Tannins at low concentrations can confer nutritional advantages to ruminants by reducing protein degradation in the rumen and increasing the flow of protein and essential amino acids to the intestine. However, higher concentrations of condensed tannins have deleterious effects on animal performance, digestibility and voluntary intakes. Polyethylene glycol (PEG), react preferentially with condensed tannins and prevents the formation of tannin-protein complexes. The aim of this study was to evaluate the effects of feeding pistachio hull (PH, source of tannin) and PEG supplementation on feed intake and nutrients digestibility in Saanen dairy goats. Nine Saanen dairy goats were used in a 3 × 3 Latin square design with 21-d periods, including 14 d of adaptation followed by 7 d of sampling. Three treatments were formulated: T1) Control, without PH, T2) 30% PH (DM basis) that provided 18.1 g condense tannin per kg DM of diet and T3) 30% PH + 1% PEG (DM basis). In T2 and T3 PH was replaced with alfalfa hay. Statistical analysis was performed using the MIXED procedure of SAS (P < 0.05). Dry matter intake (DMI), DMI per body and metabolically weight were not affected in the experimental diets. Organic matter intake (OMI), OMI per body and metabolically weight, ADF, NDF and crude protein intake were significantly decreased in 30% PH (T2) and with the addition of PEG in T3 were significantly increased. Fat intake in T2 (168.40 g/d) and T3 (175.13 g/d) in comparison to Control (150.14 g/d) were significantly increased. DM, ADF and NDF apparent digestibility weren’t significantly affected by the diets, but in T2 had a tendency to decrease and with the addition of PEG in T3 showed an increasing trend. OM and CP apparent digestibility were significantly decreased in T2 and with the addition of PEG in T3 were significantly increased. Fat apparent digestibility in T2 (84.95%) and T3 (85.98%) vs. Control (83.91%) was significantly increased. This study has shown that pistachio hull can replace alfalfa hay in diets for goats when PEG is given as a supplement.

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