Use of lemongrass oil for manipulation of ruminal fermentation using Rusitec technique

Tuesday, July 22, 2014
Exhibit Hall AB (Kansas City Convention Center)
Atitthan Nanon , Suranaree University of Technology, Muang, Thailand
Wisitiporn Suksombat , Suranaree University of Technology, Muang, Thailand
Wenzhu Yang , Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
Abstract Text:

Supplementation of lemongrass powder or meal has revealed a positive impact on ruminal fermentation in beef cattle. However, lemongrass essential oil (LMO) has little been evaluated on its effect on ruminal fermentation. A study using Rusitec technique was conducted to investigate the effect of increasing dose of LMO supplementation on fermentation characteristics of a dairy cow diet. Experiment was a completely randomized design with 4 replications in each treatment and consisted of 10 d of adaptation and 6 d of data collection. The substrate consisted of 35% grass hay, 15% alfalfa hay, 25% barley grain, 20% wheat dried distillers grains with solubles, and 5% vitamin and mineral supplement. Four treatments were: 1) control (no additives), 2) low LMO (100 mg LMO/kg DM), 3) high LMO (200 mg LMO/kg DM), and 4) monensin (30 mg/kg diet DM). Increasing LMO supplementation affected neither volatile fatty acid (VFA) concentration (averaged 26.0 mM) nor molar proportion (mol/100 mol) of acetate (49.0), propionate (23.3) or butyrate (16.2). However, increasing LMO linearly (P < 0.01) increased large peptide N from 2.6, 3.1 to 3.3 mg/mL and small peptide N from 3.3, 4.1 to 4.5 mg/mL, and linearly (P < 0.01) reduced ammonia N concentration from 8.8, 8.3 to 7.9 mg/mL in fermentation media. Increasing LMO addition also linearly (P < 0.02) increased bacterial protein production from 66.3, 66.2 to 70.1 mg/d N, and tended (P = 0.10) to improve bacterial efficiency from 12.7, 12.9 to 13.3 g N/kg digested OM. However, digestibility (% of input) of DM (52.8), NDF (41.9), starch (76.5), and CP (59.0) was not affected by increasing LMO addition. Supplementation of monensin did not affect fermentation characteristics, feed digestion, and bacterial protein production. These results suggest that supplementation of a dairy cow diet with LMO inhibited deamination process by possibly altering microbial populations such as proteolytic bacteria.

 Keywords: Fermentation, lemongrass oil, Rusitec