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.

The present study estimated rumen fermentation characteristics and greenhouse gas emissions of different forages. Alfalfa, timothy, tall fescue, Italian ryegrass, and rice straw as the main forage sources for Hanwoo were used in the present study. Crude protein was highest in alfalfa but lowest in rice straw (p<0.05). Ether extract was higher in alfalfa and Italian ryegrass than in the other forages (p<0.05). Crude ash was highest in rice straw but lowest in tall fescue (p<0.05). Neutral detergent fiber was highest in tall fescue but lowest in alfalfa (p<0.05). Acid detergent fiber was highest in Italian ryegrass and rice straw but lowest in alfalfa (p<0.05). In vitro digestibilities of dry matter (DMD) and neutral detergent fiber (NDFD) were highest in timothy but lowest in rice straw (p<0.05). Rumen pH was highest (p<0.05) in alfalfa, while ammonia-N was higher (p<0.05) in alfalfa and Italian ryegrass than in the other forages. Total volatile fatty acid was highest (p<0.05) in timothy, while acetate and propionate were highest (p<0.05) in alfalfa and rice straw, respectively. Acetate to propionate ratio was higher (p<0.05) in alfalfa, timothy, and Italian ryegrass than in rice straw. Rice straw had lowest total gas (mL) (p<0.05) but highest its per DMD and NDFD. Rice straw had higher (p<0.05) CO2 (per DMD and NDFD) compared to alfalfa (per DMD and NDFD), timothy (per DMD and NDFD), tall fescue (per NDFD), and Italian ryegrass (per DMD). Again, rice straw had higher (p<0.05) CH4 (per DMD and NDFD) compared to timothy (per DMD and NDFD) and tall fescue (per NDFD). Therefore, this study indicates that timothy has a higher nutrient digestibility and volatile fatty acid in the rumen leading to a reduction of greenhouse gas emission.

This study was aimed to isolate bacterial inoculants producing chitinase and evaluate their application effects on corn silage. Four corn silages were collected from four beef cattle farms to serve as the sources of bacterial inoculants. All isolates were tested against Fusarium graminearum head blight fungus MHGNU F132 to confirm their antifungal effects. The enzyme activities (carboxylesterase and chitinase) were also measured to isolate the bacterial inoculant. Based on the activities of anti-head blight fungus, carboxylesterase, and chitinase, L. buchneri L11-1 and L. paracasei L9-3 were subjected to silage production. Corn forage (cv. Gwangpyeongok) was ensiled into a 10 L mini silo (5 kg) in quadruplication for 90 days. A 2 × 2 factorial design consists of F. graminearum contamination at 1.0104 cfu/g (UCT (no contamination) vs. CT (contamination)) and inoculant application at 2.1 × 105 cfu/g (CON (no inoculant) vs. INO (inoculant)) used in this study. After 90 days of ensiling, the contents of CP, NDF, and ADF increased (p<0.05) by F. graminearum contamination, while IVDMD, acetate, and aerobic stability decreased (p<0.05). Meanwhile, aerobic stability decreased (p<0.05) by inoculant application. There were interaction effects (p<0.05) on IVNDFD, NH3-N, LAB, and yeast, which were highest in UCT-INO, UCT-CON, CT-INO, and CT-CON & INO, respectively. In conclusion, this study found that mold contamination could negatively impact silage quality, but isolated inoculants had limited effects on IVNDFD and yeast.

The present study investigated the effects of forage cutting and baler mixing on the chemical compositions, fermentation indices, and aerobic stability of whole crop rice (WCR) haylage. The WCR (“Youngwoo”) was harvested at 48.4% dry matter and ensiled into a 300 kg bale silo with forage cutting (whole crop without cutting vs. 5 cm of cutting length). The WCR forages were ensiled without baler mixing process (CON) or with (MIX). The concentrations of dry matter, crude protein, ether extract, crude ash, neutral detergent fiber, and acid detergent fiber of whole crop rice before ensiling were 48.4, 9.70, 2.57, 6.11, 41.2, and 23.5%, respectively. The forage cutting did not affect the chemical compositions, fermentation indices, microbes, and aerobic stability of WCR haylage (p>0.05). The CON haylages tend to be higher in NDF content (p<0.10). The MIX haylages had lower in lactate (p=0.019), and lactate:acetate ratio (p<0.001). The MIX haylages had higher in lactic acid bacteria (LAB) (p=0.010). Therefore, this study concluded that the fermentation quality of WCR haylage improved by baler mixing, but had no effects by forage cutting.