I use a rotation of dewormers and the most recent was Equimax which protects againts bots. Does this mean that I still need to remove the eggs from his coat or will the larvae die as soon as they bite him/start to burrow? If I am diligent about removing the eggs from his coat, will deworming with a boticide make any big impact?
Yes, remove them. Pasture maintenance and things like removing the bot eggs are essential, since all a paste dewormer can do is kill what is already present in the intestinal tract. Ingestion of new parasites continues constantly. The bot larvae already in the horse have been treated….but the eggs on his legs have not. Dewormers don’t offer any ongoing protection, so the day after they are administered, whatever parasites the horse is ingesting are active and growing again inside of the horse.
It’s always a good idea to prevent any type of worm infestation. I would recommend going ahead and removing the eggs from the coat. The wormer would only kill the larvae that were present at time of dosage.