Although the Wellcome Trust is more generally known as a funder of research into human biology and medicine, support of veterinary research is also an integral part of its activities. To reinforce the message that the Trust is keen to support international veterinary research, an awareness-raising initiative is being launched, so potential applicants in the UK and overseas are aware of the scope of research opportunities open to them.

Most of the Trust’s grant schemes can support animal health research: project and programme grants are complemented by a range of fellowship schemes open to veterinarian scientists at various stages of their scientific careers, giving considerable career progression and training opportunities. Importantly, many of these awards can also facilitate interaction and exchange with the international research community. For example, there are opportunities for scientists from Europe to train in centres of excellence internationally or to pursue research in an overseas location. For scientists with an interest in animal health based outside the UK, there are further dedicated schemes for training and research project support. Specific schemes encourage studies in developing countries. Other awards provide support for travel, symposia or collaborations between institutions in different countries.

Several scientists based outside the UK have been funded to research issues of local relevance. For example, Anil Nichari was awarded a Research Development Award to study the epidemiology of bovine tropical theileriosis in northern India, while Gerardo Munoz-Mantilla has investigated the role of the domestic dog in the transmission of Leishmania panamensis in Colombia.

A look at some of the work being undertaken by current grantholders highlights the variety of support available and the wide range of subject matter and the broad geographical spread of Trust-funded international veterinary research.

Dogs in Ethiopia

Rabies and other canine viruses in Ethiopia form the subject of a Research Fellowship in Tropical Medicine awarded to Karen Laurenson at the Royal (Dick) School of Veterinary Studies at the University of Edinburgh.

The rabies virus has a significant impact on public health in Ethiopia, where more than 90 per cent of human cases are contracted from dogs. Rabies can also cause significant economic losses when livestock are infected, while recent epidemics in the endangered Ethiopian wolf and African wild dogs have raised concerns about the conservation of rare species.

Although safe and effective vaccines against rabies and other important infectious diseases of dogs – such as canine distemper, infectious canine hepatitis and canine parvovirus – have been developed for domestic dogs, a poor understanding of how the viruses spread between and within different species leaves a question mark over how the vaccines should be used. Dr Laurenson is investigating the dynamics of viral transmission in domestic and wild populations and the possible consequences of different control strategies in domestic dogs in order to help determine the most effective approach to vaccination.

The study is being carried out in and around the Bale Mountains National Park in Ethiopia, an area that encompasses several towns and is home to numerous domestic and wild carnivores, including the critically endangered Ethiopian wolf.

A particular problem is the need to identify which canine species – domestic dogs, or wild carnivores such as jackals, civets, mongooses, wolves, foxes and hyenas – are the natural reservoir for these viruses. If the wild species are the main reservoir, vaccinating even a large proportion of domestic dogs will not eliminate the viruses from either domestic or wild populations, since the pathogens will keep re-entering the domestic population from the wild species.

As well as identifying the reservoir hosts, Dr Laurenson is studying factors affecting transmission and persistence, such as host species, population density and demographic structure, as well as ecological factors, in order to develop models of the spread of the disease in populations and improve control.

The research programme is expected to lead to a deeper understanding of the spread of pathogens in multispecies populations, and of effective control methods. More immediate benefits for the Ethiopian community will be improved public health in the study area, fewer economic losses through infection of livestock, and potentially protection of the endangered Ethiopian wolf.

Sheep in California

On completing his PhD at the University of Edinburgh, Dr Massimo Palmarini was awarded an International Prize Travelling Research Fellowship enabling him to study sheep pulmonary adenomatosis, otherwise known as jaagskiete, in California.

Jaagskiete is a naturally occurring lung tumour of sheep that leads to the accumulation of fluid within the respiratory tract (pulmonary adenomatosis). Jaagskiete is one of the most significant infectious diseases affecting adult sheep. It accounts for 70 per cent of sheep tumours in the UK and has a major economic and welfare impact globally wherever sheep are farmed (with the notable exception of Australia and New Zealand).

Circumstantial evidence has for many years pointed to a retrovirus – known as the jaagskiete sheep retrovirus (JSRV) – as the causative agent. However, the lack of an in vitro system for studying JSRV means that its exact role in the disease is still unknown.

During his fellowship, Dr Palmarini has successfully established a tissue culture system for JSRV, and has shown that this form of the virus induces the classical signs of pulmonary adenomatosis in experimentally infected animals – strong evidence that JSRV is the genuine cause of jaagskiete.

The identification of the aetiological agent of pulmonary adenomatosis in sheep will help studies of diagnosis and disease prevention. Moreover, with the new tissue culture system, it is now possible for the first time to produce JSRV infectious virus particles in vitro without relying on pathological material collected directly from infected sheep, which will greatly aid studies of the virus and how it actually causes disease.

Cattle in Tunisia

Theileria annulata, a single-celled parasite affecting domestic livestock in north Africa, Asia and southern Europe, is the focus of Chris Oura’s Advanced Training Fellowship in Tropical Medicine at the University of Glasgow.

Theileria annulata is one of a family of parasites that cause some of the most important diseases of domestic livestock worldwide. They are carried by ticks and enter the host animal’s bloodstream when the tick feeds. The parasites then invade leukocytes, causing them to proliferate. The infection leads to weight loss, enlarged lymph nodes, anaemia and often death.

In Tunisia, a less virulent strain of the parasite, developed by long-term in vitro culture of an infected cell line, is already being used to vaccinate livestock. Dr Oura is now attempting to work out why the cell line is so much less pathogenic while still being able to stimulate a powerful immune response, enabling it to be used as a vaccine.

An important aspect appears to be the ability of the parasite to complete its life cycle. In Glasgow, Dr Oura aims to establish the genetic differences between a disease-causing strain of the parasite that differentiates between two critical stages in its life cycle (from macroschizont to merozoite) in culture and a mutant cell line derived directly from it that does not differentiate. Once these genetic differences have been identified, he will compare them to the strain used to vaccinate livestock in Tunisia to see whether the same genes are responsible for the reduced pathogenicity of this vaccine cell line.

This work will lead to a fuller understanding of the genetic control of both the life cycle and pathogenicity of this important veterinary parasite, and has implications for future vaccine production.

External links

• Dr Karen Laurenson at the Royal (Dick) School of Veterinary Studies: Details of her research interests
• Research papers published by Massimo Palmarini with Professor Hung Fan at the University of California, Irvine
• Faculty of Veterinary Medicine at the University of Glasgow: Overview of veterinary parasitology research including that of Dr Chris Oura