How you can reduce the worm burden - Worming Chickens

Chickens need to be wormed regularly to prevent a build up of worms in their digestive system. Those worms can cause health problems. Keeping chickens in a fixed area as so many of us do, where they are grazing the same piece of ground continually is the worst case scenario as they will be contaminating the ground and picking up worm eggs as they are feeding. Infected hens shed thousands of eggs in their faces onto the ground and so, the problem gets worse.

Worming chickens and other poultry is a straight forward process, but it does help to know a little bit about the worms that are likely to infect your birds and their life-cycle so you can control and manage their numbers, minimizing the worm burden on your flock.

Ectoparasites are found on the outside of your chickens – an example being lice or mites such as Northern Fowl mite. Endoparasites on the other hand are found on the inside of your birds body and are referred to as Helminths in the veterinary world which is a term used to cover a wide range of internal parasites or ‘worms’ as we commonly call them. (Image courtesy of Elanco).

The most important group of worms that concern us are called Nematodes. These worms inhabit various parts of the digestive tract and are listed below. All of the worms listed are part of this group, with the exception of Tapeworms which are part of a group called Cestodes.

The links take you to more information about a particular kind of worm. Perhaps you know which worms are infecting your chickens and want to learn more about them.

The following types of worms can be found in poultry:

Hair worm – Found in the crop, oesophagus, proventriculus and intestine. Also called Capillaria.

Roundworm – Found in the birds digestive system.

Gizzard worm – Found in the gizzard, mainly in geese. A common problem for goslings.

Tapeworm – Fairly uncommon, found in the intestine.

Gape worm – Found in the trachea and lungs.

Caecal worm – Cause little damage but transmit blackhead to Turkeys.

Worming chickens is important because most infections of these worms can cause damage and eventually death. So let’s look at the life-cycle of these worms to understand them a bit more.

The life-cycle of poultry worms

There are two ways worms are commonly picked up by chickens

1. Direct Life-cycle: Worm eggs are expelled from an infected bird in droppings, by the thousands. These eggs sit on the ground surviving for up to a year before being picked up by birds foraging when they are feeding. Large Roundworm, Gizzard worm (that affects geese), Hair worms and Caecal worms follow a direct life-cycle. Hair worms can also follow an indirect life-cycle.

2. Indirect Life-cycle: Worm eggs are expelled from an infected bird by the thousand. This can be in droppings, or in the case of gapeworm that are found in the respiratory system, coughed up. Worm eggs are not infective at this stage. Intermediate hosts, (such as earthworms, slugs, snails and centipedes) will eat these eggs and (you’ve guessed it) your chickens will eat these intermediate hosts and the worm eggs they have ingested and your birds become infected. The larvae hatch inside your chickens and the cycle repeats. Hair worms, Gapeworms and Tapeworms follow an indirect life-cycle although hair worms can also follow a direct life-cycle as well.

Health problems caused by worms

Many health problems that your occur can be related to an infestation of worms of some sort, so it is important to not only worm your birds regularly but manage houses and runs correctly in between worming treatments (more on this later though).

Signs and symptoms of worms

Gaping (gasping for breath) as gapeworms
block the airway.

The signs and symptoms of chickens with worms are listed under each particular type of worm on the individual pages via the links above, but there are many different symptoms and the first question a vet will usually ask when examining a sick bird is “When was he / she last wormed…?” so it is worth ensuring you have a worming routine just to make sure you don’t have problems.gaping chicken.

• The most common symptoms are loss of weight / poor weight gain
• increased feed consumption 
• pale yolk colour
• diarrhoea 
• and in severe cases, anaemia (pale comb and wattles) mortality. 
• In the case of gapeworm, chickens will gasp for breath or ‘gape’ stretching their neck.

Diagnosing worms

Getting a ‘worm egg count’ is the way a vet would diagnose a case of worms. You don’t have to go to your vet to get this done any more, it can be done by submitting some fresh droppings  to a poultry veterinary laboratory service.Worm Count KitThe worm egg count kit contains everything you need to collect and send off the sample to the lab, then the results are sent to you after they have examined the samples under the microscope. 

Damage caused by worms

poultry-wormers-large-roundwormThe damage caused by worms will be in the part of the digestive tract (or respiratory tract in the case of gapeworm) in which the worms live.

Typically, in the gut, worms cause anaemia and haemorrhaging and in sufficient numbers can impact (block) the gut. They not only damage the gut but also take nutrients and their waste releases toxins.

The photograph right below shows an impacted gut, full of roundworms. As you can see, it isn’t very nice.

full of roundworms in small intestine

The next photo shows gapeworms in the trachea (the wind-pipe) of the respiratory system.

gapeworms in the trachea (the wind-pipe) of the respiratory system

The gapeworms are red in colour and Y-shaped.

Good husbandry – preventing worms

Here are some tips to making life more difficult for worms.

• Worm eggs thrive in wet, warm, muddy areas. Remove muddy areas such as those found by pop-holes by creating hard standing or free draining gravel.
• Worm eggs cannot develop when it is very dry, when the temperature is below 10˚C or above 35˚C. Worm chickens as the temperature rises in spring.
• Worm eggs are destroyed by Ultra-violet Light (UV) from the sun. Keep grass short and rotate pasture in the summer if you can to help prevent a build up of worm eggs
• .Keep litter in poultry houses fresh and always ensure it is dry.

Prevention is always easier than cure so follow good husbandry techniques and combined with regular worming (according to the manufacturer’s instructions), you shouldn’t see any problems.