You need to know that diarrhea in birds consists of three components: feces, urates, and urine. Waste is stored in the cloaca, which is a common discharge chamber for the digestive, urinary, and reproductive systems. Feces are produced in the digestive system and are usually green or brown in color. Urine and urates (the white, chalky part) are produced in the kidneys. Generally, birds produce a very small amount of liquid urine, and most waste from the kidneys is in the form of semi-solid white or beige urates. Sometimes, a larger volume of urine is produced (polyuria), which is often mistaken for diarrhea. Birds suffering from polyuria have a more liquid fecal output, but their fecal component remains solid and formed. Birds with diarrhea have a more liquid fecal component in their droppings. 
What are the causes of diarrhea in birds?
There are many reasons for diarrhea in birds. The cause could be simple, like a dietary change or excess fungal growth, or arise from complex disease processes. Many infectious diseases cause diarrhea, so it’s important to inform the veterinarian about any contact—direct or indirect— with other birds.
Bacterial infection Bacterial infections may originate from other birds, excessive growth of harmful bacteria in food or contaminated water containers, or spoiled food. Often, small amounts of potentially harmful bacteria exist in the digestive tract without causing any adverse effects. This bacterial population can proliferate if the bird’s immunity is reduced—such as during stress periods—and become pathogenic. Additionally, incorrect or excessive use of antibiotics can disrupt this balance and lead to disease. Viral infection Several viruses can cause diarrhea in birds. In most cases, diarrhea is one of several symptoms of illness and not the only clinical sign. Viruses can be transmitted through direct contact with an infected bird, shared food and water bowls, or through the hands or clothing of a person, depending on the type of virus. Fungal infection Candida is a type of microscopic fungus that normally exists in small amounts in the bird’s digestive tract. Stress or antibiotic use can lead to an overgrowth of this fungus and cause diarrhea. 
Parasites One of the common gastrointestinal parasites in pet birds is Giardia; a tiny organism that lives in the small intestine. Giardia can cause severe diarrhea and weight loss and has the ability to transmit to humans. Other small parasites like Hexamita and Coccidia are less common. Round and flatworms—specific to bird species—can occasionally cause diarrhea and do not transmit to humans. papilloma in the cloaca Papillomas are cluster-like structures resembling warts that mostly appear in the cloaca but may also develop anywhere in the digestive tract. These growths can sometimes cause diarrhea and have a higher probability of being associated with gastrointestinal cancer.
Obstruction Tumors or foreign bodies can obstruct the gastrointestinal tract. Sometimes, obstruction is associated with “intussusception”—a condition where a part of the intestine invaginates into another part, initially causing diarrhea and later leading to cessation of waste elimination. Use of antibiotics The use of antibiotics can disrupt the natural intestinal flora balance and lead to diarrhea.
Other causes of diarrhea in birds
- Cancer
- Poisoning (like heavy metals or toxic plants)
- Stress (like environmental changes)
- Metabolic disorders like liver or kidney disease, diabetes
- Dietary reasons like sudden food changes, consuming spoiled food, or food intolerance
- Malabsorption, such as liver disease, inflammation, or pancreatic infection
Your veterinarian will recommend specific diagnostic tests based on the severity of diarrhea, how long it has been present, and the presence of other symptoms. Birds showing other signs like vomiting, loss of appetite, or lethargy may require extensive diagnostic testing. If your bird occasionally has some droppings with liquid or loose fecal components and shows no other symptoms, it may be normal. However, if diarrhea persists (lasting more than a day), is frequent (continually recurs), or if other symptoms appear, it requires medical attention. Signs to watch for include
- Lethargy
- Fluffed feathers
- Hiding head under wing
- Decreased appetite
- Vomiting or regurgitating food
- Presence of blood in droppings, which appears as dark green-black tarry feces
- No fecal matter present in droppings
When does a change in bird fecal color occur?
The color of feces can also change due to dietary changes. For instance, if birds eat foods with high pigments like certain berries, tomato products, or colored pellets, the feces may take on the color of the food. However, if the feces are very dark green and black, the veterinarian should be notified immediately, as this color may indicate digested blood (melena). 
Diagnosis of diarrhea in birds
Your veterinarian will recommend specific diagnostic tests based on the severity of diarrhea or the presence of other symptoms. A thorough history is crucial for making a diagnosis. Be prepared to tell your veterinarian when the diarrhea started, what its consistency is like, and whether it contains blood. Also, describe the type of diet your bird is on, its chewing habits, and any potential contact with other birds. Diagnostic tests that your veterinarian may perform include the following:
- Complete physical examination
- Complete blood count (CBC) and blood biochemistry panel
- Cloacal and/or fecal sampling for bacterial culture and cytology analysis
- Radiography (X-ray) imaging to check for intestinal diseases
- Endoscopy to visualize the digestive tract or body cavity
More advanced tests may include:
- Cytological or bacterial culture from droppings or cloaca
- Fecal testing for parasites (sometimes over several consecutive days)
- Complete blood count (CBC)
- Blood biochemistry panel to assess liver, kidney, pancreas function
- Plasma protein electrophoresis to diagnose inflammatory or infectious disease
- Chlamydia test (psittacosis)
- Testing for heavy metals like lead or zinc
- Simple and contrast radiography (like barium)
- Fluoroscopy: live radiology to assess coordination of peristaltic movements
- Abdominal ultrasound to check for thickening of the intestinal wall, mass, or foreign body
- Endoscopy and biopsy or sample culture
- Exploratory surgery (laparotomy) to obtain samples from the intestine for definitive diagnosis
Symptomatic Treatment of Diarrheic Birds
While waiting for diagnostic results or disease progression, some supportive measures are taken:
- Hospitalization and round-the-clock care
- Fluid therapy (intravenous, intraosseous, or subcutaneous)
- Diet change to a light and digestible food
- Forced feeding through a tube for birds that are not eating
- Administration of antibiotics or antifungal medication to control microbial growth
If the cause of diarrhea is diagnosed, treatment may include a combination of the following:
- Hospitalization for fluids and injectable medications
- Antibiotics or antifungal medications
- Surgery or endoscopy to relieve intestinal obstruction
- Medications to protect the gastrointestinal tract or alter bowel movements
Care for a Diarrheic Bird at Home
If only one or two droppings appear to be diarrhea and the bird shows no other symptoms, return it to its normal diet—without fruits and vegetables—for 24 hours. Ensure that fresh water is plentiful and that the bird is drinking. Use plain paper (without any covering or bedding of any kind) at the bottom of the cage, and change the paper daily so you can monitor the droppings. If the droppings do not return to normal within 24 hours, if diarrhea worsens, or if other symptoms appear, contact your veterinarian. If your bird is being treated for diarrhea, make sure to administer all medications as directed, until the end of the treatment period, even if symptoms have resolved. Pay attention to changes in droppings and inform your veterinarian of any alterations. If no improvement occurs, if discharges worsen, or if the bird shows other symptoms, immediately notify your veterinarian.
Frequently Asked Questions
How can I tell if my bird has diarrhea or is just urinating more?
In diarrhea, the fecal part of the droppings (the green or brown part) loses its shape and becomes watery. However, if only the volume of urine has increased and the feces are still formed, the bird is suffering from polyuria, not diarrhea.
Can a change in diet cause temporary diarrhea?
Yes. An abrupt change in food, use of fresh foods or juicy fruits can cause temporary diarrhea. If diarrhea does not resolve within 24 to 48 hours or if other symptoms appear, a consultation with a veterinarian is recommended.
Can bird diarrhea be transmitted to humans?
Yes, in some cases. Some parasitic infections (like giardia) or bacterial infections (like salmonella) can be transmitted from birds to humans, especially if hygiene practices are not followed. Washing hands after contact with the bird or its droppings is very important.
