Trichothecene Mycotoxin Poisoning in Geese

Trichothecene mycotoxin poisoning is a toxic feed-related illness caused by molds that grow on grains and other feed ingredients. In poultry, trichothecenes are linked to feed refusal, poor growth, mouth and throat irritation or ulceration, stunted feather growth, and immune suppression. These toxins are most often associated with Fusarium molds, and one of the best-known trichothecenes in North America is deoxynivalenol, also called DON or vomitoxin.

Geese are not the species most often discussed in the veterinary literature, but they are still birds and can be affected when contaminated feed is eaten. Young birds are generally more vulnerable to adverse effects from trichothecenes. In a goose flock, the first sign may be that birds suddenly stop eating, lose condition, or seem painful around the mouth after a new bag of feed, damp stored grain, or spoiled ration is offered.

This condition is different from an infection. The problem is the toxin in the feed, not the mold itself invading the body. That means treatment usually starts with removing the suspected feed source and giving supportive care while your vet rules out other causes of weakness, diarrhea, oral lesions, or sudden drop in appetite.

The underlying cause is ingestion of feed contaminated with trichothecene toxins. These toxins are produced by certain molds, especially Fusarium species, that can grow on cereal grains in the field or during storage. Contamination is more likely when grain has been exposed to moisture, weather damage, poor drying, condensation, or long storage in humid conditions.

Common risk sources for geese include moldy commercial feed, home-mixed grain rations, damp cracked corn, spoiled wheat, feed left in wet troughs, and feed contaminated by dirty or wet bedding. Importantly, feed does not have to look heavily moldy to contain mycotoxins. Visible mold can be a warning sign, but toxins may still be present even when feed looks fairly normal.

Trichothecenes are a family of toxins, and DON is one of the most common in North American grains. FDA guidance for chickens allows up to 10 ppm DON in grains and grain by-products, with the added recommendation that those ingredients make up no more than 50% of the diet. Geese are not specifically listed in that guidance, so your vet may use poultry principles, the bird’s age, the ration history, and feed testing results to judge risk in your flock.

Diagnosis usually combines history, exam findings, and feed testing. Your vet will ask about recent feed changes, storage conditions, moisture exposure, how many birds are affected, and whether appetite improved after the feed was removed. In trichothecene toxicosis, hallmark clues include feed refusal, poor growth, oral irritation or ulceration, and possible immune suppression.

Because the signs are not unique, your vet may also look for other causes of weakness, diarrhea, mouth lesions, or flock illness. Depending on the case, this can include a physical exam, body weight check, fecal testing, bloodwork if practical, necropsy of a deceased bird, and evaluation for infectious poultry diseases or other toxins.

Confirmation is strongest when a diagnostic laboratory detects a trichothecene in the feed at a level associated with adverse effects. Feed analysis can be helpful, but it has limits. Not every toxin is tested on every panel, and contamination may be uneven within a bag or bin. That is why your vet may recommend collecting several representative feed samples and pairing lab results with the clinical picture.

Prevention starts with feed quality and storage. Buy feed from reliable suppliers, avoid torn or damp bags, and store grain in a cool, dry, well-ventilated area protected from rain, condensation, and rodents. Use older feed first, clean bins regularly, and do not leave feed sitting in wet troughs or on damp ground where mold growth is more likely.

Do not feed grain or pellets that smell musty, feel caked, look discolored, or show visible mold growth. Even then, remember that mycotoxins are not always visible, so good storage practices matter as much as visual inspection. If one bag or batch seems suspicious, remove it from all birds right away and keep a sample in a clean container in case your vet wants it tested.

For flocks with repeated feed issues, ask your vet and feed supplier about ingredient sourcing, turnover, and whether laboratory screening makes sense. Feed additives marketed as mycotoxin binders have uncertain benefit for trichothecenes such as DON, so they should not replace proper feed management. The most reliable prevention step is still to keep contaminated feed out of the ration.