866 EXPERIMENT STATION RECORD. 



The recorded data furuisli iiiforuiation regarding the amounts of protein, 

 fat, and glycogen katabolized in the body. The results show that the greatest 

 draft on body glycogen occurred on the first day of fasting. After this a 

 marked decrease in carbohydrate metabolism was noted and on the second, 

 third, and subsequent days not far from 20 gm. of glycogen per day was lost 

 on an average. 



The average heat production in the fasting experiments was found to be 

 not far from 2,000 calories per day on the first 2 days of the fasting period. 

 When the experiments were continued longer the heat production diminished 

 and the author believes that 1,500 to 1,600 calories per day may be considered 

 as approximately the minimum heat pi'oduction of a man at rest witliout food. 

 During sleep the heat production of such a man falls to 56 calories per hour 

 or at the rate of about 1,350 calories per day. 



The recovery from fasting was rapid and the author is of the opinion that 

 there is a marke<l tendency on the part of the body to accumulate fat after 

 sliort periods of fasting. 



Other general and pliysiological questions are also discussed. 



Metabolism during inanition, F. G. Benedict {N. Y. Med. Jour, and Phila. 

 Med. Jour., S6 {1907}, No. 12, pp. 527-536). — A brief discussion of results re- 

 ported in full in the publication noted above. 



ANIMAL PRODUCTION. 



The available energy of red clover hay, II. P. Armsby and J. A. Fries [U. S. 

 Dept. Afir., Bur. Anim. Indus. Bui. 101, pp. 01, df/nis. '/). — In continuation of 

 work previously reported (E. S. R., 17, p. 579), resiiiration calorimeter exper- 

 iments were made with a steer to secure additional data regarding the avail- 

 able enei'gy of red clover hay. The general plan was to feed the animal .3 

 different amounts of hay, all of them less than the maintenance re(]uiremeut, 

 and to study metabolism on each ration at different temperatures. It was 

 found, however, that the possible range of tempei"atui-e in the respiration cal- 

 orimeter chamber was so limited that the results regarding the influence of 

 this character are not considered decisive. 



According to the authors' results, 46.2S per cent of the gross energy of the 

 clover hay was metabolizable on an average, while 40.96 per cent was lost 

 in the feces, 6.81 per cent in the urine, and 5.95 per cent in methan. Consid- 

 ering the energy of digested matter only 78..39 per cent was metabolizable, 11.54 

 per cent escaping in the urine and 10.07 per cent in methan. 



In the 3 experiments the total heat production at a temperature of 19° C. 

 was 10,911, 11,435, and 10,724 calories, and in the experiments at a temperature 

 of 13.5° C. it was 11,7.36, 11,318, and 10,874 calories. The authors point out 

 that while the differences in heat production at the 2 temperatures were not 

 great, marked differences were noted in the channel of excretion, a much less 

 proportion being removed as latent heat of water vapor and correspondingly 

 more by radiation and conduction at the lower temperature. The i-elative 

 humidity of the air did not appear to have been an important factor in the 

 marked decrease in the evaporation of water noted at the lower temperature. 



On the basis of available data, the authors compute the minimum energy 

 requirements of a steer weighing 500 kg. to be 9,354 calories in their earlier 

 series of experiments and 9,527 calories in the experiments now reported. 



