A STUDY of the hitherto available local knowledge of herbal medicines is important, both in socio-economic and scientific perspective. This is to draw upon the rich store of ethno-medicinal knowledge.

Herbal medicine is still being used by a majority of the population, mainly in less developed countries as it is cheaper, easily available, reliable and familiar alternatives to imported synthetic drugs. Furthermore, when produced locally, they can reinforce the income and status of local inhabitants.

The recognition and development of herbal medicine offer treatment methods that are more environmentally benign, as they tend to be less toxic, produce fewer unanticipated side-effects, are more biodegradable, accumulate no drug residues in meat or feces and apparently do not trigger chemo-resistance.

Plant anthelmintics have been in the forefront of this growing awareness as they fall in the category of readily applicable elements of ethno-veterinary medicine in livestock development. Safe, efficacious and high-quality anthelmintics products are a normal requirement in many countries.

The effect of a product with no active drug is the continued suffering of the animal. Use of anthelmintics with inadequate amounts of the active ingredient will, in turn, encourage the development of anthelmintics resistance, since sub-optimal dosing selects for chemo-resistant populations and overdosing can result in residual amounts in the feces, which may influence further resistance.

These constraints in the use of synthetic western medicines in less developed countries underline the advantages of herbal remedies as an alternative treatment. They are cheaper and more reliable, they are known by users and their supply is more sustainable. As they have undergone many years of clinical trials, most of them do not contain acutely toxic plants and do not produce serious unanticipated side-effects. Since they do not contain substances such as fixatives, preservatives or hormones, they are presumably more biodegradable and lead to less bioaccumulation in patient bodies and the environment. Furthermore, it has been suggested that the diversity of herbal anthelmintics has precluded the occurrence of resistance despite many years of use.

Study of herbal medicine can serve to validate and enhance existing local uses and can give clues to remedies with further potential. There are, however, other reasons for continuing interest and research such as they fall into the category of readily applicable elements of ethno-veterinary medicine in livestock development.

Re-emergence of herbal medicine: Greater and more organised use of herbal medicine as a whole also supports the Convention on Biological Diversity, held on June 1992, United Nations Conference on Environment and Development in Rio de Janeiro and duly signed by 154 countries (excluding the United States) and initiated in December 1993, after final ratification by 30 countries (Government of Denmark, 1996). The convention aims at a commitment to cooperation between the contracting countries with regard to the conservation and sustainable use of the diversity of animals, plants and other living organisms and their habitats.

Wider use of traditional herbal medicine can help fulfill these aims through the organised use of medicinal plants. Furthermore, the convention seeks a reasonable division of the profit from the use of genetic resources. A country thus has a sovereign right over its resources (Government of Denmark, 1996, article 3) and is thereby assured of a monetary share in the possible marketing of a product from these natural resources.

Organised cultivation of medicinal herbs and the creation of local trade and industry based on the herbal products can bring more jobs, income and status to rural inhabitants. However, there are problems connected with the use of herbal medicine, the largest being the lack of scientific evaluation. Such evaluation is the most important step once information about indigenous uses of medicinal plants has been collected.

Constraints in using herbal medicines: The use of ethno-medicine, human and veterinary, is not so simple. Ethno-medicine does not follow western paradigms of scientific proof of efficacy, which might be one of the main arguments against the use of traditional medicine today. As it is a relatively new area of academic study, many scientists and veterinarians still consider it pure superstition without a place in reality, the domain of “quacks”.

The inconvenience of preparing or using some remedies, the seasonal availability of certain plants, the scarcity of treatments against infectious epidemic diseases, the ineffectiveness of some treatments, the existence of harmful practices and the often inadequate ethno-diagnoses are the factors that may limit the use of herbal medicines.

The inconvenience of using some traditional remedies lies with the problems of collecting, preparing and administering the ingredients, which in some cases can be very time-consuming. Each constituent has to be found in special habitats and some ingredients might be seasonal.

Inadequate ethno diagnosis is probably the weakest aspect of traditional healthcare practice, owing to lack of patho-physiological understanding. The understanding of disease causality is rarely developed, and hence treatment and prevention can be inappropriate. Lack of sophisticated modern diagnostic technology for proper diagnosing is also a problem, even when the cause of disease is understood.

Poor diagnosis leads to ineffectiveness of some treatments. Furthermore, inadequate diagnosis or a lack of understanding of the disease can also lead to harmful prescriptions. In the case of a bacterial disease such as anthrax, which can be transmitted from animals to humans, the danger is not always known and the disease may spread accidentally by consumption of contaminated meat.

In human ethno-medicine, as well as in ethno-veterinary medicine, magic and religion are integral parts of the whole practice. Supernatural practices vary from simple incantations to complex ceremonies. Although such actions might have a psychosomatic effect in humans, their value in animals is uncertain.

What to do now?: Ethno-medicine stand at a crossroads. The decline and possible disappearance of all traditional practices lie in one direction, as traditional cultures come into contact with the western world. Rapid social and agricultural changes are taking place in many rural communities and therefore it is necessary to collect information on traditional patterns of use before these are disrupted.

Many healers possessing information are elderly and lack successors and, as they die, their knowledge dies with them. In the other far more desirable direction lie validation and improvement of ethno-medical knowledge. The collection and testing of natural products is one of two ways to discover pharmaceuticals; the other is laboratory synthesis.

Approaches to solve the problem: The ethno-botanical approaches assume that the indigenous use of plants can give hints about their biological activities. Particularly, in animal, self-medicating behaviour offers opportunities for the discovery of medicinal plants.

Biodiversity-based approach: This is based upon random collection and screening of diverse set of plant material samples for one or more biological activities. The reservoir for discovery is almost inexhaustible, as it contains all plant species. However, this undoubtedly makes it the more expensive approach, considering the relatively low chances of discovery.

Selection of plants based on chemotaxonomy: Another approach arises by the selection of plants based on chemotaxonomy, since plant secondary metabolites are often species or family-specific in their taxonomic distribution. The follow-up investigation of the ethno-medical uses of plants is widely accepted as the most productive plant surveying method. 74 per cent of all plant-derived drugs in clinical use worldwide have been discovered in this way. Information on plants used medically can be obtained through literature search and analysis, and through field inquiries, although this makes it a very slow process. This is one of the limitations to this approach, and at the same time what constitutes its urgency.

The most promising plants should be scientifically validated through systematic experiments, using indicators in laboratory animals and toxicity studies and, if these are positive, screening in domestic animals. This is a slow but very urgent process, as young people desert the traditional knowledge and lifestyles of their elders, leading to the possible disappearance of this knowledge.

Comparison of human ethno-medicine with ethno-veterinary medicine is important because in many cultures healers of human diseases treat corresponding animal disorders with the same herbs, drugs, methods, etc. However, reliance on healers’ information regarding human ailments might not be so important because healers of human ailments keep their knowledge secret, while ethno-veterinary information circulates freely. Herders often possess knowledge of anatomy and gross pathology through slaughtering, while human healers base their diagnoses solely on symptoms.

These are the ways to obtain ethno-medical and ethno-veterinary practices for appreciating and building upon local knowledge of husbandry and practices to seek sustainable development. In this way, herbal medicine may very well become a pioneer in turning local knowledge into global knowledge, through the recognition of local knowledge as an indispensable source of sustainable development for both people and the environment all over the world. This of course does not mean that traditional medicine should take over western medicine, but rather that we may benefit from a harmonious balance of both.