Days ago I went to walk with my dog (4 years and no breed) , as the place was very quiet (it was a field) I decided to release her from her leash and she started to walk freely but next to me. Later my dog found a corpse of a dead animal, I think it was an opossum, and she started wallowing with that corpse, that is, it seemed like she wanted to have that rotten smell of the animal in all her fur, I was surprised of what was doing, I do not understand why she did that.
Is there an explanation for that behaviour ?