Parasites that affect chickens externally and internally. The damages may sometimes go unnoticed by in most instances, these organisms usually cause devastating health effects and sometimes death.
Some of the common chicken parasites and diseases that affect chickens include:
External Parasites
External poultry parasites don’t live in the host but they feed on them from the outside. Some are large and can be seen with naked eyes while others are extremely tiny. External parasites usually feed on the poultry’s blood, dead skin, and the feather shaft’s debris among others.
Red Mite
Signs and illness development
Red mites can result in a wide range of symptoms in poultry. The most common ones include:
- Skin irritation
- Anemia (blood loss)
- Restlessness
- Weakness
- Dullness
Diagnosis
Healthy chickens usually have bright red combs. If your suspect your chickens have been infected with red mites, check if the combs have the wattle colour.
Treatment, prevention, and control
You can treat these parasites by administering Exzolt. Simply put it in the poultry’s drinking water. To prevent and control their spread, use natural alternatives such as dust baths, keeping the coop clean, and detergent-based products such as Smite.
Zoonotic Potential
Red mite doesn’t just affect poultry. They can also bite human beings, resulting in dermatitis and itching.
Sources: Moredun Org and Farmers Weekly
Northern Fowl Mite (The chicken vent parasite / Ornithonyssus sylviarum)
Signs and illness development
This is a temporary bird parasite whose symptoms include:
- Scaly legs and skin
- Broken feathers
- Baldness around the neck
Diagnosis
A quick way to diagnose the Northern Fowl Mite is by checking the poultry’s comb. This parasite usually makes the comb pale and results in vent-feathers that are dirty-looking.
Treatment, prevention, and control
After positively diagnosing your poultry, you should administer treatment by spraying or dusting them with an insecticide. You can prevent the infestation by ensuring that the coop is clean. The best control techniques usually spraying garlic solution or essential oil solution around the coop and directly on the kitchen.
Zoonotic potential
Northern fowl mite has the potential of affecting human beings resulting in:
- Skin lesions
- Allergic reactions
- Dermatitis
- Pruritus
Sources: Science Direct
Common chicken louse (Monopod gallinae)
Signs and illness development
Symptoms of Common Chicken Lice include:
- Constant fatigue accompanied by signs of sluggishness and withdrawal
- Constantly dirty vent
- Pale combs and wattles
- Itchiness
- Drooping wings
- A significant drop in the production of eggs
Diagnosis
To diagnose this condition, check the combs, vent, and wings. Common Chicken Lice usually results in pale combs with wattles due to anaemia. If the vent is constantly dirt with specks or the wings have drooped, then your chicken is probably unwell.
Treatment, prevention, and control
A common treatment option involves the use of food-grade diatomaceous earth for dusting. Besides that, ensure that you feed your chicken iron due to deficiency caused by anaemia. To control the spread of Common Chicken Lice, quarantine infected chickens since these parasites usually spread very quickly. Besides that, frequently treat your chicken with the appropriate dust baths
Zoonotic potential
Just like the other mites, Common chicken lice don’t live in human beings. However, it usually causes bites that leave itchy red marks.
Sources: Hobby Farms and The Happy Chicken Coop
Scaly leg mite (Cnemidocoptes mutans)
These chicken parasites normally affect the chickens’ feet resulting in significant deformities.
Signs and illness development
- Lameness and deformities
- Pain and loss of toes
- Thick and crusty-looking chicken legs and feet with scabby
Diagnosis
Chickens normally have scales on their feet but the scales are smooth and usually lie flat. Diagnosis of Scaly Leg Mites in chicken involves checking the legs for rough and uneven scales. In some instances, the scales may grow thick and start to peel up.
Treatment, prevention, and control
Home-made treatment usually involves soaking the chicken’s feet in warm and soapy water in order to loosen the dead scales for easier removal. When you soak the chicken’s feet, the mites will be killed by suffocation. In case the symptoms are severe, then a veterinarian can recommend Ivermectin.
To prevent and control the spread of scaly leg mites, ensure that the coop is clean and it’s regularly disinfected. It’s also important to frequently give your chickens dust baths to minimize their chances of suffering from parasitic infections.
Zoonotic potential
Scaly leg mites can be passed to human beings and they can even set up their human infestation. Symptoms can include itchy skin and scaly feet. You can use home remedies for treatment by soaking your feet in warm water, exfoliating the dead scales, and then using petroleum jelly to lather the area.
Sources: The Happy Chicken Coop and The Chicken Chick
Depluming mite (Cnemidocoptes gallinae)
Signs and illness development
- Bald patches and tattered feathers as a result of the bird plucking its own feathers
- Intense irritation resulting in skin damage and oozing fluid
- Constant preening
- Weight loss
- Scaly crusty skin and broken feathers
Diagnosis
If you notice bird cannibalism, then your chickens probably have Depluming mites. These parasites lead to the constant feeling of itchiness hence your birds may end up pulling down their own feathers as well. The irritation is usually intense, causing the chicken to lose weight.
Treatment, prevention, and control
Common treatment options usually involve the use of sulfur baths. You can conveniently find this natural product in most pet stores. Besides that, you can also use Ivermectin treatment but only if a veterinarian gives you the prescription. To control the spread of Depluming Mites, isolate the birds that are infested.
Zoonotic potential
They can affect humans leading to itchiness. They are non-borrowing mites that can bite human beings.
Source: Parasitipedia
Fowl ticks (Argas persicus)
Signs and illness development
- A reduction in the production of eggs
- Red spots on the chickens’ skin
- Sudden uneasiness during roosting
- Weight loss and toxemia
- Anaemia and paralysis
Diagnosis
Birds that are infested with fowl ticks tend to suddenly get agitated when they are supposed to roost. Besides that, you might notice that they are reluctant to get inside the coop since the area is tick-infested.
Check the area below the roosts, especially places with cracks, if there are dark or burgundy-coloured spots.
Treatment, prevention, and control
You can treat fowl ticks with Malathion, a type of powder or spray treatment. Simply apply it to all the components found in the coop. besides that, FGDEs and poultry protectors are great. The control and prevention technique that you can apply includes keeping the coop clean at all times.
Furthermore, make it a habit to use organic repellent just before your chickens get out to free range. Eliminate tall grasses and bushes in your backyard. Don’t forget to add garlic powder in the chicken’ feed since it helps to deter pests such as ticks from burrowing or feeding on the chicken’s skin.
Zoonotic potential
Fowl ticks chicken parasites cause severe skin irritation in human beings. These ticks have painful bites with toxic after-effects. While such occurrences are usually very rare, they can still occur under extreme conditions.
Sources: Science Direct and Tilly’s Nest
Bedbugs (Came lectularius)
Signs and illness development
- Excessive loss of feathers
- Lesions found on legs and breasts
- Anemia
- Cloacal irritation
- Highly irritable chickens
Note: A chicken may succumb due to severe blood loss
Diagnosis
Look for empty exoskeletons, dark specks, and reddish stains in the coop.
Treatment, prevention, and control
You can use heat treatment to treat the coop when the chickens are outside. Create a sustained heating structure that can reach the highs of 130F. In severe cases, a veterinary may also prescribe pesticides to spray in crevices, corners, and cracks.
Zoonotic potential
Even though they don’t live in humans, bedbugs are a nuisance that feeds on human blood. The fact that these chicken parasites quickly spread means that you can unknowingly carry them to your house or spread them between different kitchen coops. Bedbugs result in itchy bites.
Sources: The Poultry Site and Science Direct
Scaly Leg and Scaly Face (Cnemidocoptes mutans)
Signs and illness development
- Crusty and lumpy scales that are uneven and slightly raised
- Thickened skin
- Necrosis, deformity, or lameness as a result of heavy crusting
- Crustiness that starts at the poultry’s beak and has a honeycombed appearance
Diagnosis
Check if your chicken has scaly legs that have thickened and they have a lumpy/rough appearance. In some instances, you might notice a lump that appears to be white growth on the leg.
Check if there is a sign of white or grey crustiness near the corners of your chicken’s beak. The formation of white crusts on the bird’s skin is the surest form of diagnosing this parasitic infestation.
Treatment, prevention, and control
A veterinary officer can recommend Ivermectin if the condition is severe. Besides that, a vet can recommend the use of Moxidectin for oral intake. You can suffocate the parasites by soaking the chicken’s feet in water to suffocate them. A scaly face can be treated with a petroleum jelly product or paraffin oil to suffocate the parasites and to promote the growth of new scales.
Zoonotic potential
Scaly leg and scaly face parasites are considered to be zoonotic. In human beings, they can cause a mild condition of hyperemia and pruritus.
Sources: Science Direct and The Chicken Vet
Intestinal Parasites (Chicken Parasites Worms)
These chicken parasites reside internally in the chicken’s body.
Examples of intestinal parasites include:
Capillaria
Signs and illness development
Signs of Capillaria are difficult to detect since this is a chronic type of infection. Some birds may, therefore, fail to show the obvious signs. However, you can analyze non-specific signs such as:
- Weight loss
- Intermittent diarrhea
- Reduced appetite
- Pale combs as a result of anaemia
Diagnosis
Faecal flotation should be done in order to identify if there are barrel-shaped eggs. But clinical tests are usually the most effective since they are more precise. So, a necropsy examination of the intestines and oesophagus should be administered.
Treatment, prevention, and control
Capillaria is a disease with multiple drug resistance and there treating it can be quite challenging. A veterinarian can however recommend the use of Ivermectin, Mebendazole, and Fenbendazole for therapy purposes.
To control the development and spread of Capillaria, it’s important to keep your chicken’s bedding dry. Don’t forget to change them frequently since these worms need a humid environment to lay eggs.
Zoonotic potential
While this is a worldwide zoonosis mostly of mostly small mammals, the chances of human disease are very rare.
Sources: WikiVet and Parasitipedia.net
Heterakis
Signs and illness development
The eggs of Heterakis worms can remain viable for several months in the right environment. This means that it may take time for symptoms to fully develop. Clinical symptoms of Heterakis include:
- Wasting
- Depression
- Diarrhoea
Diagnosis
If you have egg-laying eggs, you will notice a significant drop in the production of eggs. Proper diagnosis requires testing of the host faeces to check the presence of eggs.
Treatment, prevention, and control
Effective treatment involves the use of Mebendazole. It’s an oral medication that can be distributed to all your flock through food and water. Using hardware cloth for bedding also helps to minimize the chances of this parasitic infection.
To prevent and control the spread of Heterakis worms, your birds’ beddings should always remain dry. Additionally, make it a habit to change them frequently. Pasture rotation is also great, especially when the birds are still young.
Zoonotic potential
Birds that are infected with these worms can’t transfer them to humans. This is because Heterakis worms are not human parasites.
Sources Parasitipedia.net
Ascarids
Signs and illness development
Clinical signs and symptoms include:
- Drooping wings
- Anorexia
- Dehydration and diarrhea
- Stunted growth
- Changes in behaviour and dullness
- Weight loss and ruffled feathers
- Misshaped eggs and soft thin eggshells
- Lethargy
Diagnosis
Clinical diagnosis involves microscopic examination of faecal matter to identify the worms and eggs. Hens that lay eggs may produce misshaped eggs or eggs that have soft and thin shells. Your chicken may also appear dry, showcase the symptoms of lethargy with a noticeable weight loss.
Treatment, prevention, and control
Veterinaries usually prescribe Fenbendazole to treat Ascarids in chicken. You need to mix it with water and give it to your flock for a couple of days. Other treatment options may include the use of piperazine and levamisole.
To prevent the spread of this parasitic infection, quarantine the infected birds. Pasture rotation is also ideal for young birds.
Zoonotic potential
Ascarids can affect humans and when zoonotic ascarids do so, they rarely mature along the intestinal walls. Instead, the ascarids larva worms will migrate to the tissues. The signs and symptoms a person displays usually vary depending on the organs and tissues affected.
Sources: Washing State University and The Poultry Site
Trichostrongylus
Signs and illness development
Signs of Trichostrongylus may not be easy to identify since this parasitic infection is of chronic nature. In some situations, your poultry may fail to show obvious signs of infections. However, you can check for non-specific signs such as:
- Reduced appetite
- Anaemia and pale combs
- Weight loss
- Intermittent diarrhoea
Diagnosis
The veterinary can diagnose Trichostrongylus parasites by examining the faecal matter.
Treatment, prevention, and control
Trichostrongylus has the same morphology as hookworms. Vets recommend the use of a poultry wormer medication. A drug such as Kilverm is effective for treatment in birds with active infestations. Besides that, it’s ideal for prevention.
Other prevention techniques include proper feeding of the chicken. Don’t overcrowd the poultry in coops and ensure that the feeders are always clean.
Zoonotic potential
Human infections caused by Trichostrongylus are very rare. However, there have been a few incidences of infections in Australia and the Far East. Accidental infections usually result from eating products contaminated by the parasites.
Sources: Science Direct and The Chicken Chick
Tapeworm
Signs and illness development
- Worms in eggs, droppings, or throat
- Abnormal chicken droppings i.e. foam-looking droppings and or diarrhea
- Wattles and pale comb
- Dirty vent
- Weight loss
- Reduced egg production in hens
- Head shaking and stretching
- Sudden death
Diagnosis
To diagnose tapeworm, check if the chicken is displaying any change in behavior or physical appearance. Besides that, check for the presence of worms in the chickens’ throats or droppings. If you analyze the droppings, you will find that they are foamy or have blood.
Treatment, prevention, and control
Treatment of tapeworms in chickens involves the use of prescription medications such as Albendazole, Praziquantel, or Fenbendazole.
To control and prevent the spread of this parasitic infestation, always keep your poultry in a clean and dry coop. besides that, you should ensure that you properly feed your chicken and that food is always placed in clean feeders. Do not throw treats or feed on the ground as these edibles can easily get contaminated.
Zoonotic potential
It’s generally not possible to get chicken tapeworms from hens that have a slight infestation. But if the infestation is severe, then you may get infected by eating contaminated eggs.
Sources: Heritage Acres Market and The Chicken Chick
Gizzard worm
Signs and illness development
- Depression
- Weight loss
- Anaemia
- Stunted growth
Other clinical signs may include:
- Ulceration of the gizzard lining
- Partial sloughing of the gizzard lining
- Necrosis
- A ruptured or sacculated muscular wall
Diagnosis
You might notice that instead of your chicken putting on weight, it may start to lose it. If the diagnosis is not done earlier enough, then your chicken might waste away quickly. Besides that, your birds may stop growing, leading to stunted growth
Treatment, prevention, and control
Common treatment options involve the use of THC drugs such as Flubenvet. However, the veterinary can recommend treatment options such as Panacur and Leamisole among others.
Prevention of gizzard worms should involve worming your birds as recommended by the veterinary. It’s important that you keep your birds in a clean environment and use clean feeders to give them food.
Zoonotic potential
The Zoonotic potential is quite low. However, you can get gizzard worms from chicken meat that has not been cooked properly.
Sources: Veterinary Practice
Baylisascariasis
Signs and illness development
- Tiredness or fatigue
- Nausea
- Loss of coordination
- Enlarged liver
- Loss of muscle control
- Poor or no attention to surroundings
- Blindness and coma
Diagnosis
Diagnosis of baylisascariasis in chicken may involve checking the physical traits. You might notice that your chicken moves around less and this mainly happens due to fatigue. It may also fail to coordinate its movements and may not pay attention to its surroundings. Severe cases may result in blindness and even death. The earlier you diagnose this parasitic infection and administer the right treatment, the better it is for your chicken’s health.
Treatment, prevention, and control
Treatment usually involves supportive care. In case you notice a bird has been infected, you should isolate it from the rest of the flock and keep it in a warm place. Limit the chicken’s level of stress and supply it with adequate food and water.
Prevention methods involve keeping the chicken’s coon clean and dry. Do not allow dogs to defecate in areas close to where your chickens roam freely. In severe cases, your veterinary may prescribe a medication such as albendazoles.
Zoonotic potential
It’s possible for humans to get Baylisascariasis through the consumption of undercooked or raw meat. Ingesting an infected chicken product with the larvae can subsequently lead to larva migrans syndrome.
Source: Sciendo
Toxoplasmosis
Signs and illness development
Clinical signs usually include:
- Shrunken comb
- Weight loss
- Reduced egg production
- Trembling
- Poor coordination
Diagnosis
You might notice changes such as trembling and whitish diarrhoea. Your chicken will be physically weak with a significant drop in weight.
Treatment, prevention, and control
Treatment of toxoplasmosis usually involves supportive care. First, isolate the chicken and then put it in a warm and comfortable location. Thereafter, your veterinarian can administer the most appropriate drug including Diclazuril or pyrimethamine. To control and prevent the spread of toxoplasmosis, keep the coop clean and dry.
Zoonotic potential
While chickens are considered the most important hosts of Toxoplasmosis, the parasite is still transferrable to humans. You can get infected if you consumed raw or undercooked chicken meat that’s infected.
Sources: PubMed and PoultryDVM
Prosthogonimus (oviduct flukes)
Signs and illness development
- Lime discharge
- Soiling of feathers
- Reduced appetite
- Abnormal walking
- Difficulty in breathing
Diagnosis
You might notice that your chicken is producing lime discharge due to the presence of flukes in the cloaca. The bird may also lose its appetite and refuse to feed.
Treatment, prevention, and control
The veterinary officer can prescribe medications such as mebendazole and praziquantel to treat flukes. Preventive mechanisms that you can implement to control the spread of these parasites include chemical elimination of snails with molluscicides. If you are in an endemic region, ensure that the coop is dry and clean.
Zoonotic potential
Prosthogonimus is an infection that mainly affects birds and the parasite isn’t contagious for humans. So, you can’t get it through the consumption of infected meat or eggs.
Sources: Parasitipedia.net
Eye, Head, and Respiratory Parasites
These chicken parasites and diseases affect the eyes and heads of your poultry.
They include:
Oxyspiruriasis
Signs and illness development
- Eyelids that are stuck together
- Conjunctivitis
- Blindness
Diagnosis
You might notice that your chicken is frequently scratching its eye. Besides that, its eyelids might be stuck together or the chicken has turned blind.
Treatment, prevention, and control
For treatment, the veterinary may recommend levamisole for use as eye drops or oral administration. Besides that, Ivermectin eye drops are still effective.to control and prevent Oxyspiruriasis, keep the chicken’s beddings dry and frequently change them.
Zoonotic potential
You can’t get Oxyspiruriasis since this isn’t a human parasite.
Source: Parasitipedia.net
Trichomonosis
Signs and illness development
- Watery eyes
- Loss of condition
- Drooling
- Problem swallowing food
Diagnosis
This is a parasitic condition that normally develops rapidly and may first start with the development of smaller ad yellowish lesions around the oral mucosa.
Treatment, prevention, and control
Treatment usually involves treating or culling the carrier birds, a veterinary can prescribe a medication such as Antiprotozoal. To prevent further infections, it’s important that you clean the water sources and feeder regularly. Ensure that they are placed in a protected area to avoid contamination by other birds.
Zoonotic potential
A bird disease such as this rarely affects humans. So, it’s impossible for you to become infected by this parasite
Sources: Wikipedia and MS Manual
Crop Capillariasis
Signs and illness development
- Diarrhoea
- Generally poor health
- Death
Diagnosis
Poor vision in chicken and generally poor health. The infection can progress quickly and eventually result in death.
Treatment, prevention, and control
You can treat Crop Capillaria by giving your chicken prescription medications such as Ivermectin and Fenbendazole. To control its spread, ensure that the poultry is kept in a clean and dry environment.
Zoonotic potential
Generally, Capillariasis can’t infect humans.
Source: VCA
Gapeworm (Syngamiasis)
Signs and illness development
- Hissing or wheezing
- Coughing
- Gaping
- Panting
Diagnosis
Your chicken may be gasping for breath and coughing. Besides that, it may produce a wheezing sound.
Treatment, prevention, and control
A veterinary may recommend Aviverm or Flubenol for the treatment of these chicken parasites. To prevent its development, deworm your chicken twice annually.
Zoonotic potential
This parasite rarely affects human beings. In total, only 90 cases have ever been reported.
Source: Stanford University
Dispharynxosis
Signs and illness development
- Anaemia
- Emaciation
- Diarrhoea
Diagnosis
Your chicken may face emaciation, especially if they are still young. It may also be physically weak due to anemia and diarrhea.
Treatment, prevention, and control
Drugs for treatment should only be administered by the vets and this usually includes deworming medications.
Prevention and control of this parasitic condition involve proper sanitation. Food and water should be supplied in clean sources and the beddings should be changed frequently.
Zoonotic potential
Severe cases of Dispharynxosis may cause infections in humans
Source: Science Direct
Diarrhoea Parasites
These parasites cause chickens to diarrhoea and they include:
Coccidia
Signs and illness development
- Diarrhoea
- Loss of appetite
- Weight loss
- Pale combs
- Lethargy
- Loss of appetite
Diagnosis
If you have hens, you might notice that they are no longer laying eggs. They may also huddle due to the cold feeling and lose weight.
Treatment, prevention, and control
The most common treatment for coccidian is Amprolium. The medication blocks the parasite’s ability to multiply. You need to add Amprolium to the birds’ water supply. Alternatively, you can decide to give the chicken the medication orally.
To prevent and control the spread of such chicken parasites and diseases, provide adequate coop space, use clean feeders and supply the chicken with fresh water.
Zoonotic potential
Coccidia rarely affects human beings. However, humans can get infected by one of its species known as Cryptosporidium.
Source: VCA Hospitals
Blackhead (histomonas)
Signs and illness development
- Drooping wings
- Yellow droppings
- Unkempt feathers
Diagnosis
This parasitic disease normally spreads faster and your chicken may die within a couple of days. Diagnosis involves yellow chicken droppings due to liver infections. The chicken may also appear to be unkempt.
Treatment, prevention, and control
There isn’t an FDA-approved treatment for this condition. However, a veterinary may prescribe an arsenic-based medication. In case a chicken is infected, you can control the spread of the parasite by isolating it. Generally, ensure that the chicken coop is clean.
Zoonotic potential
Blackhead’s zoonotic potential to humans is since the parasite doesn’t infect humans.
Source: FDA
Hexamitosis
Signs and illness development
- Watery diarrhoea
- Unkempt feathers
- Rapid weight loss
- Listlessness
Diagnosis
Your chicken may stop eating due to loss of appetite and eventually lose a significant amount of weight. Its feathers may also turn dry and unkempt while diarrhoea may be yellowish.
Treatment, prevention, and control
There is still no recommended treatment or vaccine for this parasitic condition. However, the veterinary may recommend the use of oxytetracycline for two weeks. Management and prevention of hexamitiasis include increasing the ambient temperatures and generally keeping the coop and feeders clean.
Zoonotic potential
Hexamitosis rarely affects humans since parasitic infection is prevalent in birds. However, exercise caution when handling severely infected poultry.
Source: MSD Manual
Cryptosporidiosis
Signs and illness development
- Diarrhoea
- Sinuses
- Dehydration
- Gasping and coughing
Diagnosis
Your chicken may start to excrete watery diarrhoea and vomit. Besides that, it may have a high fever, vomit frequently, and lose weight.
Treatment, prevention, and control
Until now there isn’t a universally recommended treatment for Cryptosporidiosis. Management options usually include implementing good sanitation and biosecurity in order to minimize the chances of transmission.
Zoonotic potential
You can get Cryptosporidiosis by consuming raw or uncooked meat or contaminated eggs.
Source: Mayo Clinic