Overfeeding, which IVO meet. with so frequently as a cause of dis eases of nutrition in breast-feeding, is easily possible in cow's milk feeding, as in all forms of artificial rearing. It is possible, since, as pointedly expressed by Epstein, "gate and market stand open." In spite of all our care as to quantity and caloric value, the efficiency of our precautions is so impaired hy the variations in the amounts of nutritive substances found in our market milk, that overfeeding is hard to avoid. The bad effect of overfeeding is increased by the fact, that with the use of less easily digested food an atonic condition of the stomach soon develops, which leads to a delayed emptying and consequent stagnation of the gastric contents (Pfaundler).
The milk of other animals, such as ass's, mare's, and goat's milk, is not of much practical importance in this country, since these animals are used but little in the farming and dairy industries, and their milk is rather costly. The reports from German clinics and French hos pitals of goat's and ass's milk give results which are very variable but on the whole rather unfavorable, and this method of feeding, even with direct application of the child to the nipple of the animal, offers no protection against diseases of nutrition (Marfan, Klemm, Schlossmann, Ranke, Czerny, Bruning).
In many countries the feeding with starchy foods in the early weeks of life is much practiced. These foods, whether in the form of cereal jellies, gruels, or various commercial infant foods, constitute a further cause of severe and even fatal diseases of nuttition, with acute or chronic course. Czerny-Keller, to whom we are indebted for the exact study and proper appreciation of the value of these disturbances, designate them by the striking name of "starch-injuries." I shall speak later about the symptomatology of these conditions, of which I still have a vivid remembrance front my service as assistant at Munich. These very disturbances demonstrate that methods of nutrition based upon theories or upon the results of metabolism experiments can suffer bad shipwreck in practical application. Although we have been furnished with metabolism experiments (Carstens, Heubner, et al.), which seem to demonstrate the value of certain starches in early life (to which however the different results of Schlossmann are opposed), nevertheless the method often fails us in practice.
Similar dangers are incurred much less frequently by the early use of other foods, particularly eggs and meat, which usually- produce severe disturbances mainly localized in the large intestines. Particu
larly the idiosyncrasy toward eggs in any form manifests itself in many children with the clearness of a scientific experiment. After the admin istration of the smallest quantity there can appear fever, foul diarrhcea, urticarial eruptions, and nervous disturbances. These symptoms, since they, show a great similarity- to the results of the injection of animal blood serum, are suggestive of poisoning by foreign albumin (Bendix, Finkelstein, et al.).
As to glutinous substances, Gregor has demonstrated their action in producing diarrhcea by- special nutrition experiments, while Czerny Keller report similar observations after feeding with a nutriment rich in glutens, as, for example, soup made of veal bones. They designate these disturbances "glaten-injuries." There is a critical period in an infant's life, during which the in fluence of the nutritive injuries sketched above is of special meaning and importance. Such a period is represented by the first weeks of life, during which most children react with severe symptoms against every' form of artificial nourishment. If this stage is survived, or if the dis turbances do not run an acute course, then deep-seated injuries of a chronic nature are often produced, which their results dominate the development of the child during the entire period of infancy and often long afterward.
I shall consider next the so-called mixed feeding rallaitement mixte"), which consists in the simultaneous administration of both natural and artificial food. This proceeding is in wide-spread use, for example, here in Bohemia, particularly among the Slavic population. With mixed feeding, diseases of nutrition appear less frequently ancl in milder form, than in the weaning period which constitutes a second critical time in the life of the infant. Observations of this kind, on the one hand are suggestive of the action of the enzymes of human milk, particularly its peculiar amylase, in strengthening digestion, and on the other hand they are suggestive of the injuring of the bowel by a foreign albumin.
In the most diverse countries and parts of the world there occurs a very marked increase in the infant martalOy in summer. This in crease, which is due to the frequent occurrence and severe course of diseases of nutrition, deserves a brief discussion here.