342 DISEASES OF THE THYROID GLANDS 



and nervous disturbances present should make the clinical 

 picture complete and different from vascular goiter. 



Prognosis.— Complete recovery is possible in most cases. 

 In the milder forms it often disappears without any treat- 

 ment. 



Treatment.— An examination of the animal should be made 

 carefully and if any general disturbance is observed it should 

 be treated. Owing to the increased activity of the gland 

 locally, iodin preparations are contraindicated. Small doses 

 of tincture of opium (0.2 to 0.4 daily) can be tried. 



Should the glandular activity become too pronounced, as 

 indicated by hyperthyrea, ligation of a portion of the blood 

 supply to the gland would be indicated. However, in the 

 majority of cases this is not necessary as the symptoms will 

 subside in the course of a few weeks. 



Malignant Goiter.— Definition. —An enlargement of one or 

 both thyroid glands due to a malignant neoplasm. The 

 malignant growth is either a sarcoma or carcinoma. The 

 growth tends to invade the adjacent tissues and lymph glands, 

 or even to the extent of involving secondarily the lymph 

 glands of the thoracic cavity, the lungs, and other organs 

 and tissues. The condition may become generalized. It is 

 found mostly in old animals. 



Symptoms.— The malignant growth may be confined to one 

 gland, but in many cases occurs in both. When the enlarge- 

 ment once begins, its development is quite rapid, and is 

 characterized by an uneven, irregular form of the gland, the 

 presence of acute inflammatory symptoms, very sensitive, 

 and in some cases areas of degeneration and abscess forma- 

 tion are found. Within a short time general symptoms 

 are prominent. Emaciation and general cachexia develop 

 rapidly. The rapidity of its development and the fact that 

 it is usually an old animal affected would assist in making the 

 diagnosis. 



Diagnosis.— This is made by careful examination. The 

 characteristic enlargement and condition of the gland with 

 secondary involvement of adjacent lymph glands, together 

 with the general symptoms of emaciation and cachexia, and 



