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

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VETERINARY PET
Damalinia equi nits on a horse
damalinia-equi-nits-on-a-horse-ketzis-sized
Damalinia equi nits on a horse

    Nits of the horse biting louse, Damalinia equi (also called Werneckiella equi), on its host. Whereas the nits can be readily seen, the presence of a louse (arrow) is revealed only by parting of the hair.

Courtesy of Dr. Sameeh M. Abutarbush.

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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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