Dec. i6. 1918 Bacteriological Studies on Alfalfa Silage 585 



The bacteriological analysis varied slightly in the different experi- 

 ments, but the technic employed is the same as reported in the previous 

 work. Except in some cases, casein agar was used for the determina- 

 tion of casein digesters, and all gelatin cultures were incubated for 10 

 instead of 5 days. The chemical analyses included moisture, acidity, 

 amino nitrogen, and ammonia determinations. The acidity readings 

 are expressed in number of cubic centimeters of NI20 sodium hydroxid 

 required to neutralize 100 gm. of silage. The amino nitrogen was 

 determined by Van Slyke's method, and recorded as milligrams per 100 

 gm. of silage. The ammonia was determined by direct colorimetric read- 

 ings of extracts of the ground forage and recorded as milligrams per 100 

 gm. of silage. All data are calculated upon a moisture-free basis. 

 Three series of experiments were conducted, the first beginning on June 

 8, 1917, the second on June 25, and the third on July 10. 



In the first series 15 milk bottles were filled with alfalfa and 15 with 

 alfalfa plus 5 per cent of cane sugar added as a supplement. The first 

 cutting of alfalfa was used in both cases. The results are given in 

 Table III, first series. 



The following notes pertaining to the aroma of the silage were recorded 

 as the bottles were opened for analyses : 



June 13. Alfalfa alone, odor good; alfalfa and cane sugar, odor good. 



June 15. Alfalfa alone, odor good; alfalfa and cane sugar, odor good. 



June 18. Alfalfa alone, odor not so good; alfalfa and cane sugar, odor good. 



Jtme 20. Alfalfa alone, odor not so good; alfalfa and cane sugar, odor good. 



June 22. Alfalfa alone, undesirable odor; alfalfa and cane sugar, odor good. 



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



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



The alfalfa silage at the conclusion of the experiment had the char- 

 acteristic offensive odor which had been observ^ed from the alfalfa silage 

 made in the wooden silos. The alfalfa to which 5 per cent of cane sugar 

 had been added produced a good quality of silage with a pleasant sour 

 aroma. 



The data submitted in Table III, first series, demonstrate that — 

 (i) There was little difference in the microbial flora of the two types 

 of sileage. 



(2) Both types exhibited a normal microbial curve of development — 

 namely, a rapid increase of numbers for the first week, followed by a 

 decrease. 



(3) The acidophylic organisms are the predominating group. 



(4) The gelatin liquefiers were inactive in the fermentation. 



(5) The acidity produced was characteristic of alfalfa silage. The 

 silage produced from alfalfa with a carbohydrate supplement contained 

 a higher acid content than the alfalfa alone. 



