Effects of 5-Aminolevulinic Acid Supplementation on Gas Production, Fermentation Characteristics, and Bacterial Community Profiles In Vitro

Abstract

To investigate the effect of 5-aminolevulinic acid (5-ALA) on in vitro rumen gas production, fermentation characteristics, and bacterial community profiles, five levels of 5-ALA (0, 100, 500, 1000, and 5000 mg/kg DM) were supplemented into a total mixed ration (concentrate/forage = 40:60) as substrate in an in vitro experiment. Results showed that as the supplementation level of 5-ALA increased, asymptotic gas production (b) decreased linearly and quadratically (p p p = 0.03) and pH value increased linearly and quadratically (p 3-N and the ratio of acetate/propionate (A/P) decreased linearly and quadratically (p p p Actinobacteriota was positively correlated with the gas production parameter b, the ratio of A/P, and the concentration of butyrate, isovalerate, and NH3-N (p p WPS-2 exhibited a negative correlation with the gas production parameter b, the ratio of A/P, and the concentration of butyrate, valerate, isobutyrate, isovalerate, and NH3-N (p p = 0.04). The Bacteroidales BS11 gut group was negatively correlated with the concentration of propionate but positively correlated with gas production parameter b and the concentration of butyrate and NH3-N (p Lachnospiraceae NK3A20 group was found to have a positive correlation with gas production parameter b, the ratio of A/P, and the concentration of butyrate, isobutyrate, isovalerate, valerate, total VFA, and NH3-N (p p Actinobacteriota, the Bacteroidales BS11 gut group, the Lachnospiraceae NK3A20 group, and certain pathogenic bacteria and increasing the abundance of WPS-2.

Keywords

• 5-ALA
• beef cattle
• in vitro rumen fermentation
• bacterial diversity