What food is he eating? What’s the air temp? My boy eats raw meaty bones and meat - it has no brine - and barely drinks water unless he’s had a lot of exercise and it’s hot out. If your dog eats kibble, then he would need to drink water as kibble is very dry and salty. If you’re worried, call your vet.
Hi, how long has pup been home with you? As he's 2 months only a few days I would guess. What are you feeding him on and how often? Is he lively and peeing and pooing?
I just did a quick google search. Hills Science Plan and Royal Canin Puppy both have salt listed in the ingredients. Orijen has dried kelp, but not salt listed. It’s great that the kibble you’ve used doesn’t have added salt. I’m interested to know how you knew the kibble wasn’t salty - did you taste it? My vet once told me he had tasted the joint formula (chondroitin, green lipped mussel) and it was very salty! As a vegetarian, I won’t be tasting my dog’s food! But there’s no reason not to eat it if you eat meat. Here’s a list of sodium content in popular brands: http://vetmed.tufts.edu/wp-content/uploads/reduced_sodium_diet_for_dogs.pdf
