148 



INANITION AND MALNUTRITION 



retarded ossification and deficient bony tissue, but no osteoid substance. The 

 proliferative zone of the cartilage was greatly increased in breadth. The 

 primary marrow spaces were filled with vascular fibrous tissue and few marrow 

 cells. Osteoclasts were present, but not abnormal in abundance. Korenchev- 

 sky and Carr ('23) likewise found young rats much more susceptible to rickets 

 when the mother was fed during pregnancy or lactation on diets deficient in 

 calcium or vitamin A. 



Stoeltzner and Salge ('01) confirmed Wegner's ('72) experiments resulting 

 in the production of osteoid tissue of puppies by adding phosphorus to the 

 calcium-poor diet, but they still designated this as "pseudorachitische Osteopo- 

 rose" rather than true rickets. 



Stoeltzner ('08), Lehnerdt ('09, '10) and Shipley, Park, McCollum, 

 Simmonds and Kinney ('22) found that strontium cannot successfully replace 

 calcium in preventing rachitoid lesions in puppies fed a calcium-poor diet. It 



Fig. 53. — From a photograph of a portion of a section of the upper extremity of the tibia 

 in a normal young albino rat about i month old, body weight 36 g. C, epiphyseal cartilage; 

 to the left of which is a vertical black band, representing calcified bone of the epiphysis. 

 To the left of this, a small part of the epiphyseal marrow (M) is visible. To the right of the 

 epiphyseal cartilage is a wide zone of enchondral ossification, with a network of ossified 

 trabeculae, finer next to the cartilage, and becoming progressively coarser toward the marrow 

 cavity (M') of the diaphysis. Prepared by von Kossa's silver method (calcified tissue black). 

 X50. (Preparation by O. J. Morehead.) 



appears that strontium, like calcium and phosphorus, may stimulate the forma- 

 tion of osteoid substance, which (in the absence or malassimilation of the salts 

 necessary for calcification) may persist in excessive amounts. The identity of 

 the lesions with those of human rickets is questionable, however. In genuine 

 rickets, the osteoid tissue appears incapable of calcification, even in the presence 

 of calcium salts, whereas in "pseudorickets" the osteoid tissue (if present) 

 becomes calcified as soon as the necessary salts are supplied. 



Lipschutz ('10, 'n, 'na) observed that puppies on a phosphorus-poor diet 

 develop bone lesions resembling those of scurvy, in connection with which they 

 will be discussed later. 



