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.
More top news
It'll be an unsettled afternoon across Wales, with blustery winds and heavy rain. Gales expected in many areas.
A bronze war memorial which was moved from a fire damaged chapel in Aberystwyth seven years ago is now being returned to its original place.
The compulsory 'scores on the doors' system is helping to drive up standards across Wales, according to the Deputy Health Minister.