Effect of Lignin Reduction in Ammoniated Corn Stover on In-Vitro Digestibility of Dry Matter and Organic Matter

Abstract

Corn stover is an agricultural by-product with the potential to be ruminant feed; however, its utilization is often limited by its high lignin content, which impairs digestibility. This study aims to evaluate the effect of lignin content in corn stover following ammonia treatment with urea addition on dry matter digestibility (DMD) and organic matter digestibility (OMD). The research employed a Completely Randomized Design (CRD) with four urea doses (0%, 2%, 4%, 6%) and four replicates, using in-vitro analysis to assess DMD and OMD values. Data analysis was conducted using the SAS (Statistical Analysis System) application. The results showed that ammonia treatment effectively reduced lignin content from 8.61% in the control (T1) to 3.31% in the highest urea dose treatment (T4). Both DMD and OMD increased, with the highest values obtained in the 4% urea treatment (T3), where DMD was 60.26% and OMD was 65.47%. The significant reduction in lignin facilitated improved digestibility by loosening lignocellulose bonds, allowing rumen microbes to degrade fiber more efficiently. This study concludes that the decrease in lignin content due to the addition of urea at varying levels (0-6%) during the ammonia treatment of corn stover, from 8.61% to 3.31%, positively impacts the increase in DMD (from 45.87% to 60.26%) and OMD (from 52.53% to 65.47%). The 4% urea treatment produced the best digestibility results, with lignin content reduced to 3.58%, yielding the highest DMD and OMD values. Further research is needed to evaluate the impact of this treatment on rumen fermentation characteristics.