Anatomical Changes, Symptoms. 957 



bulging; in other cases the tendons are loosened from the bones 

 and the articular cartilages have lost in substance. 



On histological examination the spaces between the bony trabeculae and Haver- 

 sian canals are dilated and bulging, while the trabeculae show the structure of 

 bony tissues almost only in the middle, their marginal portions, which are bordering 

 on the narrow spaces, assuming the form of a homogeneous transparent tissue 

 or of a cellular, non-calcareous tissue which may be finely or coarsely granular 

 (Fig. 167). The finer trabeculae consist in places exclusively of this tissue. The 

 marrow spaces are filled with a highly vascular tissue which is at first embryonal 

 and fibrillary and later contains more fat. The transformation and absorption of 

 the bone substance proceeds from the surroundings of these vessels in which multi- 

 nuclear giant cells appear (so-called osteoclasts). 



According to O. Weber the specific gravity of osteomalacic bones is low, the 

 fat content increased, the amount of inorganic constituents much diminished; the 

 gelatinous substances are also diminished. — Keuscher found of mineral constituents 

 only 32y2% instead of 60 in a thigh bone; in the ribs 30% instead of 57i/^; in 

 the vertebrae and the pelvic bones 26% instead of .57. The quantity of these sub- 

 stances is therefore reduced to one-half, the soft tissue increasing in like proportion. 

 Landois found in the bones of a horse with osteomalacia 1.5.85% of fat; 12.59 of 

 ossein; 47% of water, and 22.57% of lime salts, a percentage that was quite sim- 

 ilar to that of healthy bones. Hebrant & Mosselmann found the mineral constit- 

 uents diminished on an average by 10%, the ossein by 8-9% ; the water was in- 

 creased by 3-4%, the fat by 8-9%. Ingle showed also a marked diminution of the 

 ash constituents of the bones. 



Finally there are found changes suggesting anemia and 

 cachexia, principally edematous infiltration. The muscles which 

 are attached to the affected bones show atrophy and fatty de- 

 generation; in the joints and tendon sheaths inflammatory 

 changes are frequent, as are also ulcers in the articular carti- 

 lages. 



Symptoms. The signs which are characteristic of the dis- 

 ease are preceded, frequently in cattle, less so in the other 

 animals, by digestive disturbances and by symptoms of licking 

 disease. Such disturbances are observed also later after the 

 changes in the bones have become manifest. At first the ani- 

 mals simply lick the manger, the iron fastenings and the walls, 

 later they gnaw them and swallow portions of them. They 

 lick and gnaw preferably objects which contain lime, such as 

 mortar, sand, bits of stone and brick, earthen vessels, etc., also 

 woodwork, the latter especially if it is rotten or covered with 

 soot. Later on a predilection for objects which have a dis- 

 gusting smell and taste becomes more and more marked ; those 

 portions of the stable which are soiled with feces and urine 

 are sought out and eagerly devoured, and all sorts of foreign 

 substances are swallowed. At first the patients behave in this 

 strange manner only between feeding and eat the fodder which 

 is put before them readily, but later the appetite becomes 

 gradually worse, the animals become capricious, eat reluctantly, 

 slowly, and steadily' smaller amounts. Still later they refuse 

 good fodder entirely and their taste is perverted to such a 

 degree that they may prefer urine or ichor to pure water. 

 Meanwhile emaciation becomes manifest, the hair loses its gloss 

 and becomes rough, the skin becomes harsh and dry, rumina- 



