Simple solutions to common problems veterinarians and technicians encounter when performing FECs
Fecal egg counts (FECs) are the basis of modern equine parasite control programmes. However, reliably counting parasite eggs for the information you need to make smart deworming decisions can be frustrating. In this article Martin Nielsen, DVM, PhD, Dipl. ACVM, EVPC, Schleickger Professor of Equine Infectious Diseases at the Gluck Equine Research Center at the University of Kentucky, in Lexington, provides solutions to seven common problems that equine practitioners and technicians encounter when performing FECs.
Problem: My clients don’t understand the purpose of FECs.
The solution: See the frequently updated AAEP Internal Parasite Control Guidelines to hone your basic knowledge of internal parasites.
Nielsen co-authored the AAEP Guidelines, which outline the main objectives of FECs:
- Perform fecal egg reduction tests (FECRTs) to monitor worm resistance (deworming) among both cyathostomins and ascarids (Parascaris spp).
- Identification of animals requiring anthelmintic treatment as part of a targeted anthelmintic treatment protocol. Surveillance-based control systems eliminate rote deworming, with the goal of maintaining effective chemical anthelmintic drugs.
- Identify the presence of ascarid eggs in young cattle and dewormed animals when indicated with an appropriate anthelmintic.
Perform FECs at least twice a year on all adult horses. This allows you to classify horses based on the level of egg shedding, because not all horses lay eggs of parasites to the same degree. Research shows that a small percentage of horses, called “high sheds,” are responsible for putting out the bulk of the eggs on the farm. This is the 80/20 rule: Twenty percent of the horses on a farm lay 80 percent of their eggs.
Low sacks contain less than 200 eggs per gram (EPG) of faeces, while medium and high sacs contain more than 200 and 500-1000 EPG, respectively.
“The main objective of the FEC is to identify low and high irregularities,” says Nielsen. “The average shears between 200 and 500 EPG is not nearly as important.”
Problem: I don’t know which horses to euthanize based on the FEC.
The solution: Focus on moderate/high splinters at appropriate times of the year.
Deworming only on high stairs helps reduce selection pressure to fight worms. Most horses usually need to be dewormed once or twice a year, but older horses often need more worms.
This story requires a subscription to the horse magazine.
Current magazine subscribers can click here And keep reading.