972 Gout. 



Visceral gout is, in its ordinary course, manifested by sim- 

 ilar nutritive disturbances as the articular variety; but unless 

 the joints are likewise affected, the actual cause of the disturb- 

 ances cannot be recognized during life. 



Course and Prognosis. The course of gout is almost with- 

 out exception chronic, only Hartenstein observed the disease in 

 an acute form in geese. In most cases only one extremity is 

 affected at first, and other joints not for several months, usually 

 the corresponding joints on the other side ; in the meantime the 

 acute signs in the joint that was first affected have diminished, 

 and the general condition of the patient has improved. The 

 involvement of other joints is usually introduced by acute 

 sjmiptoms which, however, later go down. 



The prognosis is unfavorable, since complete healing is 

 rarely observed. This may be looked for at most in domestic 

 fowl that live in the open; in birds kept in captivity the disease 

 progresses steadily and leads the sooner to complete exhaustion. 



Diagnosis. For the positive determination of gout in the 

 living animal the microscopical or chemical demonstration of 

 uric acid or of urates is absolutely necessary. 



For the microscopical examination the material to be examined is rubbed 

 up on a glass slide with pure or slightly acidulated water, after which the crystals 

 of sodium urate are recognized as very fine needles which form sheaf-like groups 

 or radiating balls. The chemical test for uric acid is properly made with the 

 Murexid-reaction. The secretion is mixed in a porcelain dish with a few dro^is 

 of concentrated nitric acid and is warmed slowly until the mass is dried ; if ammoniac 

 is added to the onion red residue after this has become cold, it assumes a purple 

 color, while the addition of sodium hydrate produces a violet coloration which 

 disappears on heating. 



Tuberculosis of fowls or the chronic forms of fowl cholera 

 may cause similar changes in the joints, and if other indications 

 of these diseases are absent, or if no information is afforded 

 by outside conditions, the exact nature of the disease can be 

 determined only by the microscopical or chemical examination 

 of the secretion. Purulent arthritis and periarthritis, and also 

 articular rheumatism are differentiated, at least in a part of the 

 cases by a more chronic course. 



Treatment. The diet of the sick animals should be reg- 

 ulated in such a manner that they receive only limited rations 

 of nitrogenous substances, especially such as are rich in purin 

 bases or nucleoproteids. Alkaline salts (sodium bicarbonate, 

 Carlsbad salt, etc.) may be added to the drinking water. The 

 patients should be enabled to exercise freely, especially in 

 pure dry air, a desideratum which is usually not feasible in 

 captive birds. Experiments in birds having permitted the 

 conclusion that the deposit of urates is prevented when piper- 

 azine is present in the blood, this remedy might be tried in the 



