Ensiling Techniques for Whole-Plant Sunflowers (Helianthus annuus) and their Nutritive Values for Ruminants in Vietnam

Abstract

The study aimed to evaluate the biomass yield, chemical composition and ensiling techniques of wholeplant sunflower Aguara 6. In Exp. 1, whole sunflower plant was harvested at the seeding period (SP) to measure biomass yield, chemical composition and energy values. Results showed that, fresh biomass yield was 62 tonnes/ha, in which, heads consisting of 46.8% with the highest, leave accounting for 35.5% and stems consisting of 17.7% as fresh matter with the lowest proportion. The dry matter (DM) content of the whole plant was 17.5% DM, in which 13.5% CP, 45.8% NDF, 44% ADF and 20.7% Lignin; and DE and ME values for ruminants were 3,436 and 2,818 kcal/kg DM, respectively. In Exp. 2, eight treatments included: Control (CTL) -without any additives; Salt 0.5% added to CTL (SCTL); Cassava byproduct added to CTL at 5, 10 and 15% (CB5, CB10 and CB15, respectively); Molasses added to CTL at 2.5, 5.0 and 7.5% (M2.5, M5.0 and M7.5, respectively). Samples were collected at day 0, 7, 14 and 21 for pH and ammonia, and day 0 and 21 for chemical analysis. Results indicated that after 21 days of ensiling, the pH value of silage in 8 treatments were lower than 4.5. There was no effect of additives and their level inclusions on ensiled sunflowers nutritive values. Change in organic matter was found with 0.7-2.3% unit in all treatments. In general, whole Aguara 6 sunflower can be ensiled and has a potential for ruminants.