The knowledge of digestibility of forages and diets is essential to optimize the use in the dairy cow rations. The assessment of the quality of forages and diets involves the use of ruminal fluid collected from cannulated animals. In recent years, however, the world of research has been evaluating alternative and less invasive sources of inoculum compared to rumen fluid. In this study, the DiSAA researchers evaluated the potential of several faecal inocula, collected from cows fed diets with different forage basis, for the estimation of fiber digestibility. The experimental fecal inocula gave values similar to the traditional inoculum (rumen) for long time incubations; in addition, the type of diet administered influenced the microbial activity of the inoculum and therefore the digestibility values.
The results obtained open very interesting perspectives for the estimation of the digestibility of the fiber which could reduce the use of cannulated animals for long time incubations (240 -360 h). This approach would also allow to several laboratories to estimate the in vivo digestibility of rations administered in commercial farms, with important practical effects for the farmers.
Figure. Relationship between uNDF values obtained by faecal inoculum (FL-GLH) and rumen inoculum (RD-GH) in long time in vitro incubations (240 h a; 360 h b).
Chiaravalli, M.; Rapetti, L.; Rota Graziosi, A.; Galassi, G.; Crovetto, G.M.; Colombini, S. Comparison of Faecal versus Rumen Inocula for the Estimation of NDF Digestibility. Animals 2019, 9, 928.