The number of licensed animal experiments started in the UK fell by 1% to just over 3.6 million in 2009.

That contrasted sharply with the previous annual report on animal testing from the UK’s Home Office, which showed a 14% rise in procedures year on year. The range of responses to this year’s figures, though, illustrates just how divisive the issue remains, even given the more open platform of scientific support for animal research in recent years and the impact on public opinion of animal rights extremism.

Despite the slight dip in 2009, the longer-term trend is still upwards and animal rights organisations were generally unhappy with the new data. As the Home Office pointed out, the total number of licensed procedures was 33% higher in 2009 than in 2000, mostly reflecting increased breeding of genetically modified (GM) or harmful mutant (HM) animals.

There were 834,000 more of these procedures in 2009 than in 2000, with 734,000 of the additional procedures involving mice. The “valuable insights provided by GM animals in biomedical research are such that their numbers are likely to continue rising”, noted Understanding Animal Research, the pro-research organisation formed from the Research Defence Society and the Coalition for Medical Progress.

It also highlighted that UK investment in biomedical research more than doubled in real terms over the decade to 2008, compared with an increase of over one third in the number of animal procedures. This “shows the commitment of the scientific community to the development and use of replacement and reduction techniques such as computer modelling and imaging techniques and the use of alternative resources such as human cell lines”, Understanding Animal Research said.

For Humane Society International, on the other hand, the latest Home Office data were another “depressingly familiar” record of “unacceptably high” numbers of animals used in research, exposing “the shameful legacy of science’s complacency about animal suffering where sentient creatures from mice to monkeys are still treated like dispensable research tools”.

GM impact

To illustrate the impact of genetic engineering on animal research in the UK, for the first time in 2009 procedures using genetically ‘normal’ animals accounted for less than half (48%) of the total number of experiments started that year. Procedures using GM and HM animals made up 42% and 111% respectively of the total (figures are rounded up).

Breeding to produce genetically modified animals and harmful mutants rose by 10% to 1.5 million procedures last year. Without these breeding techniques, the number of procedures would have fallen by 8% year on year to 2.1 million.

The vast bulk of animal experiments started in the UK during 2009 involved mice (73% of the total), fish (11%), rats (9%) and birds (4%). Dogs, cats and non-human primates combined were used in less than 0.5% of all procedures.

There were higher numbers of procedures involving mice (+9%), birds (+3%), sheep (+6%) and cattle (+89%). The volume of procedures involving non-human primates fell by 7% overall, with a reduction of 14% in the use of old-world primates but a 68% rise in experiments with new-world primates.

The Dr Hadwen Trust for Humane Research described the 90% increase in the number of new-world primates used for scientific procedures last year as “particularly concerning as most of these animal experiments study human diseases that do not exist in non-human primates, such as Parkinson’s disease”.

Understanding Animal Research pointed out, however, that the very low percentage of experiments involving non-human primates (NHPs) meant relatively small changes in numbers came out as substantial percentage variations year to year.

“In the medium term, we anticipate that the use of NHPs may increase,” it added. “This is partly because of their use to study neurodegenerative disorders (which are increasing due to our ageing population) and also because they are needed to test the new generation of biological medicines.”

The Dr Hadwen Trust welcomed the 10% fall in the number of toxicology tests on animals from 2008 to 2009, saying it “hopes this downturn will mark the beginning of a new trend towards the increasing use of animal replacement techniques”. In all, 12% of scientific procedures started last year were for toxicological purposes, the Home Office reported.

The new coalition government in the UK has committed to reducing the use of animals in scientific research. The British Union for the Abolition of Vivisection (BUAV) welcomed this pledge and said it looked forward to working with the government “to make meaningful and lasting change”.

In the meantime, it was “extremely disappointed” with the lack of any substantial reduction in the overall volume of animal procedures during 2009. “The UK should be leading the way in reducing animal testing,” commented BUAV chief executive Michelle Thew. “Unfortunately, these latest statistics show there is a long way to go.”