By law, UK institutions doing animal research must have a vet to oversee such work. What does your job involve?

The primary role is to look after the health and welfare of the animals. We have to do routine visits, and quality control of the animals' environments. We do a lot of health monitoring and advise licence holders on their project licences or experiments, refining them to reduce the impact on the animals. As part of that we are constantly advising on, for example, different anaesthetics or methods of collecting blood samples.

We also run all the training courses for licence holders and do research projects, trying to find objective measures of animal welfare. We are not in the position of accepting or vetoing programmes of work — my team feeds into the ethical review process of how welfare can be improved, but our role is an advisory one.

Animal well-being: welfare for macaques considers environment enrichment using cages outdoors. Credit: BFC FARM, ISRAEL

You specialize in the welfare of primates — which in Oxford generally means macaques. How have you been improving their lot?

The most significant difference was when my group got agreement from Oxford's research groups to include foraging in the primates' environment. It's now official — the National Centre for the Replacement, Refinement and Reduction of Animals in Research has just published guidelines on primate accommodation and care, which state 'all primates should be given the opportunity to forage daily'.

A primate in the wild will spend 75% of its time foraging for food — it's not natural to put it in a cage and give it a lump of food at meal times. Putting in wood shavings in which the food is hidden means they can forage around and look for it. It takes time, so they spend their time much more naturally, and they can use exploratory and social behaviours. It makes a huge difference to primate lifestyle.

This followed on from a general shift in practice towards housing primates together in groups. Twenty years ago, you might have had eight single cages in a room, each housing one monkey. Now you have all eight monkeys having the whole room. They can indulge in social behaviours and interact, and they can use the room three-dimensionally.

How do you train scientists?

In a number of ways. For example, we've made a DVD about how you can improve primate welfare by taking them out of cages and putting them into open rooms. It has made a significant difference, especially in the United Kingdom, where the majority of animals are held in groups.

You must come up against some fairly negative opinions.

It's always a challenge. As a vet surgeon you take an oath when you qualify that says that your constant endeavour will be for the welfare of animals committed to your care, but when you're dealing with experimental animals, their welfare has the potential to be compromised. That inevitably puts you in a difficult position. We have to balance the welfare against the quality of the science, and there are occasions when that is challenging. The scientific benefit may be absolutely clear and outstanding or it may be rather more vague.

Are there other sources of conflict?

I went to a conference last year where somebody — not a lab animal vet — came to speak from the Royal College of Veterinary Surgeons, and he said: 'When I came here I was wondering why anybody would work in this field, and now I've spent a day talking to you all, I still don't understand why anyone would work in this field.' It's because you are caught in the middle all the time. The anti-vivisectionists don't like you, because you're on the other side, as they perceive it. Some scientists perceive you as trying to change the way they do their work.

The whole ethical review process and the legislation is seen as a hurdle by many scientists. What you do have to protect against is the minority of over-zealous scientists who are single-mindedly pursuing their scientific goal. Those are the problem people — those few affect everybody else.

What impact does being squeezed from both sides have on your work?

One of the problems with the anti-vivisection movement is that because it targets everybody involved, it's really difficult to recruit people to this area. The net effect is that the anti-vivisection movement is bad for animal welfare.

You constantly have to think, 'because I'm making a difference and I'm improving animal welfare, I have to ignore the anti-vivisection pressure, and think about the medical benefits that come out of this'. In order to have medical benefits, there will have to be some animal use, and therefore you have to do your best for the welfare of the animals that are being used, and that's why I do it. I know that over the past 20 years I have made a difference to the welfare of animals that have been used, despite the pressures from the anti-vivisectionists on one side and the scientists on the other.