Columbia subject headings:
Agriculture--Study and teaching--Information resources.
Animal welfare--Information resources.
Animal welfare--Moral and ethical aspects--Information resources.
Livestock--Behavior--Information resources.
Livestock--Information resources.
Harvard subject headings:
Agriculture--Study and teaching--Information resources.
Animal welfare--Information resources.
Animal welfare--Moral and ethical aspects--Information resources.
Livestock--Behavior--Information resources.
Livestock--Information resources.
Princeton subject headings: