20 MISC. PUBLICATION 3 6 9, U. S. DEPT. OF AGRICULTURE 



An extensive and systematic spectrographic examination of samples 

 of herbage in abnormal and normal areas has shown that the molyb- 

 denum content of affected herbage is much higher than what is be- 

 lieved to be normal. Soluble molybdenum fed to cows produced 

 symptoms similar to those observed in cows grazing affected pastures. 

 In connection with this it might be noted that Stanfield (538) found 

 7 p. p. m. of molybdenum in alfalfa and 89 p. p. m. in barley hay, 

 while 317 p. p. m. of molybdenum was found in Atriplex nuttalli S. 

 Wats, growing in Steele shale in Wyoming (48). 



Losses of cattle due to eating of oat hay have recently been observed 

 in Wyoming by Bradley, Beath, and Eppson (86). It is not known 

 what influence, if any, the soil may have upon the development of the 

 toxicant, but "the localization of the problem suggests that local 

 influence must be of basic significance." The difficulty is apparently 

 believed not to be related to the occurrence of selenium. 



Other nutritional disturbances confined to certain areas have been 

 observed in British Guiana by Bone (82) and in Morocco by Velu 

 (574)- An endemic disease of horses in the mountainous districts of 

 the island of Hondo off Japan has been observed recently (563) . The 

 appearance of the disease coincides with the growth of vegetation — 

 May to November — and the pasturing of the animals during this 

 period. A botanical examination of the pastures failed to establish 

 that selenium-loving plants were present. No definite conclusions 

 have been drawn as to the cause of the disease. 



A chronic copper poisoning in sheep grazing in the vicinity of a 

 nickel smelter has been investigated by Bisset (74)- Copper, which 

 was present in large amounts in the livers of older sheep, was believed 

 to have been ingested with the soil rather than as a constituent of the 

 grass. 



A few observations have been made on the effect of deficiencies of 

 other elements such as magnesium, manganese, and zinc on animals 

 (55, 376, 485, 507), but relationships to environment have not been 

 observed. Among the rather interesting although inconclusive studies 

 is one from Czechoslovakia (433) in which it is claimed that 60 gm. 

 of gold per metric ton was found in the horn of a roe grazing on a soil 

 containing 0.1 gm. of gold per ton. No gold was found in the horn 

 of an animal grazing on plants grown in a soil that contained no gold. 



Several investigators in Europe (145, 146, 152, 491, 513) purport to 

 have found inverse relationships between the magnesium content of 

 the soil and the occurrence of cancer, but their studies are not of 

 sufficient extent to be thoroughly reliable. 



Summary of Sections on Soil Characteristics in Relation to 

 Nutritional Diseases of Man and Animals 



The inability of some soils to supply in proper amounts and pro- 

 portions those elements essential to the well-being of man and animals 

 has been known for more than a century. Investigations of certain 

 nutritional diseases of animals during the last 25 years have em- 

 phasized the importance of soils, for, throughout the world, the 

 occurrence of bone diseases, nutritional anemias, or of the effect on 

 animals of excessive quantities of some inorganic elements has been 

 characterized by the interspersion of normal and abnormal areas. 



