We have a 9 week old mini dachsund and he keeps biting at his hind quarters. He doesn't have fleas, so what is he doing?

Could be dry skin. Speak to a groomer about what types of conditioners are good for puppies.

It could me the starts of mange as well. A skin scraping will determine that, or if there is anything else going on.

There are many reason, dry skin certainly being one of them.
Allergies are another option, perhaps to a shampoo, carpet cleaner or even food, have you changed his food from what the breeder was feeding?


It could even just be habit, I would recommend a vet check to rule out any medical problems before moving onto behavioural issues.

You can switch foods to see if it is an allergy, and then go from there. Does he chew other parts of his body? His paws or rub his paws on his face? Does he bite at his tale?
Most Veterinary hospitals sell prescription low-allergen diets, as well as soothing shampoos for bathing allergy prone dogs. You usually don't need to bring your dog in for an exam, if they have already treated him or seen him recently. I like feeding Omega oils to my itchy dog.
If it's dry skin try using a humidifier, They work great and you can usually pick them up second hand or relatively cheap for new. I use the vicks one with out the vicks, and I only paid $20 at a drug store for it.
Can I ask what you are using for flea prevention as well as worm prevention? It could also be her anal glands need expressing. :o Usually not that common in puppies. Or hot spots.