Whole crop barley was harvested (32.5% DM), chopped and ensiled for 30 days in laboratory silos (n= 4) as untreated (UT) or treated with SM (50 g/kg of DM) or BP (50, 75 and 100 g/kg; BP5, BP7.5 and BP10, respectively) or a mixture of SM and BP (50:50 or 50:100 g/kg sugar beet molasses: dried sugar beet pulp; MB5 and MB10, respectively). The pH of the aqueous silage extract was recorded, then, NH3-N concentration was determined in acidified silage extract (5 ml of the extract + 5 ml of 0.2 N HCl) using a distillation method. The ruminal degradable parameters of DM of the silages were determined using an in situ procedure. Four sheep (44±3 kg live weight) fitted with rumen fistulae were used. Bags (10 × 12 cm) were made of polyester nylon cloth with a pore size of 52 µm. About 5 g DM of each sample was placed in each bag, and four bags per each sample were incubated for each time (0.0, 2, 4, 8, 16, 24, 48, 72, 96 h). For zero time, bags were washed using cold tap water. After each incubation, bags were washed in cold running water and dried in oven (60 °C, 48 h), then weighted to determine DM disappearance. The equation of P= a+b (1-e -ct ) was applied to determine the coefficients (a= quickly degradable fraction, b= slowly degradable fraction, c= fractional degradation rate constant). Silages treated with SM as alone or combined with BP had a significant (P< 0.05) lower pH (UT= 4.07, M5= 3.70, MB5= 3.71) compared with those of the un-supplemented. The supplementation caused an increase in rapidly degradable fraction and a decrease in slowly degradable fraction of silages.

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