa et al., 2019); in severe cases, these symptoms can lead to death. Some of these clinical observations (presence of worms in stools, diarrhea, reduced growth, weight loss, anorexia, hypertrophy of mucosa) are indeed typical and recognizable signs. But it should be noted that many of the observed signs are common to several parasitic, bacterial or viral diseases. Although keepers stated that their experience guides the choice of administered “anthelmintic” treatment, the data we could collect were not precise enough to allow any distinction among cited plants.

Our results showed that the participants largely had their families as a source of traditional therapeutic knowledge. For this reason, Yirga et al. (2012) report that in some regions of the world, the transfer of knowledge about medicinal plants is done only from fathers to their first son or to another male child who could keep the secret; this could be the cause of the increase in the number of male livestock keepers. Elderly keepers and non-educated (Table 1) have more knowledge on medicinal plants and their uses, due to long direct contact with plant resources.

Literature data showed that some of the most cited plants, used by the goat keepers against GIP infection symptoms, have been reported to possess anthelmintic activities and some active chemical constituents have been identified. However, these properties have not yet been sufficiently explored for V. fischeri and V. mombassae. This is clearly an area that needs further investigation to validate the traditional use and to develop an eventual improved formulation that could be recommended as anthelmintic.

This study suggests that goat keepers in three territories of the Haut-Katanga province make use of ethnoveterinary knowledge and practices. The substitution or confusion observed in the identification of species is an aspect that warrants partcular attention as this may impact the expected pharmacological properties. It is also imperative to train farmers in correct propagation techniques to encourage the domestication of valuable and endangered medicinal lignous plants. This will create new opportunities for local people, providing alternative income and reducing pressure on the wild species population. Therefore, significant research into the chemical and biological properties of these lowly explored plants is absolutely needed to determine their anthelmintic efficacy and define their exact mechanism of action that could become important for the development of new anthelmintic drugs.