Coccidiosis

Coccidiosis is a parasitic intestinal disease caused by tiny single-celled parasites called coccidia. It most often affects pigeons, poultry (chickens, turkeys) and finches and canaries, especially young birds. Typical signs are diarrhoea, sometimes with blood, and weight loss. The disease responds well to treatment and is even better prevented with good hygiene.

In poultry and pigeons the disease is caused by coccidia of the genus Eimeria, and in songbirds such as finches and canaries mainly by the genus Isospora. Most species are adapted to a particular bird species, so chicken coccidia do not usually pass to pigeons and vice versa.

An infected bird sheds microscopic oocysts – tiny, hardy parasite capsules – in its droppings. In a warm, damp environment they mature quickly and become infectious. Another bird swallows them with food, water or bedding, and the parasites then multiply in the intestinal cells and damage them.

Many birds carry a few coccidia without any harm. Disease occurs when the number of parasites rises sharply:

• damp, dirty bedding, especially around drinkers;
• overcrowding in the cage, aviary, loft or henhouse;
• droppings getting into food and water;
• young birds that have not yet developed resistance;
• stress, moving, shows, races and other diseases.

Oocysts can survive in the environment for months and are resistant to many common disinfectants.

Digestive signs:

• diarrhoea, often watery or slimy;
• bloody droppings or droppings with traces of blood, most pronounced in poultry;
• discoloured, foul-smelling droppings, greenish or brownish;
• soiled feathers around the vent.

General signs:

• loss of appetite and weight loss;
• ruffled feathers, drowsiness, the bird stands hunched;
• dehydration and weakness;
• in hens, a pale comb and a drop in laying;
• in pigeons, poorer form and worse racing results;
• stunted growth in young birds.

In young birds and chicks the disease can progress very quickly and cause deaths within a few days. In adults it is more often mild and long-lasting.

• there is blood in the droppings, or the droppings are entirely bloody;
• the diarrhoea lasts more than a day and the bird is getting weaker;
• the bird is not eating or drinking and stands ruffled up with its eyes closed;
• several birds in the flock have diarrhoea at the same time;
• one or more birds have died, especially young ones.

If you keep a flock, don't wait: coccidiosis spreads very quickly in damp, overcrowded conditions.

The diagnosis is made by examining the droppings under a microscope, where the oocysts can be seen. The vet also assesses their number, because finding a few oocysts in a healthy bird is not the same as disease. If birds are dying, a post-mortem of a dead bird quickly gives a reliable answer. Bring a fresh droppings sample, ideally collected the same day.

The vet prescribes anticoccidial drugs, for example toltrazuril or amprolium, and sometimes sulphonamides. In a flock the medicine is usually given to all birds, not just those showing signs. Weakened birds also need supportive care: fluid and electrolyte replacement and vitamins, as instructed by the vet.

Treatment will not help long-term unless the environment is sorted out, because birds keep reinfecting themselves from dirty bedding. Do not buy medicines without a prescription or give them on your own, as incorrect use can harm the birds and lead to parasite resistance.

• Separate the sick bird from the others and put it somewhere warm and quiet.
• Line the floor of the cage or box with paper and change it every day, so the bird does not reinfect itself from its own droppings.
• Give it access to fresh water, but do not pour it into its beak or force-feed it.
• Wear gloves when cleaning and wash your hands thoroughly afterwards.

If you have found a sick wild bird, hand it over to a rescue centre or a vet, as wild birds in Croatia may not be kept at home long-term.

• Dry bedding is the most important thing: clean damp spots immediately, especially around drinkers.
• Remove droppings regularly – in a loft or aviary, ideally every day.
• Wash drinkers and feeders every day and position them so droppings cannot fall into them.
• Avoid overcrowding and ventilate the space well.
• Hot water, steam and thorough drying are useful for cleaning, because oocysts cannot tolerate dryness and high temperatures.
• Quarantine new birds and have their droppings checked.
• Coccidiosis vaccines are available for poultry – ask your vet for advice.

Bird coccidia are not known to be a danger to people, but hand hygiene after handling birds is always necessary.

Coccidiosis is a common parasitic intestinal disease of pigeons, poultry and finches, and it is most dangerous for young birds. Bloody droppings and diarrhoea with weight loss are a reason to have the droppings checked by a vet promptly. Dry bedding, clean drinkers and regular removal of droppings are the best protection.