sheep bot fly

insect

Also known as: Oestrus ovis

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Last updated

July 13, 2026

Quick Summary

The sheep bot fly, also known as the sheep nasal fly or sheep nostril fly, is an insect belonging to the fly order, Diptera. These flies are beelike in appearance and hairy, but they lack bristles. The larvae of the sheep bot fly are parasitic and live in the nasal cavities of sheep, and occasionally goats.12

When the adult fly deposits larvae in the nostrils of sheep, it can cause a nervous condition known as blind staggers. Members of this subfamily are known for their swift flight, capable of speeds between 12 to 19 miles per hour.2

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bot fly
…bot flies (Cephenemyia) and the sheep bot fly (Oestrus ovis). Active larvae, deposited in the nostrils of sheep, often cause a nervous condition called blind staggers. Members of Oestrinae are noted for their swift flying; they are capable of moving at 20–30 km (about 12–19 miles) per hour.
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…bot flies (Cephenemyia) and the sheep bot fly (Oestrus ovis). Active larvae, deposited in the nostrils of sheep, often cause a nervous condition called blind staggers. Members of Oestrinae are noted for their swift flying; they are capable of moving at 20–30 km (about 12–19 miles) per hour.
Read More