Kazalniki in vitro fermentacije in tvorba HMK iz nestrukturnih ogljikovih hidratov pri kuncih

Abstract

Six pure non-structural carbohydrates (glucose, fructose, sucrose, β-glucan, chicory inulin (inulin-C) and inulin of undefined source (inulin-N)) were incubated anaerobically in the inoculum prepared from rabbit caecum content and the kinetic parameters of in vitro gas production (total potential gas production (B), maximum fermentation rate (MFR), time when MFR was reached (TMFR), lag phase (Lag), the amount of gas (Gas8) and fermentation rate at 8 hours of incubation (FR8)) and volatile fatty acids (VFA) production after 8 hours were determined. MFRs were the greatest and TMFRs the shortest with the fermentation of sugars: glucose (MFR 36.0 ml/h; TMFR 8.6 h), fructose (MFR 38.6 ml/h; TMFR 9.6 h) and sucrose (MFR 33.2 ml/h; TMFR 9.4 h). Fermentation was the lowest in β-glucan (MFR 12.5 ml/h; TMFR 15.3 h), while fermentation of the two inulins was very different: fermentation of inulin-N was intensive and fast and similar to sugars (MFR 32.3 ml/h; TMFR 8.3 h), while inulin-C fermented slowly and with low intensity (MFR 30.5 ml/h; TMFR 11.5 h). VFA production after 8 hours of incubation was the highest for simple sugars and inulin-N, low for inulin-C, and the lowest for β-glucan (p < 0.05). The molar proportion of acetic acid was lower in sugars and inulin-N than in inulin-C and β-glucan, which had the lowest molar proportion of butyric acid (p < 0.05)