PRINCIPLES OF VETERINARY SURGERY 625 



to pressure with the finger. They become as soft as a pear. 

 The weakness and emaciation increases until the subject 

 remains permanently recumbent. 



4. Urinary Disorders. — Alterations in the composition 

 of the urine appear to keep pace with the osseous altera- 

 tions. Every case of general rarefying osteitis is accom- 

 panied with phosphaturia in proportion to its extent and 

 intensity. Normally, the elimination of phosphates varies 

 with the alimentation. From analyses made by Marcone on 

 healthy horses fed with various feeds, the quantity of phos- 

 phates (measured as phosphoric acid) eliminated, at no time 

 exceeded 9.60 grams daily, and sometimes it fell as low as 

 0.40 grams. On the contrary he found that horses sufifering 

 from osteoporosis eliminated as high as 14.440 grams, and 

 even 28.80. However, the diseased horse may not always 

 show an increased elimination of phosphoric acid, because 

 there may be momentary arrests of the process and hence ar- 

 rests of the elimination of phosphates. 



TERMINATION. — Death is the rule, but American 

 veterinarians have shown that a cure may be effected in 

 some cases. The evolution of the disease may, however, be 

 interrupted with frequent halts, as is proven by the momen- 

 tary disappearance of the lameness. And besides, autopsies 

 often reveal points in the osseous tissue where the dilated 

 Haversian canals and enlarged lacunae have been filled with 

 adipose tissue. The disappearance of the embryonic ele- 

 ments, and their replacement with adipose tissue, testifies 

 to the arrest of the process. 



The incurability of the disease is certain when the pro- 

 cess has reached its ultimate phase, — tumefaction of the 

 facial bones. All of the horses observed by Varnell died. 

 In spite of these assertions it has been shown that cures, — 

 perhaps exceptional, — have been effected in horses present- 

 ing deformities of the head. Marcone cites one instance of 



