Causes and Symptoms
Avian goiter or thyroid hyperplasia is most commonly caused by an iodine poor diet. The afflicted bird’s thyroid gland cannot produce enough thyroxine, and the brain responds by signaling the gland to increase the number of thyroxine-synthesizing cells. These additional cells cause the thyroid gland (located in the throat) to enlarge, which is the main symptom of the condition. The resulting goiter may be accompanied by vomiting, lethargy and difficulty in swallowing. Eventually, pressure upon the circulatory system and other complications may lead to the bird’s death.
Seed vs. Pellet Based Diets
Seed-eating birds, especially budgerigars (parakeets), are particularly susceptible to thyroid hyperplasia. Seeds vary, among species and locality grown, in iodine content and hence a seed-based diet may be fine in some cases but iodine-deficient in others. The surest way to prevent an iodine deficiency is to wean your pet onto a pellet based diet, with seeds being used as a supplemental food. Lafeber, ZuPreem, Pretty Bird and our other pelleted foods have been formulated to meet the specific nutritional requirements of a variety of bird species, and provide complete, balanced diets.
If your bird will not accept pellets, you might consider adding a preventative medication, such as Gimborn Iodine Solution, to the diet. Budgerigars seem to have rather high iodine requirements, while other birds vary in this regard, so each case must be reviewed with your veterinarian on an individual basis.
Please write in if you are considering iodine supplementation, or have questions regarding pellet-based diets.
A comprehensive bibliography of papers dealing with wild and pet bird nutrition, including iodine requirements in budgerigars, is posted at: