Alkali treatment of straw for ruminants. II. Nutritive value of straw ensiled after alkali treatment

In the first of two experiments barley straw was treated with a 16% solution of $\text{NaOH}\text{t}$ dry matter (DM) and ensiled for one year. It was satisfactorily preserved, having a pH of 10 and counts of 10⁴ mesophilic bacteria and 10³ fungal propagules per g. When this straw was mixed with concentrates (50:50, DM basis) and given to sheep, DM intake and digestibility were 102 g/kg W^0.75 per day and 67.3%. Comparable values for a diet based on freshly-treated straw were 88 g and 66.5%.In the second experiment, a 6-tonne batch of alkali-treated barley straw was ensiled for 2–4 months, then mixed with 40% concentrates and given to 370-kg steers for 66 days. Intake and growth rate were 10.23 and 1.08 kg/d, compared with 9.06 and 1.00 kg/d for steers given a diet based on freshly-treated straw. The latter diet was less digestible (for sheep) than the former.It is concluded that the feeding value of stored straw is as high as that of freshly-treated material.