Effect of Clove Oil Treatment on in vitro Dry Matter Digestibility and Metabolizable Energy Value of Wheat Straw

Objective: This study aimed to determine the effect of clove oil on in vitro dry matter digestibility (DMD) and metabolizable energy (ME) values of wheat straw. Material and Methods: In the research, clove oil (66.6% eugenol) was treated with wheat straw at different doses (0, 50, 100, 200 ppm) and hours (1, 3, 5, 7, 9, 12). Firstly, in vitro cellulase method was applied in the study. In the application of the method, pepsin (2000 FIP-U/g) and also the cellulase enzyme obtained from Trichoderma viride (Onozuka R-10, 1 U/mg activity) were used. Then from obtained values, the DMD value of the feed and the amount of organic matter soluble in the enzyme (ELOS) were found and the in vitro ME values were calculated. Results: Clove etheric oil depending on the increasing dose was increased DMD, ELOS and ME values of wheat straw (P<0.01). Accordingly, clove oil treatment, increased the DMD, ELOS and ME values of the straw from 37.17% to 53.92%, from 22.31% to 39.45% and from 7.53 MJ/kg to 8.13 MJ/kg, respectively (P<0.01). The highest values for these parameters were obtained at 200 ppm dose and 5 hours (P<0.01, P<0.05). Conclusion: As a result, clove oil treatment in wheat straw has an important potential effect in increasing the in vitro digestion and energy value of feed. However, the results of the study should be supported by more detailed studies, especially in vivo studies.