Effect of cultivar and the number of harvests on the feed value, protein fractions and nutrient digestibility of Festulolium braunii forage in young cattle

The effect of three Festulolium braunii cultivars (Felopa, Perun, and Lofa) and five successive cuts on the nutritional value of herbage and silage was evaluated. The chemical composition, carbohydrate and protein fractions, ensilability, fermentation parameters were determined. The nutrient digestibility of experimental diets containing silages made from different F. braunii cultivars was determined by the simple balance methods in 45 Holstein-Friesian bulls (three groups of 15 animals) at the end of fattening. The experiment lasted 90 days, the animals were fed a total mixed ration. Festulolium braunii cv. Lofa and third-cut and fourth-cut herbage were characterized by the most desirable chemical composition. Festulolium braunii cv. Felopa had the highest concentration of water-soluble carbohydrates (P = 0.046) and the highest buffering capacity (P = 0.005). First-cut silage had the highest content of lactic acid (P = 0.018). The protein fraction composition of silage varied across cuts, and significant differences between cultivars were found only for fraction B1 (P = 0.046), whose proportion was highest in cv. Perun. Fourth-cut silage had the lowest proportion of fraction A (P ≤ 0.01) and the highest proportion of fraction B1 (P = 0.037). The nutrient digestibility coefficients of experimental diets were influenced by the number of cuts (P ≤ 0.05) and the interaction of both factors (P ≤ 0.01). The study confirmed the high feed value of F. braunii, which provides high-quality forage for ruminants. The significant differences in the nutritional value of F. braunii herbage and silage observed among cultivars and cuts indicate that various cultivars cut multiple times at different harvest dates should be tested in future studies.