Grass-Legume pastures to increase economic and environmental sustainability of livestock production

Grass-Legume pastures to increase economic and environmental sustainability of livestock production

Summary

The objective of this research is to determine the potential of grass-legume pastures in comparison to grass monocultures. During this year, we reported that steers have better gains when grazing tall fescue grown in a mixture with either high- or low-tannin legumes, as compared to grass fertilized and unfertilized monocultures. However, the yearly forage yields in the mixtures were slightly lower than fertilized tall fescue, but results of our small-plot studies suggest that certain ratios of grass-legume mixtures are as productive as fertilized grass monocultures. In addition, our ruminant digestion studies have elucidated the effect of legumes on ruminal fermentation and gas production, showing that grass-birdsfoot trefoil mixtures favorably produced less ammonia-N and methane. Overall, these results suggest that grass-legume mixtures can improve livestock and pasture productivity and sustainability.

Objectives/Performance Targets

Three objectives and accompanying performance targets are listed below.

Objective 1. Compare livestock performance, economics and subsequent carcass characteristics from beef grazing grass monocultures and low- and high-tannin grass-legume mixtures versus traditional feedlot-based finishing.

Year 1: Begin grazing (plots established in 2009); measure feed intake, body weight, dry matter and nutrient digestibility (crude protein and fiber); and determine feed efficiency, and plasma urea nitrogen during growing and finishing periods.

Year 2: Collect second year data on feed intake, body weight, and dry matter and nutrient digestibility; determine feed efficiency, and plasma urea nitrogen during growing and finishing period; and develop fact sheets for use at pasture walks and field days.

Year 3: Conduct continuous culture study using feed samples collected from growing and finishing periods to investigate ruminal fermentation characteristics (ammonia-N, VFA, methane, microbial protein synthesis and digestibility); evaluate meat quality of steers slaughtered after the finishing period in year 1 and 2 (FA analysis, tenderness, sensory panel evaluation, and lipid and color stability measurements); and revise fact sheets for symposium.

Year 4: Complete data analysis; and prepare journal manuscript(s).

Objective 2. Determine best possible grass-legume mixtures and plant densities that maximize pasture productivity and nutritional quality.

Year 1: Plot establishment (seed plots and measure frequency of establishment).

Year 2: Begin grazing and collect first year of plot yield, nutritional quality and stand frequency; develop NIRS equation that separates species composition; and develop fact sheets for use at pasture walks and field days.

Year 3: Collect second year of plot yield, nutritional quality and stand frequency; and begin data analysis.

Year 4: Complete data analysis; revise fact sheet(s) and prepare journal manuscript.

Objective 3. Determine the effects of tannins on nutrient cycling in grazing systems.

Year 1: Pasture establishment; and collect baseline soil and leachate data.

Year 2: Begin grazing and collect first year of soil, plant and leachate data; sample analyses; and develop fact sheets for use at pasture walks and field days.

Year 3: Second year of collection of soil, plant and leachate data; sample analyses; and begin data analysis.

Year 4: Complete data analysis; revise fact sheet(s) and prepare journal manuscript.

Accomplishments/Milestones

Objective 1. Compare livestock performance, economics and subsequent carcass characteristics from beef grazing grass monocultures and low- and high-tannin grass-legume mixtures versus traditional feedlot-based finishing.

Milestones for Year-1, -2, and -3 have been completed and we are nearing completion of Milestone for Year-4 (data analysis and manuscript preparation).

The second year’s data were collected on the study evaluating beef steers’ performance while grazing tall fescue (TF) pastures with or without nitrogen fertilizer or with low- and high-tannin legumes. Animal growth performance, ruminal fermentation, carcass characteristics, forage yield and available forage nutritive value were evaluated. The data are being analyzed and prepared for manuscripts. In response to grass-legume mixtures, the average daily gains (ADG) were significantly different at 1.6, 1.5, 1.3 and 0.9 lb/day for tall fescue+birdfoot trefoil (TF+BFT), tall fescue+alfalfa (TF+ALF), tall fescue+nitrogen fertilizer (TF+NF) and tall fescue with no nitrogen fertilizer (TF-NF) treatments, respectively. Carcass quality of the grass/legume finished beef was not significant among treatments, grading an average of Select, with the trend for TF-NF to be slightly lower at Select minus. Forage yield varied among treatments with total seasonal yields (lbs dry matter) of 4167, 3841, 3615 and 2314 lbs/acre for TF+NF, TF+BFT, TF+ALF and TF-NF, respectively. It was found that the tall fescue-legume mixtures had higher total digestible nutrients (TDN) (59.3%) than the tall fescue monocultures (55.4%). Overall, these results suggest that grass-legume mixtures can improve livestock and pasture productivity and sustainability. This segment of the research is being conducted in partial completion of a M.S. thesis (Bingham, T.J.).

Chemical analysis (ruminal fermentation profiles and long-chain fatty acid profiles of adipose tissue and muscle) from 2012 and 2013 grazing experiments with the four treatments (TF-N, TF+NF, TF+ALF, TF+BFT) is being completed. Continuous culture studies were completed and resulted in two new peer-review publications in 2013. The first found that when adding a source of energy such as ground corn, TF+BFT had better ruminal fermentation efficiency than TF-ALF, TF+NF and TF-NF treatments. The second manuscript evaluated varying levels of the legume in the diet and concluded that increasing the proportion of legume in a mix with tall fescue favorably shifted in-vitro fermentation pathways such that less ammonia-N and methane were produced. This work was conducted as part of a Ph.D. dissertation which was presented and defended in July 2013 (Noviandi, C.T.).

During 2013, these results were presented at the joint Utah State University/Western SARE Grass-Legume Project pasture field tour, as part of a Ph.D. defense, and at multiple professional meetings including the International Grassland Congress and International Annual Meetings of the ASA/CSSA/SSSA as noted in the impact/Contributions section.

Objective 2. Determine best possible grass-legume mixtures and plant densities that maximize pasture productivity and nutritional quality.

Milestones for Year-1, -2, and -3 have been completed for this objective. Milestone for Year-4 (data analysis and manuscript preparation) is in process.

Field data collection of the small plot study comparing productivity of grass-legume mixtures with fertilized and unfertilized grass monocultures was completed in September, 2013.  Final forage quality data collection will be completed winter of 2014. This constituted the research portion of Steve Cox’s MS thesis, which was presented and defended in August, 2013. In brief, small plots of binary mixtures of five grasses [orchardgrass (OG), tall fescue (TF), meadow brome (MB), timothy and perennial ryegrass (PR)] and three legumes [alfalfa (AF), birdsfoot trefoil (BF) and cicer milkvetch (CM)] were established, and yield data was collected for three years (2011, 2012, 2013). Ratios in the mixtures included 0, 25, 50 and 75% legume composition. Results revealed that TF, OG and MB grass-legume mixes averaged 6.0, 5.0 and 14.0% higher forage production than their respective grass monocultures. The highest seasonal forage production of tall fescue combinations were 6.6 ton/acre TF:AF (50:50), 6.3 ton/acre TF:BF (50:50) and 5.2 ton/acre TF:CM (50:50). Highest forage production of orchardgrass combinations were 5.5 ton/acre OG:AF (50:50), 4.9 ton/acre OG:BF (50:50) and 3.9 ton/acre OG:CM (75:25). Highest seasonal forage production of meadow bromegrass combinations were 6.1 ton/acre MB:AF (50:50), 5.8 ton/acre (50:50) and 4.9 ton/acre MB:CM (50:50). These results suggest that grass-legume mixtures can be an effective strategy to improve pasture productivity.

During 2013, these results were presented at the joint Utah State University/Western SARE Grass-Legume Project pasture field tour and in a M.S. thesis defense.

Objective 3. Determine the effects of tannins on nutrient cycling in grazing systems.

Milestones for Year-1 and -2 have been completed for this objective. The milestones for Year-3 will be completed this spring and work is underway on milestones for Year-4 (data analysis and manuscript preparation).

This study was conducted using the same pastures (TF+BFT, TF+ALF, TF+NF and TF-NF) used in the animal performance study. Soil samples were taken at the beginning and end of the grazing season in 2012 and 2013 to a depth of 150 cm. Leachate samples were taken biweekly throughout the 2012 and 2013 growing and grazing season and will continue, as possible, through the spring of 2014. Soil and leachate samples are currently being analyzed for total nitrogen (N) and available nitrogen (ammonia and nitrate). Plant samples were taken before, and after, grazing events and will be analyzed for N. A mass balance approach is being utilized to estimate N losses due to volatilization. 

During 2013, these results were presented at the joint Utah State University/Western SARE Grass-Legume Project pasture field tour and in a M.S. thesis defense.

Impacts and Contributions/Outcomes

Results to date indicate that steers have better gains when grazing tall fescue grown in a mixture with legumes versus in grass monocultures, with the mixture using birdsfoot trefoil resulting in the highest gains. Yearly forage yields are slightly lower than fertilized tall fescue, but results of small-plot studies suggest that certain grass-legume mixtures are as productive as fertilized grass monocultures and that specific ratios between grasses and legumes can even increase forage production. Digestion studies have elucidated the effect of legumes on ruminal fermentation and gas production, with results showing that grass-birdsfoot trefoil mixtures favorably producing less ammonia-N and methane. Completion of analysis of leachate samples will elucidate the effect of grass-legume mixtures on groundwater. Overall, this information is adding to the knowledge-base about grazing grass-legume mixtures. The results have indicated that the use of synthetic fertilizer can be reduced without negatively affecting forage and livestock production. Completion of economic and environmental analyses should lead to increased producer adoption and increased agricultural sustainability. 

To date, multiple on-farm and research station field tours have demonstrated these findings to approximately 400 participants. Many of the participants were producers and ranchers, including those from small, family-owned operations. Follow up questions have indicated that many of these participants are implementing grass-legume mixtures in their operations in an effort to increase economic and environmental sustainability. The largest of these field tours was the joint USU/Western SARE project grass-legume symposia-type tour which was held in the summer of 2013 and highlighted in the Western SARE quarterly newsletter. In addition, the results from this research have been presented at eight regional, national and international professional meetings, garnering attention from all over the world. The results have been published in five peer-reviewed articles or proceedings, and additional manuscripts are being prepared. Specific outreach presentations and publications are listed below. Those new for this yearly report are signified by “**”.

WSARE PROJECT SW10-088: TOURS, PRESENTATIONS, AND MANUSCRIPTS

FIELD TOURS (TO DATE – SORTED OLDEST TO MOST RECENT):

Ward, R. and B.L. Waldron. 2010. Franklin County Idaho Crop and Weed Tour. Tall fescue-legume mixtures to improve pasture sustainability. WSARE grass-legume grazing plots on-farm field tour. Preston, ID. July 20, 2010. (Impact: 40-50 producers in attendance).

Waldron, B.L. 2010. Utah State University Pasture Research Workshop. Breeding and performances of pasture grasses and legumes. Utah State University Intermountain Irrigated Pasture Research Facility. Lewiston, UT. July 22, 2010. (Impact: 80-100 producers and extension personnel in attendance).

Heaton, K. Utah Cattleman’s Summer Tour. WSARE grass-legume grazing plots on-farm field tour. Panguitch, UT. August 03, 2012. (Impact: 30-50 ranchers in attendance).

Heaton, K. Pasture walk for local conservation district and watershed committee. WSARE grass-legume grazing plots on-farm field tour. Panguitch, UT. Sept 06, 2012. (Impact: 20-40 participants).

**Bingham, T.J., B.L. Waldron, E. Creech, D.R. ZoBell, and R. Miller. Utah State University Pasture Field Day. Plant and animal performance in grass/legume pastures. Lewiston, UT. July 31, 2013. (Impact: 150 attendees of which many represented small, family-owned, farm and ranches. Also was part of the WSARE AC Summer meeting Cache Valley tour).

**Noviandi, C. T., J.-S. Eun, D. R. ZoBell, and B. L. Waldron. Utah State University Pasture Field Day. Fatty acid profiles in adipose tissue of grazing beef steers. Lewiston, UT. July 31, 2013. (Impact: 150 attendees of which many represented small, family-owned, farm and ranches. Also was part of the WSARE AC Summer meeting Cache Valley tour).

**Peel, M.D., S.R. Cox, J.E. Creech, and B.L. Waldron. Utah State University Pasture Field Day. Production and nutritional benefits of including legumes in pastures. Lewiston, UT. July 31, 2013. (Impact: 150 attendees of which many represented small, family-owned, farm and ranches. Also was part of the WSARE AC Summer meeting Cache Valley tour).

**Miller, R. Utah State University Pasture Field Day. Nitrogen leachate from grazing grass/legume pastures. Lewiston, UT. July 31, 2013. (Impact: 150 attendees of which many represented small, family-owned, farm and ranches. Also was part of the WSARE AC Summer meeting Cache Valley tour).

PROFESSIONAL MEETINGS AND PRESENTATIONS (TO DATE – SORTED OLDEST TO MOST RECENT):

Noviandi, C. T., J.-S. Eun, D. R. ZoBell, R. D. Stott, B. L. Waldron, and M. D. Peel. 2011. Growth performance and carcass characteristics of beef steers grazing tall fescue without or with nitrogen fertilization. Pages 337–340 in Proceedings, Western Section, American Society of Animal Science, Montana State Univ., Miles City, MT, June 2011.

Noviandi, C. T., R. E. Ward, J.-S. Eun, D. R. ZoBell, R. D. Stott, T. Astuti, B. L. Waldron, and M. D. Peel. 2011. Fatty acid profiles in adipose tissue of grazing and feedlot beef steers. J. Anim. Sci. 89 (E-Suppl. 1):617. (Abstr.). Joint Annual Meeting of ADSA-ASAS, July 2011.

Noviandi, C. T., M. N. McDonald, D. R. ZoBell, J.-S. Eun, M. D. Peel, and B. L. Waldron. 2012. Effects of energy supplementation for pasture forages on in vitro ruminal fermentation in continuous cultures. J. Dairy Sci. 95 (Suppl. 2):45 (Abstr.).

Cox, S.R., M. Peel, B. Waldron, and E. Creech. Maximizing forage production with grass-legume mixtures of tall fescue, orchardgrass, meadow brome, alfalfa, birdsfoot trefoil, and cicer milkvetch in three ratios.  2012. Joint annual meeting of the Western Society of Crop Science and Western Wheat Workers.  July 11-13, 2012. Pullman, WA.

Cox, S.R., M.D. Peel, B. Waldron, and E. Creech.  2012. Forage production of grass-legume mixes in three ratios with tall fescue orchardgrass, meadow brome, alfalfa, birdsfoot trefoil, and cicer milkvetch. ASA, CSSA, and SSSA, International Annual Meetings. Oct. 21-24, 2012. Cincinnati, OH.

**Bingham, T.J., B.L. Waldron, E. Creech, D.R. ZoBell, and R. Miller. 2013. Plant and animal performance in grass/legume pastures. Western Soc. of Crop Science Annual meetings. June 11-12, 2013. Pendleton, OR.

**Noviandi, C. T., R. E. Ward, J.-S. Eun, D. R. ZoBell, R. D. Stott, B. L. Waldron, and M. D. Peel. 2013. Fatty acid metabolism on pasture- and feedlot-finished cattle. Pages 585–586 in Proceedings, 22nd International Grasslands Congress. Sept 15-19, 2013. Sydney, Australia.

**Bingham, T.J., B.L. Waldron, E. Creech, D.R. ZoBell, and R. Miller. 2013. Plant and animal performance in grass/legume pastures. Abstr. 113-9. ASA, CSSA, and SSSA, International Annual Meetings. Nov. 3-6, 2013.Tampa Bay, FL.

DISSERTATION AND THESIS DEFENSE:

**Noviandi, Cuk Tri. Ph.D. Dissertation defense and seminar. Growth Performance and Nutrient Metobolism of Pasture-Finished Beef Steers and In-Vitro Fermentation Characteristics of Pasture Forages in Continuous Cultures. Dept of Animal, Dairy, Veterinary Sciences, Utah State University. July 16, 2013.

**Cox, Steven. M.S. Thesis defense and seminar. Forage Yield and Quality of Binary Grass-legume mixtures of tall fescue, orchardgrass, meadow brome, alfalfa, birdsfoot trefoil and cicer milkvetch. Dept. Plant Sciences, Utah State University. August 9, 2013.

PAPERS IN PROCEEDINGS (PEER REFERRED):

**Noviandi, C. T., R. E. Ward, J.-S. Eun, D. R. ZoBell, R. D. Stott, B. L. Waldron, and M. D. Peel. 2013. Fatty acid metabolism on pasture- and feedlot-finished cattle. Pages 585–586 in Proceedings, 22nd International Grasslands Congress, Sydney, Australia, New South Wales Department of Primary Industry, Kite St., Orange New South Wales, Australia.

EXTENSION BULLETINS:

None to report.

PEER REVIEWED JOURNAL ARTICLES (TO DATE – SORTED OLDEST TO MOST RECENT):

Noviandi, C. T., R. E. Ward, D. R. ZoBell, R. D. Stott, B. L. Waldron, M. D. Peel, and J.-S. Eun. 2012. Fatty acid composition in adipose tissue of pasture- and feedlot-finished beef steers. Prof. Anim. Sci. 28:184–193.

Noviandi, C. T., B. L. Waldron, J.-S. Eun, D. R. ZoBell, and M. D. Peel. 2012. Growth performance, ruminal fermentation profiles, and carcass characteristics of beef steers grazing tall fescue without or with nitrogen fertilization. Prof. Anim. Sci. 28:519–527.

**Noviandi, C. T., J.-S. Eun, M. D. Peel, B. L. Waldron, B. R. Min, D. R. ZoBell, and R.L. Miller. 2014. Effects of energy supplementation in pasture forages on in vitro ruminal fermentation characteristics in continuous cultures. Professional Animal Scientist. 30:13-22.

**Noviandi, C. T., K. Neal, J.-S. Eun, M. D. Peel, B. L. Waldron, D. R. ZoBell, and B. R. Min. 2014. Comparison of alfalfa, birdsfoot trefoil, and cicer milkvetch in combination with 25, 50, 75% tall fescue in a continuous-culture system. Professional Animal Scientist. 30:23-32.

• Prof. Anim. Sci. Jouranl article_In vitro fermentation of tall fescue-legume mixtures in different ratios
• Prof. Anim. Sci. Journal article_Effects of energy supplement in grass-legume mixtures on in-vitro ruminal fermentation
• Cox, Peel, et al._USU and WSARE Pasture field day handout on different ratios of legumes with grass
• Bingham_ASA,CSSA,SSSA meeting presentation_livestock performance on tall fescue-legume mixtures
• Bingham, Waldron, et al._USU and WSARE Field day handout_Plant and animal performance in mixed tall fescue-legume pastures
• WSARE Simply Sustainable Oct 2013_USU and WSARE Pasture field day article

Collaborators: