802 EXPERIMENT STATION BECOED. 



Rather recently there has been a notable revival of interest in ash 

 constituents in relation to animal feeding, as is witnessed by the 

 numerous reports of experimental studies which have been published, 

 the majority of them by European investigators, of the relation of 

 lime and phosphorus in different forms to the growth and develop- 

 ment of the body and to various questions concerned with mineral 

 matter and theories of nutrition. The work with farm animals has 

 kept pace with similar studies of the importance of mineral constitu- 

 ents in human nutrition, in which the demands of the bod}^ in adult 

 life are considered, as well as the special problems which pertain to 

 the period of infancy and youth. 



The foreign work has aw^akened a good deal of popular interest and 

 as a result it has become a by no means uncommon practice to supply 

 calcium phosphate in the form of bone meal or in some other way to 

 farm animals fed for different purposes, as well as to young and 

 growing animals. 



A considerable number of mineral mixtures have been placed on 

 the market in Europe, and as is the case with many such commercial 

 products it has been shown by investigation that these mixtures are 

 made up of materials of rather low cost and that if a farmer desires 

 to use them he may make them at home for considerably less than the 

 usual market price. 



In the United States the work carried on at the New York State 

 Station, which contributed so much to our knowledge of the phos- 

 phorus-containing body called " phytin " in wheat bran and its ap- 

 pai'ent phj'siological importance, is a noteworth}' contribution to the 

 subject of mineral matter in relation to animal nutrition. This sta- 

 tion has also reported valuable work on the importance of mineral 

 matter in poultry feeding. 



Mention should also be made of the important studies of iron in 

 food and its functions in nutrition, and of other mineral constituents 

 of the diet carried on as a part of the cooperative nutrition investiga- 

 tions of the Office of Experiment Stations. 



The extended study of the composition of local-grown feeding 

 stuffs at the Hawaii Station showed that many of them, particularly 

 common forage crops, are deficient in lime, owing doubtless to the 

 fact that they are grown on volcanic soils. In man}" cases cattle have 

 not made good growth and milk yield has not been satisfactory. The 

 conclusion seemed obvious that this was attributable to the deficiency 

 in lime in some of the common Hawaiian feeding stuffs and as a 

 remedy it was suggested that the readily accessible feeds which were 

 richer in this constituent should be used in larger proportion or other 

 means taken to increase the lime content of the ration. 



Investigations undertaken under government auspices in the Trans- 

 vaal have shown a similar lack of calcium," or more accurately a defi- 



