YES absolutely. Ear mites in cats are dogs are common I don't know if there is a rat mite but certainly a number of mammalian mites I do not believe that cross species carrier is really likely. That being said I am not sure I would want to buy from a rattery that had mites either. Not for fear of the snakes picking it up but if there are mites but for me the conditions rodents are raised under matter ethically. I would be concerned for the health and well being of rats with mites. Have to spoken to the breeder? Perhaps you should, he/she may either let you know it is or has been dealt with or what is up. They maybe proactive and dealing with the issue. Or may not know about it. A supplier that is local reliable and easy to deal with is worth a little effort to maintain a good relationship with.