Columbia subject headings:
Animal welfare--Law and legislation--United States.
Horse industry--Law and legislation--United States.
Horses--Law and legislation--United States.
Slaughtering and slaughter-houses--Law and legislation--United States.
Harvard subject headings:
Animal welfare--Law and legislation--United States.
Horse industry--Law and legislation--United States.
Horses--Law and legislation--United States.
Slaughtering and slaughter-houses--Law and legislation--United States.
Princeton subject headings:
Animal welfare--Law and legislation--United States.
Horse industry--Law and legislation--United States.
Horses--Law and legislation--United States.
Slaughtering and slaughter-houses--Law and legislation--United States.