You may have been asked by us, or on the faecal egg count (FEC) submission sheet, if you would also like to do a larval culture (LC) on the faecal samples you bring in to us... but, is it necessary?
An LC is when faecal samples are cultured at the lab to see what type of worms are present. They hatch the eggs and count the different types of larvae (e.g. Ostertagia, Trichostrongylus, Haemonchus) and then let us know what percentage each one represents in the sample.
These parasites (and others) lay eggs that are practically the same, so they can’t be differentiated in just a FEC, which simply counts the number of eggs present.
Why would you want to know?
Knowing this level of detail adds further clarification to a FEC test and enables you and your KeyVet to understand more about what is happening on your farm.
When we know which parasites you’re dealing with, we can help you target them more effectively.
When should you get them done?
Parasite populations change over the season, so we recommend that it’s best to do LCs at the start, middle, and end of the season.
We encourage doing them at the same time as a pre-drench FEC test (especially if you are going to do a drench check 7-14 days later), to find out which parasites are present before selecting a drench. Then do them again as part of your post-drench checks to see which parasites have survived.
What do you need for an LC?
Usually we can do an LC with the same samples you bring in for a FEC. Sometimes we may need more samples, but we would let you know. Or, feel free to call your KeyVet to check.
