Published online by Cambridge University Press: 27 February 2018
Inter- and even intra-species variability exists in the ability of rumen inocula to digest forages using in vitro techniques. Differences in fermentation patterns between animal species may be due to the presence of different species within the microbial populations and/or to the fermentative capacity of the microflora (Sunvold et al., 1995). Several authors have reported that the host species affects the rumen microflora which therefore influences the in vitro activity of rumen fluid, even if two host species are given the same diet. Grant et al. (1974) concluded that after a sufficiently long adaptation period to the diet, there was no longer any significant difference between the rumen fluid from buffalo and cows. However, the results obtained by other authors (di Leila et al. 1995; Puppo et al., 1995) are in disagreement with these findings. The in vitro cumulative gas production technique (Theodorou et al., 1994), is increasingly being used as a method of food evaluation, by comparing the fermentability of different foods. One of the greatest sources of variation for this kind of method is due to differences in inocula. An experiment was carried out to determine whether rumen fluid from buffalo and cows given a similar diet, led to similar results for the evaluation of the same foods.