263. Effect Of Food Upon Cow's Milk

It is hardly to be expected that the human and the bovine mother are subject to greatly unlike laws in the relation of food to milk secretion, and consequently the outcome of experiments with cows to determine the effect of feeding various substances on the composition of milk is of importance in this connection. It has been found, as stated, that sudden and pronounced changes in the food of the cow may have a temporary effect on the proportions of milk constituents, an effect only temporary, however. The bovine mammary glands have a constitutional gauge not easily changed, if changed at all. It also appears that heavy feeding with certain vegetable oils, like cottonseed, linseed, and sesame oils, may appreciably modify the relative proportion of individual fats in the milk fat, and that the physical condition of the butter fat is modified to a small degree because of a change in the relative proportion of the harder to the softer fats in the food. Various investigators, after feeding a vegetable oil heavily, have discovered its characteristic fats in the milk of the experimental animal, but only in very small proportions.

But granting all these facts, and also that the milk of the human mother would be similarly affected by the food constituents, especially the fats, there is nothing in this to indicate that the milk thus becomes harmful, because the changes brought about are simply a slightly different proportion of food compounds of known value. We are justified in concluding, then, that the foods which the nursing mother may eat include practically the whole list, provided the diet is kept up on a fairly uniform basis as to. kind and quality of material, involving no sudden changes, and that from it is excluded those foods which in particular cases cause discomfort.

264. Effect Of Medicines Taken By Mother

When we come to consider the effect on her milk of administering medicinal substances to the mother, the evidence at hand is more definite. It has been conclusively shown that iodin and salicylic acid, or their compounds, antipyrin, mercury, and other substances may pass into the milk, though in very minute quantities, but probably in sufficient amounts to affect the child. For this reason a nursing mother should take medicine only under the advice and direction of a physician.

265. Effect Of Psychic Condition

The psychic or "nervous" condition of the mother may have a profound influence upon the physical welfare of the nursing infant. There is abundant evidence that continued grief, melancholia, or great anxiety may seriously affect the child, causing a loss of weight and sometimes bowel disturbances. From such causes, as well as by severe chill or some other unusual physical experience, the secretion of milk may suddenly cease. There is evidence, too, that from these causes the milk may be so modified as to become harmful, though just what occurs is not known. It is a strange and unexplained fact. To suggest that some toxic body is developed through nerve reaction is simply to advance an hypothesis. It is important, therefore, that the mother avoid as far as possible all forms of disagreeable mental experience and maintain mentally and physically a condition of repose and comfort. If severe experiences are unavoidable, it may be wise or even necessary to transfer the child to artificial feeding or to a wet nurse.

266. Precautions In Feeding

There are certain precautions which should be observed in feeding infants, whether they receive mother's milk or are given artificial food. The feeding should be regular and, with a very young infant, once in two hours is probably good practice, although a single rule cannot be rigidly followed in all cases. It is a serious mistake for a mother to nurse her child too frequently as a means of quieting it whenever it is fretful. Such a practice may result in overloading the child's stomach. As the child grows older the frequency of feeding may be diminished.

The infant should be weighed frequently to determine its rate of gain. It should be said, however, that plumpness or the laying on of fat is not necessarily an indication of physical prosperity; indeed, a child may become too fat for its physical good. The real essential is the growth of the basal tissues, and the character of the food has much to do with this. Artificially fed children are often more fleshy than those fed at the breast, whereas the latter may in reality be making the more desirable growth.