18 OSSEOUS CACHEXIA. 



In the final stages, the hones may he cut with a knife, and a time 

 arrives when bony tissue seems completely to have disappeared ; thus, as 

 shown in Fig. 8 herewith, it was possible to cut the entire head of a pig 

 into thin slices without the slightest difficulty. All parts of the head had 

 been affected by the softening change. 



From the chemical point of view, the diminution in mineral salts and 

 in phosphate of calcium has long been recognised, l)ut the degree of this 

 change varies according to the phase. In human beings the proportions 

 have been estimated as follows: Normal bone, 50 to 80 per cent, of 

 phosphate of calcium ; bone in persons suffering from osteomalacia, 5 

 to 20 per cent, of phosphate of calcium. The changes in the ossein 

 have not been carefully studied. We only know that histologically the 

 ossein becomes fibrillar, and that chemically it no longer retains its 

 normal composition. 



The diagnosis is difficult, particularly on the first occasion of seeing 

 the disease, and especially if this is of an enzootic character. The 

 practitioner may also have some hesitation in diagnosing isolated cases 

 in regions where the disease seldom occurs. 



Otherwise, diagnosis is usually easy, as soon as lameness or synovitis, 

 or arthritis of the lower regions of the limbs appears. Only in isolated 

 cases are the lesions likely to be mistaken for accidental injuries, and it 

 is also fairly easy to differentiate them from the localised lesions of 

 rheumatism. The latter disease seems more frequently to attack the 

 upper joints of the limbs, and is often accompanied by intense fever and 

 cardiac disturbance. 



Prognosis. In a general sense the disease is very grave, because it 

 appears as an enzootic, and, in dry years and those during which there 

 is a scarcity of forage, inflicts enormous losses on the breeders of certain 

 countries. When advice is sought towards the end of the second phase 

 of the disease the prognosis is therefore very grave. Under such cir- 

 cumstances it is often better to slaughter rather than to treat, provided 

 that the affected animals, like cows, pigs, or goats are still of some value. 



The prognosis is much more hopeful if treatment is attempted at an 

 early stage, when improved diet and the use of suitable drugs sometimes 

 lead to recovery. 



Treatment. We know that in the Middle Ages this disease was often 

 treated liy the administration of crushed bones, and even at the present 

 day ground bones are frequently recommended. Treatment must be 

 subordinated to proper feeding, no system of medication being of any 

 value whatever unless the food is suitable. 



Germain states that imported horses in Cochin-Cliina recover if 

 simply returned to their former diet, i.e. to cereals and forage obtained 

 from France or Algeria. Cantiget shows that such improvements in 



