9 C.F.R. § 91.9 – Ports.

(a) Except as provided in paragraph (b) of this section, livestock exported by air or sea may be exported only through ports designated as ports of embarkation by the Administrator. Any port that has an export inspection facility that meets the requirements of § 91.10 permanently associated with it is designated as a port of embarkation. The Program Handbook contains a list of designated ports of embarkation. A list may also be obtained from a Veterinary Services area office. Information on area offices is available on APHIS' import-export Web site (http://www.aphis.usda.gov/import_export/index.shtml).
(b) The Administrator may approve other ports for the exportation of livestock on a temporary basis with the concurrence of the port director. The Administrator will grant such temporary approvals only for a specific shipment of livestock, and only if pre-export inspection of that shipment has occurred at an export isolation facility or an export inspection facility not associated with the port of embarkation, as provided in § 91.7.
(c) Temporarily approved ports of embarkation will not be added to the list of designated ports of embarkation and are only approved for the time period and shipment conditions specified by APHIS at the time of approval.
(Approved by the Office of Management and Budget under control number 0579-0432)