200 THE PRACTICE OF VETERINARY MEDICINE. 



MOLLITIES OSSIUM. 



Definition. — An abnormal softening of bone, due to the 

 presence of a largely preponderating quantity of animal 

 matter, and a correspondingly small amount of earthy 

 material within the bone substance. 



It is very difficult to say what causes operate in the pro- 

 duction of this disease ; probably the food and water have 

 something to do with it. It also is very possible that a 

 predisposition to the disease may be transmitted by a sire 

 or dam to the progeny. Its presence is thought by some 

 veterinarians to depend upon or be connected with melan- 

 osis. 



* There was a grey horse brought to the infirmary a few 

 years ago that was suffering from this disease, and it was at 

 first thought that the trouble was due to carious teeth, but 

 afterwards the true condition was discovered. It was a 

 case of mollities ossium, the bones of the jaws were 

 very soft and cartilaginous, and in this case at least, I think, 

 it was due to a melanotic condition.' — (Smith). 



Symjptoms. — There may be observed difficult}'' in mastica- 

 tion, which gradually becomes better marked as the disease 

 progresses. The bones become more or less enlarged, and 

 take on a soft and cartilaginous character ; there may also 

 be a discharge, which is usually profuse and of a very offen- 

 sive character. 



Treatment — As no means are known by which a cure can 

 be effected, treatment should not be attempted except by way 

 of experiment. 



FRAGILITAS OSSIUM. 



Definition. — An unnaturally hard and fragile condition of 

 the bones, due to fatty degeneration of the animal matter, 

 leaving a superabundance of earthy material in the bone. 



