Ethnoveterinary medicines in four districts of Jimma zone, Ethiopia: cross sectional survey for plant species and mode of use

Ethnoveterinary medicine, defined as the “application of veterinary folk knowledge, theory and practice to treat ailments of livestock,” has been the focus of several studies in the last few decades [1]. The current rich and resourceful traditional knowledge of ethnoveterinary have been transferred to generations by words of mouth only [2]. A large number of farmers rely on a range of ethnoveterinary knowledge to keep their livestock healthy and have been used for preventing and treating livestock ailments for several generations. Diversity of plant species which have pharmacological activities were identified so far and the active ingredients are extracted mainly from the root, stem, and leaf parts that processed to administer through appropriate routes [3]. They traditionally learned to diagnose clinical features of endemic animal diseases by the use of traditional equipments like bamboo syringes, stone tourniquets, animal horn products, squashing with their hands, and wood forceps to determine dosage, and prepare remedies from local medicinal plants. Treatment by contemporary veterinary medicine has, in these days, been out of the reach of the ordinary farmers often due to high cost of drugs and none coverage [4, 5]. The farmers have subsequently explored many ethno-botanical products in treating livestock diseases [6]. With a view of those traditional practices, the world health organization (WHO) declared the important roles of ethno-botanical products in veterinary and human medicines in the Alma-Ata proclamation in 1978. Additionally, WHO also stated that the use of these natural products in control of animal and human diseases are considerably effective [7]. In 1996, the American Veterinary Medicine Association also officially stated that botanical products are safely used in compliment of National Intervention Program of livestock diseases [8].

Many studies assured that farmers and pastoralists in several countries such in West Java, Indonesia [9], Mexico, Nigeria [10], Ormaland, Kenya [11], Zimbabwe [12], South Africa [13], China [14], Pakistan [15] and India [16] widely use medicinal plants in conservation of the health of livestock. Similarly, across all regions of Ethiopia since long time have been using ethnoveterinary knowledge to treat livestock disease for thousands of generations [4, 5, 17–22]. It is estimated that up to 90% of current livestock diseases are managed through the use of traditional medicines [23]. The livestock production in Ethiopia has been beset by many problems which mainly include poor nutrition, poor management and diseases; whilst in recent times livestock diseases cause more economic losses [4].

Practices in ethnoveterinary medicine solely depend on the collective memories of just a few practitioners within communities, being it is not such a common knowledge for everybody. However, such increase in ethnoveterinary knowledge, which has been transferred verbally from one generation to the next from immemorial time, is currently in a danger of being lost whenever a traditional veterinary practitioner passes away without conveying his traditional medicinal plants knowledge [24].

Despite these facts, very little efforts have so far been made to reverse the trends and promote skills effectively throughout modern time courses. Few ethnoveterinary surveys have been conducted in Ethiopia, such as Borena pastoralists [5], different studies in two localities of Tigray [4, 20], Fentale, Esternshowa [21], Boosat, Welenchetti [17], Bale Mountains National Park [18], and Gilgel Ghibe [19], but only Goma district in Jimma zone [25] to document the well known ethno-botanical products used in animal health care practices. Therefore, this study was conducted to identify and scientifically document plants applied in ethnoveterinary practices along with livestock ailments treated by farmers in four districts of Jimma zone.

In this scientific paper, we presented an inventory property and the mode of use of plants derivatives to treat livestock ailments in four districts of Jimma zone, Ethiopia. The study showed that majority of the traditional healers were above 48 years since it is very difficult to disclose their traditional medicinal information, which they considered their indigenous knowledge as a professional secret, only to be passed orally to their eldest son in their old age.

The gender distributions of medicinal plant knowledge showed most of the traditional healers are males (94.05%) as there were very few female (5.95%) practitioners. The very good reason why greater numbers of traditional practitioner are male might be related with the local tradition of restricting such practices mostly to males whereas females were not allowed to be involved in outdoor activities but remain home as they look after babies and carry out domestic activities. It was also observed that females’ knowledge in medicinal plants is by far limited to plants, which are found in domestic environments like Zingiber officinale Roscoe, Ocimum lamiifolium Benth., Nicotiana tabacum L., Lepidium sativum L. and Allium sativum. Additional reason was being transfer of medicinal plant knowledge from fathers only to their first son or other male child that could keep the secret. Yirga et al. [28] also reported consistent result in which 100% practitioners were males and the study conducted in china by Shen et al. also reported consistent finding in which majority (56.7%) of traditional practitioners were males [14].

In comparison of educational status, non-educated informants handled much knowledge of traditional medicine whereas educated informants had low knowledge of traditional medicine, which is an indicative of impact of modern education.

In general, the present study identified 74 medicinal plants that have been endemically used to treat 22 different types of livestock diseases by traditional practitioners in Jimma Zone. In similar study that carried out in Southern Ethiopia among Borena pastoralists, 43 ethnoveterinary plants were documented scientifically to national ethno-botanists level [5]. Likewise, another report by Giday et al.[4] of study in Ofla and Raya-Azebo woredas, South Tigray also showed that they identified and scientifically documented 83 plant species for treating 37 types of livestock ailments. In same geographical region south Tigray, Seharti-Samre district, twenty two species of ethno-botanies were identified by Yirga et al. [20] and scientifically recognized by Ethiopian botanist that have many medicinal roles to 18 livestock ailments. Overall, these reviews of past literature show that naturally our country, Ethiopia, endowed with plenty of medicinal plants fairly distributed throughout its regions.

Our observation also agreed with medicinal plant species found elsewhere in the various study districts that are given for different diseases or have similar medicinal purposes in those regions of Ethiopia and in Africa. Among the total of Seventy-four medicinal plant species investigated in this study, 15 species in Akaki district of eastern Shewa by Bekele et al.[29]; 13 species in Gimbi district of Eastern Wellega by Megersa [30]; 8 species in Western Wellega by Tolossa [31]; 9 species in Goma district of Jimma zone by Behailu [25]; 8 species in Wonago district of SNNPR by Mesfin et al. [32], 10 species in Chelya district of Western Shewa by Amenu E. [33], 7 species in Seharti-Samre district of southern Tigray by Yirga et al. [20], 3 species in South Omo of SNNPR by Tolesa et al. [34] and 7 species in Kenya [11] were documented. All these suggest that traditional ethnoveterinary knowledge widely used in Ethiopia and there might be increases inclination of people to depend on such practices because it is considered equivalently effective to modern cares and easily available in their domestic environments.

With regard to data from the medicinal plant classes studied (Tables 1 and 2); Asteraceae was the most common plant family reported followed by Cucurbitaceae and Solanaceae. Those findings were in agreement with report by Yineger et al.[18] in Bale Mountains National Park in which Asteraceae as the highest, followed by Solanaceae and Fabaceae. Similarly, other researchers also stated that diversified classes of medicinal plants were identified from Asteraceae family [32].

Predominant distribution of ethno-botanical medications was commonly sought from wild sources but few were domestically cultivated as well as the remaining usually marketed. What draws greater attentions, the majority of farmers depend on wild environments where the plants are naturally grown rather than domestication of them due to beliefs about medications and promote secrecy behind such practices. It was also found from the present study area that some traditional healers did not have interest to domesticate the plant species used to treat specific ailments. The plants which were found in domestic area and had pharmacological activity are not purposely cultivated for medicinal value, but mainly for purposes like food, fence, spice and so forth. A comparable finding about distributions of the medicinal plants was also reported in many Ethiopia, African countries and Asian countries [14, 20, 25, 31].

Among the medicinal plants found, type of them analysis showed that trees were primarily involved, followed by shrubs. The very good reason why these two plant types are the leading in medicinal practices might be attributed to their easily occurrence in the immediate environments with high level of abundance. Also the presence of more medicinal trees and shrubs in the findings indicated the fact that there might be tree and shrub rich forest resources in the area in the past. These facts might be influenced the indigenous knowledge of the local people in the area and invented as a result of frequent trial and errors. The finding of trees predominantly in medicinal purposes than other plant types for the treatment of livestock ailments is in line with research in Gimbi district, West Wellega [33]. In contrast, Kebu et al.[21] reported that shrubs took the leading, which accounted for nearly 45% of the medicinal plants used by Kereyu pastoralists.

Data from plant parts showed the most common phytochemical substances for medicinal purposes were frequently extracted from leaves part of ethno-botanies followed by roots and seeds, respectively. Many reports in different geographical regions of Ethiopia also consistently indicated that plant parts involved in traditional remedies formulation in this study area, almost having proportional rate of usage in Orissa, India and Faisalabad, Pakistan [4, 15, 19, 20, 22, 35]. Different from our findings, a number of researchers reported that root parts were frequently involved in preparation of pharmacological substances to cure various livestock diseases occurring endemically [17, 18, 21, 33, 36]. The good reason why plant leaves most frequently used in extraction of pharmacologically active ingredients to treat diseases of livestock was, indeed, due to the fact that leaves contain many metabolites with characteristic anti-illness effects. In ecological perspective, herbal preparation that involves roots, rhizomes, bulbs, barks, stems or whole parts have effects on the survival of the mother plants [18]. Harvesting of leaves compared to harvesting of roots has a less negative influence on the survival and continuity of useful medicinal plants and hence does not affect sustainable utilization of the plants.

Analysis of mode of administration showed oral route was the most common mode of administration followed by topical and nasal route, respectively. Those findings were almost consistent with studies within different regions in Ethiopia. For instance, Teshale et al.[5] reported most of medicinal plants used by Borena pastoralists were administered through oral route followed by dermal route. Kebu et al.[21] in their study in Fentalle (Eastern Shewa) reported that greater than half of remedies studied were administered orally. A few studies, however, reported predominantly the dermal application of cultural remedies and to lesser extent oral administration [20]. They were chosen best route of administration, both oral and topical routes, because they considered permitting rapid physiological reaction with the pathogens and increasing the curative power of the medicines.

Similar to findings of previous research, preparation and application for different types of illnesses included concoction, decoction and infusion [14, 36]. The most common dosage form was concoction in water followed by decoction. That was because these processes produce complete extraction of active ingredients. Plant medicines were processed mostly as mixture of two or more species in this investigation. Analysis of poly herbal prescription (Table 1) suggested that, the average number of plant species used for preparation of the remedies per prescription was found to be 3.47 (66 plant species involved in 19 prescriptions). That was due to the belief of the healers that the mixing of two or more plants has synergistic effects on the illnesses. For instance, the highest number in the poly herbal medications with admixture of two or more of them was prescribed against blackleg, the commonest disease in the study area. That observation was in agreement with the findings of study in Gimbi district, West Wellega [31] and three Nu villages of China [14]. That findings were far contrasting when compared with results of investigation in two domestic states of Ethiopia [5, 21], who reported that the use of multiple plants and plant parts for single animal health problem was rare. In ways of drug formulation, majority of the farmers depend on water medium as a vehicling system, which might be due to its easily availability and universal solvent. Also additive substances like human urine, food, kerosene oil, soap and common salt were mixed in the herbal remedy preparations. The additives were used to modify flavor so that mask the taste of the medicine and ensure to intake adequate dosage of medication, which also documented in similar study in regions of Ethiopia [5, 19, 25, 30, 31, 33].

Some study participants responded that restrictions are obligatory when the animal takes remedy for blackleg lest some factors always slow physiological reaction and affect the curative power of remedies. However, according to the study conducted by Tolossa in Gimbi district, no such restriction was found out in the medication of livestock [31].

Some of the medicinal plants were very popular and used widely in our study area. For instance, Croton macrostachyus Del, Nicotiana tabacum L. and Olea capensis L.Subsp. macrocarpa (C.H. Wright) I.Verd. observed as typical medicinal plants that were very common in the area with higher level of efficacy. The wide use of these medicinal plants resulted from the occurrence of the diseases to be treated by them was high why the medicinal value of the plants become a very common practices and the secrecy behind remain disclosed to every persons.

Croton macrostachyus Del reported in the present study for the treatment of bloat and skin lesion in cattle and also reported for the same purpose in other studies [5, 25, 29], indicating medicinal popularity of this species. Yirga et al.[28], likewise, investigated the use of this plant in combination with Corchors depressus for the treatment of bloat in livestock. But Tolesa E in Gimbi district of Western Wellega reported the use of the plant for the treatment of rabies [31]. Similarly, Amenu E. reported from Chelya district of Western Shewa the use of this plant for infection (mix of leaf of Croton macrostachyus and bulb of Allium sativum) and scabies (mix of leaf of Croton macrostachyus with Brucea antidysenterica). Such kind of wide spread use of a given plant species might indicate the pharmacological effectiveness [33]. Nicotina tobacum L. was the most frequently used plant for black leg and snake bite in the present study that also agreed with study conducted in West Wellega, Gimbi district [31].The plant product also has been used against control of ectoparasites such as leeches and ticks [4, 25, 29, 34, 37]. Tabuti et al. [36] in Uganda suggested the use of this plant for ophthalmic problems. However, Olea capensis L.Subsp. macrocarpa (C.H. Wright) I.Verd. was completely novel use in our study area and never ever reported in other similar investigations where the plant considered occurring endemically.

Vernonia amygdalina Del. was the most frequently used plant for removal of retained placenta around the study districts and also suggested in report from western Wellega region of Ethiopia and Uganda [30, 36]. Ndi [38] recognized the use of this plant for antihelmenthiasis activity in Cameroon. The use of Justicia schimperiana (Hochst.ex Nees) T. Anders for treatment of black leg was already reported by many researchers [4, 31, 33].

Senna didymobotrya (Fresen.) Irwin & Barneby involved in treatment of venom of snake bite in livestock was already reported by Tolossa E [31]. Citrus aurantifolia (Christm.) for treatment of poultry disease in our study was reported by Monteiro et al. for the same purpose [39] and disagreed with report from study in North Western Ethiopia in which the plant products were commonly used for controlling leech infestation in livestock [40]. Calpurnia aurea (Aiton) Benth. for ectoparasites and black leg in our finding has also been previously documented in some areas of Ethiopia [25, 30–34]. Zingiber officinale Roscoe for treatment of eye inflammation in our investigation that was consistently reported in previous studies [20, 41]. In contrast to these findings, this plant was traditionally used against constipation in study of India [42] and black leg infections in study of Western Wellega [31]. Lepidus sativum L.was reported to be used against black leg that holds true in our observation [31]. Verbascum sinaiticum Benth. was remedy of first choice in treatment for skin infection in our study. This plant in three reports of study in Ethiopia stated its wide spread use in treatment of leech infestation, worm and trypanosomiasis[4, 31, 43]. The pharmacological activity of Phytolacca dodecandra L. in foot and mouth disease [31], in anthrax [4, 43], in black leg [4] and in trypanosomiasis[43] were agreeably reported but only used against foot and mouth diseases (FMD) in this finding.

New findings of this investigation that involved in pharmacological activity against livestock diseases include plant species such as Fagaropsis angoleusis, Allophylus macrobotryls Gilg., Pentas schimperiana, Olea capensis L.Subsp. macrocarpa (C.H. Wright) I.Verd., Ekebergia capensis Sparm., Leonotiso cymifolia, Gouania longispicata Engl., Acmella caulirhiza Del., Euphorbia schimperiana Scheele and Clausena anisata Benth. The medicinal activity of these plants are novel findings that only known in this area for such purpose.

As suggested by our study half of the respondents stated their best choice as either TVM or MVM for animal treatment which was determined based on type of ailments. Additionally, TVM was best choice for some of respondents in animal health problems. However, majority of the respondents suggested that MVM is their first choice for livestock ailments. As a result, it was concluded that based on these findings of our study both treatment systems had higher values in health care of livestock in the area, like observation in Faisalabad district of Pakistan [15].

This study suggested that farmers of four districts of Jimma zone have sound ethnoveterinary knowledge and practices. In our investigational activity, efforts made to document ethnoveterinary knowledge, practices and plants of veterinary importance. Accordingly, the study enabled us to document about 74 species of medicinal plants that have been used against 22 types of livestock diseases in study districts, so far. In general, plant parts, methods of preparation, and source of such plants were also elaboratively presented. Wild plants of veterinary importance may not be well protected, as a result can be lost due to deforestation and over grazing as they are not individual farmer’s properties. Therefore, the healers with consultation of governmental responsible ethno-botanist bodies should take care not to eradicate the medicinal plant species altogether. Awareness creation among the traditional healers and community at large are important measures to preserve their indigenous medicinal plant species [44]. Poly ethno-botanical prescriptions should be further evaluated for possible active ingredient interactions and what clinical relevancies associated with them. These indigenous knowledge and practices of four district communities should be supplemented by scientific methods to evaluate the safety, efficacy and dosage of the common medicinal plants through phytochemical and antimicrobial experimentation to determine appropriate mode of delivery, drug development and dosage in pharmacological laboratory.

YY: B.Pharm., MPH, Pharmaceuticals Fund and Supply Agency, Addis Ababa, Ethiopia. DBH: B.Pharm., MSc. in Pharmacy Practice, Lecturer, Mizan-Tepi University, Mizan, Ethiopia. WAY: B.Pharm, MSc., PhD, Research and Postgraduate Program Coordinator and Assistant Professor at Jimma University, School of Pharmacy.