Comparison of caecal and faeces fermentation characteristics of ostrich by in vitro gas production technique

To compare caecal and faecal fermentation characteristics, ostrich caecal content (CI) and faeces (FI) were used as inocula for an in vitro gas production trial in which four substrates (dehydrated alfalfa, alfalfa hay, maize and a commercial concentrate) were tested. The fermentation characteristics (degraded organic matter, OMd; potential gas production, A; acetate; branched chain proportion, BCP) were studied by inoculum and substrate. CI and FI showed significant differences for almost all the fermentation parameters, and CI had higher values than FI for OMd (76.83 vs. 72.79%, p<0.01), A (250.3 vs. 229.3 ml/g, p<0.01), acetate (57.91 vs. 53.20 mmol/l, p<0.01) and BCP (0.031 vs. 0.027, p<0.05). CI and FI showed differences in carbohydrates and protein fermentation, but the interaction between the tested effects was not significant. The regression equations to estimate caecal fermentation characteristics from faeces suggest the possibility to use faeces as inoculum alternative to faeces. © 2011 Taylor & Francis.