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Anthelmintic (dewormer) resistance


Anthelmintic (dewormer) resistance is a major issue in the small ruminant industry and an emerging problem in other segments of animal agriculture. Drug resistance exists when an anthelmintic treatment fails to reduce fecal egg counts by more than 95 percent. It is inevitable. Severe resistance exists when treatment fails to reduce worm egg counts by more than 60 percent. Currently, there is resistance to all of the anthelmintics used to treat small ruminants (in the US). However, the level of resistance varies by geographic region and individual farm.


Conference proceedings






Last updated 11.03.23.  Links verified 11.03.23.

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