MSD Manual

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

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VETERINARY PET
Transitional ovaries, mare
vernal-transition-ovaries-sertich-sized
Transitional ovaries, mare

    During the vernal transition, the mare's ovaries will enlarge and contain numerous large (>25 mm) follicles but no luteal structures.

Courtesy of Dr. Patricia Sertich.

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The Reproductive Cycle of Horses

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

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