False.
FEC have some limitations but if used correctly they are still the most useful diagnostic tool we have available for combating worm related disease.
FECs are also useful to test if your dewormer/drench has worked effectively. We are very interested in monitoring strongyle egg counts and in particular the small strongyle/cyathostome which are the most significant worm for all ages of horses in relation to disease processes. These readily show up in FEC. The Ascarid/roundworm is important to monitor in foals and can also be detected in FECs.
Where FECs fall in to disrepute is when samples are tested whilst the horse is still under the influence of their previous dewormer. It is critical to test in the Egg Reappearance Period (ERP) for the last product used. This differs for each active ingredient. For example if your horse had been treated with Equitak and you submitted a sample five weeks later and obtain a zero result...this means nothing as the optimum time for testing would be greater than 9 weeks after treatment when the adult worms have matured and begun to lay eggs.
Depending on where you send your samples for testing can also affect your FEC data. Most laboratories use a flotation egg counting chamber system which gives results down to 100epg or for extra time and money can give results of 25 to 50EPG. At Worm-Ed we have invested in the latest in FEC technology the "Parasight" which utilises a push button filtration analysis that gives 2.5min results down to 5EPG!
The other limitation of a FEC is that it doesn't give information on tapeworm, bots and pinworm. We have other testing options for these guys. Tapeworm and bots are very readily controlled with most active ingredients if timed correctly. Pinworm has developed some resistance to common drench products and can be diagnosed by observing eggs at the anus and noting tail and dock irritation. Although not life threatening it can be debilitating...especially for showies! If you're experiencing problems with Pinworm let us know! In summary don't be too quick to write off the humble egg count. We have proven systems that will help you get the most out of your FEC and end up saving you time and money!
