788 EXPERIMENT STATION RECORD. 



"There was an increase in milk flow in 5 cases when the animals were fed a nar- 

 row ration over that obtained with the wider ration, and in 2 other cases the yields 

 were essentially the same in both tests, although in those instances the narrow ration 

 was fed i weeks after the wide. Of the 8 herds which were fed the wide ration 

 followed by a narrower one all except one gave an increase in butter yield during 

 the second test. The fact that there was more often an increase in butter yield 

 (calculated from the butter fat) than in the milk yield, during the period when the 

 narrow rations were fed, would indicate au increase in the percentage of fat as 

 a result of using the narrow rations. In some instances this was noticeably the 

 case. . . . There are 6 cases where the total cost of producing 100 lbs. of milk is less 

 with the narrower ration, and G cases where the cost of 1 lb. of butter is less. . . . 



"Although a shrinkage in production would naturally follow from advancement 

 in period of lactation, the herds as a whole more than held their own when changed 

 to the narrower ration from 1 to 4 weeks after the first test. The results are in 

 accord with observation and experiment elsewhere in that so far as physiological 

 effects are concerned narrow (nitrogenous) rations give larger yields of both milk 

 and butter than do wide (carbonaceous) rations." 



Contribution to the rational feeding of cov/s, O. Hagemann 

 (Landw. Jahrb.,26 (1897), No. 4-5, pp. 555-636). — This is a continuation 

 of the investigations, the account of the first part of which was pub- 

 lished about 2 years ago (E. S. R., 7, p. 237). As previously stated, the 

 author holds that, in order to draw reliable deductions as to the rela- 

 tive value of feeding stuff's for cows, experiments on the digestibility 

 and the metabolism of the food should be made. 



The present investigations covered 12 periods, about a year and a 

 half, and most of the time included 2 cows, although 5 cows were used 

 in all. A variety of grain and concentrated feeding stuffs were studied 

 in combination with other materials. Very complete data were secured 

 as to the amount and composition of the food, urine, feces, and milk, 

 and the live weight; and from these data the digestibility of the food, 

 nitrogen and ash balances, etc., were adduced. The full data for the 

 experiments are tabulated, and the author gives considerable space to 

 a discussion of his method of work and of the results of the experi- 

 ments. He notes the scarcity of data on the labor of digestion in 

 cattle. This can only be determined by respiration experiments and 

 without this the carbon balance can not be calculated. He believes it 

 probable that rations containing large amounts of starchy material, as 

 corn, rye, barley, with small amounts of hay and straw, require a much 

 smaller amount of labor for digestion than rations containing hay and 

 straw together with oil cakes rich in albuminoids. 



During the corn period with cow No. 3 and one of the rye periods 

 with cow No. 2 there was a nitrogen loss, although both cows were pro- 

 ducing large quantities of milk, but in all other periods nitrogen was 

 stored in the body. In these periods also there was a small loss of ash 

 constituents. The milk production appeared to be, to a certain extent, 

 dependent upon the feeding. It did not depend alone upon large quan- 

 tities of albuminoids in the food, as is usually stated, but- also on other 

 constituents. 



