Worm Egg Counts

Worming chickens can be a very confusing subject! We’re often guided by our experience with our cats and dogs, where we worm every month regardless. However, more evidence is emerging about the threat of resistant worms and treatments that no longer work; we’ve already seen this with antibiotics and resistant bacteria. It doesn't make sense to ignore the threat or resistance when it comes to parasites too.

There are several types of worms carried by chickens, and our treatment approach should be determined by which types of worms are present and how many. If we just treat for worms every 3 or 4 months, then we’ve no idea what’s going on! Some worms pose a greater risk to your bird’s health than others (such as Calliparia) and some may require more frequent treatment or with different treatments (potentially prescription drugs) … or they may not need to be treated at all! This is the beauty of a worm egg count (WEC): it helps us make informed decisions and tailor the treatment plan to meet our birds' needs.

How do chickens become infected with worms?

Contaminated ground: Chickens can pick up parasitic worm eggs by pecking around at the ground. The ground becomes contaminated from infected birds passing worm eggs in their faeces. It's a cycle of birds accidentally picking up worm eggs, the eggs hatch in the bird, the hatched worms develop into egg-producing adults which live in the birds(gut or airway), and they produce eggs which are passed out in the bird's faeces, further contaminating the ground.

New birds: If you take on new birds, make sure they are quarantined and sampled for a WEC before introducing them to your resident birds; there's a risk of them introducing a worm infection and contaminating your ground. Once the ground is contaminated with worm eggs, it can be very difficult to clean up.

Insects: Another route of infection is through eating infected insects. Bettles, earthworms, etc., can pick up and carry the parasitic worm eggs (intermediate hosts), so when the chicken eats the insect, they eat the parasitic worm egg too!

What’s the alternative to routine worming?

Start with worm egg count testing. Kits are available to buy online. All you need to do is collect up a sample of your birds' faeces, pop it in the container provided in the kit and post it to the testing lab.

What do the lab do with the sample?

Upon receipt, the lab will test your sample to determine whether worm eggs are present. They can tell what types of worms are present by identifying the different eggs and they will also count the eggs. The only exception is tape worm eggs, which usually dissolve and are difficult to see on WEC, but they can be seen by eye in faeces!

Ok, so I’ve got the results, what now?

The worm egg count results should come with instructions on what to do next. If the sample has a very low worm egg count, then you may not need to worm, but retest in about 2 or 3 months to monitor.

If there are high worm egg counts that warrant treatment, seek advice from a vet or a suitably qualified person (SQP) who can recommend appropriate treatments. I would recommend a WEC again 3-4 weeks after treatment to check the re-infection level. Assuming your ground is contaminated, and your birds are at risk of picking up a worm infection again. It may be necessary for more frequent worming and a treatment schedule to keep the infection burden under control.

Chicken clinic video calls or home visits are available if you’d like tailored advice on managing worm infestations.