PRINCIPLES OF VETERINARY SURGERY 605 



vaso-dilator nerves of the blood vessels in the bones, ending 

 in passive hypertemra, and consequently in energetic re- 

 absorption of the elements of the osseous tissue. Castra- 

 tion, by suppressing the seat of these reflexes, would again 

 contract these vessels and cure the disease. This theory is 

 opposed by certain facts. Cures have been observed after 

 Caesarian section and from medical treatment, and besides, 

 man is not immune. More recently Fehling declared his 

 opinion anew, saying that osseous cachexia is a tropho- 

 neurosis of the osseous system dependent on a disease of 

 the ovaries — a trophoneurosis, which on account of the im- 

 portant part played by the marrow in the composition of 

 the blood, usually leads to a general vitiation of the blood. 

 It must be also remembered that when Porro's operation is 

 performed the annexes seem sound, and that the micro- 

 coccus nitrificans is a saprophyte of the uterus. 



The direct or indirect role of the nervous system has 

 been postulated as a cause of the disease by Ogle, and 

 Virchow, in his classification of osseous cachexia, mentions 

 that there is a form of the disease dependent upon nervous 

 affections. Moses, on the other hand, has reported cases of 

 osseous cachexia in animals affected with syringomyelia. 



On the whole, all of these theories are absolutely insuf- 

 ficient to explain the appearance, development and lesions 

 of the disease. They do not supply demonstrative facts 

 confirming the theory of alimentary insufficiency which is 

 defended in the opening paragraphs of this chapter. 



SYMPTOMS. — Osseous cachexia always makes its ap- 

 pearance insidiously and without fever. The first symp- 

 toms pass unnoticed. During the first few weeks they are 

 too insignificant to be connected with osseous cachexia, ex- 

 cept where the disease is common or when it is enzootic. 

 The first manifestations are systemic disturbances. The 

 patients lose their spirits and display feebleness and lassi- 



