What inferences can be made about what killed the dog and what happens to its body in "There Will Come Soft Rains"?

Apparently having been exposed to radiation, the dog suffers from several conditions, but is able to make it to the front door of his home. 

This dog, who was once large and robust, now appears near death as it stands on the front porch of the house, whining, shivering, and "...gone to bone and covered with sores." It has most likely suffered all the symptoms of radiation exposure: severe vomiting, diarrhea, fever, and dizziness. But, since it is alive and the residents of its home only painted silhouettes on the charred west side of the house, perhaps the dog has been under something when the nuclear explosion occurred.

Once inside, the pitiful dog endures torturous death throes since it must have absorbed a strong dosage of radiation [Absorbed doses of radiation greater than 30 Gy cause neurological damage]. The dog begins to have a seizure, frothing at the mouth and spinning in circles, nipping wildly at its tail until it finally dies. Still, its body lies in the parlor for an hour until the mechanical mice sense decay. Having once sensed this decay, they quickly "hum[med] out as softly as blown gray leaves in an electrical wind." They sweep up the dog and toss it into the incinerator which "glow[ed] suddenly" as "a whirl of sparks" ascend the chimney. Thus, there is no trace of the dog fifteen minutes after the mice dispose of him. It is as though he never existed.