ORGANS OF LOCOMOTION 139 



legs, which are bent or curved, the animal being "bow 

 legged." The bones are soft and so spongy that they 

 may be cut readily with a knife. The epiphyses of the 

 long bones are enlarged and irregularly club-shaped, 

 while the shaft is also irregularly thickened. There is 

 a subperiosteal, spongy layer. The yellow marrow is 

 red in color and is of a gelatinous consistency. There 

 may be ulceration of articular surfaces, and the flat 

 bones of the cranium and pelvis may be thickened and 

 rarefied. The nares and mouth may be practically 

 obliterated by the enlarged rarefied nasal bones and 

 hard palate; the teeth may appear deep-set on account 

 of the tumefaction of the alveolar tissue. In advanced 

 cases, lesions may be found elsewhere causing disturb- 

 ances of the digestive or respiratory system. 



Symptoms. The first evidence of the disease is 

 weakness, diminished or depraved appetite, and diarrhea. 

 But lameness or stiffness of gait succeeded by bending 

 or arching of the bones is the first positive indication of 

 rickets. At this stage the lying posture is almost con- 

 tinuously assumed. When the affected animals are 

 made to arise they complain of pain by grunting and 

 squealing, and not infrequently they will walk on the 

 carpal joints. There may be nervous disturbances 

 evidenced by dizziness, somnolence, and convulsions. 

 As the disease progresses the enlarged epiphyses become 

 evident and appear as a swollen condition of the articu- 

 lation. Similar bony enlargements may also occur 

 elsewhere. The bulging of the long bones of the front 

 legs exert undue pressure upon the ribs, which results 

 in disturbed respiration, and the vertebral column is 

 variously curved, upward, downward, or laterally. 



This disease is of a chronic nature and continues for 

 months unless death intervenes early, which is exceptional. 

 Diagnosis is not difficult after the changes in the bones 

 are evident, while the chronic nature of rickets is sufficient 

 to differentiate this condition from articular rheumatism. 

 Tuberculous osteitis is differentiated from rickets by the 



