This study was conducted to evaluate the germination rate, chemical composition, and in vitro digestibility of sprouted barley (Hordeum vulgare L.) and wheat (Triticum aestivum L.) sprouts depending on cultivar and growth duration. Four cultivars Keunalbori1ho, Saekeumkang, Arijinheuk, and Jokyoung were tested under hydroponic and nutrient solution conditions. The germination rate was significantly higher under hydroponic conditions compared to nutrient solution treatment. Sprouts were harvested at 0, 4, 6, and 8 days for subsequent analysis. Chemical compositions, such as dry matter (DM), crude protein (CP), ether extract (EE), and crude ash (CA), were analyzed following AOAC (2005) protocols, while neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents were determined according to the method of Van Soest et al. (1991). In vitro digestibility was assessed by incubating ground samples with rumen buffer in DaisyII incubators for 48 h. At day 6 of growth, Keunalbori1ho showed the highest NDF and ADF concentrations (48.6% and 26.2%), reflecting its high structural fiber and the lowest digestibility (IVDMD 52.2%, IVNDFD 37.2%). However, it maintained consistent nutritional characteristics across all growth stages, suggesting potential as a stable forage source. In contrast, Saekeumkang exhibited the highest IVNDFD (59.1%) along with relatively low NDF (30.5%) and ADF (16.7%) values (p<0.05), indicating superior digestibility likely attributed to a simpler cell wall structure and higher NFC availability. Notably, digestibility sharply declined by day 8, implying that the optimal harvest window lies around day 6. Therefore, this study suggests that the cultivars Keunalbori1ho and Saekeumkang possess complementary strengths in terms of chemical composition and digestibility, underscoring the importance of optimizing cultivar selection and harvest timing to enhance the potential of cereal sprouts as high quality forage.

This study aimed to estimate the rumen fermentation characteristics and greenhouse gas emissions of major domestic feed sources for Hanwoo. Five feed sources mainly used in South Korea were selected: corn meal (CM), soybean meal (SM), wheat flour (WF), palm kernel cake (PKC), and corn distiller’s dried grains with soluble (DDGS). These feed sources were purchased from a commercial feed company. For 24 h rumen incubation, each feed source (0.3 g) was placed into the incubation bottle with the rumen mixture (30 mL) in quadruplicates. After incubation, total gas production was measured and sub-sampled for CO2 and CH4 analyses, and the bottle content was centrifuged for rumen fermentation characteristics and in vitro dry matter digestibility (IVDMD). Crude protein content was highest in SM and lowest in CM. Ether extract content was highest in DDGS and lowest in SM, while neutral detergent fiber and acid detergent fiber contents were highest in PKC and lowest in CM. Propionate content was highest in DDGS, and butyrate and A:P ratio contents were highest in PKC (p<0.05). Total gas emission (mL/g DMD) was lowest in SM and DDGS, while CH4 emission (mL/g DMD) was lowest in DDGS (p<0.05). Therefore, this study concluded that DDGS could be an alternative feed source to reduce methane emissions.

This study was conducted to estimate the effects of the forage process on rumen fermentation characteristics and greenhouse gas emissions of rye. Rye was grown at the Taeyoung Livestock farm and harvested at the heading stage. The harvested rye (5 kg) was sub-sampled for fresh forage, hay, and silage in triplicates. The sub-sampled rye was freeze-dried or air-dried for fresh forage or rye hay, respectively. For rye silage, the sub-sampled rye forage was ensiled into a 10 L mini bucket silo and stored for 90 days. For 72 h rumen incubation, each forage (0.3 g) was placed into the incubation bottle with the rumen mixture (30 mL) in quadruplicates. After the incubation, total gas was measured and sub-sampled for CO2 and CH4 analyses, and the bottle content was centrifuged for in vitro digestibilities of dry matter (IVDMD) and neutral detergent fiber (IVNDFD), and rumen fermentation characteristics. Silage had higher crude protein, crude ash, and acid detergent fiber concentrations than fresh forage and hay but lower non-fiber carbohydrates and relative feed value (p<0.05). And, silage had higher lactic acid bacteria than the other forages but lower pH (p<0.05). After 72 h incubation in the rumen, fresh forage had higher IVDMD and butyrate content than the other forages (p<0.05). However, silage had higher rumen pH and propionate content than the other forages but lower A:P ratio (p<0.05). Regarding greenhouse gases, silage had lowest total gas (mL/g DMD and NDFD) and CH4 (mL/g DMD and NDFD) emissions, while fresh forage had lowest CO2 (mL/g DMD) emission (p<0.05). Therefore, this study concluded that the ensiling process of rye can effectively mitigate greenhouse gas emissions of Hanwoo.