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External Parasite and Vector Control Guidelines

Download the entire document here.

Commonly used strategies for external parasite control in horses have not changed significantly in recent years. This document is intended to provide practitioners withTick current information regarding the control of Ticks, Flies, Lice, Mites and Mosquitos as well as pertinent information on the life cycles, biology and basic terminology used when discussing these parasites. Where appropriate, we have included brief information regarding the diseases for which a specific parasite may serve as the vector.

It is important to keep in mind that the information contained within these guidelines are suggestions; there are many variations of these suggested programs that will still meet the same goals and follow the same principles.

There are a number of product treatment charts included in this information. It should be noted that only those products which are approved for use in horses have been included.

External Parasite & Vector Control Guidelines Task Force: Drs. Dennis French (Chairman), Thomas Craig, Jerry Hogsette, Jr., Angela Pelzel-McCluskey, Linda Mittel, Kenton Morgan, David Pugh, and Wendy Vaala.


AAEP guidelines are created simply to serve as guidelines for the practitioner and the equine industry. As such, they do not have the force of law. All guidelines issued by the AAEP should be regarded as one of several tools or resources, which a practitioner may take into consideration in the context of his or her practice. All practitioners are encouraged first and foremost to understand and comply with the laws, regulations and standard of care of their appropriate jurisdiction. While guidelines are intended to promote a standard for veterinary practice, lack of adherence to any specific AAEP guideline does not constitute grounds for disciplinary action. The AAEP can exercise disciplinary action only in connection with its own members and its action is limited to denial of membership in the AAEP. The AAEP shall have no liability whatsoever for any of its guidelines. A subcommittee of the AAEP board reviews all of the AAEP guidelines and position statements every five years. Any proposed revisions are approved by a vote of the full board. Dates listed in parenthesis indicate either the date the original statement was approved or the approval date of the latest revision.

© Copyright AAEP 2016