The Dogs Trust in Bridgend says over 600 dogs arrived at the centre last year - a record high.
Staff believe the struggling economy has played a part, but added many people simply don't realise the time and money needed to care properly for a pet.
They have urged would-be owners to think long and hard before committing to a dog.
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Staying rather cloudy for much of the day in the south, perhaps with a little rain at first.
Mostly dry with clear spells developing tonight in the north, which will allow some mist and fog patches to form.
It's usually something reserved for the coast, but today the Pro Surf Challenge added a stop at Snowdonia to its tour.