Not all vets specialize in toy breeds. I've had Chihuahuas for 20yrs and we do a slow wean from 7-8wks. Listen to what your vet tells you, then do your own research and get a second and third opinion. Chihuahua puppies shouldn't be sold until they are at least 10wks. The only reason to wean them early would be to sell them early. Too many puppies die that way. Puppies are supposed to continue to nurse even with teeth.
You should take ground up puppy food and add warm water, let it sit and let momma outside to potty. Give the puppies 45min or so to eat it before letting momma back in to clean the bowl! They should be off mom completely by the age of 8wks then you should watch them for 2 weeks for signs of hypo before letting them go to their new homes.
You should take ground up puppy food and add warm water, let it sit and let momma outside to potty. Give the puppies 45min or so to eat it before letting momma back in to clean the bowl! They should be off mom completely by the age of 8wks then you should watch them for 2 weeks for signs of hypo before letting them go to their new homes.