The Capillaria threat to hens

Intestinal worms are the most common internal parasite affecting chickens, and free-range birds are at constant risk of developing an infestation due to their exposure to their own faeces in both their indoor and outdoor environment.

Whilst a heavy burden of any of the four main species of worms can lead to disease and, at worst, death, one species carries a greater risk severe problems than the others, namely the Capillaria species.

Because of their abundance in the environment, worms are practically inevitable¹, as worm eggs or larvae are ingested straight from the ground², with birds consuming contaminated droppings, soil, grass or even feed¹.

Also known as the “hairworm”, Capillaria are found in the stomach and intestines of chickens³. At around 1.5cm long, they are the smallest species affecting chickens, and are almost invisible to the naked eye due to their thread-like appearance². However, despite their small size, these worms are often considered the most dangerous³, as even small burdens can be fatal for birds⁴. 

Signs that may be seen as a result of infection with Capillaria are varied but can include reduced egg production, weight loss, reduced food intake⁴, diarrhoea, anaemia and death³. Chickens can also become stressed and look generally unwell, becoming dull and hunched³.

Like all intestinal worm species, the Capillaria worm’s lifecycle starts with an egg passed out in faces, which is ingested and then goes through several larval stages within the bird before becoming an adult, which can produce eggs and start the cycle again. In favourable conditions, this lifecycle can take just a matter of a few weeks, and it should be assumed that there are lifecycle stages present in birds at any one time. The ability to control all of these different life stages is key to getting on top of an infestation, something that not all of the products available can claim to do. 

Thankfully, Capillaria can be effectively prevented and treated, but as mentioned above, not all wormers are equally effective or licensed to do so. Flubenvet™ is the only wormer licenced to treat all life stages of the major worm species affecting poultry⁵, including Capillaria, without needing to increase the dose rate to do so. Flubenvet has a zero day withdrawal for chicken eggs, so production can continue during and after treatment. In addition, it has no effect on egg production⁵, nor are there any known adverse effects or special precautions⁵ to consider, when used at the recommended dose rate, making it an ideal complete wormer for your flock. When worming your flock, always check that the product used treats all lifecycle stages and is specifically licensed to treat Capillaria as otherwise birds could be left at risk.