Flesh that touches any unclean thing shall not be eaten; it shall be burned with fire. (Lev 7:19)
The whole chaper Lev. 11 are about clean things/unclean things that may be or may not be eaten, about one touching dead animal or dead crawling things, or having eaten animal that dies by itself.
LORD:" Say to all the congregation of the people of Israel, You shall be holy; for I the LORD your God am holy.."(Lev. 19:1)
The whole book of Levite contains many rule of cleanliness: about leprosy on human, on our clothes, in our house; about unclean animal or crawling things which one should abstain from touching; about touching dead person, or human bone, or graves; or if someone dies in our house......
(NOTE: I personally think that we should build septic tanks for animal, and teach them to drop their droppings there. The septic tank may also produce methane for cooking, apart from fertilizers.)