Fecal egg counting


Fecal egg counting is a method to determine the number of worm eggs excreted per gram of feces (EPG). Fecal egg counts (FECs) have many uses in parasite control programs. They can be used to estimate the parasite load in an animal, show changes in the seasonal levels of pasture infection, determine effectiveness of dewormers, and evaluate genetic differences in animals.


Where can I send samples to for fecal egg counting?  

Members of the American Consortium for Small Ruminant Parasite Control who have laboratories are offering affordable ($5 per sample) fecal egg counting for the purpose of genetic improvement through the National Sheep Improvement Program (NSIP) or to determine fecal egg count reductions (to determine dewormer resistance). The results will be provided as numbers only with no interpretation or consultation.    Learn more


Go to list of laboratories that do fecal analysis =>


Genetic Parameters for Fecal Egg Count and Body Weight in Katahdin Lambs. L. Ngere, J. M. Burke1, D.R. Notter, J. Morgan, and J. E. Miller. Journal of Animal Science. [January 2017]


Doing your own research and fecal egg counts. Part 6 in a six part series on worm control in goats. Dr. Steve Hart, Langston University. Originally published in Goat Rancher Magazine [August 2008].

Modified McMaster Egg Counting Technique for Quantitation of Nematode Eggs; Ray M. Kaplan DVM Ph.D., College of Veterinary Medicine, University of Georgia; and James E. Miller DVM Ph.D., School of Veterinary Medicine, Louisiana State University.

Modified McMasters Fecal Egg Counting Technique; by Heather Gannon, North Carolina State University [2013].

Role of fecal egg counts in sheep/goat health. Susan Schoenian, University of Maryland Extension. Timely Topic [2020].

Conference Proceedings

Fecal (Dung) Sampling. Gareth Bath and Jan van Rensburg; W4: What Works With Worms Congress, Pretoria, South Africa [May 2015].


Fecal Egg Counts:  Uses and Limitations; Bob Storey; W4: What Works With Worms Congress, Pretoria, South Africa [May 2015].

External links

Faecal egg counts (interpretation). Vet Lab Manual. New South Wales, Australia.

McMaster Egg Counting Technique; VPTH 603 Veterinary Parasitology; University of Pennsylvania School of Veterinary Medicine.

Online manual for conducting fecal egg counts in goats; Langston University.

Using fecal egg counts in parasite management. Anne Zajac; Virginia-Maryland Regional College of Veterinary Medicine.

Fact Sheets

Fecal egg counting for sheep and goat producers. David Fernandez. Extension Livestock Specialist. University of Arkansas at Pine Bluff. [April 2012].

Using fecal egg counts on your farm; Dahlia O'Brien Ph.D., Virginia State University [October 2019].


What do fecal worm egg counts tell us?; William P. Shulaw, DVM, Extension Veterinarian, Ohio State University Extension, Veterinary Medicine [2011].

Sources of McMaster Slides

Chalex Corporation
P.O. Box 187
Wallowa, OR 97885


FEC Source
(503) 747-8378

Focal Point
TE (Eddy) Krecek 
krecek@icon.co.za; eddy@mcmaster.co.za 

Hausser Scientific
935 Horsham Road, Suite C
Horsham, PA 19044
(215) 675-7769


Fecal egg counting primer. Weekly Worm Webinars. Dr. Dahlia O'Brien [April 2020].

How and why to do sheep and goat fecal egg counting. Northeast Small Ruminant Parasite Control Program [February 2015].

Microscope crash course for fecal egg counting. Northeast Small Ruminant Parasite Control Program [February 2015].