seems it is any animal, but really who's going to prosecute or find out.
http://www.theargus.co.uk/news/4239...cacy___road_kill/?action=complain&cid=7609148
http://www.theargus.co.uk/news/4239...cacy___road_kill/?action=complain&cid=7609148
However, before picking up road kill, there are certain laws to be aware of. It is illegal to run over an animal and then eat it so, according to the Department for Environment, Food and Rural Affairs, the game animal would belong to the land owner, which would be the Highways Agency. But if the car in front hits the animal, then it is fine for someone else to pick it up and cook.