Aflatoxicosis in Macaws: Mold Toxins, Liver Damage & Emergency Care

See your vet immediately if you suspect aflatoxicosis. Macaws can become very sick after eating food contaminated with aflatoxins, which are toxins made by certain molds, especially Aspergillus species. These toxins are most often linked to improperly stored grains, corn, peanuts, nuts, seeds, and formulated feeds. In birds, the liver is a major target, so illness can range from vague digestive upset to severe liver failure and bleeding problems.

Macaws may be at special risk because many pet birds are offered nuts, seed mixes, or treats that can become moldy if stored in warm or humid conditions. Aflatoxin exposure can happen as a single large exposure or as smaller repeated exposures over time. Chronic exposure may be harder to spot at first, because birds often hide illness until they are quite sick.

This condition is not something pet parents can confirm at home. If your macaw seems weak, stops eating, has abnormal droppings, or you find moldy food in the cage or storage bin, treat it as an emergency and contact your vet or an emergency avian hospital right away.

Aflatoxicosis is caused by eating food contaminated with toxins produced by molds, most commonly Aspergillus flavus and Aspergillus parasiticus. These molds grow best in warm, humid conditions and may contaminate crops before harvest or during storage. Merck notes that aflatoxins are a worldwide feed problem and are especially associated with grains and feed ingredients exposed to heat, drought stress, insect damage, or poor storage.

In pet macaws, likely sources include moldy peanuts, corn, seed blends, nuts, grains, table foods stored too long, and improperly sealed pellet bags or treat containers. Food does not always look obviously moldy. That is one reason aflatoxin exposure can be missed until a bird becomes sick.

The toxin dose matters, but so does time. A large exposure can cause acute illness, while repeated low-level exposure may lead to gradual liver injury, poor feather and body condition, reduced appetite, and a higher risk of bleeding or secondary illness. If you suspect a food source, save the packaging and a sample in a sealed bag for your vet rather than throwing it away immediately.

Diagnosis starts with a careful history and physical exam. Your vet will want to know exactly what your macaw has been eating, whether any food smelled musty or looked damp, how long signs have been present, and whether other birds in the home have been exposed. Because aflatoxicosis can look like other causes of liver disease or poisoning, diagnosis usually relies on combining history with test results rather than one single finding.

Bloodwork is often the first step. In birds, your vet may check liver-related values such as AST and bile acids, along with a complete blood count and clotting-related concerns if bleeding is suspected. Imaging such as radiographs or ultrasound may help assess liver enlargement, abdominal fluid, or other causes of illness. VCA notes that bile acids can help assess liver function in birds.

Definitive confirmation may involve testing the suspected food for aflatoxins and, in some cases, liver cytology, biopsy, or postmortem examination. Merck describes diagnosis as being based on clinical signs, liver lesions, and laboratory detection of aflatoxins in feed. Even if the diagnosis is not fully confirmed on day one, your vet may begin treatment immediately because delays can worsen liver damage.

Prevention centers on food quality and storage. Buy bird food from reputable sources with good turnover, check expiration dates, and avoid bags or containers that smell musty, feel damp, or show clumping, dust, or visible mold. Store pellets, nuts, and seed mixes in clean, dry, tightly sealed containers away from heat and humidity. Smaller packages are often safer for households with one bird because they are used up faster.

Be especially cautious with peanuts, corn, mixed seeds, and nuts kept in warm rooms, garages, or outdoor storage areas. Do not feed any food that looks stale or has been exposed to moisture. Wash food bowls daily and remove fresh foods before they spoil. If your macaw is on a varied diet, rotate stock so older items are used first and discarded if quality is questionable.

If a food recall involves aflatoxins or mold contamination, stop using the product right away and contact your vet even if your bird seems normal. FDA notes that pets may have liver damage before obvious signs appear. For macaws with any history of liver disease, your vet may recommend periodic weight checks and blood monitoring as part of a prevention plan.