We did have a beagle once. They are notorious hunters, and will take off running when they pick up a scent. That guy was probably using your dog as a hunting dog. But I am glad you did get your dog back. But yes, we did lose our dog one time. He is a black lab that we have had for several years. One day we were out in the yard doing work and had Nash out there with us. We called for Nash and he was not there. We looked around and he was gone. We searched everywhere and talked to neighbors and he was nowhere to be found. He was gone for the rest of the day and night. The next day I called the shelters and sure enough they had Nash. Someone saw him wandering around and they turned him in. Nash did originally have his collar and tags but somehow it was not on him anymore it was lost. So we immediately went to go get him. And we were all very happy to have him home. He never took off again, and I am still not sure why he did it the first time.
