I had a dog a long time ago and this was never a problem. I think if you're going to adopt a dog you have more immediate concerns to consider such as, do you have time to give a lot of attention to a dog? How do you feel about shedding, dog smells, etc.? Do you mind being licked? Do you mind cleaning up poop? Would you enjoy taking the dog for walks and playing with the dog? These are questions to consider with almost all dogs, whereas anal gland secretions is really only something to think about if it actually comes up with a dog you already have and love. If you have no problem dealing with all of the ordinary gross dog things and you love the dog, you won't have a problem coping with their individual health issues.