Protests will be held outside Cardiff University today, against the institution's record when it comes to experimenting on animals.
The most recent figures obtained under a Freedom of Information request show that, in 2011, 51,826 animals were used for testing - 43,912 were mice.
Campaign group Animal Aid, one of the organisers of the demonstration, has described recent cancer research involving genetically altering mice as "agonisingly cruel and medically useless."
A petition against animal experimentation written by the other organisers, Cardiff Animal Network and Cardiff Animal Rights, gathered 2,000 signatures around in Cardiff in a day.
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