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To meet the requirements for the other essential substances of the Vitamin B complex in Vitamin B1 (thiamine) assays, early workers used autoclaved yeast. Because of the uncertainties involved in obtaining a yeast quite free from the vitamin in question, the use of autoclaved whey and autoclaved liver has been advocated since the thiamine in these apparently is more readily destroyed. For these assays it is customary to place the test animals on the basal ration at weaning, hold them until the body stores of B1 are depleted, manifested by stationary weight, and subsequently for a given specified period add the material to be tested in amounts sufficient for considerably less than the optimum gain. Although theoretically it should be possible to use a test animal for successive assays, in practice it is customary to make only one assay with a given animal. Under these conditions, possible discrepancies in the basal ration may be masked, or the results may be modified by enrichments in the test material. Fu...

In animal studies pertaining to Vitamin E, varying amounts of fat have been used as essential constituents of the ration. Certain of these are known to have a specific influence on the rate of the ...

During an investigation pertaining to the mineral deficiencies of milk, it was observed that the young, born of milk fed rats in February and March, 1926, were smaller, and their rate of growth was far less rapid, than that of any which we had heretofore noted in a long series of milk fed animals. These young were furthermore much smaller than young born of these same mothers during October and September, 1925. The appearance of the young in all groups (6) were so strikingly similar, even though the milk modifications were somewhat unlike, that it seemed as if the difficulty must be inherent in the milk, and not in the added inorganic substances. This was further emphasized by the fact that in two cases in which the mother rats were being used as controls, the animals were receiving only milk with the customary iron and iodine additions.To determine what constituent of this particular “winter” milk was lacking, we reduced the number of young in each litter to four, and added to the milk rations of the mot...

During a recent study of the vitamin C needs of children which included determinations of the daily urinary excretions of ascorbic acid, one child developed a slight upper respiratory infection whi...

Rats fed on diets adequate in all other respects but low in the Vitamin A factor, develop, in the course of time, infection of the upper respiratory tract. The first symptoms of the dietary deficiency are snuffles, loss of appetite, and failure to gain. These animals invariably die unless appropriate dietary treatment is introduced fairly early in the course of the infection. Macroscopic examination of the various organs of these animals, with the exception of the aural and nasal passages, which have been found filled with pus, shows nothing consistently abnormal. Occasionally the lungs are infected, often the intestines are filled with gas and greatly distended. Death in these animals seems to be the result of an infection superimposed on tissues which have been altered by the dietary deficiency.The excessive reaction to infection of the upper respiratory tract (nasal and aural passages) of the artificially fed baby and the low incidents of such infection amongst breast fed babies, suggests that in the f...

Hartwell's1 method of determining the Vitamin B content of foods differs from that of other workers, in that it consists in measuring the effects of a given ration on the suckling young. Either just before or just following parturition the mother animal is put on a high protein ration containing all the known necessary constituents, with the exception of Vitamin B. In the absence of an adequate amount of Vitamin B the suckling young gain normally for about 13 days, when they suddenly develop convulsions, manifested by general muscular incoordination. This condition is frequently accompanied by unusual outcries, and dragging of the hind legs. The baby animal gasps for breath, and finally dies within a few hours. That these animals do not die of insufficient food is indicated by the fact that milk is very frequently found in the stomachs. When adequate amounts of Vitamin B are added to the ration the young animals develop normally and are weaned at the usual time.By this method,2 comparative studies of fres...

There is some evidence that superheating destroys the antirachitic effect of irradiation.1 In order to test this point further we have compared over a period of 10 weeks the growth performance of rats which were receiving a rachitic ration2 with that of animals receiving (1) similar rations which had been irradiated; and (2) the irradiated ration which had been subsequently superheated. This rachitic ration which consisted of a mixture of grains was finely ground, mixed with distilled water and heated until it was of a thick gelatinous consistency. Since even at 15 pounds pressure mixtures of this consistency seldom reach throughout temperatures above 97° C., it was thought that results with these rachitic rations might not be valid. Therefore, we have tested the effects of the addition to the ration of (1) boiled milk; (2) irradiated boiled milk; and (3) irradiated milk which was subsequently autoclaved.In order to test further the effect of superheating on the antirachitic properties of milk, we have us...

The investigation made for the purpose of determining the influence on the hemapoietic system of various substances commonly used in infant feeding included a study of both rats and infants.In the work with rats, substances recommended for infant feeding: carbohydrate milk modifiers, orange juice, tomato juice, autolyzed yeast, liver, egg yolk, Vitamin B containing extracts, and various iron and copper additions, were tested. These were fed in conjunction with milk in proportions comparable to those used in infant feeding. Unmodified milk diets including both boiled and pasteurized were included, also, for comparison. Fifty-seven animals were fed, 2 to 3 on each diet, for 6 to 18 weeks. Hemoglobin determinations (Newcomer method) were made at the beginning of experimental diet and after 7 weeks of the diet. Records of food ingestion and body weights were kept to see what relation these have to hemoglobin formation.The results of the investigation indicated that carbohydrate milk modifiers used in infant f...

Calcium, phosphorus and nitrogen retention studies comprising 46 metabolism periods with 8 children between 3 and 5 years of age lead to the conclusion that a pint of milk, furnishing 75% of the calcium, when included as part of a diet containing adequate amounts of phosphorus, protein, fat and vitamins from other sources will supply enough calcium to meet the needs of normal children of the ages considered. The conclusions are based on a comparison of the retentions of these essential growth constituents when the children were taking diets containing a pint and a quart of milk respectively. In one series of tests the children received cod liver oil; in a second, cod liver oil and Viosterol; and in a third during June and July they were given no cod liver oil, but spent a large part of the day out of doors. The average retentions following the various diet modifications are given in the table.Seemingly the difference in the amount of calcium retained by children receiving different levels of milk above a ...

It is well known that the fat-soluble dye, Sudan III., is readily deposited in the adipose tissue of animals. An attempt was made by the authors to study the movements of the dye under conditions where fat transport takes place (e. g., in starvation, phlorhizinand phosphorus poisoning). The dye readily migrates into the blood with the fat under these conditions, but is rarely found in the liver tissue into which large quantities of fat enter (fatty infiltration). This is explained by the observation that the Sudan III. is abundantly excreted with the bile into the intestine from which it may be reabsorbed. Sudan III., which is insoluble in water, is not excreted through the kidneys except where alimentary lipuria is induced (in rabbits and rats). The elimination from the liver is not accomplished through the solvent medium of fat excreted in the bile (lipocholia); but the dye is soluble in bile as well as in solution of the isolated bile salts. We have thus established a path of elimination for fat-solubl...

Calcium and phosphorus retentions in infants receiving 3 different types of cow's milk modifications have been determined. In 2 cases the infants, who were quite normal, received the particular modifications, namely boiled cow's milk, and dried milk† for several consecutive months during the first year, thus making possible a number of metabolism studies on the same infant. With the 3rd mixture, namely S. M. A.,†† the food was given from one to 2 weeks before the metabolic period, 2 studies being made with one infant; and one with a 2nd infant. The calcium and phosphorus retentions in one rachitic child have been included for comparison. Cod liver oil and orange juice were given daily in all but one case.

In order to obtain further evidence regarding the possibility of increasing the antirachitic potency of cod liver oil, we have fed groups of young rats (six each) a standard rachitic ration1 to which has been added 1 per cent of Norwegian cod liver oil. With one group the cod liver oil was exposed to the direct solar rays, according to the method outlined by Price.2 A second group received the same amount of cod liver oil, which had been irradiated with a Mercury vapor lamp, at a distance of two feet, for twenty minutes. Control animals were given the non-irradiated cod liver oil. To make sure that the oil, which was obtained from the same source in each case, would be evenly distributed in the ration, it was mixed with 2 per cent of corn oil, a substance which has been shown to contain no antirachitic properties. Two groups of animals receiving the basal rations have been included for comparison. In one case the ration was irradiated with the Mercury vapor lamp in the same manner as the cod liver oil.Our...

During an investigation pertaining to the influence of certain foods on anemia in rats, it was observed that the hearts of those having low hemoglobin values were considerably larger than the hearts of normal animals. Thereupon the weights of the hearts of the experimental animals, computed on the percentage basis, were compared with those of normal animals as given by Donaldson. Successive biweekly hemoglobin determinations were made throughout the period of study, the last being taken just before the animals were killed. The results indicate that there is a close correlation between the size of the heart and the degree of anemia. The heart weights of animals with high hemoglobin values—from 11 gm. to 14 gm. per 100 cc. of blood (Newcomer method) are comparable to those given by Donaldson. When the hemoglobin values fell to 10 gm. the hearts were slightly hypertrophied; this became more marked as the degree of anemia increased. At the very low hemoglobin levels, from 2 gm. to 3 gm. per 100 cc., the heart...

Vitamin B in the urine and feces of animals and in human urine has been demonstrated by Muckenfuss,1 Van Der Walle,2 and Cooper.3 According to Cowgill4 the vitamin in the urine represents the amount ingested in excess of the needs of the animal, whereas that in the fecal excretion has been shown to be unabsorbed material.5 The presence of Vitamin B in the urine of an animal, therefore, would seem to indicate the adequacy of the diet as a source of this factor; and the amount of the vitamin excreted in the feces should give some measure of the amount not available to the organism.With such an interpretation in mind, a study of the intake and excretion of Vitamin B (the antineuritic factor) has been made on a group of 11 artificially fed infants and the retention of the vitamin determined. Thirty-three collections of urine and feces were tested. The food of all the children consisted essentially of cow's milk, a carbohydrate modifier free from Vitamin B, orange juice, and cod liver oil. In a few cases a Vit...

In studies pertaining to the influence of the diet of the mother on the development of the suckling young of rats, it was shown that a high percentage of protein and inadequate amounts of Vitamin F fed during the lactation period result in certain untoward symptoms in the young.1 These symptoms were made manifest by extreme nervousness, muscular incoordination, sharp cries, and violent convulsions. In many cases, death followed.In order to determine the cause of these abnormal conditions in the suckling young, lactating rats were fed a series of diets in which the amount of protein as well as the kind of protein differed. The amount of the antineuritic vitamin at the different protein levels also was varied. In some cases the Vitamin F containing substance was autoclaved at a definite pH to rule out the possible influence of other substances contained therein. Other groups of animals received low protein diets to which were added certain amino acids: glycin and alanine known to have a stimulating effect o...

Cardiac hypertrophy resulting from nutritional anemia reported by Forman and Daniels1 was based on moist heart weights. There was nothing to indicate whether the enlargement was a true hypertrophy—an increase in muscle fiber, or was caused by an imbibition of water. In the present study both moist and dry heart weights of anemic rats at different hemoglobin levels, were compared on the basis of sex, age, body weight, and body length with those of normal animals of the same sex, age, length, and weight. In an attempt to determine the fate of these hypertrophied hearts, other anemic animals were fed anemia correcting diets. When the haemoglobin and red cell count were again within the normal range, their hearts were compared with those of normal individuals.The findings indicate that nutritional anemia produces a true cardiac hypertrophy, the result of increased muscle fiber. The dried heart weights were found to be distinctly heavier, whether compared on the basis of age, weight, or length, the degree of e...