Can we become unclean by a cow?

Answer From The Annual Reading Schedule - Week 24 Notes For Leviticus: Yes – If the cow dies without having been slaughtered (e.g. it dies of a disease, old age, wild beast attacks, etc.) (Leviticus 11:39-40). This applies to all clean animals that are ours for food. This is why when getting a leather product or something else, it would also be good to research, if possible if we can ascertain if the animal was certainly slaughtered (in most cases I would guess they are, but it doesn't hurt to research if verification can be made). We also see later in Deuteronomy 14:21 we are actually commanded to not eat animals that die of itself – meaning it dies and was not actually slaughtered. This is obviously referring to clean animals since we would never eat an unclean animal anyhow, let alone touch it or give it to someone else to eat since it is an abomination.