NUTRITIVE VALUE OF STEAM-TREATED CORN STOVER

Abstract

Corn stover, ground through a 1.6-cm screen, was steam-processed at 16.2 kg/cm2 and 205 °C for 15 min. Control and treated stover were evaluated for intake and digestibility of organic constituents with eight wether lambs in a single crossover design. Prior to feeding, water was added to control corn stover to approximate the moisture content of treated stover and to reduce dustiness. Soybean meal was added to both rations and, in addition, urea was added to treated stover to attempt to make up for nitrogen rendered unavailable by treatment. Steam treatment increased (P < 0.05) ADF, ADIN, permanganate lignin and acetic acid. Dry matter intake increased (P < 0.05) by 55% with steam treatment. Treatment also increased (P < 0.05) apparent digestibilities of organic matter, energy, non cell wall contents and cellulose but decreased (P < 0.05) digestibilities of NDF and ADF. The extent of improvement in energy digestibility was limited by heat damage due to processing. Modifications in treatment conditions should reduce this effect.