evaluation of extracts for ruminants

• Main Authors: Do Hyung Kim, Shin Ja Lee, Da Som Oh, Il Dong Lee, Jun Sik Eom, Ha Young Park, Seong Ho Choi, Sung Sill Lee
• Format: Article
• Language: English
• Published: Asian-Australasian Association of Animal Production Societies 2018-10-01
• Series: Asian-Australasian Journal of Animal Sciences
• Subjects: Extracts; Ruminal Fermentation; Microbial Growth
• Online Access: http://www.ajas.info/upload/pdf/ajas-31-10-1635.pdf

Objective This study was conducted to evaluate the effects of Rhus succedanea extract addition on in vitro ruminal fermentation and microbial growth. Methods Two ruminally-fistulated steers consuming 600 g/kg timothy- and 400 g/kg cracked corn-based concentrate with free access to water and mineral block were used as rumen fluid donors. In vitro batch fermentation, with timothy as a substrate, was conducted for up to 72 h, with Rhus succedanea extracts added to achieve final concentrations of 0, 10, 30, 50, 70, and 90 mg/L. Results Effective dry matter (DM) degradability rate linearly decreased (p = 0.046) depending on extract dosing levels. Total gas production after 24 to 72 h incubation tended to decrease following extract addition, beginning with 50 mg/L starting dose (significance of quadratic effects: p = 0.006, p<0.001, and p = 0.008 for 24, 48, and 72 h, respectively). Methane production decreased depending on dosing levels following 24 h (p<0.05) and 48 h (p<0.005) incubations and was the lowest with the 50 mg/L dose. The Rhus succedanea extracts increased the abundance of Fibrobacter succinogenes (p<0.05) and Ruminococcus flavefaciens (p = 0.0597) and decreased the abundance of methanogenic archaea (p<0.05) following 24 h incubation. Conclusion Rhus succedanea was shown to reduce methane production and increase cellulolytic bacteria without any signs of toxic effects and with a minor effect on DM degradability.