Ⅰ. INTRODUCTION
Triticale (× Triticosecale Wittmack) is an interspecific cereal derived from wheat and rye and it has considerable potential as a forage crop because of its dry matter yield, adaptability and suitability for forage production (Ayalew et al., 2018;Ferreira et al., 2025;Ilavenil et al., 2025). The nutritive values of the triticale are strongly influenced by sowing dates, harvest maturity with advancing maturity generally associated with increased structural carbohydrates and reduced protein (Coblentz at al., 2022;Ozkurt, 2025). Recent studies have demonstrated substantial differences in crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch concentrations among triticale harvested at different growth stages (Galyon et al., 2026;Schultz et al., 2025). Ensiling preserves cereal forages through microbial fermentation, primarily by lactic acid bacteria (LAB), which produce organic acids mainly lactic acid and acetic acid. It can reduce pH of the silages, thereby restricting undesirable microbial growth (Tuovinen et al., 2025). In triticale, fermentation quality is influenced by forage maturity and moisture content, and LAB population at ensiling. Recent research has shown that these factors affect pH, organic acid production, nutrient composition, and microbial community structure (Lan et al., 2026). Triticale silage may serve as an alternative or complementary forage to conventional crops such as corn silage. Recent studies indicate that harvest maturity and dietary inclusion may influence nutrient digestibility and animal performances (Galyon et al., 2026;Schultz et al., 2025). However, information on changes in fermentation characteristics and nutritional composition of baled triticale silage during prolonged storage remains limited. Therefore, this study evaluated variation in total dry matter yield between cultivation years and changes in fermentation characteristics and nutritional composition of baled triticale silage during 3, 6, 9, and 12 months of storage, including pH, organic acids, crude protein, NDF, ADF, and total digestible nutrients (TDN).
Ⅱ. MATERIALS AND METHODS
1. Experimental field
The experiment was conducted in Cheonan, Chungcheongnam-do Province, Republic of Korea, at 36.931739° N latitude and 127.106166° E longitude. It has a distinct seasonal climate with relatively high-temperatures from late spring to early autumn and cold winters. The average temperature in August, the hottest month was approximately 29.9°C, whereas February was the coldest month, with an average temperature of –5.8 °C. The main rainy period started from June to September.
2. Triticale cultivation
Triticale was cultivated in experimental field covering 3ha in 2024 and 2025. The seeding rate was 180 kg/ha. Triticale was sown using a narrow-row seeding method with a row spacing of 25 cm and an intra-row spacing of 5 cm. The crop was sown in early October each year and harvested in early May. Basal fertilization was applied at rates of 59 kg N ha−1, 74 kg P ha−1, and 39 kg K ha−1. An additional 59 kg N ha−1 was applied as a topdressing in early March and triticale harvested at the heading stage. The annual yield of triticale was determined from three randomly selected areas within the 3ha experimental field. Each sampling area was measured 3 m × 4 m area (12 m2) and it was considered as an independent replicate. The harvested samples were dried at 65°C to determine their moisture content, and the measured yields were converted to dry matter (DM) yield.
3. Silage production by bale silage method
After harvesting, the triticale forage wilted under field conditions until the desired dry matter content was reached (DM 57.7%). The wilted forage was then collected, mechanically baled, and prepared as 12 silage bales. The bales were wrapped with polyethylene film to establish anaerobic conditions. A microbial inoculant (Top Silage, manufactured by Jeongnong Bio, Korea) was applied during ensiling according to the manufacturer's protocol. The wrapped bales were stored under field conditions for 12 months. Three different bales were randomly assigned to each sampling period (3, 6, 9, and 12 months), resulting in three independent bale replicates per storage period. At each sampling time, the three previously unopened bales assigned to that period were opened, and approximately 500 g of silage was collected from the center of each bale using a clean sampling probe. The collected samples were used for subsequent analyses.
4. Analysis nutrient compositions and organic acid profiles
For fermentation analysis, 10 g of each silage sample was mixed with 90 mL of distilled water and shaken for 1 h using an orbital shaker. The pH was subsequently measured using a glass-electrode pH meter (Thomas Scientific, NJ, USA). Organic acids, including lactic, acetic, and butyric acids, were analyzed using high-performance liquid chromatography (HPLC) and gas chromatography (Jung et al., 2024). The CP (AOAC, 1990b), NDF, and ADF concentrations were determined (Van Soest et al., 1991).Total digestible nutrients (TDN) were estimated from acid detergent fiber (ADF) using the following equation: , where ADF is expressed as a percentage of dry matter (Seo et al., 2010;Holland et al., 1990).
5. Statistical analysis
Statistical analyses were performed using SPSS version 16.0 (SPSS Inc., Chicago, IL, USA). The dry matter (DM) yield of triticale was compared between the two cultivation years (2024 and 2025) using an independent-samples t-test. Differences in silage fermentation characteristics among storage periods (3, 6, 9, and 12 months) were analyzed using one-way analysis of variance (ANOVA). A p-value < 0.05 was considered statistically significant.
Ⅲ. RESULTS AND DISCUSSION
1. Comparative yield of triticale cultivation for the years 2024 and 2025
The total dry matter (TDM) yield of triticale differed between the two cultivation years (Fig. 1). In 2024, the TDM yield was 9,718 kg/ha, whereas it decreased to 8,237 kg/ha in 2025, it represented a 15% reduction. The observed year-to-year variation may reflect differences in growing conditions; however, environmental variables such as temperature, precipitation, soil moisture, and nutrient availability were not directly measured in the present study, and therefore their specific contributions to the observed yield difference cannot be determined. Previous research has shown that forage yield and nutritional composition of small-grain forages can be influenced by growing conditions and harvest maturity, with advancing maturity generally increasing dry matter yield while affecting fiber and protein concentrations (Coblentz et al., 2018;Ferreira et al., 2025). The mean TDM yield across the two years was 8,977.5 kg/ha. Although the results indicate that triticale produced considerable dry matter yield in both years, the two-year observation period is insufficient to establish long-term yield stability. Therefore, further multi-year studies incorporating environmental and agronomic measurements are needed to better characterize the effects of annual growing conditions on triticale forage yield.
2. Fermentation characteristics of triticale silage at different storage periods
Fermentation characteristics of ensiled silage varied with different storage periods (Table 1). The silage pH decreased from 5.69 ± 0.15 at 3 months to 5.43 ± 0.10 at 6 months, increased to 5.81 ± 0.35 at 9 months, and then decreased to 5.29 ± 0.33 at 12 months (p<0.05). pH is an important indicator of silage quality. In general, the ideal pH for silage fermentation is between 3.8 and 4.2, which is considered a benchmark for well-preserved silage (Ahmadi et al., 2019;He et al., 2018). However, in the present study, the pH of the fermented silages ranged from 5.29 to 5.81, which was higher than the ideal pH range for well-fermented silage. But, the relatively high dry matter content of the forage at ensiling (57.7% DM) may have contributed to the limited acidification observed in the current study. High dry matter content could restrict adequate compaction and reduce LAB activity, thereby limiting organic acid production and subsequent pH decline. Lan et al. (2026) reported that moisture content significantly affected triticale silage fermentation, with forage ensiled at 70% moisture resulting in higher lactic acid production and lower pH than forage ensiled at a lower moisture content (Lan et al., 2026). Lactic acid concentration increased substantially during the first 6 months, from 4.56 ± 0.49% DM at 3 months to 10.20 ± 0.27% DM at 6 months (p<0.05). Thereafter, lactic acid concentrations remained relatively stable, at 9.14 ± 0.53% and 9.29 ± 0.51% DM at 9 and 12 months, respectively. The highest lactic acid concentration was observed at 6 months of storage (p<0.05), suggesting that the most active phase of lactic acid fermentation occurred during this stage of storage, followed by stabilization. This pattern indicates that most of the available water-soluble carbohydrates (WSC) had likely been utilized during this fermentation period, resulting in relatively limited changes in lactic acid concentration during prolonged storage (Zeng et al., 2020;Soundharrajan et al., 2023). Acetic acid concentrations remained low throughout storage, ranging from 0.40 to 0.54% DM, while propionic acid concentrations remained low (0.025–0.14% DM). The predominance of lactic acid and the relatively low concentrations of other organic acids indicate that lactic acid fermentation was the major fermentation pathway in the triticale silage. In contrast, butyric acid concentrations ranged from 0.04 to 0.16% DM, with the highest concentration observed at 9 months of storage. The increase in butyric acid at 9 months may indicate a limited shift toward secondary fermentation, potentially associated with clostridial activity. Clostridia can utilize fermentable substrates and, under favorable conditions, convert lactic acid and other fermentation products into butyric acid, resulting in nutrient and dry matter losses and deterioration of silage quality (Shao et al., 2002, Kung et al., 2018). However, the relatively low butyric acid concentration observed in the present study (0.16% DM) suggests that undesirable fermentation was limited and did not become the predominant fermentation pathway. Moreover, the absence of a continued increase in butyric acid at 12 months suggests that this change was not indicative of progressive deterioration during extended storage. Lactic acid is the principal organic acid produced by LAB during ensiling and plays an important role in reducing silage pH and restricting undesirable microbial activity (Kung et al., 2018). Therefore, the relatively high and stable lactic acid concentration, together with the low concentrations of acetic, propionic, and butyric acids, suggests that fermentation quality was generally maintained throughout storage. Variations in organic acid production may also be related to harvest maturity and moisture content, which influence fermentable substrate availability and LAB activity during ensiling (Lan et al., 2026;Ilavenil et al., 2022).
3. Nutritional composition
The nutrient composition of baled triticale silage was influenced mainly by storage duration, particularly in terms of CP (Table 2). The CP content increased slightly from 10.14% at 3 months to 11.35% at 6 months, but subsequently decreased to 9.23% and 8.82% at 9 and 12 months, respectively (Table 2). The CP values at 9 and 12 months were significantly lower than those at 3 and 6 months (p<0.05), indicating a reduction in CP concentration during prolonged storage. A previous study reported that prolonged storage of ensiled silage could alter its CP content (Xin et al., 2022). In contrast, NDF and ADF contents did not differ significantly among storage periods (p>0.05), although NDF ranged from 64.25% to 69.01% and ADF from 37.59% to 40.03%. Similarly, TDN remained relatively stable, ranging from 57.27% to 59.20%, with no significant differences among storage durations (p>0.05), suggesting that the estimated energy value remained comparatively stable during storage. Prolonged ensiling induced progressive proteolysis, converting true proteins into peptides, free amino acids, and ammonia-N. Subsequent deamination and potential volatilization or physical loss of nitrogen may have contributed to the observed decline in crude protein concentration during extended storage (Sikora et al., 2021;Der Bedrosian et al., 2012). Overall, the results indicate that storage duration significantly reduced CP, whereas TDN level remained relatively stable over the 12-month fermentation period.
Ⅳ. CONCLUSION
Triticale produced a considerable dry matter yield, with an average TDM yield of 8,977.5 kg ha−1 across 2024 and 2025, although yield varied between years. The ensiling preservation study revealed that during 12 months of bale storage, lactic acid increased markedly during the first 6 months and remained relatively stable thereafter, while acetic and propionic acid concentrations remained low. No significant variations were observed in NDF or ADF concentrations during storage, whereas CP levels varied significantly with increasing storage duration. Overall, triticale showed good potential as a forage crop and maintained comparatively stable nutritional characteristics during prolonged storage. Optimizing harvest maturity, moisture content, and ensiling conditions may further improve fermentation quality and nutrient preservation.
