Alpacas are not sheep (or cows!), and that includes their resistance to parasites! Alpacas come from an arid climate where parasites do not pose a problem. As a consequence they have little natural immunity to them, meaning that a parasite burden that is not problematic to a sheep can cause severe clinical disease in an alpaca.
To ensure we accurately gauge the number of worms that an alpaca is infected with, we need to do a faecal egg count to see how many eggs these worms are laying. The method used to do this in sheep (McMasters) is not sensitive enough as it only detects to the nearest 100 eggs per gram. The method we use in alpacas (Modified Stolls) detects eggs to the nearest 5 per gram meaning that we can give you a much more accurate picture of the worm infestation that an alpaca has.
The added benefit of doing a modified stolls FEC is that we can detect the dreaded Eimeria macusaniensis. This is a highly pathogenic (disease-causing) coccidia which is always significant when detected and requires prompt treatment, especially if there are pregnant dams or cria grazing the pasture.