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Merck Manual
Veterinary Manual
The trusted provider of veterinary information since 1955

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VETERINARY PET
Estrous mare
estrus-mare-sertich-sized
Estrous mare

    Typically, a mare in estrus will abduct the hindlegs, raise the tail, evert the vulvar lips, and urinate in the presence of a stallion.

Courtesy of Dr. Patricia Sertich.

In these topics
The Reproductive Cycle of Horses

Merck & Co., Inc., Rahway, NJ, USA (known as MSD outside of the US and Canada) is dedicated to using the power of leading-edge science to save and improve lives around the world.  The Merck Veterinary Manual was first published in 1955 as a service to the community.  The legacy of this great resource continues as the Merck Veterinary Manual in the US and Canada and the MSD Vet Manual outside of North America.

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