A lack of tyrosine can result in a deficiency of norepinephrine in certain sites of the brain, causing mood disorders, such as depression, stress and anxiety. Some food sources of tyrosine are soybeans, sunflower, almonds, peanuts, pumpkin and sesame seeds. An amino acid deficiency is frequently caused by protein malnutrition. Such deficiency states may be associated with improper diet, failure to digest and absorb properly, stress, infection or trauma, drug use, imbalances or deficiencies involving other nutrients and so forth. Psychotropic drugs are sometimes used experimentally when a bird is experiencing psychological or behavioral problems.
Sunflower seeds are available both raw and roasted, hulled and unhulled.
Salted sunflower seeds should NOT be used. Raw sunflower seeds are more nutritional and have lower fat content. Sprouted sunflower seeds may also be offered to your Greys and these supply them with the addition of vitamin C, little to no fat, and a highly digestible complex carbohydrate source. Now I bet you didn't realize there were so many good reasons for feeding sunflower seeds to your companion Grey. Seeds and nuts are highly nutritious foods and should be served in small amounts in a varied, low-fat, high carbohydrate avian diet.