To keep cattle healthy, producers need to know which parasites are present. A targeted deworming program is the best way to control them and prevent resistance.
How to Test for Parasites
A good testing program includes:
- Fecal Egg Counts (FEC): Measures how many parasite eggs are in an animal’s feces.
- Coproculture: Hatches larvae in a lab to identify parasite species.
Identifying the type and number of parasites is important because different species cause different problems. For example:
- Brown stomach worms lay about 200 eggs per day.
- Barber pole worms lay up to 10,000 eggs per day.
This means an FEC of 50 eggs per gram could be a minor issue or a major one, depending on which parasite is present.
Checking If Treatment Works
To see if deworming is effective, a Fecal Egg Count Reduction Test (FECRT) is used. This involves:
- Collecting a fecal sample before treatment.
- Treating the animal.
- Collecting another sample after:
- 7-10 days (for white dewormers)
- 14-21 days (for macrocyclic lactones)
If the egg count drops by 90% or more, the treatment worked. If it drops by less than 90%, the parasites might be developing resistance.
When to Deworm Cattle
Parasites can’t be wiped out completely, but they should be kept at a manageable level. Experts recommend deworming:
- Cattle with a body condition score of 4 or lower, as they need all available nutrients.
- All cattle under 3 years old, since they typically carry more parasites.
Deworming young stock helps reduce pasture contamination, which lowers infection rates in the next generation.
By testing regularly and using a strategic deworming plan, producers can improve herd health and boost productivity.
