Effect of Homo- and Heterofermentative Silage Additives on the Quality and In Vitro Rumen Digestibility of Two Different Triticale Cultivars

Triticale, a hybrid cereal crop derived from the cross of wheat and rye, is widely used for silage production owing to its high nutritional qualities and tolerance to varying climatic conditions. The genotype and maturity stage of forage crops govern the efficiency of microbial inoculants used for ensiling. The effects of homofermentative (HMF; Lactiplantibacillus plantarum and Enterococcus faecium) and heterofermentative (HTF; Lentilactobacillus buchneri) inoculants, either alone or in combination, on the fermentation quality, nutrient composition, and in vitro rumen digestibility of ensiled triticale varieties (Alperbey and Karma 2000) were assessed in this study. The study was carried out using a 2 × 2 × 2 factorial arrangement of two triticale varieties, two levels of HMF [0 or 1 × 105 CFU/g fresh forage (0.8 mg/kg)], and two levels of HTF [0 or 0.5 × 105 CFU/g fresh forage (500 mg/kg)]. Forages were harvested at the early dough stage, vacuum-packed in 110 μm-thick plastic bags (35 cm × 25 cm), and allowed to ferment for 120 days. Fermentation characteristics, chemical composition, volatile fatty acids, and digestibility traits were evaluated after ensiling. Application of HMF inoculant significantly reduced silage pH compared to the control and HTF treatments in Alperbey, whereas in Karma 2000, terminal pH remained statistically similar between control and HMF treatments. Generally, inoculated silages had lower ammonia nitrogen levels than control silages, reflecting better protein conservation. The HTF significantly increased the acetic acid and decreased the butyric acid concentrations. There were significant two-way (variety × HMF and variety × HTF) and three-way (variety × HMF × HTF) interactions for crude protein content, fiber contents, volatile fatty acids profile, and digestibility characteristics (p < 0.05). For Karma 2000, the application of HMF increased crude protein concentration; however, it also increased lignin and fiber contents, thereby reducing organic matter digestibility. In contrast, dual inoculation raised neutral detergent fiber digestibility. The results show that variety-specific inoculant selection can improve triticale silage quality, underscoring the importance of aligning microbial additives with the forage’s biochemical properties.