The influence of wilting and compaction degree on parameters of chemical composition, proteolysis and quality of lucerne silage

Abstract

The influence of wilting, actually two levels of dry matter content (DM = 250 and 360 gkg-1) and three levels of compaction (460, 550 and 620 gdm-3) on variations in parameters of chemical composition, proteolysis and quality of lucerne silage was investigated. The experiment was set as 2x3 factorial with three replications per each treatment. Based on the results of chemical analysis, there was no significant variation within the contents of basic nutrients (p>0.05), while some variation was observed in lipid and carbohydrate contents. In silages with higher dry matter content the reduction of fermentation was observed, with acetate as dominant product in acid contents in A2B1 treatment, and also reduction in proteolytic processes which shows as lower ammonia and soluble nitrogen content (p lt 0.05). With the increase of level of compaction the increase in lactic acid was observed, with decrease in ammonia and soluble nitrogen (p lt 0.05). In material with natural moisture content, regardless of the level of compaction, the butyric fermentation was observed and intensified aminogenesis. On the basis of this investigation it can be concluded that wilting and adequate compaction are the key physical factors which influence silage quality parameters.

U radu je ispitivan uticaj provenjavanja, odnosno dva stepena sadržaja suve materije (SM = 250 i 360 gkg-1) i tri stepena sabijenosti (460, 550 i 620 gdm-3) na promene parametara hemijskog sastava, proteolize i kvaliteta silaže lucerke. Eksperiment je postavljen po statističkom modelu 2x3 u tri ponavljanja po svakom tretmanu. Na osnovu rezultata laboratorijskih analiza, utvrđeno je nesignifikantno variranje u sadržaju pojedinih hranljivih materija (p>0,05), izuzev masti i ugljenih hidrata. U silažama sa većim stepenom suve materije utvrđena je redukcija fermentacije, sa dominacijom sirćetne u ukupnom sadržaju kiselina u tretmanu A2B1, kao i redukcija proteolitičkih procesa, odnosno manji sadržaj amonijaka i rastvorljivog zota (p lt 0,05). Sa povećanjem stepena sabijenosti došlo je do porasta apsolutnog udela mlečne kiseline i smanjenja udela amonijačnog i rastvorljivog azota (p lt 0,05). U materijalu sa prirodnim sadržajem vlage, bez obzira na stepen sabijanja, došlo je do buterne fermentacije i intenziviranja aminogeneze. Na osnovu izvedenih ispitivanja može se zaključiti da su provenjavanje i adekvatno sabijanje ključni fizički faktori za parametre kvaliteta silaže lucerke.