Fermentation parameters and total gas production of equine caecal and faecal inocula

Abstract

This study intended to compare the fermentative activity of equine caecal and faecal inocula using the gas production technique. For that purpose, 2 feeds (oats and barley) were used. Caecal and faecal samples were collected from 2 canulated geldings fed with meadow hay (80%) and concentrate (20%) offered as two equal meals per day. Samples of caecal fluid and fresh faeces were collected 2 hours after the morning feed into pre-warmed flasks filled with CO2. Feed samples were incubated in 60 ml of buffered caecal or faecal fluid, in duplicate in 3 series performed on different days for each type of inoculum. The parameters pH, NH3-N and total VFA were measured after 96 h of fermentation. Gas production was recorded for 96 h using a fully automated system. Data were analyzed by ANOVA using feeds and inoculum as the main factors. Differences between feeds concerning pH (P<0.001), total VFA (P<0.001), NH3-N (P<0.001), acetate/propionate ratio (P<0.001) were observed as a result of different types of fermentation patterns. The type of inoculum showed differences in B (time of incubation at which half of the asymptotic gas production has been formed) parameter of gas production (P<0.05). Results presented in this study indicate similar fermentation patterns between faecal and caecal inocula.