588 



Journal of Agricultural Research 



Vol. XV, No. II 



(6) More amino nitrogen was formed in the alfalfa silage than in the alfalfa 

 and carbohydrate silage. This difference is clearly shown in figure i . 



(7) Carbohydrate supplements exert a protein-sparing effect. 



In the second series of experiments begun on June 25, 10 milk bottles 

 were filled with cured alfalfa and the same number with cured alfalfa plus 

 5 per cent of cane sugar. The alfalfa used was of the first cutting, having 

 been cut on June 8. The data are presented in Table III, second 

 series. 



In the second series it was observed that alfalfa alone did not produce 

 undesirable odors as rapidly as in the first series. The offensive odor was 

 in evidence, however, on September 4, 72 days after siloing. The alfalfa 

 with the supplement had a good odor until the series was discontinued, 

 November 20, a period of 148 days. % 



A study of the data in Table III, second series, reveals the same general 

 conclusion as observed in the preceding experiment. Curves showing the 



amino-nitrogen deter- 

 minations of this series 

 are shown in figure 2. 

 The third series of 

 experiments were con- 

 ducted \\dth the second 

 cutting of alfalfa with 

 and without cane sugar 

 as in the previous ex- 

 -Tio — 740 160 ii< periments. The results 



Fig. I.— Graphs showing protein-sparing effect of carbohydrate in ^^^ given m iaDie ill, 

 alfalfa-silage fermentation, first series. third SCricS. 



The quality of the silage as determined by odor was as follows : 



July 16. Alfalfa alone, odor slightly undesirable; alfalfa and cane sugar, odor good. 

 July 26. Alfalfa alone, odor luidesirable ; alfalfa and cane sugar, odor good. 

 August II. Alfalfa alone, odor undesirable; alfalfa and cane sugar, odor good. 

 September 5. Alfalfa alone, odor tandesirable ; alfalfa and cane sugar, odor good. 

 November 20. Alfalfa alone, odor very tmdesirable; alfalfa and cane sugar, odor good 



The results presented in Table III, third series, are very similar to 

 those of preceding experiments. In this series casein agar was used 

 for the determination of casein digesters. The data obtained from this 

 medium are in most respects very similar to those obtained from the 

 use of gelatin. The ammonia determinations indicate the sparing effect 

 of sugar upon the protein, as also do the amino-nitrogen determinations. 

 The ammonia and amino-nitrogen determinations are plotted as curves 

 in figure 3. They indicate the same general results as the curves plotted 

 from the previous data. 



It thus appears that physical and chemical differences between the 

 two types of alfalfa silage were established. The data further demon- 

 strate that the carbohydrate acts as a protein sparer. 



