Aside from the high proteid in the cow's milk, the overfeeding of artificially fed babies leads to a further increased introduction of pro teid. The digestion of proteids is more difficult than is that of carbohy drates or fats. Thus, we have an expenditure of 10 calories to digest 100 Gin. human milk, and of about 20 calories for 100 Gm. cow's milk. These calories may he utilized by the body for heating purposes, but when the heat excretion is deficient, or when much heat is produced in the body, they may become a burden and require special work for their removal. The infant, carefully guarded against chilling, may easily be inconvenienced through an excessive production of heat, and a moderate overfeeding even with human milk is therefore not desirable. Over feeding with cow's milk produces digestive distu•bances, NVI t IIINV:tSVd peristalsis, increased formation of feces. and gas in the intestines. As a result, the infants cry and become restless, and this again leads to an increased production of heat. The excess of heat haves the body tuainly by evaporation of water through the skin and lungs, as lleubner and Rubner observed in their metabolism experiment on an artificially fed infant.
It is possible that an infant may he raised on whole milk. The greatest care must be exercised in carrying oul this method of feeding, and the demand of the infant for excessive amounts of food must be refused with firmness. The amount of milk to be given should be smaller than the corresponding amount in the breast-fed infant. The method is not advisable in delicate and premature infants. It is better to dilute the milk somewhat, at least its the first weeks, but even if these precau tions are taken, the infants frequently do not thrive as well as desired. For this reason, the great majority of pediatricians, particularly in Germany, do not adopt this method, aim to reduce the proteid content of the milk by suitable dilution.
During the first weeks the degree of dilution should he such that the amount of proteid reaches approximately that of human milk. This is accomplished by adding two parts diluent to one part milk. Many people used to dilute the milk still more and even now higher dilutions are ,sometimes recommended, hut it is not rational to employ higher dilutions, for not only arc the proteids reduced, but at the saute time numerous other substances are diminished which the infant needs. In particular, the caloric value of the food decreases to such an extent that the necessity for a considerable increase of the total volume can hardly be avoided, in spite of the addition of suitable constituents:. The stomach and the intestines are thus directly Inirdened, and the total metabolism is overcharged (increased work of the heart. vessels, and increased production of sweat, with its consequences). As to whether infants recovering from disorders of the nutrition should not receive higher dilutions for a short time is another question.
The time of transition to more concentrated milk mixtures is given differently by different writers. The French physicians, for instance,
give half-diluted milk after a fortnight, while in Germany this dilution is rarely given before the end of the second month. It will be best to be guided in a given case by the state of the infant's health and particu larly by its digestive power. :-:ometimes the necessity arises to give general advice. If an infant is healthy, we very cautiously try to give half-diluted milk in the third or fourth week. and increase to two parts of milk to one part. diluent in the eighth week, three parts milk to one part diluent in the fifth month, and whole milk in the eighth month. With regard to the nutrition after the eighth month to the end of the first year, see p. 39S. Sometimes it will be necessary to give the stated dilutions for a longer period of time or to return to a higher dilution. The transition should he gradual, so that at one to two day intervals one bottle of the more diluted solution should be replaced by one of greater concentration.
Cereal decoctions or water are mostly used as diluents. Steffen recommended thin meat broths, and Monti whey. Since these diluents are wholly or to the greatest extent composed of water, an undesired diminution of the carbohydrates and fat takes place with the desired reduction of the proteids, and thus the nutritive value is markedly impaired. This disadvantage cannot be corrected by a corresponding increase in the amount of food, and an addition of one or more food materials is required.
Fats and carbohydrates may be added. The use of both seems to he the most rational, since thus we approach most nearly the natural conditions, and as a matter of fact such mixtures arc widely employed.
Biedert's natural cream mixture and the cream conserve (Rainogen) should be mentioned. The former is prepared by mixing cream, water, and sugar in the following manner: The cream is figured at 10 per cent. fat, 3.6 per cent. proteid and 4.5 per cent. sugar. Mixture I is to be used in the first month, II in the second, III in the third to fourth, IV in the fourth to fifth, and V in the sixth to seventh. Since the fat content of cream, which is not obtained by the use of machinery, varies considerably and as it is difficult to ob tain suitable cream particularly in summer time Biedcrt caused the above mentioned cream conserve to be prepared. It is put on the market in tin cans containing 260 Gm. and contains about 7 per cent. proteid, 15 per cent. fat, and 35 per cent. sugar (about. 10 Gm. of this are milk-sugar and 25 Gin. cane sugar). The cream conserve is given diluted with water or milk as desired. Biedert recommends the following mixtures: The composition of all preparations of infants' should be thoroughly understood. Only in this way is it possible to use them rationally and at the same time to exercise some control. It would he desirable if physicians would reject all preparations Ivhich do not satisfy this demand.