226 CARNEGIE INSTITUTION OF WASHINGTON. 



half-hour after levulose was 0.84. Thereafter it fell steadily and with con- 

 siderable uniformity until it approximated the basal quotient in the fifth 

 half hour, and in subsequent observations, in contrast with results found with 

 normal individuals, it dropped below the basal quotient. 



Other food materials studied were orange juice, dextrose, levulose, and fat, 

 beefsteak and butter, and oatmeal alone and combined with butter. A con- 

 siderable number of experiments were made after mixed meals. A rise in 

 metabolism was found with all of the food materials. After oatmeal and 

 fat the heat production increased on the average 22 per cent. On the typical 

 "oatmeal days" the metabohsm rose from 14 per cent after the first meal to 

 26 per cent after the fifth meal. An analysis of all of the food experiments 

 showed no special relation between the level of the basal metabolism and the 

 degree of reaction of the body to food. There was no marked variation in 

 the reaction to food with the diabetics as compared with that of normals. 



(11) Undernutrition in steers: its relation to digestion, metabolism, and subsequent reali- 

 mentation. Francis G. Benedict and Ernest G. Ritzman. Carnegie Inst. Wash. 

 Pub. No. 324 (1923). 333 pp. 



At the Agricultural Experiment Station at Durham, New Hampshire, 

 11 adult steers were subjected for 4| months to a reduction in ration amount- 

 ing to approximately half of their maintenance requirements. Three other 

 steers served as controls. Subsequently certain steers received fattening 

 rations of hay and grain, while others were put upon pasture. A special 

 respiration chamber was used to measure the carbon-dioxide production of 

 the steers at different nutritive levels. Chemical analyses were made of the 

 hay and different grains, and with two of the steers the composition of the 

 feces and the nitrogen in the urine were determined. 



As a result of the curtailment of ration, the steers lost on the average 

 23 per cent of their body-weight. During the last few weeks of undernutri- 

 tion the weights of practically all the steers remained at essentially a constant 

 level. On refeeding, large changes in intestinal ballast, due to retained feed 

 residues, resulted in rapid increases in weight. With heavy hay and grain 

 rations or pasturage the steers were readily fattened for market. 



The measurement of the carbon-dioxide production of the steers while 

 standing, with minimum muscular activity, and 24 hours after the last feed, 

 gave a basis for the computation of the heat-production. Per square meter 

 of body-surface the 24-hour heat-production at the maintenance level was on 

 the average 2,150 calories. This was subsequently lowered by curtailed 

 rations to 1,475 calories. A rapid return to the original metabolic level 

 followed realimentation with even moderate amounts of feed. It was com- 

 puted that these steers underwent a 50 per cent reduction in rations for 140 

 days with a loss to the body of 1,300 grams of nitrogen and approximately 

 52 kg. of fat. The actual cost in metabolizable energy for each kilogram of 

 body- weight gained during the realimentation period was essentially the same 

 with the undernourished steers (except for the grass-fed steers) as with the 

 control steers. It is concluded that adult steers may be carried through 

 the winter on extraordinarily low rations and subjected to heavy losses in 

 weight without experiencing permanent damage; and that they will be able 

 to regain their original weight and can be fattened for market with subse- 

 quent offering of plenty of feed. 



