[Control of the fermentation activity during ensilage of Lolium italicum A. Br. and Medicago sativa L].

Samples with different dry matter contents of Lolium italicum A. Br., Medicago sativa L., have been ensiled in hermetically sealed containers, in order to study the evolution of microflora and its activity. The principal microbial groups (coliforms, proteolytics , lactic acid bacteria, clostridia, yeasts) have been detected and enumerated, in anaerobic atmosphere, after ensiling periods of 3, 6, 10, 13, 20, 100 days. At the same time, the samples were chemically analyzed for the detection of: pH, moisture, ashes, total and ammoniacal nitrogen, total reducing sugars, lactic acid, volatile fatty acids, short chain alcohols. The relations found between chemical and microbiological data, show that a strong lactic fermentation is not enough for the inhibition of silage spoiling microorganisms, such as coliforms, yeasts, and (less) proteolytics . This phenomenon may be related to the "quality" of the lactic acid microflora, more than to the characteristics of the environment.