Parasitic Diseases of Poultry: Symptoms, Control, and Treatments

June 3, 2023June 22, 2023 Agric4Profits

Parasitic diseases are those type of diseases which are caused by parasites. A disease is an unhealthy or abnormal physical state and/or appearance. It can be caused by living organisms (infectious agents) or faulty environments due to poor management. Chickens, like human beings, are subjected to many diseases and parasites.

There are even some poultry diseases with the same names like cholera, pox, typhoid, hepatitis, etc. Chickens are also known to suffer from internal and external parasites. Some poultry diseases and parasites can be prevented while others cannot be prevented.

Some cannot be controlled and cause death when contracted; others can be isolated and controlled. Some are present in the country and others are from foreign sources.

Unless diseases and parasites are accurately identified and prevented or controlled, they can cause huge losses of chickens and consequently loss of money.

The key is to prevent rather than to control. Poultry farmers need to be familiar with the causes and symptoms of the various common poultry diseases in order to plan an effective control program.

Parasitic Diseases of Poultry

Parasites, both internal and external are common in the tropics. Both can weaken the bird and in certain cases may be a secondary host for other diseases. External parasites may cause considerable loss to the poultry.

They irritate poultry and sometimes kill them. They cause discomfort due to irritation, loss of plumage gradually leads to deterioration in the health of the flock and reduction in egg production among layers or retarded growth among the young birds.

The birds will be pre-occupied with scratching and do not feed well leading to poor performance. External parasites can also serve as rectors transmitting diseases from one bird to another.

Besides the protozoan parasite Trichomonas gallinae in pigeons, the most important internal parasites in poultry are the helminths. Some examples of parasitic diseases are coccidiosis, ascariasis, syngamosis tapeworm infection, and lice infestation.

1. Coccidiosis

This disease of poultry is caused by a protozoan parasite that resides in the walls of the chicken’s intestine and will cause death at any age. Coccidiosis is very common and is probably the biggest killer of chickens.

It is said to be caused by 8 to 9 distinct species of protozoa of the genus Eimeria. It is spread to chickens particularly up to the age of 12 weeks through contaminated food, water, or litter.

Each species of Eimeria attacks a different portion of the intestines or caeca and it is particularly prevalent in chickens that are kept intensively which have the maximum possibility of taking up the disease from their fellow chickens.

Symptoms – Droppings are watery and greenish or brown often containing blood. The affected birds lose appetite, their feathers become ruffled and soiled. Combs are pale and they tend to huddle together in corners. Their heads pull back into their body with their eyes usually kept closed.

Control – Chickens should be fed with medicated (coccidiostat mixed feed) feed at all times. Keep the litter dry and loose and keep your chicks in thoroughly disinfected pens on their arrival.

Coccidiostas like Amprolium or Deccox may be used as preventive drugs for the first 8 weeks. Prevent the fecal contamination of the feed and the drinking water. The safest way to avoid coccidiosis is to raise chickens on wire floors where the feces are passed out of reach.

Treatment – Add to the drinking water a coccidiostat. Isolate sick birds and when the attack dies down disinfect litter and sterilize pens.

2. Ascariasis

This disease is caused by Ascaridia galli (roundworms) which is common among local chicken and other poultry species which are not well managed. The roundworms occupy the small intestine, are white or whitish yellow, and are 2.5-10cm long.

The worms and eggs are frequently passed in droppings. The eggs develop into the infective stage in 10 to 12 days under favorable temperature and moisture conditions, and hatch either in the proventriculus or in the duodenum.

After hatching, the young larvae line free in the lumen of the posterior duodenum for the first 9 days, and then penetrate the mucosa and cause hemorrhages.

Symptoms – The most observed symptom is catarrhal or haemorhogical enteritis among young birds. Adults are usually symptom

less except for loss of conditions. Worms can also be observed in droppings. There could also be persistent diarrhea.

Control – Young and adult flocks should not be reared in the same house.

Treatment – Administer piperazine to the birds and also treat the deep litter with the same drug, once in two months. Furthermore, maintain high hygienic standards.

3. Syngamosis

This disease is caused by a parasite Syngamus trachea (gape worm) which uses earthworm as a transport host. The worm is found in the lower part of the windpipe and sometimes in smaller air passages of fowls usually not less than 6 weeks of age.

Symptoms – Affected birds often shake their heads and gasp for air. Death also results from suffocation.

Control – This is by maintaining the good hygienic conditions of the poultry unit and destruction of the transport host.

Treatment – Infected birds can be treated with anthelminths like thiabendazole.

4. Tapeworm Infection

The most common and economically important tapeworms (cestodes) are Darainea proglothina, Raillietina spp., Amoebotaenia spencides, and Choamotaenia infundibulum.

Part of the life cycle of these worms occurs in intermediate hosts such as snails and earthworms, which when eaten by fowls expose them, to infection.

Symptoms – These are usually observed among young birds and include loss of appetite, droopiness, thirst, and emaciation.

Control – The intermediate hosts should be attacked by the use of molluscicides and insecticides.

Treatment– Infected chicken should be treated with anthelminthic. Also, a good hygienic environment should be maintained.

5. Lice Infection

Lice are the most common external parasite. Lice differ from mites and ticks because they spend their entire life cycle on the body of the bird.

There are two types of lice attacking animals namely blood sucking and biting lice.

Only the biting lice attack chickens and can be found at different locations on the body of the fowl.

Lice are three types:

Body lice are found around the vent and tail.
Head lice which are found around the head and neck regions
Shaft lice are found around the shaft of the feathers.

Lice reproduce rapidly at about 30,000 per female and can live up to 3 months. They spread by direct contact and die once they leave the chickens. They are about 3mm long, oval shaped, and grey or yellow in color.

Symptoms – General ill health, constant irritation, scabs, ruffled feathers, slow weight gain, decreased egg production, and death in some smaller chickens.

Control – The birds should be inspected regularly for the presence of any external parasite. Prevent overcrowding and poor hygiene.

The nests should be kept clean and if the birds roost at night, perches should be painted with nicotine sulphate, and creosote placed in the cracks and joints of the roost.

Treatment – This can be achieved by spraying the birds with malathion solution or by dusting individual chickens with pyrethrins or malathion powder. In the case of deep litter systems, the litter and all equipment except the feeders and waterers should be sprayed and dusted.

6. Tick Infection

Ticks are blood-sucking organisms and are in various forms mainly flat, egg-shaped, disc-shaped. They also carry diseases such as spirochetosis. They are normally found in hot dry areas and they spend part of their life cycle in cracks in walls and roofs and other equipment made of word.

Symptoms – These are loss of appetite and weight, and possibly anemia.

Control – Keep equipment clean and avoid the use of wood in equipment such as feeders and nesting boxes. Also, avoid crevices in the poultry houses where ticks can hide.

Treatment – This can be done by spraying the birds with malathion solution or by dusting the chicken with pyrethrins or malathion powder as in lice.

7. Mite Infection

Mites are very small and almost invisible. There are many known species. Some stay on the chickens while others attack only at night and hide in the woodwork and litter during the day.

Symptoms – Symptoms are specific to species of mites. Scaly leg mites make the birds lame, and the legs swell, and appear scaly, and encrusted.

Red mites are nocturnal. They cause loss of weight and decrease in egg production and may cause anemia. Dephiming mites attack the base of feathers and birds pull out their feathers to relieve itching, hence their name.

Control– This is the same as for ticks.

Treatment – There is no treatment for the scaly leg mite except for culling infected birds. For other mites, the treat is the same as for lice and ticks.