my dog chipper

Question
Chipper is a 7 year old dachsund chihuahua. We came home a little while ago and in the time we have been home, he has lost his hind quarters and he keeps opening and closing his mouth like he is smacking his lips froom a meal.  He was not outside, he was in the house

Answer
I am sorry, I never recieved this until today. I don't really know what you mean by he has lost his hindquarters.
Could you please explain this?
If your dog seems to be in distress, however, it is always prudent to get him into the vets as soon as you can.