Skip to main content
ARS Home » Northeast Area » University Park, Pennsylvania » Pasture Systems & Watershed Management Research » Research » Publications at this Location » Publication #362220
Research Project: Multifunctional Farms and Landscapes to Enhance Ecosystem Services (Bridge Project)

Location: Pasture Systems & Watershed Management Research

Title: Ruminal fermentation and enteric methane production of legumes containing condensed tannins fed in continuous culture

Author
item ROCA-FERNANDEZ, ANA - Universidad De Chile
item DILLARD, LEANNE - Auburn University
item Soder, Kathy

Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 5/18/2019
Publication Date: 7/8/2019
Citation: Roca-Fernandez, A., Dillard, L.S., Soder, K.J. 2019. Ruminal fermentation and enteric methane production of legumes containing condensed tannins fed in continuous culture[abstract]. Journal of Animal Science. P. 1.

Interpretive Summary: Plant secondary compounds such as condensed tannins can impact ruminal fermentation in grazing cattle. We added four legumes containing various levels of condensed tannins (alfalfa- no tannins; birdsfoot trefoil- low tannins; crown vetch- moderate tannins, and sericea lespedeza- high tannins) to an orchardgrass diet in a 50:50 ratio to evaluate the effects of these legumes on ruminal fermentation and methane production in a continuous culture fermentor system. As tannin concentration of the legume increased, methane production decreased, which could be environmentally beneficial. However, at the same time, ruminal fermentation was decreased with increasing tannin concentrations, which may impair animal productivity. Further research is needed with grazing animals to verify these results.

Technical Abstract: A continuous culture fermentor study was conducted to assess nutrient digestibility, VFA concentration, microbial protein synthesis, bacterial N efficiency and enteric methane (CH4) production of 4 legumes containing different condensed tannins (CT) concentrations. Legumes were fermented in a 50:50 diet with orchardgrass (Dactylis glomerata L.): 1) Alfalfa (Medicago sativa L.; ALF no CT); 2) Birdsfoot trefoil (Lotus corniculatus L.; BFT, low CT); 3) Crown vetch [Securigera varia (L.); CV, moderate CT]; 4) Sericea lespedeza [Lespedeza cuneata (Dum. Cours.); SL, high CT]. Diets were randomly assigned to 4 fermentors in 4 periods in a 4 × 4 Latin square design, with 7 d for adaptation and 3 d for sample collection. Temperature, pH and CH4 concentrations were recorded. Effluent samples were analyzed for pH, VFA, and DM, OM, CP, NDF and ADF for determination of apparent (DM, OM, NDF and ADF) and true (DM and OM) nutrient digestibilities. Microbial protein synthesis and bacterial efficiency were estimated by analysis of N flows and purines. Forage samples were analyzed for DM, OM, CP, NDF, ADF, minerals and CT concentrations. Data were analyzed using the GLIMMIX procedure of SAS. The CT concentrations (g/kg DM) were 3, 21, 38 and 76 in ALF, BFT, CV and SL, respectively. Apparent and true DM and OM digestibilities were lower (P < 0.01) in SL than in ALF and BFT. Bacterial N efficiency per kg of truly digested DM and OM was lower (P = 0.05) in SL than in BFT and CV. The lowest (P < 0.001) CH4 production per unit of digestible nutrients was found in SL. There was a negative correlation (P < 0.001) between CT concentration and CH4 production. However, tradeoffs in ruminal fermentation (reduced nutrient digestibility, VFA concentration and bacterial N efficiency) must be considered when SL is used.