Effect of sunflower oil (Helianthus annuus) in ruminal fermentation in vitro and emission of gases

Abstract

Objective: The production of total gas, methane (CH₄) and in vitro fermentative variables in diets for sheep with 1 and 2 % sunflower oil were evaluated. Design/Methodology/Approach: Serological vials with 0.5 g of treatment and 50 ml of culture medium were incubated at 39 °C for 24, 48 and 72 h. The production of total gas, CH₄, and degradation of dry matter (DEGDM), neutral detergent fiber (DEGNDF), acid (DEGADF), production of volatile fatty acids (VFA) and ammoniacal nitrogen (N-NH3) were estimated. . The experimental design was completely randomized. Results: Total gas production at 48 and 72 h increased (p < 0.05) and at 24 h decreased (p < 0.05) as the oil increased. CH4 production at 24 and 48 h did not present differences (p > 0.05); a linear decrease (p < 0.05) was quantified at 72 h. DEGDM increased (p < 0.05) at 24 and 48 h and decreased (p < 0.05) at 72 h. DEGNDF and DEGADF increased (p < 0.05) at 48 h. Butyric acid content and N-NH₃ decreased (p < 0.05) at 48 h. Study Limitation/Implications: An inclusion greater than 2 % of sunflower oil in the diet can reduce the degradability of the food and the microbial protein. Findings/Conclusions: The inclusion of up to 2% of sunflower oil in diets for lambs does not affect the degradation of fibers and is an alternative to reduce the methane emitted into the environment.