You can leave your Miniature Pinscher for a full month without washing him. However, if you notice any signs of dirt that cannot be brushed out, you should take him for a bath. They do not like the cold though, so always remember to use lukewarm water when washing your Miniature Pinscher, otherwise you might upset him. Once you have finished bathing him, wrap him up in a dry and warm towel so he does not feel the cold, or become cold because he is wet.