Is it permissible for a Muslim to rescue a cow left by disbelievers to die in a river, then slaughter it according to Islamic rites, and eat it, sell it, or distribute it as charity?

What some disbelievers do by offering sacrifices and slaughtered animals to their deities is disbelief and misguidance. Allah and His Messenger have forbidden the animals slaughtered in the name of other than Allah the Almighty, as He says: (Forbidden to you are carrion, and blood, and the flesh of swine, and that which has been invoked other than Allah thereon) Al-Ma'idah/3. This prohibition is specific to what was slaughtered in the name of other than Allah, not what has not yet been slaughtered. If the animal prepared for slaughter in the name of other than Allah is caught before its death and slaughtered according to Islamic law, it becomes lawful, as Allah the Almighty says: (except that which you [yourselves] slaughter).

If disbelievers prepare a cow to offer it for slaughter to their deities and a Muslim is able to save it, he may slaughter it according to Islamic law and eat it, sell it, or give it in charity. By doing so, he would have saved it and thwarted their intention. This cow is considered to be like stray property that may be taken.