336 DISEASES OF THE THYROID GLANDS 



formation occur. Should the function of the gland be 

 disturbed for a prolonged period either potassium iodid in 

 small doses or thyroid extract has proved to be of consider- 

 able value. When abscesses occur they should be opened, 

 drainage effected, and an iodin pack applied. 



GOITER. STRUMA. BRONCHOCELE. 



Definition.— A hypertrophy or enlargement of the thyroid 

 glands which occurs sporadically. It is very frequent in 

 dogs. In some instances goiter is congenital and whole 

 litters of puppies are affected. The enlargement of the 

 glands in these cases may be of sufficient size to interfere 

 seriously with parturition. Very often the glands will be 

 six to ten times larger than normal, seemingly as large as 

 the puppy itself. The lobes and isthmus of the glands are 

 so intermingled that no distinction can be made between 

 them, the whole forming one large mass in the inferior cervical 

 region. 



The disease is also acquired in a great many cases, coming 

 on at different periods in the development of individual 

 animals. 



Occurrence. — The occurrence of goiter in the various breeds 

 of dogs seems to be in about the same ratio, although in 

 certain districts pointers, bull dogs, and bull terriers, seem 

 to be affected in larger numbers than other breeds. 



Many forms of goiter are recognized in dogs, viz.: (a) 

 Parenchymatous; (&)' cystic; (c) fibrous; (d) vascular; (e) 

 malignant; (/) exophthalmic. 



Parenchymatous Goiter.— Definition.— A diffuse paren- 

 chymatous enlargement of the gland with an increase in the 

 stroma and a collection of gelatinous colloid material in the 

 follicles. 



Occurrence.— This form is by far the most common and 

 occurs more frequently in puppies or young dogs. 



Symptoms.— The first symptom noticed is the enlargement 

 of one or both thyroid glands. The enlargement may not 

 be equal in both glands. One is frequently much larger 

 than the other. This form of goiter often develops suddenly 



