Reduced performance

SALMONELLA

This disease is zoonotic – this means it can cause disease in people.

Should you experience any vomiting, diarrhoea or abdominal pain please contact your local GP.

Symptoms

There are many different types of salmonella, with the most common in pigeons being Salmonella Typhimurium.

Healthy birds can carry this bacterium and shed it intermittently in their droppings.

Affects all ages of bird.

• Decreased appetite.
• Green diarrhoea.
• Increased loft mortality.
• Weight loss.
• Reduced reproductive performance/increased ‘dead in shells’.
• Swollen joints, lameness, drooped wings and difficulty flying.
• Loss of balance, circling and reluctance to move.
• Increased number of dead in shells.

Diagnostics

Three to five days pooled faecal sample for salmonella culture.
As the bacteria is shed intermittently by the birds then samples are sometimes required to be submitted on multiple weeks.
Cull or dead bird submitted for post-mortem.

Treatment

Treat according to culture and sensitivity.

Prevention

Regular cleaning and disinfection of the whole loft.
Avoid stress in the birds (overcrowding, other disease).
Vaccination is also available, but is unlicensed in pigeons.

INTESTINAL WORMS

There are a couple of species of intestinal worm that can cause a problem in pigeons:

Capillaria lives in all areas of a bird’s intestinal tract including crop, small intestine and caeca.
Ascaridia (roundworm) lives within the small intestines.

Symptoms

• Poor performance.
• Weight loss.
• Vomiting and internal haemorrhage with sudden death can be seen with Capillaria.

Diagnostics

Faecal egg count.

Treatment

Treatment is with levamisole products for three days.

Prevention

Worm eggs are very difficult to destroy with normal disinfectants. Routine cleaning and disinfection will be required to keep worm egg numbers low within your loft.

CANKER/ TRICHOMONAS

A protozoal pathogen that can be found in the mouth, throat and crop of around 80% of pigeons.

It is normally subclinical but can flare up and cause disease should the birds be young/ immunocompromised or undergo a period of stress.

Symptoms

• Some strains can cause high mortality.
• Poor performance.
• Hunched, depressed and weak birds.
• Sometimes struggling to breath.
• Sometimes diarrhoea.
• White/yellow plaques may be seen in the mouth.

Diagnostics

Fresh wet crop swab and investigation under microscope to look for motile protozoa.

Post-mortem: thickened crop wall, yellow plaques in oral cavity. In young birds may see umbilicus and liver lesions.

Treatment

Ronidazole and similar products given via the drinking water over a period of five or more days.

Some antibiotics have shown effectiveness against trichomonas, however, this pathogen shows increased levels of resistance and as such may not be effective for long. Check the flock for its presence two weeks after treatment.

Supportive treatment through vitamin supplementation and stringent hygiene measures will be enough to control an outbreak (see prevention).

Prevention

Ensure daily water changes.

Clean and disinfect water containers regularly. Ensure water containers, if not disinfected, can dry for 48 hours in order to dry out and kill resident trichomonas.

Water acidification helps to control gut flora and helps to manage motile protozoa, such as trichomonas. The pH of the water should be 3.8-4.0 and can be given for three to seven days a week.

Maintaining a healthy loft with regular health checks would help to prevent disease outbreaks. These could be a stressor and cause an emergence of clinical trichomonas.

MYCOPLASMA

Mycoplasma is an intracellular bacterium which effects the respiratory system of pigeons.

It can cause poor performance in both racing and breeding birds. It is difficult to eradicate entirely and can become resistant to antibiotics easily.

Symptoms

• Sneezing/ face wiping on perches.
• Watery eyes/ conjunctivitis.
• Thickened eyelids.
• Swollen infra orbital sinuses/swelling around the eyes.
• Nasal discharge.

Diagnostics

Throat swab PCR.

Treatment

Treat with Doxycycline or Tiamulin for five days if clinical signs become apparent. Once mycoplasma is in a loft, it is very difficult to eradicate. Retreating each time symptoms reoccur is an option but will reduce bird performance over time with continued antibiotic use. The mycoplasma may become resistant to the antibiotic.

All treatments should be performed only after consultation with a vet.

Electrolytes and vitamins can help to reduce symptoms.

In severe cases euthanasia may be necessary.

Prevention

Remove mycoplasma positive birds from the flock.

Isolate new arrivals for at least two weeks and monitor closely for respiratory illness.

Reduce pressure from diseases such as coccidiosis, worms, trichomonas and PPMV by carrying out testing, vaccination and treatment.

Good biosecurity: not allowing access to the loft for people who have been in contact with pigeons within the last 24 hours & reducing contact with wild birds.

Regular cleaning and disinfection.

ASPERGILLOSIS

Mainly caused by the fungal agent Aspergillus fumigatus, which is ubiquitous in the environment.

Disease occurs when birds are exposed to high levels of spores or the immune system of the bird is compromised due to stress or infected with other diseases.

Symptoms

• Poor performance.
• Weight loss.
• Difficulty/laboured breathing.

Diagnosis

Post-mortem findings.
Culture of the aspergillus fungus from an affected body tissue.
Histology of the affected tissues (usually the air sacs and lungs).

Treatment

Recovery of infected birds is slow and often unsuccessful despite treatment so return to racing fitness is unlikely.
Antifungal treatment in pigeons will not be licensed but can be attempted on veterinary advice where deemed necessary.

Prevention and Control

Monitor and address any diseases that may cause immunosuppression or stress in pigeons.
Check the loft for good ventilation. As a rule, if there is an excessive amount of dust/cobwebs or condensation in the mornings within the lofts there will be insufficient air flow. However, beware creating a draft.
Clean and disinfect the loft regularly to reduce the levels of spores in the environment.

CHLAMYDIA

This disease is a zoonosis. It can cause fever, headaches, pneumonia, meningitis and sometimes even death in humans.

Take extra precautions when handling birds positive for chlamydia, such as wearing gloves, overalls and facemasks. If you have any concerns about your health please contact your GP.

Symptoms

• Affects all ages of birds but clinical disease is worst in young birds.
• Conjunctivitis: Wet eyes, swollen eyelids and sometimes third eyelid protrusion.
• Nasal discharge.
• Gaping/noisy breathing.
• Poor performance.
• Diarrhoea/green faeces.
• Excessive drinking.
• Reduced fertility.

Diagnostics

PCR on pooled sample of faeces.

Treatment

Five-day course of doxycycline. However course may need to be repeated if symptoms persist.
Routine testing is advised after treatment to identify if infection is still present.

Prevention

Healthy birds can carry and spread the disease. Contact between birds of unknown disease status and your own birds is a risk.
Ensure stress factors are kept to a minimum, the following must be looked at:

• A thorough cleaning and disinfection protocol to reduce disease pressure
• Stocking density: is your loft overcrowded?
• Environment: is your ventilation adequate? As a rule, you shouldn’t have cobwebs forming if you having a good throughput of air. Does the loft smell of ammonia? Is it overly dusty?
• Disease control: ensuring absence of other disease such as trichomonas and paramyxovirus will allow birds immune systems to fight off incoming chlamydia more easily.

CIRCOVIRUS

This virus targets the immune system of pigeons, the main one being the ‘bursa of fabricus’ organ. This organ recedes as birds age.

It is potentially why this virus is known to cause problems in young birds of four weeks to four months old. However, there are cases of this virus affecting older birds too.

Symptoms

• Immunosuppression: will see a multitude of other diseases, such as trichomonas, salmonella, PPMV, yeast and fungal infections, alongside circovirus.
• Diarrhoea/green faeces.
• Depressed/hunched birds.
• Decreased feed intake and weight loss.
• Crop feed retention.
• Poor racing performance.
• Vomiting, difficulty breathing and loss of coordination/other central nervous system signs are less common but can be seen.

Diagnostics

Tissue, cloacal swab or blood sample PCR is the best way to see if circovirus is present.
Often not much to see on post-mortem but this may also help to identify concurrent diseases that circovirus has allowed in.

Treatment

There is no treatment. Birds should recover in five to seven days if no secondary infections are present.
Supportive therapy: electrolytes in water and probiotics may help the birds recovery.
Look for and treat other diseases to reduce pressure on the birds.

Prevention

Due to circovirus maintaining itself in the DNA of otherwise healthy birds that have been exposed in the past, it is suspected that these birds have become carriers for the disease.
Healthy carrier birds spread the virus from parent to chick and then that squab spreads it around the rest of the young birds.
Acidifying water will help control yeast infections (candida).
Routine cleaning and disinfection will help reduce exposure to other diseases.
Regular testing for chlamydia, trichomonas and parasite burdens would be beneficial to maintain good flock health.

Herpesvirus

Symptoms

Affects all ages of pigeon. Although clinical diseases tends to occur when birds are one to six months.

Birds may carry this disease without any symptoms, excrete it intermittently then spread it to those not infected.

• Eye and nasal discharge.
• Yellow/white debris in mouth.
• Difficulty breathing.
• Green watery droppings.
• Decreased breeding performance.
• Mortality within two days of symptoms is possible in up to 15% of loft.

Diagnostics

A PCR test is available to test faeces for the virus.

Treatment

Supportive: give electrolytes in water.
Secondary disease, such as bacterial disease, canker or yeast, may cause problems. Look for and treat according to symptoms.

Prevention

Quarantine of incoming stock.
Remove sources of bird stress (other disease, predators, overcrowding).
Routine cleaning and disinfection of entire loft.

ADENOVIRUS

There are two strains of adenovirus that are of importance in pigeons.

Symptoms

Classical’/ Adenovirus type 1 strain:

• Birds under one year old.
• Outbreaks seen a few days after racing usually.
• Green droppings.
• Increased water intake.
• Failure of the crop to empty.
• Loss of body condition in birds that have secondary yeast complications.
• Recovery in five to six days if uncomplicated.

Adenovirus Type 2 strain:

• All ages of bird.
• Outbreaks usually seen after racing.
• Causes necrotising hepatitis.
• Birds are severely depressed and die within two days.
• Yellow diarrhoea.
• Loft mortality can be 30+% of birds.

Diagnostics

Will require a post-mortem examination.
PCR test on faeces is available.

Treatment

Supportive treatment: Electrolytes in water.
Test and treat for any other diseases that may hinder bird recovery (coccidia, canker etc.)
Cider apple vinegar in the water (15ml/L) will help to prevent yeast infections in the crop.

Prevention

Keep bird stress as low as possible:

Make sure birds are not overcrowded.

Performing regular testing to monitor flock health status.

Vaccination to prevent outbreak of other diseases (PPMV).