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

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VETERINARY PET
Sinus with Oestrus ovis third-stage larvae
sinus-with-oestrus-ovis-third-stage-larvae-mackay-sized
Sinus with Oestrus ovis third-stage larvae

    Gross pathology photograph of a cross-section of a sheep's head with multiple Oestrus ovis third-stage larvae in the nasal and paranasal sinuses.

Courtesy of Dr. Raffaele Roncalli.

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Sheep Nasal Bot Myiasis

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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