The Effects of Xylose Treatment on Rumen Degradability and Nutrient Digestibility of Soybean and Cottonseed Meals

Two trials were conducted to evaluate the effect of xylose treatment on rumen degradability characteristics of DM, OM and CP and in vivo digestibility of DM, OM, CP and crude fiber (CF) of soybean meal (SBM) and cottonseed meal (CSM). In Trial 1, three ruminally cannulated Merino rams were used. Xylose treatments at both levels, 0.5 and 1%, decreased effective degradability of DM, OM and CP of SBM, whereas 0.5 and 1% xylose treatment of CSM did not show any effect on effective degradability of DM, OM and CP. By contrast, maximum potential degradabilities of DM, OM and CP of CSM seemed to be increased by 1% xylose treatment. It was concluded that xylose treatment was effective in protecting SBM proteins from degradation in the rumen, but the same treatment was not so effective for CSM protein. In trial 2, three Merino rams were used. With treatments, DM, OM, CP and CF digestibilities of SBM and CSM were not changed. Crude fiber digestibility was numerically increased by the treatments of 0.5 and 1% xylose of both SBM and CSM compared to untreated SBM and CSM but differences were not significant. In conclusion SBM proteins can be effectively protected from degradation in the rumen by xylose treatment, without negatively affecting in vivo digestibility of protein, whereas xylose treatment appeared to be less effective on protecting of CSM proteins. (Asian-Aust. J. Anim. Sci. 2006. Vol 19,