INFLUENCE OF CUTTING AGE ON CHEMICAL COMPOSITION, RUMEN DEGRADATION KINETICS AND in vitro DIGESTIBILITY OF GREEN HYDROPONIC FODDER OF Avena sativa

Abstract

<p>The aim of this research was to evaluate the influence of cutting age on chemical chemistry, rumen degradation kinetics and <em>in vitro</em> digestibility of hydroponic green forage of <em>Avena sativa</em>. 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) as the days to cut increased. The degradation of the OM fraction A was reduced linearly (P <0.05) within days at the cut. Fraction B showed no differences (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 <em>A. sativa</em>.</p>