Over Christmas we adopted a rescue dog while visiting family. The day after adopting her she was very sick and we spoiled her. Our other dog who is 4 yrs old was fine during this time. We went back home after Christmas and the dog that we had (the 4 yr old) stopped eating. He will eat people food and dog treats but not his own food. Should I be worried that he is sick? Or is he just reacting to the new dog?

The odds are he is just reacting to the new dog. Still, he could have picked up whatever the new dog had. A vet check is never wrong in a case like this. Discuss the dog not eating and whether it can afford to lose much weight. Read through https://www.askmehelpdesk.com/dogs/i...tml#post254171 It wouldn't hurt most dogs to lose a little weight.

Unless the vet says otherwise, cut out the people food and treats, and follow the routine in the sticky. Give the old dog plenty of attention, petting, brushing, walks, fetch, whatever it likes best. If it continues to lose weight, get back with the vet. Tempting the dog with rich food is nearly always the wrong thing to do.

Better leadership helps to. If the top dog decides to add a pack member, it is the duty of the lower ranking ones to accept it. The key to most behavior problems is approaching things using the dog's natural instincts. Dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog. Life is much easier if the 2 legged pack members outrank the 4 legged ones. You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat. Start at Raising Your Dog with the Monks of New Skete For more on being top dog, see Establishing and Keeping Alpha Position, Letting your dog know you are the boss

So the old dog went to the vet. The vet said he thought he has a stomach virus. Now we have to give him something to ease his stomach and antibiotics. Hopefully this works.