Hydroponically Sprouted Grains: Effects on In Situ Ruminal Nutrient Degradation, Fractional Disappearance Rate, and Effective Ruminal Degradation

This study aimed to evaluate in situ ruminal nutrient degradation, fractional disappearance rate, and effective ruminal degradation of hydroponically sprouted barley, wheat, and triticale. Two ruminally canulated lactating cows were used in a complete randomized block design with four treatments and nine incubation times (0, 2, 4, 8, 12, 24, 48, 72, and 240 h). Treatments were corn silage (control), and sprouted barley, triticale, and wheat. Quadruplicate samples (5 g each) were placed in Dacron bags and incubated in the rumen. Then, bags were rinsed and spun, dried (48 h × 55 °C; 3 h × 105 °C), and weighed to determine residual dry matter (DM). Data were analyzed using mixed models (MIXED, SAS 9.4) with treatment, time, and their interaction as fixed effects, and cow and replicate (cow) as random effects. Denominator degrees of freedom were adjusted using the Kenward–Roger method, and means were separated by Tukey–Kramer. Significance was declared at p ≤ 0.05 and tendencies at 0.05 < p ≤ 0.10. Sprouted triticale and wheat treatments had a greater rapidly soluble fraction for DM (p < 0.01), the greatest fractional disappearance rate for DM (p < 0.01) and neutral detergent fiber (NDF; p < 0.01), and greater effective ruminal degradability (ERD) for DM (p < 0.01) and crude protein (CP; p < 0.01). Sprouted wheat also had the greatest ERD for NDF (p < 0.01). In contrast, sprouted barley had the lowest rapidly soluble fractions for DM (p < 0.01), NDF (p < 0.01), and CP (p < 0.01), lower fractional disappearance rate for DM (p < 0.01) and NDF (p < 0.01) than sprouted triticale and wheat, and the lowest ERD for DM (p < 0.01) and CP (p < 0.01). Overall, sprouted triticale and wheat had greater in situ ruminal nutrient degradation, effective ruminal degradation, and nutrient degradation kinetics, indicating their potential for inclusion in dairy cattle diets to improve nutrient degradability.