Duration: 10/01/2009 to 09/30/2014

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Statement of Issues and Justification

The landscape and climate of the Western U.S. provide abundant range and agricultural lands suited to grazing and forage production, leading to a dominance of cow-calf and ewe-lamb systems in this region. The nutritional value of forages, particularly those grazed from rangeland, is highly variable in space and time, with nutrient content often limiting high levels of livestock production. The development of scientifically sound nutritional management tactics for livestock in variable and often extensive conditions presents unique challenges to researchers. Increased knowledge of the mechanisms of herbivory, digestion, and forage utilization can contribute to improved nutritional status and productivity of livestock, improved economic efficiency in forage-based livestock production systems, and improved sustainability in ranching enterprises, and the rural communities that depend upon them. A multitude of issues challenge livestock producers throughout the West, but maintaining economic viability is the most important. Improving the proportion of forage nutrients converted to animal products based on sound, science-based management strategies is the most viable means of achieving improved biological efficiency. However, production systems that optimize livestock efficiencies cannot do so at the expense of the environment. Systems that concomitantly improve livestock and landscape responses need to be used. For example, tactics leading to increased conversion of nutrients to productive purposes in the animal also lead to reduced nutrient loading in air, soil, and water through decreased animal excretion of gases and underutilized nutrients. Additionally, understanding and controlling animal factors affecting herbivory and distribution of livestock in extensive environments adds to our ability to minimize animal impacts on the environment. The focus of this Multistate Research Project is to contribute to our basic understanding of processes in (1) the plant-animal-landscape interface, (2) nutrient digestion and utilization from forages, and (3) nutritional management strategies based on grazed or harvested forages. The intent is to improve livestock digestive, metabolic, behavioral, production, and integrated system responses and to facilitate transfer this information to users such as livestock producers or land management personnel. Continuous communication and collaboration among scientists working in this discipline can promote more rapid development and transfer of new knowledge related to sustainable livestock production from forage-based systems. Research focusing on development of economically and environmentally sustainable forage-based production systems will contribute toward the ESS 2005-2010 national research priority to manage natural resources in a manner to improve the environment and the economy. Successful research in this field will also work toward the ESS priority of helping rural communities thrive by providing access to and application of new technologies relative to overcoming nutrient limitations for forage-fed livestock in the Western U.S.

Related, Current and Previous Work

Estimating Forage Intake Using n-Alkanes


Advantages
Estimation of forage intake using n-alkane ratio has been found to be more precise than those obtained with chromium oxide and in vitro digestibility in both cattle (Oliveira et al., 2007) and sheep (Dove et al., 2000).  Estimation of fecal output from a dosed marker and diet digestibility from in vitro incubation of diet samples has several disadvantages, ranging from inadequacy of the in vitro technique to problems associated with the estimation of fecal output (Dove and Mayes, 1996).   The alkane method gives individual-animal intakes and can be used where animals are receiving feed supplements (Mayes and Dove, 2002).  Also, GC analysis allows for both plant and dosed markers to be determined at the same time, which can limit analytical error bias.  It is also not necessary to obtain absolute fecal concentrations, since a ratio of the concentrations in feces is used (Mayes and Dove, 2002).  The use of controlled-release devices (CRD) of n-alkanes may also minimize the measurement errors associated with diurnal and/or daily variations on fecal concentration of markers. 


Forage intake can also be accurately estimated from a combination of known supplement intake and an estimate of diet composition, which replaces the need for separate alkane dosing to estimate intake (Clark et al., 2004; Elwert and Dove, 2005).  If a supplement has or can be labeled with alkanes, the proportion of the supplement in the diet can be determined (Dove and Olivan, 1998).  Therefore, if the supplement intake is known, total herbage intake can be determined by proportion (Dove et al., 2002).  This would remove the need for controlled-release devices.  However, supplement might have to be feed everyday to decrease errors associated with diurnal and/or daily variations of fecal concentration of markers.  A supplement labeled with beeswax is one method that could replace the use of alkane CRD.  The inclusion of beeswax-labeled supplements to estimate intake has shown to estimate intake accurately (Dove and Olivan, 1998; Elwert and Dove, 2005). 


Disadvantages
A plant wax (odd-chain) alkane is used as an internal digestibility marker and at the same time the dose synthetic (even-chain) alkane is used as the fecal-output marker.  Since an odd-chain alkane is used as the internal marker, a representative diet sample is required for analysis of its alkane content.  Fecal alkanes can be used to determine diet composition in monospecific pastures, which may remove the need to take diet samples.  The estimate of the diet composition provides estimates of the alkane concentrations of the whole diet, with which intake can then be estimated.  However, under grazing conditions, the diet composition may vary due to selective grazing and/or variation in forage species.  As alkane concentrations can differ for different plant parts and plant species, thus forage may need to be sampled for analysis.  The number of alkanes, and the differences in their concentration between the components, limits the number of botanical components that can be distinguished in a mix, whether determined by solving simultaneous equations (Dove, 1992) or by least squares methods (Dove and Moore, 1995).  Thus, species with similar alkane compositions may be grouped, and each group considered a botanical component (Bugalho et al., 2002).  However, the accuracy of diet composition estimates is likely to decline as the number of dietary components increases (Mayes and Dove, 2000).  Furthermore, Lee (2004) and Lee and MacGregor (2004) found that alkanes alone are unlikely to provide good estimates of the composition of the diet when ruminants are grazing complex pastures compared to using microhistology or physical separation.  Therefore in complex pastures, rumen cannulated animals are required to obtain a representative sample of consumed forage. 


According to Mayes and Dove (2000), the use of alkane markers to estimate diet composition there are four aspects that need to be addressed to evaluate and optimize the technique:  1) more validations of the technique; 2) procedures for statistical analysis of diet composition data to be developed; 3) potential weighting procedures to optimize the discriminatory power of diet composition markers need to be explored and 4) procedures need to be developed that allow marker systems to be used in situations where the number of potential dietary components exceeds the number of available markers.


Shortcoming of the 1996/2000 Beef NRC for Cows Grazing in Western Rangeland Environments


Observational field data and peer reviewed research have identified deficiencies in the 1996/2000 Nutrient Requirements of Beef Cattle with respect to maintenance requirements and forage intake on rangelands. Lardy et al. (2004) reported that predicted energy deficits for summer-calving cows grazing either range or subirrigated meadow in November were biologically unreasonable. They further recommended that the On Pasture function in the nutritional model not be used because it unreasonably increases energy requirements. In most instances, cow performance field data agree with the findings of Lardy et al. (2004), though there have been some studies where predicted forage intake for dormant forage exceeded estimated forage intake (Cr marker calculated; Bodine and Purvis, 2003).


Earlier researchers have attempted to measure energy expenditure for cattle grazing native rangelands by expressing energy expenditure as kcal metabolizable energy (ME) per unit of metabolic body weight (Havstad and Doornbos, 1987; Morris and Sanchez, 1987). Measuring ME intake is a caloric accounting of a cows daily life and encompasses net energy (NE) for gain, lactation, conception, maintenance, and the heat increment of intake energy or


ME = NEg + NEl + NEy + NEm + HiE


in the 1996 NRC formula. With some difficulty, estimated milk production can be determined by such techniques as weigh-suckle-weigh (Williams et al., 1979) and a body of research exists to allow the estimation of milk production from weaning weights (Fox et al., 1988). From this information, NEl can be estimated. Net energy for gain can be calculated from cow weight changes and body condition scores using the Atwater physiological fuel values for varying body compositions (Lemenager et al., 1991; NRC, 1996). Tabular values are available from NRC (1996) to estimate NEy required at various stages of gestation. The last two NE components in the inclusive ME requirement are more problematic. By its nature, the HiE requires inclusion of the energy cost for the activity of harvesting forage in a rangeland setting. Also, NEm assumes a prescribed efficiency of energy utilization for maintenance. The calculated values used for NEm were originally generated with mostly idle animals in either a calorimeter or feedlot setting. Hence, two main problems are associated with using the NEm system in rangeland settings: (1) failure to adequately account for plasticity or adaptations that often occur with range animals as high energy demand visceral tissues (Ferrell, 1988) shrink and expand in response to nutrient availability and demands (Forbes, 1986) in a much greater fashion than would be expected with less dynamic feedlot systems; and (2) failure to accurately assess activity levels and nutrient demands of cattle grazing rangelands thus generating unreasonable maintenance requirements, especially with dormant forage.


In the NRC (1996) Beef Requirements book, it is stated on page 11 that CSIRO reports that maintenance for pasture cattle increases by 10 to 20% for the best grazing conditions to 50% at its worse. An attempt is made by the NRC (1996) book to account for activity with the equation for NEmact. In most cases, it tends to greatly overestimate maintenance requirements for pasture cattle. For example, intake for ME was compared to NEmact + NEm for required forage intake to meet maintenance requirements. The ME requirement for a nonlactating 499 kg cow was expressed as (140 kcal per unit of metabolic body weight * 1.3 for activity) following Ferrell and Jenkins (1985) and Osuji (1974 with sheep). Forage intake was defined as 10.48 kg on 56% TDN pasture with forage availability of .8031 T/ha. The two different levels of intake were compared for hilly ground. Forage intake required for maintenance via ME was 9.48 kg, allowing for a weight gain of .13 kg/d (as calculated by 1.00 kg extra forage * .6174 Mcal Neg per kg forage ÷ 4.63 Mcal NEg/kg ADG). Forage intake required for maintenance via NEmact + NEm was 13.51 kg, resulting in a negative balance of -3.03 kg of forage or -3.63 Mcal NEm for a weight loss of approximately 1 kg/d {using 5 Mcal NE/kg mobilized tissue (Moe et al., 1971) and .70 efficiency of transformation (Thompson et al., 1983).


Another area that needs further research includes the discount that is suggested to be applied to forage intake for pastures having less than 1,150 kg/ha available forage. This does not seem to be a reasonable assertion to make with Western rangelands. For example, if a 454 kg cow needed to consume 8.88 kg of forage/d to maintain body weight and ate at a rate of 50 bites/min for 600 min/d, it would require that her average bite size equal 0.30 grams organic matter per bite. If the cow had a bite size of 14 sq. in, it would require about .0214 g/sq. in. forage density or around 336 kg/ha if forage production were uniform over the landscape. If light to moderate forage utilization is practiced, only harvesting 40% of available forage, then forage production of 840 kg/ha would suffice to practice good range management and to also allow cattle to practice some selectivity in grazing. This is assuming uniform production over a pasture. In semiarid parts of the West, forage may not be distributed evenly but may be distributed as clumps and grazing animals will travel from clump to clump in a forage limiting environment, thus increasing their harvesting efficiency.


As stated on page 95 of the 1996/2000 Nutrient Requirements of Beef Cattle, further research is needed to develop more accurate means of predicting intake by beef cattle fed all forage diets. Using existing and future data sets from western state experiment stations with extensive rangelands, we propose to assemble prediction equations that more accurately assess maintenance requirements and forage intake for grazing beef cattle.

Related Multistate Research Projects or Other Multistate Activities


Research focusing on sustainable production systems requires collaboration with researchers and educators within and outside the members of this Multistate Research Project. Overlap exists with the objectives of previous committees, such as those focusing on Managed Grazing Systems for the Intermountain West (WCC1002), Rangeland Resource Economics and Policy (WCC055), Animal Utilization of Products from Processing Agricultural Commodities (WCC203), and Coordination of Sheep and Goat Research (WCC039). Current committees with potential overlapping objectives include Improved Grazing Systems for Beef Cattle Production (NC225), Beef Cattle Grazing Systems that Improve Production and Profitability While Minimizing Risk and Environmental Impacts (NC1020), Sustaining Forage-based Beef Cattle Production in a Bioenergy Environment (NC_TEMP1020), Beef-Cow-Calf Nutrition and Management Committee (NCERA_OLD087), Increased Efficiency of Sheep Production (NC_TEMP190), Coordination of Sheep and Goat Research and Education Programs for the Western States (WERA039), and Sustainable Small Ruminant Production in the Southeastern U.S. (SCC081). Members of this Multistate Research Project maintain communication with these groups through collaborative research efforts and attendance at meetings of these groups. Members of other committees are invited to attend this projects meetings to maintain communications relative to common goals. However, research objectives of this Multistate Research Project are unique to this committee in their emphasis on nutrition and behavior of ruminant livestock in the production systems of the arid and semi-arid West.

Objectives

1. Validate the utility and repeatability of the alkane assay for measuring fecal output by grazing ruminant animal.
   
2. Identify the shortcoming of the 1996/2000 Beef NRC for cows grazing in Western rangeland environments.
   
3. Disseminate and translate research-based management strategies to stakeholders for improving ruminant use in sustainable forage production systems.
   
4. Provide professional development and mentoring opportunities for committee participants, young scientists, stakeholders, and graduate students.
   

Methods

Validation of the Alkane Analysis Analytical procedures for n-alkanes will be approached in two phases. First, the NMSU Animal Nutrition Gas Chromatography Laboratory is currently developing a modification of the current published GC alkane analytical procedure. After modification, the procedure will be distributed to participating experimental stations (USDA-ARS, Fort Keogh & Mandan and UW) for validation of technique. Study 1 will include analysis of known long chain fatty acids for determination of repeatability, accuracy, and precision. Study 2 will include alkane analysis of diet or plucked range forage samples contributed by each participating station (AZ, CO, MT, NM, ND, SD, and WY). Each station will contribute samples for alkane analysis to evaluate repeatability of the analytical procedure as influenced by forage sample collection location and site of analysis. Secondly, AZ, SD, and WY will evaluate NIRS for use in n-alkane analysis by creating a NIRS calibration consisting of chemical reference method/near infrared (NIR) spectra pairs. In the proposed experiment, these calibration pairs will consist of NIR spectra from both plant and fecal material, and will involve several chemical reference values, namely natural and dosed alkanes, CP, and digestibility. In addition, fecal NIR spectra will be paired with observational data such as diet composition. The application of NIRS in agricultural and ecological research has advantages and disadvantages (Stuth et al., 2003; Foley et al., 1998). One advantage of NIRS is a reduced overall cost of analysis for a particular constituent of interest and another is the ability to apply the results from several chemical analyses to a single spectrum. We will obtain NIR spectra from all samples collected and will select approximately 30 percent of these for chemical analysis and calibration development. Of the 30 percent selected for chemical analysis, approximately 75 percent will be used for calibration and 25 percent for validation. NIRS calibration/validation samples will be selected based on spatial/temporal/expected chemical, and spectral diversity (Shenk and Westerhaus, 1991). Accuracy and precision of NIRS calibrations will be evaluated on the criteria of Williams (2004). Briefly this will include R2, standard error of cross validation (SECV), standard error of prediction (SEP), and the ratio of SECV to the standard deviation of the calibration dataset for each individual constituent. Modified partial least squares regression (Martens and Naes, 1987) will be used to develop predictive equations. Final calibration equations will be applied to all spectra to determine values for each constituent of interest at the completion of the experiment. Due to the multi-year aspect of the experiment, preliminary equations will be developed and applied to inform sample selection and to provide interim data for presentation at scientific meetings. Obtaining a Representative Diet Sample Like other intake methods requiring the analysis of dietary samples, a representative diet sample is essential for analysis of alkane content. The intent of this Multistate Research Project is to develop an accepted standardized procedure for collection of diet samples for alkane analysis. Participating experiment stations (AZ, CO, NM, USDA-ARS @ Fort Keogh and Mandan, and UW) will collect diet extrusa samples and fecal grab samples from no less than 3 cannulated cows for 3 consecutive days, and at 2 different collection times (morning vs. evening). Individual and composite (by day, cow and collection time) diet and fecal samples will be analyzed for alkane content using the modified analytical procedure developed by the NMSU Animal Nutrition Laboratory. As an alternative approach, grazing observational data will include bite rate, bite size, time stamp, and diet selection using vocally activated software following the procedure reported by Glasser et al. (2008). As observers record grazing behavior using this procedure, representative diet samples will be hand collected for later forage quality analyses for crude protein and digestibility (Tilley and Terry, 1963). Data from all sites will be pooled and analyzed as a factorial experiment. Estimating Intake in Controlled Environment of Forage and a Self-Fed Supplement An in vivo study where diet composition and intake are controlled will be conducted following the experiments described above. Forages will be of a mixed composition to represents major dietary components consisting of grasses, forbs, and shrubs. At least 2 of the participating experiment stations (NM, USDA-ARS @ Fort Keogh) will feed ruminally cannulated cows for a 14 d experimental period. Starting on d 1 cows will be dosed intraruminally with beeswax-labeled supplement (Elwert et al., 2004) that would be used as self fed supplement on range. Fecal bags will be harnessed on cows for 5 consecutive days starting on day 14. Total fecal collection will be recorded and a grab sample taken daily. Fecal bags will be weighed and emptied 2 times per day 12 hours apart. Intake will be estimated using equations of Mayes et al. (1986) and Charmely and Dove (2007). Marker recovery and Predicted vs. Actual intake will be compared using data collected from all participating experiment stations. Estimating Intake of Range Cows Grazing The final experiment will test the alkane method for its usefulness in the target setting. At least 3 experiment stations (AZ, NM, USDA-ARS @ Fort Keogh) will allow cows to graze either native range or improved pastures at one of three physiological stages (mid-lactation, late lactation, or after weaning). Following an adaption phase of 7 days to the pasture and vegetation, diet sample collections will occur up to the next 3 days (the sampling method is contingent on results of the previous experiment).Cows then will be equipped with fecal bags, and fecal grab samples will be collected when bags are changed. Diet samples will be analyzed for OM, CP, NDF, ADL, and either in vitro or in situ digestibility of DM and NDF. Quantitative intake and coefficients of variation will be calculated using in vitro or in situ indigestibility and total fecal output per fecal bags collections. The alkane technique will be compared with internal marker determination of indigestibility using ADL. A pulse-dose approach is an alternative method of sampling cattle for fecal output described in the above paragraph. At each of at least three locations, 30 beef cattle will be pulse dosed (Sprinkle et al., 2000; Giraldez et al., 2004; Bulang et al., 2007) with C32 alkane (dotriacontane, Acros Organics, Morris Plains, NJ) adsorbed onto 46 x 57 mm Whatman No. 1 qualitative filter paper (Whatman, Piscataway, NJ) that has been shredded and pressed into pellets following the procedures of Mayes et al. (1986) and Keli et al. (2008). A calibration study with penned cattle will be conducted to confirm the C32 alkane dosage rate for detection in the feces utilizing the improved gas chromatography-mass spectrometry procedure developed by Smith and Strickland (2007). We also wish to calibrate the dosage rate against near infrared reflectance spectroscopy (NIRS) prediction equations for alkanes which have had mixed success for even chain alkane predictions (Ru et al., 2002; Garnsworthy and Unal, 2004; Keli et al., 2008). If we used a similar pulse dosage rate of alkanes to that used by Giraldez et al. (2004), then adjusting from approximately 43 kg goats to 567 kg cattle would require a pulse dosage of 2,900 mg of dotriacontane or 39 g of pressed pellets, if adsorbed C32 on the filter paper was similar to Keli et al. (2008). We wish to see if some of the problems noted with detecting even chain alkanes by NIRS in feces noted in the literature (Ru et al., 2002; Keli et al., 2008) could be related to the low dosage rate in these studies or as the above scientists have intimated, that the dosed alkanes may not be adequately linked to structural entities to be picked up in the scan. This may require a calibration of alkane dosage against fecal concentrations in the aforementioned penned cattle study. In the field studies, pulse dosing will be used for estimating the concentration of fecal alkanes in order to minimize the disturbance of grazing behavior. The pulse dose of alkanes will be administered approximately 12 h before fecal sampling begins at 0600 h the following day. Observers will spot cattle with spray painted numbers, binoculars, and a range finder and fecal samples will be taken whenever observers see a cow defecating the first day from daylight to dusk. On the second and third days, samples will be collected at early morning, mid-day, and late afternoon. On the fourth day, samples will be taken at mid-morning and mid-afternoon. If observers are on horseback or on ATVs, cattle will be acclimatized to this activity prior to the trials. About 15 fecal samples will need to be analyzed per cow per sampling period per location. Evaluation of the 1996/2000 Beef NRC for Cows Grazing in Western Rangeland Environments Current published peer reviewed literature will be assessed and compared against the NRC 1996/2000 Nutrient Requirements of Beef Cattle for cattle grazing on Western rangelands. In conjunction with Objective # 1 Validate the utility and repeatability of the alkane assay for measuring fecal output by grazing ruminant animals, we will gather additional estimates of fecal output and forage intake at varying stages of production on rangelands varying in botanical composition, in particular C3 (cool season) vs. C4 (warm season) grasses. Cattle will be sampled at experiment stations in AZ, Hawaii, ND, NM, MT, SD, and WY corresponding to differences in herbaceous plant dominance: predominantly C3 grasses; mixtures of C3 and C4 grasses; and predominantly C4 grasses. Additional measurements beyond fecal output, estimated forage intake, and plant species composition will include forage production/ha, forage utilization, forage digestibility, soils classification, pasture size, terrain slope, elevation, temperature, and precipitation. Cattle behavior will be measured using GPS collars to determine location and traveling distances and with integrated sensors for head movement (Schauer et al., 2005; Ungar et al., 2005) to determine grazing times. Milk production will be estimated by either weigh-suckle-weigh (Williams et al. 1979) or by direct milking (Waterman et al., 2006) at least once for a subset of experimental cattle at each location. Additional descriptive data at the different experiment stations will include cattle breed and age, body condition score (Richards et al., 1986), cow weight, calving dates, frame score, and adjusted weaning weights (BIF, 2002). A subset of rumen cannulated cows may be utilized at each location to estimate diet selection and diet digestibility and intake following procedures developed with Objective #1. Alkane composition of both fecal and dominant forages will be evaluated following procedures developed with Objective # 1. Both intra- and inter-lab variability will be evaluated for collected samples. Data will be analyzed statistically using appropriate mixed model procedures for repeated measures (Littell et al., 1996; 1998).

Measurement of Progress and Results

Outputs

• Publish collaborative results demonstrating the effectiveness of procedures developed by this Multistate Research Project. Initially, abstracts and proceeding papers of the research will be presented at relevant regional and national meetings.
• Research manuscripts will be prepared from the data that is generated from these studies and submitted to recognized scientific journals.
• A series of Extension fact sheets will be written based on application of information in the journal articles. Segments of the fact sheets or summaries will be placed in Extension newsletters and local newspapers and livestock and forage-related magazines.
• Web-based information will be prepared with links and information on the project.
• Regional and state programs will be held to disseminate findings to stakeholders. For example, this Multistate Research Project is planning to hold the 4th Grazing Livestock Nutrition Conference in July, 2010.

Outcomes or Projected Impacts

• Procedures developed by this Multistate Research Project will allow for more efficient and effective estimates of grazed diet intake while minimizing the number of animals, sample collections, as well as animal behavior and environmental disturbances.
• Further refinement and enhanced application of the NRC 1996/2000 Nutrient Requirements of Beef Cattle for cattle grazing on Western rangelands. This will allow practitioners, Extension agents, and researchers to better match maintenance requirements for grazing beef cattle to what is actually observed in the field, which would enhance environmental stewardship.
• An economic assessment will be used to extrapolate impact statements for livestock producers, based on the proposed research. Enterprise budgets can then be prepared, which would include gross and net returns. Completed studies and the proposed research will provide a solid base from which an economic assessment can be made.
• Promote exchange of ideas, information, and data through sponsoring symposia or workshops on basic understanding of the plant-animal interface and resulting forage-based ruminant management strategies. These professional development activities will promote more rapid advancements in nutritional technologies.

Milestones

(2010): Work toward standardization of n-alkane procedures across states. Finalize and host the 4th Grazing Livestock Nutrition Conference.

(2011): Conduct field trials estimating fecal output in pen situations. Begin presenting abstracts and proceedings. Work towards submission of extramural grant to support the integrated activities described in the Methods section.

(2012): Conduct field trials estimating fecal output in grazing situations. Continue presenting results of research activities. Submit grant proposal.

(2013): Publish research finding related to n-alkane marker efficacy. Identify the strengths and shortcomings of the current Nutrient Requirements of Beef Cattle based on research results obtained from experiments conducted by this Multistate Research Project. Begin planning the 5th Grazing Livestock Nutrition Conference. Begin addressing areas of interest for project renewal.

(2014): Publish refereed and application articles summarizing recommendations for improving the current Nutrient Requirements of Beef Cattle for cattle grazing on Western rangelands. Continue planning of the 5th Grazing Livestock Nutrition Conference. Submit renewal before this Multistate Research Project terminates.

Projected Participation

View Appendix E: Participation

Outreach Plan

As described previously, this project will have a multi-faceted approach to transfer knowledge, skills, and technologies to stakeholders. This Multistate Research Project will facilitate collaborations, manuscript reviews, and develop new approaches to improve ruminant use of forages in Western rangeland environments. Initial transfer of information to the general public will occur through Extension faculty programming efforts. A series of Extension fact sheets will be written based on the journal articles. Segments of the fact sheets or summaries will be placed in Extension newsletters and local newspapers and livestock and forage-related magazines. Web-based information will be prepared with links to the project. Additionally, development of venues that will disseminate the expertise of members within the group, as well as, nationally and internationally recognized leaders in range livestock production will be a priority for this group. This Multistate Research Project will sponsor symposia or workshops on basic understanding of the plant-animal interface and resulting forage-based ruminant management strategies. For example, the 4th Grazing Livestock Nutrition Conference will be held in July, 2010.

Organization/Governance

The technical committee will organize and function in accordance with the procedures described in "Manual for Cooperative Regional Research." The voting members will elect three officers (Chair, Secretary, and Secretary-elect). These officers plus the immediate past Chair (after the first year) will constitute the executive committee. Specific task subcommittees and coordinators will be appointed as necessary to help coordinate activities among states. The executive committee will conduct any necessary business between annual meetings of the technical committee. The Chair will be responsible for presiding over the annual meeting of the technical committee, preparing the meeting agenda, appointing any necessary subcommittees, and for preparing the annual project report for the year ending with the meeting at which he presides. The Secretary will record and distribute the minutes of the annual meeting. At the end of the annual meeting, the Secretary will become Chair and the Secretary-elect will become Secretary.

Literature Cited

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