PSXII-27 Effects of Sericea lespedeza on methane emission and health status in grazing Boer goat wethers

The objective was to determine effects of feeding 12 yearling Boer goat wethers Sericea lespedeza as supplemental pellets or grazed forage on ruminal methane emission and health status compared with grazing grass-based pasture and supplemental forage-concentrate pellets. There were 4 5-wk periods in the late spring and summer. Periods 1–3 were on a 0.7-ha native grass pasture and period 4 was on a 1.1-ha pasture of Sericea lespedeza. A forage-concentrate pellet was supplemented in period 1 (CON1), 3 (CON2), and 4 (SL-P), and pelleted Sericea lespedeza (Sims Brothers Inc., Union Springs, AL) was given in period 2 (SL-S). Pellets were supplemented and ruminal methane emission was measured with a small ruminant GreenFeed unit (C-Lock, Rapid City, SD). Pellets were dispensed up to 30 times daily, with 6 sessions of 5-9-g bait drops and a 2.5-h session interval. Body weight at the end of periods generally increased as period advanced (35.7, 38.8, 37.9 and 41.1 kg for CON1, SL-S, CON2, and SL-P, respectively; SEM=1.08). Sericea lespedeza decreased methane emission (P < 0.05), with pasture grazing having greater effect than pellet supplementation (43.7, 36.2, 40.9, and 32.5 g/d for CON1, SL-S, CON2, and SL-P, respectively; SEM=0.84). Likewise, SL consumption decreased FAMACHA score (P < 0.05), with a similar effect for both SL forms (3.28, 2.95, 3.21, and 2.86 for CON1, SL-S, CON2, and SL-P, respectively; SEM=0.061). Body condition score was similar among periods (2.65, 2.64, 2.68, and 2.67 for CON1, SL-S, CON2, and SL-P, respectively; SEM=0.022). In conclusion, the effect of consumption of SL on methane emission probably relates to condensed tannins and greater impact of SL-P could involve a higher dietary level. Similarly, inclusion of SL in meat goat diets has potential to decrease the parasite load and thereby improve health status, also presumably because of bioactive condensed tannins.

High-Condensed Tannin Diet and Transportation Stress in Goats: Effects on Physiological Responses, Gut Microbial Counts and Meat Quality

Feeding condensed tannin (CT)-containing diets such as sericea lespedeza (Lespedeza cuneata) and reducing stress have been reported to improve meat quality and food safety in goats. In a completely randomized design with split-plot, thirty-six uncastrated male Spanish goats were assigned to 3 dietary treatments (n = 12/treatment): ground ‘Serala’ sericea lespedeza hay (SER), bermudagrass (Cynodon dactylon) hay (BG), or bermudagrass hay—dewormed goats (BG-DW; Control) at 75% of intake, with a corn-based supplementation (25%) for 8 weeks. Prior to slaughter, goats were either transported for 90 min to impose stress or held in pens. Basophil counts were lower (p < 0.01) in the SER group compared to BG or BG-DW groups suggesting a better anti-inflammatory capacity due to polyphenols in the SER diet. Compared to BG-DW group, cortisol level was higher (p < 0.05) and norepinephrine was lower (p < 0.05) in the SER group. The SER group had the lowest aerobic plate counts (APC) in both rumen and rectum (p < 0.01). Longissimus dorsi muscle initial pH was not affected by diet or stress. Feeding sericea hay to goats may have beneficial effects, such as enhanced antioxidant and anti-inflammatory properties during stress and reduced gut microbial counts, without changing meat quality characteristics.

Methane emissions and δ 13C composition from beef steers consuming increasing proportions of sericea lespedeza hay on bermudagrass hay diets

An experiment was conducted to evaluate the effects of different proportions of ‘Au Grazer’ sericea lespedeza [SL, Lespedeza cuneata (Dum. Cours.) G. Don], a legume rich in condensed tannins (CT), on nutrient intake and digestibility, and to estimate methane (CH4) emissions and 13C isotopic composition (δ 13CCH4) from beef steers consuming a forage-based diet. Twenty-five Angus-crossbred steers were distributed in a randomized complete block design (344 ± 48 kg initial BW), and randomly assigned to one of five treatments: 0SL, 25SL, 50SL, 75SL, and 100SL, diets containing 0, 25, 50, 75 and 100% of SL hay, respectively, mixed with ‘Tifton-85’ bermudagrass hay (Cynodon spp.). The study was carried out for two experimental periods of 21-d each. The statistical model included the fixed effect of treatment and random effects of block, experimental period, and their interaction. Apparent total tract digestibility of crude protein, neutral detergent fiber, and acid detergent fiber were linearly decreased (P &lt; 0.001) by the inclusion of SL. No effects were observed for total CH4 emissions per day, nor for CH4 relative to organic matter intake or digestible organic matter with the inclusion of SL. However, emission of CH4 in relation to intake of CT was affected by treatment (P &lt; 0.001). A linear (P &lt; 0.001) decrease and a quadratic effect (P &lt; 0.001) were observed for δ 13C of diets and gas, respectively, in which diets and enteric CH4 with greater inclusion of SL were more depleted in 13C. Moreover, the difference in δ 13C between diets and gas (Δδ 13C) had a linear decrease (P = 0.001) with the inclusion of SL. The model developed to predict the C3 proportions in the enteric CH4 fitted to predicted values (P &lt; 0.0001). Therefore, greater proportions of SL resulted in lesser CH4 emission when CT intake was considered and the isotopic composition from enteric CH4 was able to predict the contribution of SL in the emissions.

Plasma metabolomic profiles as affected by diet and stress in Spanish goats

The effects of high-condensed tannin (CT) diet combined with preslaughter stress have not been studied at the metabolome level in goats. This study was conducted to determine the effects of feeding sericea lespedeza (SL; Lespedeza cuneata), a high-CT legume, and transportation stress on plasma metabolome in goats. Uncastrated male Spanish goats (age = 8 months; BW = 26.0 ± 0.48 kg) were either fed ground ‘Serala’ SL hay (SER), bermudagrass (Cynodon dactylon) hay (BG), or bermudagrass hay-dewormed goats (BG-DW; Control) at 75% of intake, with a corn-based supplementation (25%) for 8 weeks (n = 12/Diet). At the end of the trial, goats were subjected to one of two stress treatments (ST): transported for 90 min to impose stress (TS) or held in pens (NTS) before slaughtering, in two replicates. Live and carcass weights, and blood samples were collected at 0, 30, 60 and 90 min of transportation or holding time (Time). The data were analyzed using MIXED procedures in SAS and metabolomics data were analyzed using the R software. When measured after ST, SER group had the lowest body weight (P < 0.05) among the three diet groups. Carcass weights were high in the BG-DW, low in SER, and intermediate in BG group. Plasma creatine concentrations decreased over Time (P < 0.01) in the TS goats in all diet groups. Meat crude protein percentages were higher (P < 0.05) in SER (22.5 ± 0.22) and BG-DW (22.3 ± 0.22) groups compared to the BG group (21.6 ± 0.22). At the metabolome level, SER group had the lowest (P < 0.05) glycine, alanine, threonine, taurine, trans-hydroxyproline, methionine, and histidine concentrations and highest (P < 0.01) lysine and citrulline concentrations among the Diet groups. Butyric acid, concentration was higher (P < 0.05) in the SER group compared to BG group. Eight medium- and long-chained acylcarnitines were higher (P < 0.05) in the BG-DW group than SER or BG groups. In general, amino acid levels decreased and acylcarnitine increased with Time (P < 0.05) in all groups. Sericea diet can be beneficial in enhancing stress coping abilities in goats due to elevated butyrate, lysine, and citrulline levels; however, SER resulted in lower energy level in goats compared to BG or BG-DW groups. Fatty acid metabolism is the main energy pathway in all groups during prolonged stress. Inclusion of certain varieties of SL in the diet must be carefully controlled to prevent possible negative effect.

Effects of prescribed fire timing on grazing performance of yearling beef cattle, forage biomass accumulation, and plant community characteristics on native tallgrass prairie in the Kansas Flint Hills

Recent research demonstrated that mid- or late-summer prescribed fires can be employed to manage sericea lespedeza (Lespedeza cuneata) infestations in the Kansas Flint Hills. The effects of prescribed fire applied during the growing season (i.e., August to October) on grazing performance of yearling cattle have not been evaluated. Native pastures (n = 18; 22 ± 4.0 ha) were grouped by watershed and assigned randomly to 1 of 3 prescribed-fire treatments: spring (7 April ± 2.1 d), summer (21 August ± 5.7 d), or autumn (2 October ± 9.9 d). Yearling beef cattle were grazed from May to August at a targeted stocking density of 280 kg live-weight ˖ ha -1 following prescribed fire application. Forage biomass accumulations, soil cover, plant species composition, and root carbohydrate concentrations in four native plant species were evaluated. Total BW gains and ADG were greater (P = 0.01) for cattle that grazed the spring and summer prescribed-fire treatments compared with those that grazed the autumn prescribed-fire treatment. As a result, final BW were greater (P = 0.04) in the spring and summer treatments than the autumn treatment. Conversely, forage biomass accumulations did not differ (P = 0.91) between fire regimes. Proportions of bare soil were greater (P &lt; 0.01) in the spring treatment compared with the summer and autumn treatments, whereas proportions of litter on the soil surface were greater (P &lt; 0.01) in summer- and autumn-burned pastures compared with spring-burned pastures. Total basal cover of graminoids and forbs did not differ (P ≤ 0.15) between prescribed fire treatments. Likewise, total basal cover of C3 or C4 perennial grasses did not differ (P ≥ 0.23) between prescribed fire treatments. No treatment differences (P = 0.24) in root starch or root water-soluble carbohydrate concentrations in big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium), Indiangrass (Sorghastrum nutans), or purple prairieclover (Dalea purpurea) were detected. These data were interpreted to suggest that summer or autumn prescribed fire can be applied without reducing forage biomass accumulations, root carbohydrate concentrations in key native plant species, or considerably altering native plant populations compared with conventional spring-season prescribed fire; however, summer prescribed fire could be favored over spring or autumn prescribed fire to both maintain stocker cattle growth performance and to achieve control over sericea lespedeza.

Effects of prescribed fire timing on vigor of the invasive forb sericea lespedeza (Lespedeza cuneata), total forage biomass accumulation, plant-community composition, and native fauna on tallgrass prairie in the Kansas Flint Hills

The predominant grazing management practice of the Kansas Flint Hills involves annual prescribed burning in March or April with post-fire grazing by yearling beef cattle at a high stocking density from April to August. There has been a dramatic increase in sericea lespedeza (Lespedeza cuneata [Dumont] G. Don) coincident with this temporally-focused use of prescribed fire in the Flint Hills region. The species is an aggressive invader and a statewide noxious weed in Kansas. Control has generally been attempted using repeated herbicide applications. This approach has not limited proliferation of sericea lespedeza and resulted in collateral damage to non-target flora and fauna. Alternative timing of prescribed fire has not been evaluated for its control. Our objectives for this 4-yr experiment were to (1) document the effects of prescribed burning during early April, early August, or early September on vigor of sericea lespedeza, standing forage biomass, and basal cover of native graminoids, forbs, and shrubs and (2) measure responses to fire regimes by grassland bird and butterfly communities. Whole-plant dry mass, basal cover, and seed production of sericea lespedeza were markedly less (P &lt; 0.01) in areas treated with prescribed fire in August or September compared with April. Forage biomass did not differ (P ≥ 0.43) among treatments when measured during July; moreover, frequencies of bare soil, litter, and total basal plant cover were not different (P ≥ 0.29) among treatments. Combined basal covers of C4 grasses, C3 grasses, annual grasses, forbs, and shrubs also did not differ (P ≥ 0.11) between treatments. Densities of grasshopper sparrow (Ammodramus savannarum), dickcissel (Spiza americana), and eastern meadowlark (Sturnella magna) were not negatively affected (P &gt; 0.10) by mid-summer or late-summer fires relative to early-spring fires. There were no differences (P &gt; 0.10) in densities of grassland-specialist butterfly species across fire regimes. Under the conditions of our experiment, prescribed burning during summer produced no detrimental effects on forage production, desirable non-target plant species, grassland birds, or butterfly communities but had strong suppressive effects on sericea lespedeza. Additional research is warranted to investigate how to best incorporate late-summer prescribed fire into common grazing-management practices in the Kansas Flint Hills.

Effects of Dietary Inclusion of Sericea Lespedeza Hay on Behavior, Heat Energy, and Ruminal Methane Emission by Growing Alpine Doelings and Katahdin Ewe Lambs

Twenty-four Alpine doelings (initial body weight (BW) and age of 25.3±0.55 kg and 10.4±0.11 mo, respectively) and 24 Katahdin ewe lambs (28.3±1.02 kg and 9.6±0.04 mo, respectively) were used to determine effects of dietary level of Sericea lespedeza (Lespedeza cuneata; 10% condensed tannins) on heat energy and ruminal emission of the greenhouse gas methane determined with an open-circuit calorimetry system. Pens with Calan feeding gates were used in the study with four 6–7-wk periods. Diets (i.e., treatments) consumed ad libitum were 75% ground hay, alfalfa, a 1:1 mixture of alfalfa and lespedeza (AL), and lespedeza. Data were analyzed with a 2 x 3 factorial arrangement of treatments, repeated measure of period, and a mixed effects model. Feeders were open 195 and 205 min/d for Alpine and Katahdin (SEM=9.8) and longer (P &lt; 0.05) for diets with lespedeza (159, 209, and 231 min/d for alfalfa, AL, and lespedeza, respectively). Rate of dry matter intake (DMI) was greater (P &lt; 0.05) for Katahdin vs. Alpine (10.2 and 6.1 g/min) and for alfalfa than for AL and lespedeza (11.1, 8.1, and 6.7 g/min, respectively). Heat energy was greater (P &lt; 0.05) in MJ/d for Katahdin than for Alpine (10.19 vs. 7.90) and similar among diets (9.20, 9.40, and 8.53; SEM=0.266), but values in kJ/kg BW0.75 were similar between animal types (560 and 579; SEM=8.4) and greatest (P &lt; 0.05) among diets for AL (563, 592, and 553 for alfalfa, AL, and lespedeza, respectively). Ruminal methane emission differed (P &lt; 0.05) between animal types in MJ/d (1.17 and 1.44), kJ/g DMI (1.39 and 1.23), and kJ/g average daily gain (ADG; 18.1 and 9.8 for Alpine and Katahdin, respectively). Regardless of period, diet did not impact methane emission in MJ/d or relative to DMI, BW, or ADG. In conclusion, it is unclear why dietary inclusion of lespedeza did not reduce ruminal methane emission as in previous studies. Species differences in methane relative to DMI and ADG (i.e., lower for sheep than for goats) deserve further attention.

Effects of Sericea Lespedeza on Feed Intake, Digestion, and Ruminal Methane Emission in Hair Sheep

Eighteen Katahdin (initial body weight of 74 kg; SEM=1.8) and 18 St. Croix ewes (55 kg; SEM=1.3) were used in an experiment with four 6-wk periods to determine effects of dietary level of Sericea lespedeza (Lespedeza cuneata) containing 5.8% condensed tannins (dry matter; DM) and other supplemental ingredients on feed intake, digestion, and ruminal methane emission. Diets were consumed ad libitum and included a concentrate supplement at 0.45% BW (DM). Alfalfa was the basal forage for control (CON), ionophore (ION; lasalocid at 33 mg/kg DM), coconut oil (3%; CCO), and soybean oil (3%; SBO) diets, and forage in moderate- and high-lespedeza diets was a 1:1 mixture of alfalfa and lespedeza and all lespedeza, respectively (MSL and HSL, respectively). Data were analyzed with a 2 x 6 factorial arrangement of treatments, period as a repeated measure, and a mixed effects model. Digestion and methane emission were determined in weeks 4, 10, 16, and 22. Total DM intake was similar among treatments (P = 0.070) but numerically greatest for HSL (1,197, 1,297, 1,491, 1,203, 1,195, and 1,207 g/d; SEM=81.1), OM digestibility ranked (P &lt; 0.05) CON, ION, CCO, and SBO &gt; MSL &gt; HSL (69.2, 57.6, 50.3, 66.3, 66.0, and 68.7%; SEM=1.57), and digestible OM intake was similar among treatments (P = 0.517; 697, 607, 589, 598, 635, and 690 g/d for CON, MSL, HSL, ION, CCO, and SBO, respectively; SEM=50.4). There were no interactions involving time in ruminal methane emission, which was greatest among treatments for CON (P &lt; 0.05) in MJ/d (1.39, 0.93, 0.90, 0.92, 0.85, and 0.96; SEM=0.069) and relative to digestible energy intake (20.6, 15.7, 16.8, 16.1, 13.7, and 13.9% for CON, MSL, HSL, ION, CCO, and SBO, respectively; SEM=1.223). In conclusion, dietary inclusion of Sericea lespedeza may offer a natural and sustainable means of decreasing ruminal methane emission by hair sheep as previously shown in goats, with a magnitude of impact similar to that of some other supplemental dietary ingredients.

Effect of ‘Serala’ Sericea Lespedeza (Lespedeza Cuneata) Hay on Gastrointestinal Parasite Fecal Egg and Oocysts Counts and Packed Cell Volume in Goats

Fifty-two naturally parasite-infected intact male Spanish goats 6–7 mo of age were used in a 6-wk trial to investigate effects of ‘Serala’ (SER) sericea lespedeza (SL; Lespedeza cuneata) on indicators of gastrointestinal parasitism. Goats were individually housed in 1.5 x 1.5 m pens. Treatments were pure SER (n = 18) or ‘AU-Grazer’ (AUG; n = 16) varieties of SL or bermudagrass hay (n = 18; CON) at 75% of the ration. A corn-soybean meal-based supplement (25% of the ration) ensured isonitrogenous (17% crude protein), isocaloric diets. Diets were fed to 10% orts. Treatments were assigned for similar initial group mean fecal egg count (FEC). At the start of the study (D 0) and weekly thereafter, FEC and coccidia oocyst counts (FOC) were conducted via a modified McMaster’s technique [eggs per gram (epg); oocysts per gram (opg)], and percentage packed red blood cell volume (PCV) was measured via microhematocrit centrifugation. Data were analyzed using a mixed model for repeated measures. There was a treatment by time interaction (P &lt; 0.001) for FEC. In week 1, SER and AUG were lower (P &lt; 0.02) than CON and were higher than control at week 6 (AUG tendency only, P &lt; 0.10; SER, P &lt; 0.02). The FOC were impacted by treatment (P &lt; 0.008), averaging 1977 ± 945 opg for AUG (lowest, P &lt; 0.01), 3558 ± 876 opg for SER and 4164 ± 955 opg for CON (SER and CON similar). Percentage PCV tended (P &lt; 0.09) to be influenced by a treatment by time interaction in which AUG and SER were similar over time, while PCV for CON animals was lower (P &lt; 0.03) than D 0 at all sampling points after the first week. Overall, there was no effect of SER on FEC or FOC and no effect of AUG on FEC, though PCV was maintained throughout the study for both SL treatments.