Seung Kyu Ahn

Changes in Microbial Diversity, Methanogenesis and Fermentation Characteristics in the Rumen in Response to Medicinal Plant Extracts

This study evaluated the in vitro effect of medicinal plant extracts on ruminal methanogenesis, four different groups of methanogens and ruminal fermentation characteristics. A fistulated Holstein cow was used as a donor of rumen fluid. Licorice and mugwort extracts (Glycyrrhiza uralensis and Artemisia capillaris, 0.5% and 1% of total substrate DM, respectively), previously used as folk remedies, were added to an in vitro fermentation incubated with buffered-rumen fluid. Total gas production in Glycyrrhiza uralensis extract treatment was not significantly different between treatments (p<0.05) while total gas production in the Artemisia capillaris extract treatment was lower than that of the control. Artemisia capillaris extract and Glycyrrhiza uralensis extract reduced CH4 emission by 14% (p<0.05) and 8% (p<0.05), respectively. Ciliate-associated methanogens population decreased by 18% in the medicinal plant extracts treatments. Medicinal plant extracts also affected the order Methanobacteriales community. Methanobacteriales diversity decreased by 35% in the Glycyrrhiza uralensis extract treatment and 30% in the Artemisia capillaris extract treatment. The order Methanomicrobiales population decreased by 50% in the 0.5% of Glycyrrhiza uralensis extract treatment. These findings demonstrate that medicinal plant extracts have the potential to inhibit in vitro ruminal methanogenesis.

Physicochemical characteristics and fatty acid profiles of muscle tissues from Hanwoo steers fed a total mixed ration supplied with medicinal plant by-products

Objective Using medicinal plant by-products (MPBP) as feed additives may be an eco-friendly option as substitutes for feedstuffs and may assist in reducing the improper disposal of MPBP. Therefore, this study was conducted to evaluate the influences of MPBP on the meat quality of Hanwoo steers fed a total mixed ration (TMR). Methods Twenty seven steers (body weight = 573±57 kg) were randomly divided into three treatments with a control group and two tested groups as follows: control, 1,000 g/kg TMR; treatment 1 (MPBP30), 970 g/kg TMR and 30 g/kg MPBP; treatment 2 (MPBP50), 950 g/kg TMR and 50 g/kg MPBP. Results Average daily gain, feed conversion ratio and the Commission Internationale de l’Eclairage L* of muscle were improved (p<0.05, respectively) by MPBP30. Stearic acid (C18:0) was decreased (linear effect, p = 0.012), while oleic acid (C18:1) was increased (linear effect, p = 0.055) by MPBP level. Saturated fatty acid (SFA) and polyunsaturated fatty acid (PUFA) were decreased for MPBP50 while unsaturated fatty acid (USFA) and monounsaturated fatty acid (MUFA) were increased for MPBP 50. USFA and SFA ratio was increased for MPBP50 as well. Conclusion These results indicated that MPBP supplementation in Hanwoo steers fed a TMR increased feed efficiency and meat color (lightness) with altering fatty acid proportions. Therefore, MPBP may be successfully used in ruminant feeding.