Effects of lespedeza condensed tannins alone or with monensin, soybean oil, and coconut oil on feed intake, growth, digestion, ruminal methane emission, and heat energy by yearling Alpine doelings

Authors: LIU, H - Langston University; PUCHALA, R - Langston University; LESHURE, S - Langston University; GIPSON, T - Langston University; Flythe, Michael; GOETSCH, A - Langston University

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/25/2018
Publication Date: 11/27/2018
Citation: Liu, H., Puchala, R., Leshure, S., Gipson, T.A., Flythe, M.D., Goetsch, A.L. 2018. Effects of lespedeza condensed tannins alone or with monensin, soybean oil, and coconut oil on feed intake, growth, digestion, ruminal methane emission, and heat energy by yearling Alpine doelings. Journal of Animal Science. 97(2):885-899. https://doi.org/10.1093/jas/sky452.
DOI: https://doi.org/10.1093/jas/sky452

Interpretive Summary: The objective of the experiment was to evaluate effects of the condensed tannin-rich forage, Sericea lespedeza , on methane emission by Alpine dairy goats. The methane is made my microorganisms in the rumen of the goat. There are various means to decrease methane emission by ruminant livestock. Some antimicrobial additives such as ionophores (e.g. monensin) can decrease methanogenesis in the rumen. In some cases, consumer pressure has caused shifts from such substances towards 'natural' alternatives. In this study, the combined effects of dietary Sericea lespedeza with an ionophore and coconut or soybean oil were evaluated. All of the treatments decreased methane from the goats compared to goats receiving only the control diet (alfalfa hay), but there was no advantage to including the other additives to Sericea lespedeza. In some previous experiments, the rumen microorganisms responded to methane suppression by adapting and returning to unsuppressed levels of methane production. However, in this experiment methane production remained suppressed. Importantly, Sericea lespedeza did not reduce the number of bacteria that break down fiber or otherwise interfere with digestion in the rumen. This research suggests the Sericea lespedeza condensed tannins can be used to decrease methane production from dairy goats.

Technical Abstract: Fifty-four Alpine doelings (initial BW and age of 31.7 ± 0.38 kg and 306 ± 1.9 d, respectively) were allocated to nine treatments with ad libitum intake of 25% concentrate and 75% forage diets. Alfalfa was the forage in the control diet (C) and others consisted of Sericea lespedeza with 1.25% DM of quebracho extract in concentrate, for a condensed tannin (CT) level of 8.4%. Lespedeza treatments were no additive (L) and inclusion of monensin (I) at 22 mg/kg DM (L-I), soybean oil (SBO) at 3% DM (L-S), coconut oil (CCO) at 3% DM (L-N), I and 3% DM SBO (L-I-S), I and 3% DM CCO (L-I-N), 1.5% DM SBO and 1.5% DM CCO (L-S-N), and I, 1.5% DM SBO, and 1.5% DM CCO (L-I-S-N). The experiment was 12 wk with two 6-wk periods, gas exchange determined in wk 6, and 12, and other measures in wk 5 and 11. The C diet averaged 2.67% N, 43.8% NDF, and 8.8% ADL, and the L diet was 2.03% N, 42.8% NDF, and 13.2% ADL. Intake of DM was 1.46, 1.23, 1.30, 1.18, 1.32, 1.10, 1.02, 1.20, and 1.01 kg/d (SEM = 0.059), ADG was 124, 80, 89, 84, 101, 77, 74, 78, and 62 g (SEM = 9.6), and eating time was 183, 238, 240, 195, 216, 198, 219, 187, and 209 min/d for C, L, L-I, L-S, L-N, L-I-N, L-S-N, and L-I-S-N, respectively (SEM = 19.9). There were no treatment × period interactions (P > 0.05) in digestibilities or methane emission. Total tract digestibilities of OM (57.4, 50.9, 51.8, 52.7, 50.3, 52.1, 52.1, 51.9, and 49.8%; SEM = 1.42) and N (59.1, 31.2, 32.5, 37.1, 31.6, 38.3, 30.4, 38.4, and 34.1% for C, L, L-I, L-S, L-N, L-I-N, L-S-N, and L-I-S-N, respectively; SEM = 2.21) were greater for C than for lespedeza treatments (P < 0.05). Ruminal methane emission was lower for diets with lespedeza than for C in MJ/d (1.36, 0.76, 0.84, 0.71, 0.71, 0.66, 0.65, 0.68, and 0.68; SEM = 0.048) and relative to gross energy intake (5.92, 3.27, 3.49, 3.19, 2.84, 2.91, 3.20, 3.20, and 3.27%; SEM = 0.165), and DE (11.19, 6.98, 7.40, 6.38, 5.90, 5.69, 6.37, 6.38, and 6.70% for C, L, L-I, L-S, L-N, L-I-N, L-S-N, and L-I-S-N, respectively; SEM = 0.400). In conclusion, the magnitude of effect of condensed tannins mainly of lespedeza on ruminal methane emission by Alpine doelings did not diminish over time and was not markedly influenced by dietary inclusion of monensin, soybean oil, or coconut oil.