Animal skeleton

Animal skeleton: One of our teachers can get a sheep skeleton from someone. The sheep died in a field and the bones are now devoid of any flesh. The teacher wants to know if there is a way in which the skeleton can be cleaned/sterilised so it can be used in the classroom to show the structure of the long bones and the spine etc. I know that we are not allowed to use anything not sourced from a reputable supplier (because of possible disease, fungus and pathogens it may be carrying) but the teacher would like to know if there is something that can be done so she can use it.