| Abstrakt: |
Soaking wheat straw in alkaline solutions prepared from wood ashes was evaluated as a potential treatment for improving rumen digestibility. Solutions of wood ashes, ranging in concentrations from .5 to 50% (w/v) were studied for pH, titratable alkalinity and mineral composition. In vitro dry matter disappearance (IVDMD) and in vitro organic matter disappearance (IVOMD) of wheat straw were improved (P<.05) after soaking 6 h in a 30% alkaline solution of wood ashes (ASWA). Sequential use of the same ASWA, diluting back to volume after each treatment, did not decrease its effectiveness in increasing digestibility, at least through 15 sequential soakings. Nine 2-yr-old castrated male goats (six LaManches and three Alpines) were used in a 3 × 3 Latin square with three replicates to evaluate the effect of ASWA treatment of straw on digestibility. Straw treated with 30% ASWA was compared with untreated or NaOH-treated straw in diets containing 86% wheat straw and 14% supplement. Digestibility of dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were all greater (P<.05) for the ASWA-treated straw diet as compared with the NaOH- and untreated-straw diets. Organic matter (OM) digestibility was not different between ASWA- and NaOH-treated straw diets, both of which were greater (P<.05) than the control diet. Dry matter intake of the ASWA-treated straw diet was greater (P<.05) than intake of the other two diets. Fecal water ouptut was not affected by treatment, whereas urine output volumes were different (P<.05) among the three diets (4,893, 7,194 and 2,486 ml/period for ASWA, NaOH and control, respectively). The results of these experiments demonstrate that treatment of wheat straw with ASWA effectively improves fiber utilization by ruminants. |
