Effects of dietary n-3 polyunsaturated fatty acids and ... - FINS

1 st WorkshopXIII International Feed Technology Symposiumof protein degradation. Presence of ammonia in silages which do not contain butyric acidis explained with the activity of plant enzymes [15]. All lucerne silages had ammonianitrogen in the amount above 100 g/kg N, which is considered as the highest level forquality silage [11]. That is the result of high solubility of lucerne proteins [13]. Wholeplant maize silage with urea added had the highest amount of ammonia nitrogen (> 320g/kg N), which was direct effect of the additive used. In that treatment total ammonia Ncame from two sources: from degraded proteins of the ensiled material and fromhydrolyzed urea CO(NH 2 ) 2 + H 2 O = CO 2 + 2(NH 3 ) . Aside from increasing crudeprotein content, additives based on urea have importance because they provide aerialstability of silages. In was confirmed [17] that alkaline mineral additives bind part of theorganic acids produced and stimulate fermentation and utilization of the remainingsugars, which decreases the possibility for later fermentation. This is very important inmaize plant silages, which are very susceptible to secondary fermentations due toresidual sugars. Ammonia also may have fungicide effect [6]. Addition of organozeolitesignificantly decreased amount of ammonia, which can be explained with the absorptivenature of zeolite [10].The use of inoculants produced significant increase in lactic acid production, which wasmost evident in maize silages. On the other side, the use of ammonia significantlydecreased activity of lactic acid bacteria. The variability in total acetic acid was notsignificant. Butyric acid was detected only in whole maize plant silage with added urea.Reduced fermentation in maize cob silages can be explained with the high dry mattercontent of the raw material, which is limiting microorganism activity.CONCLUSIONIn this experiment the highest significant importance was observed in the use ofcarbohydrate and biological additives for lucerne silages, because they had stimulatingeffects which were significant in all parameters of silage quality. The use of urea in theamount of 5 g/kg green mass increased significantly nitrogen content in maize plantsilages, without negative effects on fermentation. The use of organozeolite had nomarked effects on chemical composition and quality of silages, but it decreased degreeof proteolysis.Further investigations need to focus on interactions with simultaneous use of two ormore additives, in order to determine cumulative positive effects and optimal doses ofadditives in those combinations.ACKNOWLEDGEMENTSThe Ministry of science and technological development of the Republic of Serbiafinanced this investigation within the project TR-20106.REFERENCES1. Official Methods of Analysis of AOAC international. 17th ed. Association ofOfficial Analytical Chemists, Washington, DC, 2002.150