Since they are dogs I would say not much if they are not specified to go to you since you did not raise them and they are use to the ex girlfriend. If she was not helping raise them and care for them then I would think you would have a chance.
Any money or property that she can not claim as hers you would get.
Who has possession of the animals? If the girlfriend has possession of the animals, then she can probably keep them unless they are valuable show animals worth a considerable amount. Are they pedigree animals and how many animals are involved?