It is narrated from Sayyiduna Abu Mas'ud Ansari (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) forbade taking the price of a dog, the earnings of a prostitute, and the earnings of a soothsayer.
Imam Malik (may Allah have mercy on him) said: In my view, the price of every dog is disliked, whether it is a hunting dog or not, because the Messenger of Allah (peace and blessings be upon him) has absolutely forbidden the price of a dog.