Gastroenteritis in Macaws: Vomiting, Diarrhea & Digestive Upset

Gastroenteritis is inflammation of the stomach and intestines. In macaws, pet parents may notice vomiting, regurgitation, loose or watery droppings, appetite changes, weight loss, or a bird that seems quieter than usual. Because birds hide illness well, even mild digestive signs can matter.

In parrots, digestive upset is not always a stand-alone disease. It is often a symptom pattern caused by something else, such as bacterial gastrointestinal infection, yeast overgrowth, parasites, toxins, foreign material, or a larger problem like avian bornavirus-related proventricular disease. Macaws are one of the species commonly affected by proventricular dilatation syndrome, which can cause vomiting, weight loss, and seeds in the droppings.

Another important detail is that true vomiting and regurgitation are not the same. Some macaws regurgitate as part of bonding or courtship behavior, but passive regurgitation, repeated vomiting, or vomiting paired with lethargy and abnormal droppings is more concerning. Your vet may need to sort out whether the problem is in the crop, stomach, intestines, liver, or elsewhere.

The good news is that many macaws improve when the cause is identified early. Supportive care helps stabilize the bird, but the best treatment plan depends on what is driving the digestive upset.

Macaw digestive upset has many possible causes. Infectious problems include bacterial gastrointestinal infections, yeast such as Candida, and some parasites or protozoal infections. These can lead to vomiting, watery droppings, lethargy, crop changes, and poor appetite. In some birds, stress, poor sanitation, spoiled produce, or contaminated food and water can make these problems more likely.

Diet and environment matter too. Sudden food changes, very rich treats, moldy food, foreign material, and unsanitary bowls can irritate the digestive tract. Toxins are another major concern in parrots. Heavy metals like lead and zinc, pesticides, caustic materials, and some medications can all cause vomiting and abnormal droppings. Macaws may also chew inappropriate objects, which raises the risk of obstruction or toxic exposure.

Your vet may also consider diseases that mimic gastroenteritis. In macaws, avian bornavirus-associated proventricular dilatation disease is an important rule-out when there is weight loss, vomiting, or undigested seeds in the stool. Crop infections, liver disease, and systemic infections can also look like a stomach problem at first.

Because the list is broad, there is no one-size-fits-all answer. A short episode after a diet mistake may need very different care than a bird with chronic weight loss and recurrent vomiting.

Diagnosis starts with a careful history and physical exam. Your vet will ask about the exact droppings changes, whether the bird is vomiting or regurgitating, recent diet changes, access to metal objects or toxins, weight trends, and exposure to other birds. An accurate body weight is especially important in birds because even small losses can be meaningful.

Initial testing often includes fecal evaluation and Gram stain to look for abnormal bacteria or yeast, along with bloodwork to assess hydration, infection, organ function, glucose, and electrolytes. Depending on the case, your vet may also recommend crop testing, parasite screening, or PCR testing for infectious diseases such as avian bornavirus or other psittacine infections.

Imaging is often helpful when vomiting, chronic weight loss, or undigested seeds are present. Radiographs can help look for metal ingestion, obstruction, organ enlargement, or changes in the proventriculus. In more complex cases, your vet may discuss contrast studies, ultrasound, endoscopy, or referral to an avian specialist.

Hospitalization is sometimes the safest next step, especially if a macaw is dehydrated, weak, or not eating. Birds that need warmed fluids, assisted feeding, injectable medications, or close monitoring usually do better with in-clinic support while test results are pending.

Prevention starts with daily basics. Offer fresh, species-appropriate food, remove produce before it spoils, and wash bowls and food-prep surfaces regularly. Clean water should be available at all times. Good sanitation lowers the risk of bacterial and yeast overgrowth, and safe food handling also helps reduce Salmonella exposure for both birds and people.

Avoid sudden diet changes whenever possible. If your vet recommends a new pellet or fresh-food plan, transition gradually. Keep your macaw away from peeling metal, costume jewelry, hardware, batteries, pesticides, toxic plants, and household chemicals. Parrots explore with their beaks, so environmental safety is a big part of digestive health.

Quarantine new birds and avoid direct contact with birds of unknown health status. Infectious disease risk is higher in newly acquired birds and in birds exposed to outside birds through stores, shows, or shared equipment. Routine wellness visits with your vet, including weight checks and discussion of droppings quality, can catch subtle problems earlier.

At home, learn what is normal for your macaw's appetite, body weight, and droppings. A kitchen gram scale, clean cage paper, and a simple daily observation routine can help you spot trouble before a mild stomach upset becomes a crisis.