Location: Meats Safety & Quality ResearchTitle: Methane emissions by goats consuming Sericea lespedeza at different feeding frequencies Author
|Wells, James - Jim|
Submitted to: Animal Feed Science And Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/17/2012
Publication Date: 6/20/2012
Citation: Puchala, R., Animut, G., Patra, A.K., Detweiler, G.D., Wells, J., Varel, V.H., Sahlu, T., Goetsch, A.L. 2012. Methane emissions by goats consuming Sericea lespedeza at different feeding frequencies. Animal Feed Science And Technology. 175:76-84. Interpretive Summary: Tannin containing forages can reduce methane production from the rumen, but animal productivity can suffer. This study was conducted to determine if infrequent feeding of tannin-containing forage would sustain low methane production. Animals were fed tannin-containing forages at frequencies of every day, every other day, every fourth day or every eighth day with alfalfa hay offered on the other days. Results indicated that feeding the legume containing the high level of tannins reduced methane production consistently on days fed and resulted in lower levels of methane production for up to 5 days from day of feeding. It is concluded that feeding hays containing high levels of tannins can reduce methane emission (greenhouse gas) from ruminant animals and lower rates of methane production can carry over for several days after initial feeding. Producers could implement phase feeding every fourth day with better forages to sustain meat animal production and minimize greenhouse gas emissions.
Technical Abstract: Twenty-four yearling Boer (50 or 87.5%) × Spanish wethers were used to assess effects of different sources of fresh forage and dry hay on ruminal methane emission. Treatments were a legume (Sericea lespedeza, Lespedeza cuneata) high in condensed tannins (CT; 20 and 15% in fresh forage and hay, respectively) without (SER) or with polyethylene glycol (25 g/d; SER-PEG), a legume low in CT (alfalfa, Medicago sativa; ALF), and a grass low in CT (sorghum-sudangrass, Sorghum bicolor; GRASS). Experiments were 22 d, with the first 16 for adaptation. Intake of OM was 867, 823, 694, and 691 g/d (SE = 20.1) with fresh forage and 802, 886, 680, and 604 g/d with hay for SER, SER-PEG, ALF, and GRASS, respectively; SE = 51.3). Apparent total tract N digestion was greater for SER-PEG vs. SER (P < 0.05) with fresh forage (46.3, 66.5, 81.7, and 73.2%; SE = 1.71) and hay (44.2, 68.4, 59.7, and 48.6% for SER, SER-PEG, ALF, and GRASS, respectively; SE = 2.08). Intake of ME was similar among treatments with fresh forage (8.24, 8.06, 7.42, and 7.70 MJ/d; SE = 0.434), and with hay was greatest (P < 0.05) for SER-PEG (6.88, 8.63, 6.45, and 5.34 MJ/d for SER, SER-PEG, ALF, and GRASS, respectively; SE = 0.659). The number of ciliate protozoa in ruminal fluid was lowest for SER (P < 0.05) with fresh forage (9.8, 20.1, 21.0, and 33.6 × 105/ml; SE = 2.76) and hay (6.3, 11.4, 13.6, and 12.5 × 105/ml for SER, SER-PEG, ALF, and GRASS, respectively; SE = 1.43). Methane emission in g/d was lower (P < 0.05) for SER vs. ALF and GRASS with fresh forage (10.1, 12.7, 13.7, and 13.8; SE = 0.90) and hay (10.2, 13.9, 14.1, and 12.8 for SER, SER-PEG, ALF, and GRASS, respectively; SE = 0.76). Primarily because of differences in methane emission, ME as a percentage of DE was greatest (P < 0.05) for SER with fresh forage (87.2, 85.3, 81.1, and 82.7; SE = 0.97) and for SER and SER-PEG with hay (89.5, 89.1, 85.6, and 86.4 for SER, SER-PEG, ALF, and GRASS, respectively; SE = 0.94). In summary, methane emission was similar between a legume and grass low in CT as fresh forage and hay. The CT in SER markedly decreased N digestion and elicited a moderate decline in ruminal methane emission. Supplementation with PEG alleviated the effect of CT on N digestibility but not ruminal methane emission presumably because of different modes of action. In conclusion, forage CT deserve further study as a potential means of decreasing ruminal methane emission.