
Review. “Minerals in Pasture and their Relation to Animal Nutrition”
Any fundamental research into the composition of pasture in relation to animal nutrition must necessarily be of great importance to New Zealand, which is pre-eminently a pastoral country. This is therefore a book which should be carefully studied by all who have the welfare of this country at heart—a country 94 per cent. of the exports of which is derived from pasture. This work is the outcome of the activity of the Empire Marketing Board in the mineral content of pastures investigation, and the book throughout bears the impress of authority at home and beyond the seas. An important part of any investigation is a search of the literature, but in this case by a resolution of an Imperial Cabinet sub-committee it was decided to collect and arrange in an easily accessible form all the information available and publish it at an early stage in the investigation. Dr. Orr and his assistant in this laborious work—Miss Scherbatoff—have carefully reviewed the whole field at their disposal. The introductory chapter deals with the economic importance of pastures, the lines of research, and the significance of chemical composition. The mineral contents of pasture are considered first from the historical view point and subsequently in the occurrence of

the commoner mineral elements calcium, phosphorus, sodium, potassium, and chlorine, and finally the rarer elements iodine, iron, manganese, magnesium, sulphur, silicon, fluorine, boron and copper. The compositions of good and poor pastures are considered side by side. A third chapter deals with the factors affecting the mineral content of pastures, a fourth describes conditions under which diseases due to deficiency of minerals in pasture occur, and subsequent chapters deal with deficiency diseases in Europe, Africa, Australasia, America and Asia. Horses occupy a chapter to themselves. The practical means of increasing the intake of mineral foods are discussed and a summary and conclusions conclude the book, which is well printed and affords the fullest references to those who wish to consult the original researches.
Dr. Orr is to be congratulated on this fresh instance of the virility of the Rowett Institute of which he is the director. It will be of the greatest value to students, especially those engaged in pasture work.
