Treatment Failure

e.g.:

• animals not weighed correctly
• wide weight range in group
• applicators not calibrated

e.g:

• Drench: e.g. when cattle spit out the drench
• Pour-On:  not absorbed due to a dirty coat, heavy rain after application, or cattle licking each other

The drench used does not target the worm species present e.g. levamisole used to treat inhibited small brown stomach worm (Ostertagia ostertagi).

e.g.:

• giving a drench as a pour-on
• Use of expired products
• Product not prepared correctly (e.g. a combination/ mixture drench not shaken)