Symptoms. 



971 



sharply demarcated from the surrounding tissue and form firm, 

 not very painful, tumors which are closely united to the carti- 

 lage, less often freely movable upon it. The nodular swellings 

 are as a rule of from hempseed to lentil size but may, in excep- 

 tional cases and in the larger birds, become as large as pigeon 

 eggs. The development of such thickenings on several joints 

 causes very striking deformities. The toes are spread apart by 

 nodes in their joints, are bent toward the soles and thus 

 apparently shortened. 



The motility of the affected joints becomes limited more 

 and more and may develop into complete ankylosis. Sometimes 

 sof t e n i n g occurs 

 later in some joints, 

 the skin over the 

 softened places be- 

 coming thinner and 

 finally necrotic ; 

 through the result- 

 ing opening a soft, 

 crumbly, yellow- 

 gray substance, like 

 gypsum, is dis- 

 charged. The bor- 

 ders of the ulcers 

 which form in this 

 manner are irregu- 

 lar and bleed easily ; 

 their base is formed 

 by cartilage or by 

 exposed bone tissue, 

 or the probe may 

 even enter an 

 opened joint. These ulcers jnay form in succession and become 

 confluent. 



Smaller hard nodes are sometimes found m the tendons, 

 skin and subcutis, and may even surround the base of the quills. 



With the further progress of the disease more joints are 

 constantly involved, and the nutrition of the animals is inter- 

 fered with. The feather coat becomes rough, some feathers 

 fall out, the comb and wattles become pale, the animals are 

 finally hardly able to move from place to place, and perish of 

 exhaustion and emaciation. 



In dogs nodular thickenings were observed on the lower articula- 

 tions of the feet and on the lower ends of the ribs. 



In the supposed gout of a horse Voigt noted pamful swellings 

 on the bones of the extremities near the joints, and lameness. Various 

 parts of the extremities were affected alternately, giving rise to 

 paroxysms. The appetite was diminished and the urine contained 

 uric acid crystals. The disease terminated in recovery in the course 

 of a year. 



Fig. 171. Articular gout in a hen. (After Kionka.) 



