DISEASES OF THE OKGAXS OF LOCOxMOTlON 191 



After the foot has healed it will l)e t'ouiul to he somewhat 

 larger than noi'innl. Tiie sole of the foot will be somewhat 

 tender for a while, and 1o prevent rehriiising and reforma- 

 tion of an ahseess it is well to i)laee a leather pad on the sole 

 of the foot. 



A condition due to cactus thorns has recently ])een studied. 

 This condition occurs in l)a])y chicks and is manifested by 

 the legs and feet becoming somewhat shrivelled or appearing 

 ''dried up." The toes nuiy become crooked and finally dry 

 gangrene and death of the young bird result. This condition 

 has been produced experimentally. 



GOUT OF FOWLS 



Gout of the joints is an inflannuation of the fibrous and 

 ligamentous parts of the joints. It is accompanied by an 

 excess of uric acid and deposits of urates of sodium in and 

 around the joints. 



Gout may also attack the internal organs and cause de- 

 posits of sodium urates in them. This type is called visceral 

 gout. 



Gout attacks man and some of the lower animals such as 

 fowls and dogs. 



The histology of urate deposits, both experimental and 

 gouty, have been studied by Krause, Rosenbach and Freud- 

 weiler. Their results all indicate that uric acid and urates 

 excite slight inflammatory reactions, cause a slight local ne- 

 crosis, and seem to act as a weak tissue poison. HowTver, 

 they may be deposited without causing necrosis. 



That urates mav cause necrosis in the tissues has been defi- 

 nitely established, and this may lead to connective tissue 

 formation and contraction. 



Gout is more common in birds force-fed and given rich 

 nitrogenous diet and in old birds where the eliminating ac- 

 tion of the kidneys is more or less impaired. Birds normally 

 excrete large quantities of uric acid, which appears on the 

 outer surface of the droppings as a whitish liquid or semi- 

 liquid. 



It would appear that the preponderance in the blood of 

 substances which are of acid reaction favors the precipitation 

 of uric acid. 



Uric acid is converted into sodium urate by the salts in the 

 blood in two ways : First, by breaking down of the nucleo- 

 albumins of the tissue and especially perhaps of those con- 

 tained within the leukocytes; and second, from similar sub- 

 stances contained in the food (Greene). 



Excess of uric salts in the blood may be produced either 



