Manufacturing and Feed Value Evaluation of Wood-Based Roughage Using Lumber from Thinning of Oak and Pitch Pine

ABSTRACT The objective of this study was to manufacture the wood based roughage using lumber from thinning of oak andpitch pine (Pinus rigida). And the study also aimed to investigate a feed value evaluation of wood based roughages.To investigate the optimization condition of steam-digestion treatment for roughage, the wood chips of oak and pitch pine were steam-digestion treated at 160 ℃ under pressure 6 atm depending on treatment times (60 min, 90 min and 120 min) followed by the content of essential oils analyzed. The essential oil content of steam-digestion treated rough-ages for 90 min and 120 min were under 0.1 mL/kg. The evaluation of feed value was carried out from steam-diges-tion treated roughages for 90 min through feed chemical composition analysis, NRC (National research Council) model-ing, ruminal degradability analysis and relative economic value analysis. The feed chemical compositions including DM(dry mater), CP (crude protein), EE (ether extract), NDF (neutral detergent fiber), ADF (acid detergent fiber), ADL (acid detergent lignin), NFC (nonfiber carbohydrate) in oak roughage were 95.4, 1.36, 3.11, 90.05, 83.85, 17.33, 6.50%,respectively, and in pitch pine roughage were 94.37, 1.33, 5.48, 87.89, 86.88, 30.56, 6.32%, respectively. Both rough-ages showed low level of protein and very high level of NDF. The TDN (total digestible nutrient) levels using NRC(2001) model in oak and pitch pine roughages were 40.55, 31.22%, respectively. The ruminal in situ dry matter de-gradability was higher in oak roughage (23.84%) than in pitch pine roughage (10.02%). The economic values of oakand pitch pine roughages were 235, and 210 ₩, respectively.Keywords : wood-based roughage, oak, Pinus rigida, essential oil, chemical composition, total digestible nutrient, ruminal degradability