Places such as road side zoos or petting exhibits for hire
(ie.,children's parties) have to have a license to conduct business
in a particular area.

http://www.ehow.com/how_4431202_get-permits-petting-zoo.html

and at the USDA site:
<http://search.usda.gov/search?q=license+petting+zoo&btnG=Search&output=xml_no_dtd&proxystylesheet=default_frontend&ud=1&site=APHIS_MAIN>

You can ask to see a copy of this license of the business hosting
the zoo or the zoo itself. If none is displayed or available, the
jurisdiction of the event or of the address of the zoo (business card)
will tell you where you can lodge a complaint.

[Posted in FML 7122]