Worms are major threat to poultry production. They impair the health status of the birds leading to reduction in yield and production potential of the affected birds. They cause loss of weight, reduced growth and production, emaciation in poultry birds and even death in severe cases. Worms live in the lining of the birds’ intestine, crop, or the oesophagus; they cause great damage to the digestive tract of the birds which can lead to reduction in feed utilization.
There are basically five worms that threaten the welfare of the birds, they are;
1. Ceca worm
3. Capillaria or threadworm.
4. Tape worm
5. Gape worm
Roundworms are very common in poultry production; they look like spaghetti or noodles with a length of about 1-3m, they live in the intestine or digestive tract of the bird. They infect virtually all poultry birds; chickens, turkeys, ducks and geese in common. There are several types of roundworm e.g. hairworms, threadworms, but the most common is the Large Roundworm. They are very difficult to detect as they do not appear in the birds’ droppings, they can reside in the birds’ system for a very long time. Roundworm infestation starts when the birds eat the roundworm eggs; usually passed out with the droppings of infected birds. After ingestion, the egg incubates in the birds’ digestive tract to form a larva. The larva burrows through the birds intestine to reach the birds’ body to grow further; thus, causing great damage to the birds digestive tract.
The symptoms of round worm infestation are very simple; birds become weak and less active. Heavily infected birds may show droopiness, emaciation and diarrhea. The primary damage is reduction in feed efficiency and feed utilization but death in severe infection. The worm is occasionally found in the egg.
Proper hygiene has to be maintained and proper biosecurity measures have to be adopted. Young birds are most susceptible to round worm infestation; also, birds under stress and birds reared on a deep litter system are also prone to roundworm infestation. Most important is the avoidance of wild birds into the pen; they are good carrier of roundworm
Treatment: Roundworm can be treated with Piperazine and Flubenvet
Syngamus trachea is a round red worm that clings to the trachea of birds and causes the disease known as Gape. The term is used to describe the open-mouth breathing of gapeworm in infected birds. Heavily infected birds usually produce a grunting sound because of difficulty in breathing they experience and may die of suffocation. The worms can easily block the trachea, so they are particularly harmful to young birds.
Gapeworms attach themselves to the trachea (throat) of the birds where they distort breathing resulting in the birds gasping (gaping). Young birds are particularly susceptible and can become infected by sharing space with wild birds such as pheasants.
Gapeworm is often introduced through an intermediate host i.e. earthworms, snails, slugs can all be carriers of tapeworm larvae and once ingested by the bird, they have a life cycle of 14 days. It can also be picked up directly from infected bird coughing out the worms on the ground and then uninfected birds pick it up when scratching the ground.
Treatment: Gapeworm is best prevented by administering a dewormer at fifteen to thirty days interval.
Fenbendazole is also effective in preventing gapeworm.
Tapeworms or cestodes are flattened, ribbon-shaped worms composed of numerous segments or divisions; they love damp environment. Tapeworm varies in size from very small to several inches in length. The head or anterior end is much smaller than the rest of the body.
This worm causes a lot of damage. In young birds, heavy infection results in reduced efficiency and slower growth. All poultry tapeworms apparently spend part of their lives in intermediate hosts and birds become infected after eating the intermediate host. These hosts include; snail, slugs, beetles, ants, grasshoppers, earthworms, housefly etc.
Tapeworms are less common; they attach themselves to the wall of the intestine by submerging their heads in the lining of the intestine. Their eggs are carried by slugs and snails; so, free-ranging birds are more susceptible than indoor birds. Heavy infestation can reduce the bird’s ability to fight other infections.
Reproduction is from segments of the worm that break off and are passed through the birds droppings where it contaminates the ground for other birds to pick up. Tapeworm larvae can be carried by intermediate hosts, most particularly slugs and snails. They are very hard to see with the naked eye and have a life cycle of 6 weeks.
Treatment: Tapeworms can generally prevented by keeping the birds off the infected intermediate host. It can be controlled by regular treatment of the birds with Fenbendazole or Leviamisole.
This parasite (Heterakis gallinae) is found in the ceca of chickens, turkeys and other birds. It causes blackhead in turkey. It produces no observable damage
Treatment: The ceca worm can be effectively treated with Fenbendole.
CAPILARIA OR THREADWORM
There are several species of capillaria that occur in poultry. Capillaria annulata and Capillaria contorta occur in the crop and oesophagus. These may cause thickening and inflammation of the mucosa and hemorrhage. These parasites may become a severe problem in deep litter house. It reduces growth, egg production and fertility in affected birds
Treatment: it can be controlled Hygromycin and Maldane.