Tropical and Subtropical Agroecosystems (Nov 2019)
INFLUENCE OF CUTTING AGE ON CHEMICAL COMPOSITION, RUMEN DEGRADATION KINETICS AND in vitro DIGESTIBILITY OF GREEN HYDROPONIC FODDER OF Avena sativa
Abstract
The aim of this research was to evaluate the influence of cutting age on chemical chemistry, rumen degradation kinetics and in vitro digestibility of hydroponic green forage of Avena sativa. The treatments were: T1: 8 days, T2: 11 days, T3: 14 days and T4: 17 days after germination. The DM showed a linear increase (P = 0.0034) at the harvest days. The NDF was higher in treatments T3 and T4 (457.2 and 479.1 g/kg DM respectively). The OM, AFD, GE and the digestibility of the DM and OM showed no differences (P> 0.05) between treatments. The ruminal degradation of DM fractions A, B and A + B showed no differences (P> 0.05). The degradation rate (c% h1) was higher in T2. The effective degradation showed a linear reduction (P 0.05) between treatments and the degradation rate (c% h1) was higher (P = 0.0009) in T2. The effective degradation decreased linearly (P = 0.0001) as the days to cut increased. The CP fraction A was higher (P = 0.0001) in T3 (888.0 g / kg DM). Fraction B and degradation rate (c% h1) was higher in T1 and T4. The effective degradation (0.02% k) showed no differences (P> 0.05), at 0.05% k it was higher in T1, T2 and T3. And at 0.08% k was higher in T2 and T3. The degradation of the FDN fraction A was higher in T1, T3 and T4. Fraction B and A + B showed no differences (P> 0.05) between treatments. The degradation rate (c% h1) was higher in T1 and T2. And the effective degradation showed no differences (P> 0.05) between treatments. It´s concluded that the optimum harvest time to achieve a better chemical composition and greater ruminal digestion is between the 11 days of harvest of the hydroponic green forage of A. sativa.
