CHAPTER II. 

 DISEASES OF THE THYROID GLANDS. 



Examination and General Consideration.— Diseases involving 

 these glands are of considerable importance in dogs in which 

 animals all forms of goiter are found. Other small animals 

 are very seldom affected. The two thyroid glands, one on 

 either side of the neck, are situated in the upper third of the 

 cervical region. They are normally small but easily palpable. 

 When diseased they usually grow larger and tend to descend 

 downward toward the thoracic inlet. The position of the 

 diseased glands will vary, therefore, with their size and the 

 breed of dog. 



An important thing to be considered in connection with 

 the thyroid glands is the presence of small glandules closely 

 related to them. These glandules are often found in close 

 contact with the thyroid glands occurring in the adjacent 

 tissue or they may be quite a distance removed from them. 

 They consist of small, nodular glands, composed of true 

 thyroid or lymphoid tissue, and are considered accessory 

 glands to the thyroids. Normally they are very small, 

 but usually become much enlarged when the thyroid glands 

 are involved. These small glandules seem to be closely 

 associated with the thyroid glands in function, and will 

 replace to a certain degree the secretions necessary, when the 

 true glands are diseased or destroyed. 



CONGESTION OF THE THYROID GLANDS. 



At or near the time of puberty the glands are often found 

 enlarged; during the estrual periods the same condition is 

 commonly observed. This temporary congestion will disap- 

 pear in a few days in the majority of cases and the glands 



