Animal welfare. No Leopoldo Stuardo

Transcription

1 Leopoldo Stuardo No Animal welfare Organisation Mondiale de la Santé Animale World Organisation for Animal Health Organización Mundial de Sanidad Animal

2 content Leopoldo Stuardo editorial Animal identification and product traceability from the farm to the fork must be progressively implemented worldwide forum Animal welfare update Scientific assessment and management of animal pain Welfare of fish in aquaculture Diclofenac in Asia and Africa repeating the same mistake? OIE news RNA-based biotechnologies: potential future impact on animal health new OIE publications meetings & visits news from headquarters regional activities Leopoldo Stuardo official acts news from colleagues epidemiology & animal disease control programmes activities of reference laboratories & collaborating centres international news book review Asad Rahmani special events P. Blandín agenda questions and answers ISSN FOUR ISSUES PER YEAR Chief editor: Bernard Vallat Copy editor: Bulletin Editorial Committee Printer: Jouve Design: OIE/Rialto/P. Blandin Subscriptions:

3 editorial Animal identification and product traceability from the farm to the fork must be progressively implemented worldwide Daniel Morzinski Marking animals to know who their owners are is a very ancient practice. Traditional livestock marking systems have existed since immemorial time. They were not generally motivated by health reasons. However, with the progressive intensification of animal production, new tools have been developed to enable animal marking methods to meet a multitude of new needs. Today, animal identification and traceability are important management tools in animal health and food safety. In many countries traceability of live domestic animals and of products of animal origin is a legal requirement. The pillars of a traceability system are founded upon the identification of individual animals or homogenous groups of animals, the ability to track their movements, proper identification of premises, and recording of this information in appropriate registers. In its capacity as a leading international standardsetting organisation for animal identification and traceability, the World Organisation for Animal Health (OIE) helps its Member Countries and Territories to implement animal identification and traceability systems in order to improve the effectiveness of their policies and activities relating to disease prevention and control, animal production food safety, and certification of exports. The OIE first addressed the issue of traceability in 1998 at the international seminar Permanent animal identification systems and traceability from farm to fork, in Buenos Aires, Argentina. In 2001 the OIE devoted an entire issue of the Scientific and Technical Review to traceability. In 2005 an ad hoc Group of experts was established and, in March 2006, the OIE Terrestrial Animal Health Standards Commission established a first series of guidelines on identification and traceability on behalf of OIE Members, which democratically adopted them in May 2007 as official OIE standards. Animal identification and traceability are important management tools in animal health and food safety Why have national or regional animal traceability systems? First of all they help producers and the institutions that support them to manage their animals more effectively, to implement herd/flock health programmes or to apply breeding or genetic improvement programmes. Whether in response to disease outbreaks or in the context of disease prevention, traceability can help countries to put in place a wide range of measures, including surveillance, early detection and notification of outbreaks, rapid response, control of animal movements, and zoning or compartmentalisation. With regard to food safety, traceability can help to prevent food contamination and to respond promptly and effectively in the event of a crisis. Furthermore, it can help to eliminate unjustified trade barriers, since a sound traceability system provides trading partners with assurances on the safety of the products they import. Traceability techniques can provide additional guarantees as to the origin, type or organoleptic quality of food products. There must be a means of linking the identification and traceability of live animals and the traceability of products of animal origin so as to achieve traceability throughout the animal production and food chain from farm to fork, taking into account the standards established by the OIE and the Codex Alimentarius Commission. Also, in consultation with relevant governmental agencies and the private sector, the Veterinary Authority should establish a legal framework for the implementation and enforcement of animal identification and animal traceability in the country. This legal framework will include elements such as the objectives, the scope, the animal species involved, the organisational arrangements including the choice of technologies used for identification and registration, the obligations of the parties, confidentiality, information accessibility issues and methods of information exchange. Various factors can influence the design of a national or regional animal identification and traceability system. Factors

4 editorial such as the animal and public health situation in the country, animal population parameters (such as species and breeds, numbers and geographic distribution), types of production, animal movement patterns, available technologies and their cost, as well as the way trade in animals and animal products is organised, must be taken into account at this level. Cost/benefit analysis and other economic, geographical and environmental considerations, as well as cultural aspects, should not be neglected when designing the system. With the technical collaboration of experts involved in the work of the Codex Alimentarius Commission, the OIE is planning to organise an international conference on animal identification and traceability in Buenos Aires from 17 to 19 March The aims of the conference will be to emphasise the importance and benefits of identification and traceability, to raise awareness of existing OIE and Codex standards, to determine future requirements for standards, and to provide advice and assistance on implementing standards, especially on behalf of developing countries. The participants will be from the national administrations concerned, animal research and production groups, and countries that have implemented effective traceability systems. Presentations will cover all sectors of livestock production as well as traceability of food products. The In consultation with relevant governmental agencies and the private sector, the Veterinary Authority should establish a legal framework for the implementation and enforcement of animal identification and animal traceability in the country particular needs of both developed and developing countries will be addressed, as well as the new technologies in animal production, such as animal cloning and transgenic animals, will create a need for additional arrangements to trace animals. Under certain circumstances authorities would have to trace every individual animal and animal product derived from these novel production methods. New technologies may also offer solutions. For example, DNA identification makes it possible to identify and monitor animals and animal products through to the retail level. Nonetheless, whether using high-tech or simple paper-based filing systems, the principles of traceability as defined in the Terrestrial Animal Health Code are universal, and apply equally in all situations. As a tool for controlling disease in animals and food safety, a traceability system should enable an animal product to be traced back to the animal s farm of origin, and to be identified throughout the food production chain. Traceability constitutes the link between animal health, food safety and the organoleptic characteristics of food linked to its origin. The forthcoming conference in Buenos Aires will help all countries to progressively implement effective traceability systems compatible with their resources while respecting the standards of both the OIE and the Codex Alimentarius Commission. Bernard Vallat Director General, OIE

5 forum Animal welfare update This sixth animal welfare update is designed to maintain awareness of progress with OIE activities involving animal welfare and is part of the OIE s commitment to communication and consultation. Communication and consultation are vital elements of the OIE mission statement: To provide international leadership in animal welfare through the development of science-based standards and guidelines, the provision of expert advice and the promotion of relevant education and research. This update provides further information on two important issues discussed at the September 2007 meeting of the permanent OIE Working Group on Animal Welfare, plus an update on membership of two new animal welfare OIE ad hoc groups on animal welfare, important regional activities and the Second OIE Global Conference on Animal Welfare, to be held in Cairo, Egypt, from 19 to 22 October Leopoldo Stuardo OIE animal welfare and research resources database The OIE s International Trade Department and Administration and Management Services Department are collaborating with Purdue University s Center for Food Animal Well-Being (United States of America) to develop a database on animal welfare educational resources. The database will identify useful contacts (organisations, international experts, areas of specialisation) and available educational materials and opportunities (scientific periodicals, books, CDs, DVDs, courses and internship opportunities). It is planned to make the database available to OIE Delegates and others in late 2008 and the project will be presented at the October Conference in Cairo. For additional information on this project please contact Dr Ed Pajor, Director, Center for Food Animal Well-Being, Purdue University at pajor@purdue.edu. Animal welfare education The Concepts in Animal Welfare syllabus, initially developed in 2003 by the University of Bristol Department of Clinical Veterinary Science (United Kingdom) and the World Society for the Protection of Animals (WSPA), aims to facilitate the teaching of animal welfare to veterinary students. A revised, updated and expanded version of this useful resource is nearing completion and will be available early in

6 forum The syllabus is contained on a CD-Rom and now consists of 35 teaching modules covering a wide range of animal welfare topics grouped into four categories: 1. Animal welfare science (9 modules) 2. Ethics (3 modules) 3. Applications of animal welfare science (14 modules) 4. Animals and society (9 modules). It is recognised that veterinary courses around the world are constructed according to various factors, including local conditions, culture, availability of resources and interests of the academic staff. Examples illustrating animal welfare situations around the world have now been included, while keeping the syllabus as generic as possible. Consequently, some modules or slides may be less appropriate to some universities. The updated version aims to be more comprehensive and more clinically relevant, with updates in the field of animal welfare science. In addition, animal training and motivation are briefly discussed; the link between animal abuse and interpersonal violence is made more explicitly in several modules; communication between veterinarians and clients is briefly addressed, and new types of questions, projects and discussion ideas have been included in some modules. It is hoped that the new illustrations will add to the overall understanding and every effort has been made to ensure that the language is more inclusive. For further information, please contact WSPA at: education@wspa-international.org Regional activities The importance of OIE Regional Commissions playing an active role in the implementation of OIE animal welfare guidelines on transport and slaughter and the need for all Member Countries and Territories to identify animal welfare contact or focal points has been emphasised by the Director General and recorded in General Session Resolutions. In the Middle East Region a comprehensive regional strategy has been developed and in the Asia, Far East and Oceania Region the OIE in collaboration with Australia held a successful workshop in Bangkok, Thailand, in November This workshop was followed by a second meeting in February 2008, where steps were taken to develop a detailed strategic plan for the region. Participants at the DAFF 1 and OIE Animal Welfare Workshop in Bangkok, Thailand, 6 &7 November DAFF: Australian Government Department of Agriculture, Fisheries and Forestry

7 forum The OIE ad hoc Group on laboratory animal welfare includes the following members: Front row (left to right) Dr Tsutomu Miki Kurosawa, The Institute of Experimental Animal Sciences, Osaka University Medical School, Japan Dr David Bayvel (Chair), Director Animal Welfare, MAF Biosecurity New Zealand, New Zealand Prof. Souilem Ouajdi, National School of Veterinary Medicine, University of Sidi Thabet, Tunisia Back row (left to right) Dr Christophe Joubert, Directorate-General for Research and Innovation, France Dr Gilles Demers, President ICLAS 2, Canada Dr Leopoldo Stuardo, Deputy Head of the OIE International Trade Department Dr Ekaterina Rivera Director, Central Laboratory Animal Facility, Biological Science Institute, Federal University of Goiás, Brazil Dr Judy MacArthur Clark, Chief Inspector, Animals (Scientific Procedures) Inspectorate, Home Office, London, United Kingdom Dr Kathryn Bayne, Senior Director and Director of Pacific Rim Activities, AAALAC International 3, United States of America New ad hoc groups The OIE ad hoc Group on laboratory animal welfare met for the first time at the OIE Headquarters in Paris, France, from 5 to 7 December The OIE ad hoc Group on animal welfare and livestock production systems will meet from 8 to 10 April This Group includes the following members: Dr Carlos A. Correa Messuti (Chair), Ministerio de Ganadería, Agricultura y Pesca, Uruguay Dr Xavier Manteca Vilanova, Profesor Titular de Universidad, Universitat Autònoma de Barcelona (UAB), Barcelona, Spain Dr Lars Schrader, Federal Agricultural Research Centre, Institute for Animal Welfare and Animal Husbandry, Germany Dr Abelardo B. Agulto, Board of Veterinary Medicine Professional Regulation Commission, Philippines Dr Musa Fanikiso, Director Department of Animal Health and Production, Ministry of Agriculture, Botswana Dr Joy Mench, Department of Animal Science, University of California, United States of America. Second OIE Global Conference on Animal Welfare Details of the scientific programme, requirements for the submission of posters and registration procedures for the Second OIE Global Conference on Animal Welfare are available on the OIE Web site. It is anticipated that there will be considerable interest in this Conference and the OIE has been advised that hotel accommodation may be difficult to secure due to the high level of tourism in this region. Early registration for the Conference is strongly recommended!! It is hoped that this update is proving useful to Bulletin readers. Your suggestions for material to be included in future issues will be welcomed. A.C. David Bayvel Chair, OIE Working Group on Animal Welfare 2- ICLAS: International Council for Laboratory Animal Science 3-AAALAC International: Association for Assessment and Accreditation of Laboratory Animal Care International

8 forum Scientific assessment and management of animal pain Denormadie-PACE Since 1924, when the World Organisation for Animal Health (OIE) was established, great advances have been made in the scientific understanding of the causes, prevention and treatment of animal diseases. Infectious diseases, together with nutritional, environmental and genetic disorders, and the relevance of the condition of the animal for its susceptibility to infectious diseases, have all received worldwide scientific attention. This work has been very successful in improving the health status and productivity of animals on a global scale. However, it is only during the last 20 to 25 years that animal welfare itself has been given explicit attention. The improvements in welfare that occurred previously were a natural outcome of this work, because animal health is a key factor in animal welfare. Now that increasing attention is being paid by scientists to the causes, consequences, minimisation and management of animal suffering, the OIE anticipates that important improvements in animal welfare will occur globally. With the intimate linkage of animal health and animal welfare in mind, the Members of the OIE in 2002 (now 172 Member Countries and Territories), unanimously supported extending the Organisation s mandate to include animal welfare. Subsequently, the OIE permanent Working Group on Animal Welfare was established to guide the implementation of this extended mandate. Four ad hoc Groups of experts were formed to develop international guidelines in the following specific areas: slaughter for human consumption, land and sea transport of animals, and humane killing of animals for disease control purposes. Following the adoption of these guidelines in 2005, the OIE continued to pursue its global animal welfare initiative with the formation of ad hoc Groups on relevant current topics, including: the control of stray dog populations, laboratory animal welfare and livestock production systems. Evidence of the OIE s leadership in setting sciencebased international standards for animal welfare has been highlighted through two further activities. The first of these was the publication of the Proceedings of the Global Conference on Animal Welfare, hosted by the OIE in Paris, France, on February This reflects the OIE s commitment to communicate and raise awareness of animal welfare issues globally. The Conference was attended by OIE Members and representatives of the private sector, international animal welfare NGOs 1 and scientific and professional organisations. Secondly, in 2005, the OIE published a special issue of the OIE Scientific and Technical Review on Animal welfare: global issue, trends and challenges. This provided a wider perspective on animal welfare as it pertains to the objectives, development and implementation of the OIE s international guidelines on animal welfare. Animal welfare may be characterised in various ways. Although there is ongoing discussion about the most appropriate way to define and describe animal welfare, there is general agreement that an animal s welfare status relates to what the animal itself experiences on a continuum between positive experiences, representing Paloma Blandín 1- NGOs: non-governmental organisations

9 forum good welfare, and negative experiences, especially markedly negative ones, representing suffering. The mental state of the animal is therefore very important. In a negative sense, this mental state can include anxiety, fear, distress of various kinds and pain. Negative mental states can arise because of external challenges, such as frightening situations. They can also arise because of functional changes within the animal due to nutritional, environmental, health and behavioural aberrations, disruptions or restrictions. Examples are hunger due to starvation or pain due to injury or a disease-induced pathology, Pain is among the most unpleasant, or noxious, experiences a person can have. Moreover, depending on its intensity, character and duration, pain can undoubtedly cause severe suffering in humans. It is increasingly accepted that this is also true for animals. Thus, the welfare of an animal experiencing significant pain will be compromised. This has motivated national advisory bodies in various countries and regions, including Australia, New Zealand and the European Union, to recommend that steps be taken to avoid or manage animal pain in order to minimise the suffering it would otherwise cause. The science of understanding animal pain, and its management, is still developing, and this is reflected in an ever-increasing body of peer-reviewed literature. Nevertheless, validated strategies for pain management are available and there are opportunities for scientific advances to be more closely reflected, as appropriate, in government policies and industry practices. At the same time, it is important to take account of the constraints facing developing countries and the increasing worldwide demand for food. In recognition of this, and the relevance of animal pain and pain management to its Global Animal Welfare Initiative, the OIE has commissioned an issue of the Technical Series. Its purpose is to assist the reader to gain a clearer understanding of current scientific thinking and likely directions of scientific research in future. Preparation of this issue has been facilitated by including updated versions of papers presented to the Australian Animal Welfare Strategy (AAWS) Science Summit on Pain and Pain Management, which was held in Melbourne on 17 May Other international experts have also contributed to this issue

10 Welfare of fish in aquaculture Aquaculture is of increasing importance as a source of protein for human consumption. According to the United Nations Food and Agriculture Organization (FAO) (9), 43% of fish for human consumption in 2005 came from aquaculture. The increase in fish farming has raised the question as to whether modern fish farming fulfils the welfare principles laid down in the so-called five freedoms. A number of studies have indicated that there is cause for concern about fish welfare (2, 4-6). In light of these studies, the European Food Safety Authority (EFSA) has appointed expert committees to undertake work on the welfare of various fish species, with a view to publication in Why worry about fish welfare? There are indications that the public, particularly in the industrialised world, consider that fish are entitled to good welfare (12). As consumers begin to enquire about welfare in industrial fish farming, the production sector cannot ignore fish welfare; bad publicity may affect the sales of farmed fish (4). Public concern may relate to the fact that many people believe we have a moral obligation to the animals we keep and control. Furthermore, science has brought insight into the complex lives of fish, their capacities for learning and social interactions. However, the most important factor is the growing evidence that fish are sentient and can feel pain. Sentience and pain in fish For several years, discussions have been taking place regarding fish consciousness and the possibility of fish feeling pain. Rose (14) argued that fish cannot feel pain since they lack a neocortex and when they display responses to noxious stimuli it is merely an unconscious reflex. However, other scientists have shown significant evidence of nociception in fish and demonstrated discomfort when noxious substances have been administered (16, 18) and have formed the opinion that fish are sentient and are able to feel pain (6, 7). Sentience is usually seen as a prerequisite when considering welfare. It refers to the ability of an animal to experience comfort and discomfort. It is thus a key issue when considering animal welfare (4). Pain is defined as an aversive sensation and feelings associated with actual or potential tissue damage (3, 4). Pain is normally associated with poor welfare. According to Broom (4), there is evidence that some species of fish, as well as cephalopods and decapods, have perceptual ability, pain and adrenal systems, emotional responses, long- and short-term memory, complex memory and the capacity for social learning. Fish have the necessary areas within the brain (e.g. pons, medulla, thalamus) for nociceptive processing to occur (17). It has been argued that fish possess the same type of specialised receptors to detect noxious stimuli as do birds and mammals (1). Neuroanatomical and neurophysiological studies have shown that nociceptors able to detect noxious stimuli exist in fish (i.e. nociceptive neurons in the skin) (15, 16). It has been shown that some fish species have two types of nociceptors, A-delta and C fibres present in peripheral nerves, indicating that pain may be modulated in fish (2, 4, 15, 16). It has also been shown that the transmitters substance P and enkephalin (opioid, -endorphin), which act as endogenous analgesics in mammals, are also present in fish (4, 13). Ehrensing et al. (8) showed that the response to analgesics is the same in goldfish as in rats. Welfare indicators Welfare indicators in fish may be abiotic or biotic. Abiotic factors include a range of water quality parameters, such as oxygen content, ph, salinity, temperature, management procedures, the design of tanks and net cages, as well as handling and sorting practices. Biotic factors include fish density, feeding, genetics and health issues (diseases)

11 forum How to achieve good welfare conditions In order to achieve good welfare conditions in fish farming, fish should be offered feed that is optimal in nutrient content, quantity and physical appearance for the species in question. The environmental conditions regarding farm design (tanks, cages), water quality (oxygen content, temperature, etc.) and stocking density should be appropriate to the species and life stage in question. It is also important to implement good management procedures in order to prevent injuries, prevent diseases (vaccination) and detect and report disease outbreaks quickly. Legislation and guidelines While animal welfare legislation was introduced in England as early as in 1822, it was not until the end of the 20th Century that the protection of fish was included (12). In the Holmenkollen guidelines, it was suggested that principles ensuring health and welfare should govern the aquaculture industry (19). An important step forward was the OIE Strategic Plan (21), that had as a key objective the development of international animal welfare standards including for aquatic animals (10, 11). Fish welfare is increasingly being considered in national animal welfare legislation globally, as reported by Mejdell et. al. (12). The European Council has also called for welfare provisions in regard to fish farming. OIE work in aquatic animal welfare In aquaculture, human intervention may significantly affect farmed fish welfare and it is thus important for the OIE, as the leading international standard-setting organisation in the field of animal welfare, to develop guidelines for aquatic animals, as has already been done for terrestrial animals (10). Welfare issues for aquatic animals have been discussed in the OIE Working Group on Animal Welfare (WGAW) since During this period, texts have been prepared, based upon the scientific work of ad hoc Groups convened for the purpose. At the most recent meeting of the WGAW, in 2007, members were briefed on new versions of the documents Introduction to OIE guidelines for the welfare of aquatic animals, Guidelines for the transport of fish by boat, Guidelines for the land transport of fish, Guidelines on slaughter of farmed fish for human consumption and Guidelines for the humane killing of fish for disease control purposes, that had been updated to take into account the comments of OIE Members on previous draft texts. It was agreed that, for the moment, the guidelines should relate to farmed fish and not to invertebrates as there is well established scientific evidence that finfish can feel pain. The WGAW recommended some modifications to the draft texts and these were sent to the Aquatic Animal Health Standards Commission for further consideration. Conclusion Despite the considerable progress made to date, there is still relatively limited knowledge and research regarding sentience and pain in aquatic animals and the welfare needs of aquatic animals (20, 12). It is thus important for the OIE to continue its work in the field of aquatic animal welfare in order to establish an appropriate framework for protection of these animals, as has already been done for terrestrial animals. Acknowledgement The author thanks Dr Cecilie Mejdell, National Veterinary Institute, Oslo, Norway for valuable comments and suggestions. Tore Håstein Retired, senior advisor National Veterinary Institute P.O. Box, 8156 DEP 0033 Oslo, Norway

12 forum References 1. Braithwaite V.A. & Boulcott P. (2007). Pain perception, aversion and fear in fish. Diseases of Aquatic Organisms, 75, Mejdell C., Lund V. & Håstein T. (2007). Fish welfare in aquaculture. Journal of Commonwealth Veterinary Association, Anniversary 2. Braithwaite V.A. & Huntingford F.A. (2004). Fish and welfare: do fish have the capacity for pain perception and suffering? Animal Welfare, 13, Celebrations, 23 (2), Rodrigues Moldes I., Manso M. J., Becerra M., Molist P. & Anadon R. (1993). Distribution of substance P-like immuno-reactivity in the brain 3. Broom D.M. (2001). Evolution of pain. R. Soc. Med. Int. Congr. Symp. Ser., 46, of the elasmobranch Scyliorhinus canicucula. J. Comp. Neurol, 333, Broom D.M. (2007). Cognitive ability and sentience: which aquatic animals should be protected. Diseases of Aquatic Organisms, 75 (2), Rose J.D. (2002). The neurobehavioural nature of fishes and the question of awareness and pain. Reviews in Fisheries Science. 10 (1), Cawley G. (1993). Welfare aspects of aquatic veterinary medicine. In aquaculture for veterinarians: fish husbandry and medicine (L. Browne, ed.). Pergamon Press, Oxford, Sneddon L.U. (2002). Anatomical and electrophysiological analysis of the trigeminal nerve in a teleost fish, Oncorhynchus mykiss. Neuroscience Letters, 319, Chandroo K.P., Duncan I.J.H. & Moccia R.D. (2004a). Can fish suffer? Perspective on sentience, pain, fear and stress. Applied Animal Behaviour Science, 86, Sneddon L.U., Braithwaite V.A., & Gentle M.J. (2003). Do fish have nociceptors? Evidence for the evolution of a vertebrate sensory system. Proc. Royal Society of London, 270, Chandroo K.P., Yue S. & Moccia R.D. (2004b). An evaluation of current perspectives on consciousness and pain in fishes. Fish and Fisheries, 5, Sneddon L.U. (2004). Evolution of nociception in vertebrates: comparative analysis of lower vertebrates. Brain Research Reviews, 46, Ehrensing R.H., Michell G.F. & Kastin A.J. (1982). Similar antagonism of morphine analgesia by MIF-1 and naloxone in Carassius auratus. Pharm. Biochem. Behav., 17, Southgate P. & Wall T. (2001). Welfare of fish at slaughter. In Practice, 23 (5), Sundli A. (1999). Holmenkollen guidelines for sustainable 9. Food and Agriculture Organization of the United Nations (FAO) (2006). Trends in consumption. Action.do?dom=topic&fid=3463 (accessed on 28 April 2008). aquaculture (adopted 1998). In Sustainable aquaculture, Food for the future? (Svennevig N., Reinertsen H. & New M., eds) Proc 2nd Int Symp on Sustainable Aquaculture, Oslo, Norway, 2-5 November Håstein T. (2007). OIE involvement in Aquatic Animal Welfare: the need for development of guidelines based on welfare for farming, transport and slaughter purposes in aquatic animals. In The OIE Global Conference on Aquatic animal Health (B. Dodet & the OIE Scientific & Technical Departments, eds). Dev. Biol. (Basel), Karger, A.A. Balkema, Rotterdam, Turnbull J.F. (2006). Current issues in fish welfare. Journal of Fish Biology, 68, World Organisation for Animal Health (OIE) (2001). OIE Third Strategic Plan, , Håstein T., Scarfe A.D. & Lund V. (2005). Science-based assessment of welfare: aquatic animals. In Animal welfare: global issues, trends and challenges (A.C.D. Bayvel, S.A. Rahman & A. Gavinelli, eds). Rev. sci. tech. Off. int. Epiz., 24 (2),

13 forum Diclofenac in Asia and Africa repeating the same mistake? For the past fifteen years, diclofenac, a non-steroidal anti-inflammatory drug (NSAID), has been available for veterinary use over pharmacy counters throughout the Asian countries of Pakistan, India and Nepal. In these countries this drug has been widely used as a pain killer for the symptomatic treatment and management of inflammation, fever and painful conditions associated with disease or injury in domestic livestock. However, when applied empirically, without an accurate, professional diagnosis, it rarely results in a cure and many animals still die in spite of treatment. Diclofenac is manufactured by a South American pharmaceutical company which is reported by BirdLife International s African office to be already exporting the drug to 15 African countries. Diclofenac, now out of patent, is marketed under many brand names in many different countries. It was originally developed by a pharmaceutical company for human use, which is actually the primary market. On the Indian subcontinent it is customary to put out dead livestock for consumption by vultures and other scavengers, and the availability of such carcasses to vultures is high even in areas where meat-eating is practised. The veterinary drug diclofenac has been Throughout South Asia, vultures and other scavengers have played a hugely the cause of vulture decline in Asia. important hygienic role in clearing up dead livestock. Scavengers have to be saved to keep the Vultures are exposed to diclofenac when they consume the carcasses of environment clean and free from livestock that have been treated with this drug and have subsequently died within a diseases due to unattended carcasses few days of treatment. Courtesy Dr Nita Shah, BNHS (Bombay Natural History Society) vulture advocacy programme

14 Courtesy Dr Nita Shah, BNHS vulture advocacy programme forum This drawing depicts the past scenario while the vultures were present Gyps spp. vultures (the Griffon vultures) are extremely sensitive to diclofenac, which even in very low concentrations causes acute kidney failure and death. In South Asia, the populations of the endemic Oriental white-backed (Gyps bengalensis), slender-billed (Gyps tenuirostris) and long-billed (Gyps indicus) vultures have declined dramatically by more than 95% since the early 1990s, and the evidence suggests that the few that are left continue to decline at between 15% and 50% per year. These three species which, together, just 15 years ago, used to number tens of millions (possibly 40 million of one species in India alone), are now almost unbelievably at serious risk of global extinction and are listed as Critically Endangered by the International Union for Conservation of Nature (IUCN 2004). Scientific evidence following the observation of waste disposal practices of carcases confirms without doubt that the veterinary use of diclofenac is the main cause of these declines (Green et al. 2004) throughout the Indian subcontinent. However, there are effective, safe, alternative drugs available, (e.g. meloxicam), which it is hoped will soon replace diclofenac in the veterinary pharmacopeia. Fortunately meloxicam is also out of patent and could now be produced at comparable prices to diclofenac. It is hoped that some other substitute drugs may also prove to be vulture-safe, although each drug should be thoroughly tested, as was the case with meloxicam, to confirm this. As a consequence of the collapse of South Asian vulture populations, national and international conservation organisations have concluded that it is essential to ban the use of diclofenac in domestic livestock so as to remove it as a toxic contaminant of the food of wild, scavenging vultures. At a meeting of the National Wildlife Board in March 2005, the Government of India announced that it intended to phase out the veterinary use of diclofenac within six months. In 2006, the Governments of India, Pakistan and Nepal all banned the manufacture of diclofenac in these countries. This sends a very clear signal and is welcome. However, retail sale of diclofenac not manufactured for veterinary use remains legal in these countries, so full bans on retail sale for veterinary use may be necessary. A further and potentially serious ecological consequence of the disappearance of the scavenging vultures throughout the Indian subcontinent is that there may be an increase in the numbers of feral domestic dogs, which are major vectors of rabies, a disease that kills up to 20,000 Indians (the majority of them children) each year (Sudarshan et al. 2007). In the absence of vultures, the increased availability of carrion upon which feral dogs feed can be expected to boost their populations. It is reported (2003 data) that there has already been a 35% increase of feral dogs in India. These animals also pose many other health and safety threats

15 Courtesy Dr Nita Shah, BNHS vulture advocacy programme forum This drawing depicts present scenario in absence of vultures we have dogs at the carcass dumps causing the rise in incidence of rabies The veterinary use of diclofenac in African countries Should the use of diclofenac in African countries result in a similar chain of exposure to vultures, it could quickly threaten the Cape vulture (Gyps coprotheres) already in grave danger of extinction, and would further threaten Ruppell s griffon vulture (Gyps rueppellii), the white-backed vulture (Gyps africanus), and the Eurasian griffon vulture (Gyps fulvus). Gyps vultures are very wide ranging. For example, in just one year a Cape vulture, satellite-tagged in Namibia, covered at least 64,000 km through six countries: Namibia, Angola, Botswana, Zambia, Zimbabwe and South Africa. Exposure to diclofenac in a single carcass in any one of the range states of these species could prove fatal. Consequently, veterinary use of the drug could threaten the more common species as well as those that are already rare. Surveys by veterinarians and zoo staff have documented the outcome of experimental exposure of over 870 scavenging birds of 79 species to NSAIDs. Toxicity was reported for drugs, including the widely used carprofen and flunixin, in raptors, storks, cranes and owls, suggesting that the potential adverse impact of some NSAIDs may extend beyond the Gyps vultures and could be significant for all vultures as well as for other bird species. In Africa these might include the threatened Egyptian vulture (Neophron percnopterus) the white-headed vulture (Trigonoceps occipitalis) and the lappetfaced vulture (Torgos tracheliotus). In contrast, the above surveys reported no mortalities for the NSAID meloxicam, which was administered to over 700 birds of 60 different species. This study was followed up by rigorous experimental testing on both African and Asian Gyps vultures. No adverse effects were detected. The relative safety of meloxicam indicates that it is a suitable substitute NSAID for the toxic diclofenac. A survey of veterinarians and veterinary suppliers by the Wildlife Conservation Society of Tanzania is underway to establish whether diclofenac is already widely stocked and sold in Tanzania. Partners in other African countries will be undertaking similar surveys. As a consequence of the collapse of the South Asian vulture populations, national and international conservation organisations have concluded that it is essential to ban the veterinary use of diclofenac for livestock so as to remove it as a contaminant of the food of wild vultures and to replace it, where there is a demand for an NSAID, with the nontoxic, safety-tested drug, meloxicam. Diclofenac is not licensed for veterinary use in Europe or North America. However, it should be noted that diclofenac is widely licensed for medical use in

16 forum Reférences Green R., Newton I., Shultz S., Cunningham A., Gilbert M., Pain D.J. & Prakash V. (2004). Diclofenac poisoning as a cause of vulture population declines across the Indian subcontinent. Journal of Applied Ecology, 41, Sudarshan M.K., Madhusudana S.N., Mahendra B. J., Rao N.S.N., Ashwath Narayana D.H., Abdul Rahman S., Meslin F.-X., Lobo D., Ravikumar R. & Gangaboraiah. (2007). Assessing the burden of human rabies in India: results of a national multi-center epidemiological survey. International Journal of Infectious Diseases, 11, many countries for the treatment of human ailments, and in some places the human drug is reaching the veterinary market. In India, where vultures are central to the customs of the Parsee community, human corpses are put out for consumption by vultures. Here, there is an added danger that where humans have been treated with the drug they may contain sufficient diclofenac to poison a scavenging vulture. The key solution in South Asia is seen as converting all veterinary practitioners and livestock owners to using meloxicam (or any other demonstrably vulture-safe alternative) instead of diclofenac. The Bombay Natural History Society s Vulture Advocacy Programme is working with the Government of India to achieve this and is, with support from the United Kingdom s Royal Society for the Protection of Birds (RSPB) and other partners, establishing costly conservation breeding programmes to keep alive the option of reintroduction in the future. Surely we can avoid the very real risk of repeating this conservation and environmental catastrophe across Africa (or elsewhere) by preventing diclofenac from being taken up in veterinary practice and sold over pharmacy counters. If needed, vulture-safe alternatives, like meloxicam should be used. During the OIE Conference in Dakar Senegal in March 2008 on the Harmonisation and improvement of registration and quality control of Veterinary Medicinal Products in Africa, a Resolution was adopted unanimously by more than 160 Delegates present to request Members to consider their national situation with the aim to seek measures to find solutions to the problems caused by the administration of diclofenac in livestock. M.H. Woodford, OIE Working Group on Wildlife Diseases, C.G.R. Bowden, Royal Society for the Protection of Birds & Dr Nita Shah, BNHS vulture advocacy programme Please see illustrations on page

17 OIE news RNA-based biotechnologies: potential future impact on animal health Scope of paper New biotechnologies offer the potential to change how we use and care for animals. Most advances enable improvements with regard to specific diseases or how we manage animal resources. Now and again a biotechnology appears that could have significant impact on animal health, although few have the potential to impact across all aspects of animal breeding and disease. Perhaps the best recognised biotechnology that has this broad application is vaccination. There is now general optimism that ribonucleic acid (RNA)-based technologies may have a similar influence on how we mitigate animal disease. Moreover, for a variety of reasons the impact may be swift and organisations such as the OIE should be in a position to anticipate this impact. This position paper was prepared for discussion at the November 2007 meeting of the OIE ad hoc Group on biotechnology. The aim of this paper is to introduce the different RNA-based technologies, identify their potential applications in the context of animal health, describe examples of experimental projects already in development in this context and provide a conclusion indicating options to enable the OIE to foresee the impact of RNA-based technologies on animal health in the next two decades. The scope is further limited to strategies that may impact on infectious disease, although as RNA-based technologies develop other aspects of animal life could be modulated, resulting in enhanced animal health. RNA-based technologies RNA is generally associated with gene transcription. In this context, messenger RNA (mrna) codes for the proteins that make up a cell and are thus the basic building blocks of biological life. Other types of RNA exist. During the second half of the last century it was recognised that non-coding RNAs occur and it is now understood that many have essential functions for the growth and survival of biological organisms. RNA-based technologies exploit a range of these non-coding RNAs. There are a range of subtly different RNA-based technologies, each with its own attributes and varying in their potential to be commercially applicable. The first to be identified was antisense RNA. More intriguing was the discovery of RNAs that displayed enzymatic activities, such as the ribozymes. However, it was the discovery of RNA-interference (RNAi) that finally catapulted RNA-based technologies from laboratory tools to what is now optimistically seen as the disease intervention product for the 21st Century. Reflecting the excitement surrounding this discovery, it took a mere eight years for Andrew Fire and Craig Mellow, discovers of the gene silencing phenomenon of RNAi in animals, to be awarded the Nobel Prize in Medicine. Although there are a number of RNA-based technologies, which differ in their mode of action, they all act by reducing the amount of functional protein produced from a given gene

18 OIE news RNA-interference (RNAi) Although less than a decade has passed since RNAi was shown to work in mammals, this term has become commonplace in discussions about regulating gene expression. RNAi molecules come in different forms for example, sirna, shrna and mirna (see below). All share the property of homology-dependent targeting of mrna processing. The important functional component of RNAi is a short single-stranded RNA molecule of about 20 nucleotide bases in length which can bind directly to a target messenger RNA. If this interaction occurs in the nucleus it usually leads to the destruction of the target mrna, whereas if it occurs in the cytoplasm the result is reduced translation of the mrna into protein. Both lead to reduced gene product and this activity is often called gene knockdown. Different forms of RNAi molecules exist. In their most basic form, they comprise small doublestranded RNA molecules called short interfering RNAs (sirnas). One strand of the sirna molecule shows complete homology with the target RNA, i.e. if the target RNA has a uracil nucleotide then the sirna will have an adenine nucleotide. These RNA molecules are 20 to 25 nucleotides long and degrade rapidly, limiting their application to the laboratory. For prolonged activity the sirna must be incorporated into an expression vector that functions like a gene. The first such vectors were based on polymerase-iii gene promoters and, due to their physical structure, are termed short hairpin RNAs (shrnas). In 2001, Thomas Tuschl demonstrated that they could function in mammalian cells. Second-generation vectors utilise polymerase-ii promoters, offering both spatial and temporal regulation of knockdown activity, and are based structurally on naturally found RNA molecules called micrornas (mirnas). mirnas differ from sirnas in that they show only partial sequence homology with the target mrna. Antisense RNA and ribozymes Although currently most optimism for the successful application of RNA-based technologies revolves around the use of RNAi, other types of RNA-based technologies exist. Antisense RNAs are singlestranded RNAs that are complementary to the target mrnas that function to block translation. Unfortunately, application of this type of molecule has proved difficult. Retrospectively, it seems likely that many of the effects reported for antisense RNAs should instead be attributed to RNAi events. Antisense RNAs physically block cell processes while RNAi molecules evoke normal cellular enzymes to destroy the target RNAs. There are, however, some RNA molecules that contain their own enzymatic activity. Ribozymes, which specifically bind to and subsequently catalyse the cleavage of other target RNA molecules, represent an interesting alternative to RNAi. Again, the application of ribozyme design has proved difficult. Other RNA-based technologies and future technological developments Though perhaps more restricted in potential applications, other forms of RNA may have specific uses in animal health. Examples include RNA decoys, which mimic normal RNA molecules and compete in RNA molecule formation. RNA decoys usually harbour modified chemical components that present physical constraints on RNA structure and/or alter RNA binding kinetics. Looking to the future, nucleic acid analogs are under intense investigation. These modified molecules provide more stable RNA molecules, significantly enhancing their application potential. An early example is the morpholino, though its application in mammals is questionable. More recently, many forms of promising nucleic acid analogs have been developed, such as locked nucleic acids (LNAs) and peptide nucleic acids (PNAs), which have dramatically improved biostability. It is likely that more analog RNA molecules will be developed in the near future. Delivering RNA-based molecules In practice there are two alternative delivery strategies for RNA-based technologies. First they could be delivered in a gene therapy or a

19 vaccination type of approach. Alternatively they could be the basis of a transgene delivered to the germline and resulting in a transgenic or genetically modified animal. Depending on the type of RNA-based molecule delivered, the effect could be either a transient or stable change in gene activity. For example the use of sirna would result in a transient alteration in gene activity somewhat similar to vaccination, except that the timescale would most likely be considerably shorter that the intended protection period offered by vaccination. This timescale will impact on what one could use sirna for. With a gene therapy delivery strategy the aim would be to enable the change in gene activity to be present for as long as cells carrying the RNA-based molecule survive in the animal. Analog RNA molecules make this delivery strategy attractive. Alternatively, shrna or mirna could be delivered as a transgene to generate genetically modified animals. This approach would result in the stable inheritance of the RNAi transgene by offspring and subsequent generations of animals derived from the original founder animal. For both gene therapy delivery and transgenic strategies, more elaborate RNAi molecule designs that incorporate inducible gene knockdown activity are possible. In this case the RNAi molecule would only be produced in the presence of the appropriate inducing factor (perhaps responding to a pathogen or toxic insult). With regard to delivery routes, many of the animal welfare and delivery issues for transient delivery will reflect those already addressed for vaccination. Repeat delivery may be required. Alternatively, the production of genetically modified animals may raise new issues relating to production procedures but may provide life-long benefits for advantageous phenotypes and the establishment of the genotype, which is passed to successive generations. Possible uses of RNA-based biotechnologies in animal health RNA-based approaches to regulate gene activity have been practised in the laboratory for some time. Although significant technical advances and validation of strategies mean that we are soon likely to see applications in animals in the field, most applications are still in the experimental phase. There are, however, several preclinical studies for applications in humans and it is reasonable to expect that these will accelerate the use of RNA-based biotechnologies in animals. In animals, the primary use currently foreseen for RNA-based technologies is to combat infection. There are two conceptual approaches to address infectious disease using RNA molecules: attacking the pathogen or bolstering the animal s immune response. The former will most likely involve viral diseases while the latter may have broader applications against a range of pathogens. Perhaps the most likely application of RNAbased biotechnologies will be to interfere with virus infection. This allows for a direct targeting of the pathogen by the RNA molecule. In effect, the RNA molecule will complement the animal s innate immune system, providing an additional barrier to infection or virus replication. Examples are provided to illustrate these approaches. Combating foot and mouth disease virus (FMDV) in cattle FMDV is a single-stranded RNA virus of the Picornaviridae and causes fever, blisters of the mouth and feet, weight loss and reduced milk production. Most animals recover from the disease. FMDV infection is endemic in many parts of the developing world and may be the cause of epizootics in developped countries. FMDV enters a host cell via a specific receptor. Once inside the cell, the virus makes new viral RNA molecules through a viral encoded polymerase. This life-cycle presents targets for RNA-based technologies. Reducing OIE news

20 OIE news the receptor, probably transiently, should confer reduced susceptibility to a wave of infection. Alternatively, targeting destruction of the viral polymerase could both target virus gene expression and viral genome replication, thus limiting disease progression in an infected animal. The use of RNA-based technologies against FMDV is particularly attractive. At least seven serotypes of FMDV exist with continual evolution within a serotype. The huge genetic variation that results and the lack of cross protection between serotypes is challenging for a vaccine design approach. In contrast, the viral polymerase is well conserved. If this type of intervention strategy were to prove effective it could have a major impact on animal disease; two-thirds of the pathogens on the OIE s former List A are RNA-based viruses. Proof of concept has been provided for FMDV and a number of human pathogens, including hepatitis virus, poliomyelitis virus and human immunodeficiency virus (HIV). Given the successful application of RNA-based technologies against retrovirus infection in humans, it is likely that similar approaches would be effective against animal retroviruses, such as Jaagsiekte, maedi-visna and equine infectious anaemia viruses. Interfering with influenza infection in poultry Highly pathogenic avian influenza is a serious infection of poultry (and other animals, including pigs) and represents a significant zoonotic risk. It is caused by a negative-strand RNA virus of the Orthomyxoviridae family. Infected animals display fever and various other symptoms, sometimes resulting in death. Due to the virus genome structure and replication strategy, mixing of genomic sub-fragments results in a rapid change of virus strains. The consequence is that vaccination only protects for a limited period. As described above, RNA-based technologies that target the virus genome may be effective in destroying the virus genome. Alternatively, an unusual step in virus replication may represent a more effective target for RNA molecules to attack. Newly made RNA strands incorporate a common lead sequence and decoys against this sequence are potent inhibitors of influenza virus gene expression. This approach is being experimentally tested with the anticipation that these decoys may prove to be useful in antiinfluenza virus therapeutics. Vaccines against influenza virus are available and there are also several drugs that can be used to treat the disease. Therefore, any validated RNA-based technology against this virus will probably be utilised in a strategy involving these other disease mitigation tools. What may make the RNA-based technologies attractive is that, unlike current vaccines, they would most likely be effective against diverse strains of the virus. Novel experimental strategies to combat disease Experiments are underway in animals to evaluate the RNA-based technologies described above. It is anticipated that within two to three years we will know how effective these can be. In parallel, much more speculative studies are being planned which could have a positive impact on animal disease and health. Expression of an RNA molecule could be targeted to a cell ingested by a pathogen, for example the gut epithelium or blood cells. The RNA molecule would be designed such that, once inside the pathogen, perhaps a tick or other blood sucking insect, it would cause the death of that pathogen. Notably, the proof of principle for this ingenious strategy has recently been established in transgenic plants. Alternatively, it may be possible to treat the animal with RNA molecules that target endogenous animal genes, rather than targeting the pathogen. This approach could be used to modulate cytokine levels, aspects of innate immunity or some other property that enhances an animal s ability to combat disease. For example, the level of the cell surface receptor that