ENSILAGE 413 



Ensilage. The changes through which ensilage passes during its 

 curing was looked upon a few decades ago as being entirely microbic 

 in origin, but due to the work of Babcock and Russell (1906-10) 

 opinion swung in the opposite direction to such an extent that 

 microorganisms were generally considered as of little if any signifi- 

 cance in the normal fermentation of silage. Later (1912) Esten 

 and Moson considered the process entirely bacteriological. Three 

 chief fermentations were thought to take place: the lactic acid, 

 alcoholic, and acetic acid fermentation. The lactic acid fermenta- 

 tion was thought to be due to organisms similar to those concerned 

 in the souring of milk. It was also believed by these workers that 

 yeasts cause an alcoholic fermentation and that acetic acid bacteria 

 then oxidize the alcohol so formed to acetic acid. Samarani con- 

 cludes that the acetic acid fermentation in silage is due to the res- 

 piration of the plant cells, while the lactic acid fermentation is due 

 to bacterial action. The organisms responsible for the latter proc- 

 ess were identified by him as a bacillus and a coccus which occurred 

 in about equal proportions. The former he designated as the B. 

 acidi lactici of Hulppe, and the latter was considered identical with 

 the common streptococcus of milk. 



Counts made by Sherman on silage juice showed the presence of 

 from 1,500,000,000 to 4,800,000,000 per cubic centimeter, most of 

 which were slender rods, and he considered the organisms con- 

 cerned to be nearly related to the B. bulgaricus group of milk and the 

 B. acidophilus groups. 



However, the temperature, kind of silage, and other factors 

 would govern the bacterial flora, and Gorini distinguishes four types 

 of grass-silage prepared in pits, depending upon the predominating 

 type of bacteria as follows: (1) Butyric, (2) lactic, (3) putrefactive, 

 and (4) sterile or atypical. If the silage stage reaches a temperature 

 of 60 C. butyric organisms predominate; if 50 C. lactic organisms 

 prevail; putrefaction occurs at lower temperatures, and sterile or 

 atypical when the mass becomes superheated. Butyric silage is 

 objectionable because of the odor and taste which it is apt to impart 

 to the milk and the bacteria which enter from the surroundings 

 render the milk unsuitable for cheese-making. 



The acid-produqing bacteria of silage are found constantly on 

 corn fodder, so that silage made from corn is always amply seeded 

 with the organisms, but Gorini achieved considerable success by 

 inoculating fresh grass-silage with lactic acid bacteria, and Crolhois 

 found that the inoculating beet silage with lactic acid organisms 

 preserves it better, furnishes a more nutritive product, and sup- 

 presses the diseases to which the cattle fed on non-inoculated pulp 

 are subject. 



At least from a theoretical basis this would seem quite probable, 

 for it is known that beets contain in addition to many other products 



