I am a veterinarian and also own basenjis. My first dog was a basenji mix and the same thing happened to her after she was spayed. What I found was that she was licking the hair off her abdomen when I was in veterinary school. She was doing that because my schedule changed and I was coming home at a different hour than before the time she was spayed. Once I realized that she was licking, I put a collar on her and the hair started to grow back in slowly. The other thing that could do the same is hypothyroidism. That is what my professor first thought was going on but then I realized that she was likcking and once I got it under control, she was ok.