Relationship between faecal scoring and in vitro digestibility of the diet in buffalo cows

Abstract

Samples of faeces were collected monthly for 3 and 2 times respectively from 12 lactating and 12 dry buffalo cows. The samples, evaluated for faecal scoring (Faecal Consistency, FC and Undigested Fractions, UF), were used as inocula (dilution 1:2 with anaerobic medium) to determine in vitro digestibility (IVTD) of organic matter, crude protein and NDF after 48 h of incubation using the apparatus DaisyII ANKOM. The IVTD of organic matter was significantly higher (46.5 vs 32.9 and 33.0 %, P<0.01) in lactating (FC = 3) than in dry animals (FC = 3.5 and 4), probably due to the higher fibre content of diet of the latter. The higher crude protein digestibility obtained for dry animals (59.1 vs 65.6 and 66.4 %, respectively for FC = 3 – 3.5 and 4, P<0.01) could be due to the higher efficiency of nutrient utilisation of the micro organisms. Faeces with higher UF showed significantly higher organic matter digestibility (35.6 vs 38.8 %, respectively for UF=1 and 2, P<0.01). Finally, the equations able to estimate IVTD from faecal scores were always statistically significant (P<0.01) and the highest R2 value was reached for organic matter (about 0.83). The latter results suggest that the combination of FC and UF scores allows a good estimation of in vitro digestibility of organic matter, crude protein and NDF.