Progress 10/01/99 to 09/30/04
Outputs
An eastern NE study weaned March-born calves at 3 ages: 150, 210 and 270 days. Breakeven costs for finished steers favored normal and late-weaned calves. Pregnancy rates were not different. Mature cows have shown at similar weaning age, June-born calves average about 70 lbs less than March-born calves and weaning rates were similar (88%). Net returns from selling June-born calves in Jan. were about $70/calf higher than March-born calves sold in Oct. A study in western NE of pregnant yearling heifers found higher pregnancy rates for heifers supplemented to meet MP requirements (91%) compared to meeting CP requirements (86%). A 2-yr experiment evaluated the influence of supplemental protein during the last trimester of gestation and grazing sub-irrigated meadow during the postpartum interval on pregnancy rates and calf growth in a March calving production system. Calves born to cows fed supplemental protein were heavier at weaning (P = 0.08) and had heavier carcass
weights (P = 0.11). An experiment evaluated effect of two different development systems on performance and economics of long yearling steer production. Intensive management of long yearling steers produced greater profitability if marketed after the wintering or grazing periods but not after finishing. Effects of summer grazing date and fall stocking rates on Sandhills upland vegetation are: 1) herbage disappearance did not increase proportionately to stocking rates and animal intake declined at some point between 1.0 and 2.0 AUM ha-1 stock rates; 2) herbage disappearance did not differ between 2.0 and 3.0 AUM ha-1 stocking rates; and 3) yields of cool-season graminoids declined the following growing season as fall stocking rates increased. Results from evaluation of big bluestem response to mid-May grazing followed by different timings and grazing frequencies through the remainder of the growing season: a mid-May grazing period had no effect on cumulative herbage allowance, increased
cumulative herbage disappearance, and increased leaf:stem ratios. In eastern NE grazing of pastures containing a mixture of warm-season grasses that were unfertilized, fertilized with 55 kg/N/ha, interseeded with birdsfoot trefoil, or interseeded with a mixture of several legumes, Illinois bundleflower, sainfoin, and several medics resulted in steer gains of 0.39, 0.67, 0.65 and 0.48 kg/d respectively. Soil P and soil-borne pests are critical factors for establishment of interseeded alfalfa and birdsfoot trefoil in smooth bromegrass pasture. A grazing study was conducted to determine the effect of timing and frequency of grazing big bluestem (Andropogon gerardii Vitman) on plant vigor, root structure, and rhizome structure. Averaged across all grazing strategies, total basal cover of the five seeded species declined from 17% prior to grazing in 1995 to 7.4% in 2003. A study was conducted from 1998 to 2001 to evaluate the effects of stocking rate and grazing frequency on herbage
dynamics, disappearance, and composition of a wet meadow dominated by cool-season vegetation. Cumulative standing crop disappearance and height reduction increased linearly with increasing stocking rate.
Impacts
More widespread use of legumes in warm- and cool-season pastures to improve forage quality and yield and reduce the need for nitrogen is expected.
Publications
- Volesky, J.D. and, Clark, R.T. 2003. Use of irrigated pastures and economics of establishment and grazing. p 83-100. In: Proc. The Range Beef Cow Symposium XVIII. Dec. 9, 10 and 11, 2003, Mitchell, Nebr.
- Awada, T., Perry, M.E.L., and Schacht, W.H. 2003. Ecophysiological responses of a C3 grass and a C4 grass to tree canopy cover. Can. J. Plant Sci. 83:533-540.
- Mousel, E.M., Schacht, W.H., and Moser, L.E. 2003. Summer grazing strategies following early-season grazing of big bluestem. Agron. J. 95:1240-1245.
- Patterson, H.H., Adams, D.C., Klopfenstein, T.J. , Clark, R.T., and Teichert, B. 2003. Supplementation to meet metabolizable protein requirements of primiparous beef heifers: II. Pregnancy and economics. J. Anim. Sci. 81:563-570.
- Patterson, H.H., Klopfenstein, T. J., Adams, D.C., and Musgrave, J.A. 2003. Supplementation to meet metabolizable protein requirements of primiparous beef heifers: I. Performance, forage intake, and nutrient balance. J. Anim. Sci. 81:800-811.
- Smart, A.J., Vogel, K.P., Moser, L.E., and Stroup, W.W. 2003. Divergent selection for seedling tiller number in big bluesem and switchgrass. Crop Sci. 43:1427-1433.
- Smart, A.J., Moser, L.E., and Vogel, K.P. 2003. Establishment and seedling growth of big bluestem and switchgrass populations divergently selected for seedling tiller number. Crop. Sci. 43:1434-1440.
- Smart, A.J., Moser, L.E., and Vogel, K.P. 2004. Morphological characteristics of big bluestem and switchgrass plants divergently selected for seedling tiller number. Crop Sci. 44:607-613.
- Smart, A.J., Schacht, W.H., Moser, L.E., and Volesky, J.D. 2003. Prediction of leaf/stem ratio using NIRS: a technical note. Agron. J. (in press).
- Tuna, Metin, Vogel, Kenneth P., Gill, Kulvindar S., and Arumuganathan, K. 2004. Cytogenetic characterization of smooth bromegrass genomes. Crop. Sci. 44:31-37.
- Volesky, J.D., Schacht, W.H., and Richardson, D.M. 2004. Stocking rate and grazing frequency effects on Sandhills meadows. J. Range Manage. (in press).
- Volesky, J.D., Anderson, B.E., and Nichols, J.T. 2003. Perennial forages for irrigated pasture. NebGuide G03-1502-A.
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Progress 10/01/02 to 09/30/03
Outputs
A study in western NE of pregnant yearling heifers found that pregnancy rate was higher for heifers supplemented to meet MP requirements (91%) compared to meeting CP requirements (86%). Heifers grazed upland range and meadow and were fed supplements 3 times weekly from mid-Sept. to late-Feb. Increasing amounts of meadow hay were fed from mid-Dec. through calving in March. Improvement in 2-year-old preg rate increased value of each bred heifer in the MP treatment $13.64 over heifers receiving the CP treatment. In eastern NE conventional system (CON) steers were transported to a feedlot, fed a finishing diet, and slaughtered. Value added system steers (VA) were wintered on cornstalks, grazed pasture, fed a finishing diet, and slaughtered. Calf-finished steaks (CON) had lower Warner-Bratzler shear force (WBS) values, and higher sensory ratings for tenderness, juiciness, flavor, and overall desirability than yearlings (VA). Calf-finished steaks improved in sensory
tenderness with aging while yearlings showed no improvement. Both groups had significantly lower WBS values with each 7-day increment of aging from 7 to 21 d. A study in progress indicates that soil P and soil-borne pests are critical factors for establishment of interseeded alfalfa and birdsfoot trefoil in smooth bromegrass pasture. Two studies were initiated in 2003 to determine soil nitrogen and carbon of different grass/legume mixtures and Sandhills subirrigated meadows dominated by either cool-season or warm-season grasses. Above-ground herbage production and litter mass and root yields also are being estimated to compare quantity and distribution of nitrogen and carbon in the various plant communities. Pasture research is being conducted to determine the distribution of forage dry matter and nutrient removal through the growing season (May-Oct.) on different mixtures of smooth bromegrass and various legumes. The effects of stocking rate and grazing frequency on herbage dynamics,
disappearance, and composition of a wet meadow dominated by cool-season vegetation were evaluated. Stocking rate was significant for all response variables measured while grazing frequency only affected percentage of tillers of key species grazed. Cumulative standing crop disappearance and height reduction increased linearly with increasing stocking rate. Disappearance was 1,920, 2,700, and 3,090 kg ha-1 for the 148, 296, and 444 AUD ha-1 stocking rates, respectively. Percentage of tillers grazed and percentage height reduction increased with stocking rate for both slender wheatgrass and wooly sedge. For both species, percentage of tillers grazed was greater with 3 grazings compared to 5. Stocking rate or grazing frequency did not affect occurrence of the primary plant species or groups. Occurrence of legumes and Kentucky bluegrass (Poa pratensis L.) was higher in the grazed pastures compared to control. Grazing of taller grasses and sedges resulted in a more open canopy apparently
allowing lower-growing species to increase. A statewide grazing conference held in Aug had attendance of about 170.
Impacts
A significant increase in preg rates for 1st-calf heifers can be achieved at low cost by feeding supplement formulated to meet metabolizable protein (MP) needs vs crude protein (CP). The 5 percent increase in preg rate translates to about $14/hd improved value of the heifer which can have a cumulative effect over a number of years and a number of producers. The more tender and juicier steaks produced by calves versus yearlings could affect bottom line of producers if slaughter animals were sold based on those characteristics. With current marketing methods, slaughter weight tends to overwhelm quality so the yearling system due to this and cost differences had the highest economic impact. Prior research at UNL found that yearling cattle on smooth bromegrass-legume pastures had greater total weight gain than those on fertilized or non-fertilized smooth bromegrass. Improved establishment of legumes into smooth bromegrass has potential for economic payoffs to those
grazing bromegrass dominant areas. Determination of the impacts of stocking rate and frequency of grazing on key wet meadow grass species will permit management of the meadows to achieve economic and environmental goals.
Publications
- Awada, T., L.E. Moser, W.H. Schacht, and P.E. Reece. 2002. Stomatal variability of native warm-season grasses from the Nebraska Sandhills. Can. J. Plant Sci. 82:349-355.
- Clark, Dick, Walter Schacht, Don Adams, Terry Klopfenstein, and Wendy Miller. 2002. Making extended grazing work in Nebraska. Iowa Beef Center, Iowa State Univ. IBC-22, Nov. Anderson, R.V., R.J. Rasby, T.J. Klopfenstein, and C.N. Macken. 2002. An evaluation of production efficiency in a cow/calf system designed to add value. Proceedings, Western Section, Amer. Soc. Anim. Sci. 53:190.
- Creighton, K.W., C.B. Wilson, T.J. Klopfenstein, and D.C. Adams. 2003. Undegraded intake protein supplementation of compensating spring-born steers and summer-born steers during summer grazing. J. Anim. Sci. 81:791-799. (J. Ser. No. 13585)
- Awada, T., M.E.L. Perry, and W.H. Schacht. 2003. Photosynthetic and growth responses of the C3 Bromus inermis and the C4 Andropogon gerardii to tree canopy cover. Can. J. Plant Sci. 83:533-540.
- Burboa-Cabrera, F.R., W.H. Schacht, and B.E. Anderson. 2003. Utilization and grazing distribution of cattle at four stocking densities. J. Range Manage. 56:328-333.
- Iwig, N.M. 2003. Forage yield, quality, and utilization of a smooth bromegrass and birdsfoot trefoil pasture mixture. M.S. Thesis, Dept. of Agronomy and Horticulture, Univ. of Nebraska, Lincoln.
- Morris, J.W. 2003. Water-stress and defoliation effects on two warm-season grasses in the Nebraska Sandhills. M.S. Thesis, Dept. of Agronomy and Horticulture, Univ. of Nebraska, Lincoln.
- Mousel, E.M., W.H. Schacht, and L.E. Moser. 2003. Summer grazing srategies following early-season grazing of big bluestem. Agron. J. 95:1240-1245.
- Anderson, Rosemary, Rick Rasby, Terry Klopfenstein, and Casey Macken. 2002. Evaluation of cow and calf performance and profit potential in beef systems. In: 2003 Beef Cattle Report, Ag. Research Div., Univ. of NE-Lincoln, MP 80-A. P. 3-5.
- Jordan, D.J., T.J. Klopfenstein, and D.C. Adams. 2002. Dried poultry waste for cows grazing low-quality winter forage. J. Anim. Sci. 80:818-824.
- Lamothe, Mariela, Terry Klopfenstein, Don Adams, Jacki Musgrave, and Galen Erickson. 2002. Microbial protein production in gestating cows supplemented with different sources of rumen degradable protein grazing dormant range. In: 2003 Beef Cattle Report, Ag. Research Div., Univ. of NE-Lincoln, MP 80-A. P. 10-12.
- Lamothe, Mariela, Terry Klopfenstein, Don Adams, Jacki Musgrave, and Galen Erickson. 2002. Microbial protein synthesis and efficiency in nursing calves. In: 2003 Beef Cattle Report, Ag. Research Div., Univ. of NE-Lincoln, MP 80-A. P. 13-15.
- Loy, Tim, Don Adams, Terry Klopfenstein, Dillon Feuz, Jacki Musgrave, and Burke Teichert. 2002. Comparison of two heifer development systems on a commercial Nebraska ranch. In: 2003 Beef Cattle Report, Ag. Research Div., Univ. of NE-Lincoln, MP 80-A. P. 5-7.
- Loy, Tim, Terry Klopfenstein, Galen Erickson, and Casey Macken. 2002. Value of dry distillers grains in high-forage diets and effect of supplementation frequency. In: 2003 Beef Cattle Report, Ag. Research Div., Univ. of NE-Lincoln, MP 80-A. P. 8-10.
- Patterson, H.H., T.J. Klopfenstein, D.C. Adams, and J.A. Musgrave. 2003. Supplementation to meet metabolizable protein requirements of primiparous beef heifers I: Performance, forage intake, and nutrient balance. J. Anim. Sci. 81. (J. Ser. No. 13340).
- Patterson, H.H., D.C. Adams, T.J. Klopfenstein, R.T. Clark, and B. Teichert. 2003. Supplementation to meet metabolizable protein requirements of primiparous beef heifers II: Pregnancy and economics. J. Anim. Sci. 81. (J. Ser. No. 13349).
- Adams, D.C., and H..H. Patterson. 2003. Use of NRC Model to predict forage and/or energy intake and animal performance. p. 9-10 in Abstracts Am. Soc. Anim. Sci. Midwest Sec. Abstr. 37, Des Moines, IA.
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Progress 10/01/01 to 09/30/02
Outputs
In eastern NE two beef cow-calf systems were compared. In a conventional (CON) system cows remain on pasture to graze and are fed hay and supplement in winter. Calves are weaned and go directly to feedlot for finishing. In a value added (VA) system cows graze grass (spring, summer, fall) and corn stalks (late fall, winter). Calves are weaned and steers graze corn stalks, winter at low gains with forage and grain by-products, graze pasture in spring and summer and enter feedlot in fall and finish by late Dec. Preg rates were not different between systems. Feedlot feed efficiency was higher, ADG was lower and carcasses were lighter for CON compared to VA steers. VA system had greater profit compared to CON. In western NE effects of weaning date and winter protein supplementation were evaluated for spring calving cows. Treatments were wean Aug 18 or Nov 7, both with (P) and without supplemental protein (NP) to cows on range Dec 1 through March 1 (winter). Pregnancy rates
were similar for all 4 treatments. Weaning rates were 91.5 % for both weaning dates. Weaning rate was higher (93.5%) for NP cows than P cows (89.0%). Weaning weights for calves from NP cows were lighter than calves from P cows. For calves sold at weaning, net revenue was greatest for Aug weaned calves from NP cows and lowest for Aug weaned calves from P cows. When finished for slaughter net revenue was greatest for calves weaned in Nov from P cows and lowest for those weaned in Aug from P cows. In eastern NE grazing of pastures containing a mixture of warm-season grasses that were unfertilized, fertilized with 55 kg N/ha, interseeded with birdsfoot trefoil, or interseeded with a mixture of several legumes, Illinois bundleflower, sainfoin, and several medics resulted in steer gains of 0.39, 0.67, 0.65, and 0.48 kg/d, respectively. Similar pastures interseeded with single-species strips of 26 legumes in spring, 2001 had consistently acceptable legume stands in 2002 of red clover,
alfalfa, birdsfoot trefoil, and hairy vetch and occasionally acceptable stands of yellow sweetclover and black medic. All other legumes failed. Results of a 5-year grazing study on upland, Sandhills range indicated that forage intake of nonsupplemented mature cows in the fall was high at light to moderate-stocking rates (1 to 2 AUM/ha and 40% forage utilization) with dietary crude protein and digestibility above 6% and 53%, respectively. At moderate to high-stocking rates (2 to 3 AUM/ha and 50% utilization), intake declined sharply while diet quality did not differ from those of cattle grazing at lower stocking rates. Vigor and yield of dominant warm-season grasses during growing season were not affected by fall stocking rate whereas yield of cool-season grasses declined in the following growing season as fall stocking rate increased. Increasing density of birdsfoot trefoil in smooth bromegrass pastures did not affect diet selection of grazing cattle. The ratio of smooth bromegrass to
birdsfoot trefoil in the diets was similar regardless of the legume density in mid-May and in late-June. A statewide grazing conference was held and 230 producers and extension, industry and government personnel attended.
Impacts
Reducing winter protein supplementation could improve profitability of spring calving operations by about $30/head. The early weaning work provided timely help to producers for the 2002 drought in the Great Plains. Extending grazing in eastern NE cow-calf systems could improve profit potential from $30 to $50/exposed cow.
Publications
- Anderson, R.V. 2002. An evaluation of cow/calf management strategies to improve economic efficiency. M.S. Thesis. Dept. of Animal Science, University of Nebraska, Lincoln.
- Anderson, R., R. Rasby, T. Klopfenstein, C. Macken. 2002. An evaluation of production efficiency in a cow/calf system designed to add value. J.Anim. Sci. 80(Suppl. 2):110.
- Anderson, RV.., R.J. Rasby, T.J. Klopfenstein, C.N. Macken. 2002. Evaluation of cow and calf performance and profit potential in beef systems. Proc. Western Section, Amer. Soc. Anim. Sci., 53:190.
- Ciminski, Lane Alan. 2002. Fall weaning date and winter protein supplementation effects on cow/calf production. M.S. Thesis. Dept. of Animal Science, Univ. of Nebraska, Lincoln.
- Ciminski, L.A., D.C. Adams, T.J. Klopfenstein, and R.T. Clark. 2002. Effects of weaning date and protein supplementation on cow/calf productivity. Proc. Amer. Soc. Anim. Sci. Midwestern Section., Abstr. 263, P. 65.
- Ciminski, L.A., D.C. Adams, T.J. Klopfenstein, and R.T. Clark. 2002. Weaning date for spring calving cows grazing sandhills range. Proc. Soc. Range Manage. 55th Annual Meeting. Abstr. p. 21.
- Creighton, K.W., J. A. Johnson-Musgrave, D.C. Adams, R.E. Sandberg, J. A. Gosey. 2002. Effects of cow-calf separation on milk production and performance. Proc. Soc. Range Manage. 55th Annual Meeting. Abstr. p. 20. Creighton, K.W., J. A. Hopkin, Amelia M. 2001. Cow-calf-yearling beef production systems in the Nebraska Sandhills. M.S. Thesis. Dept. of Animal Science, Univ. of Nebraska, Lincoln.
- Lamb, J.B., D.C. Adams, T.J. Klopfenstein, R.J. Grant, P.L. Sims, L.M. White, and S.S. Waller. 2002. Intake and digestive kinetics of leaf and stem fractions. J. Range Manage. 55: 57-64.
- Lamothe M.J. 2002. Estimation of microbial and rumen undegradable protein supply in grazing cattle. M.S. Thesis Univ. Nebraska-Lincoln. Lincoln, NE.
- Lamothe M.J., T. Klopfenstein, D Adams, J. Musgrave, and G. Erickson. 2002. Urinary allantoin as estimate of microbial protein synthesis. Proc. Amer. Soc. Anim. Sci. Midwestern Section. P. 60, Abstr. 242.
- Reece, P.E., J.D. Volesky, and W.H. Schacht. 2001. Cover for wildlife after summer grazing on Sandhills rangeland. J. Range Manage. 54:126-131.
- Reece, P.E., J.D. Volesky, and W.H. Schacht. 2001. Integrating management objectives and grazing strategies on semi-arid rangeland. Cooperative Extension, Institute of Agriculture and Natural Resources, University of Nebraks-Lincoln, EC01-158.
- Sprott, L.R., G.E. Selk, and D.C. Adams. 2001. Review: Factors affecting decisions on when to calve beef females. The Professional Animal Scientist17: 238-246.
- Volesky, J.D., D.C. Adams, and R.T. Clark. 2002. Windrow grazing and baled-hay feeding strategies for wintering calves. J. Range Manage. 55:23-32.
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Progress 10/01/00 to 09/30/01
Outputs
Comparison of mid-June to mid-March calving, mature cows has shown at similar weaning age June born calves averaged about 70 pounds less than March born calves and weaning rates were similar for both systems (88%). Net returns from selling June born calves in January were about $70/calf higher than March born calves sold in October. A heifer development trial from both March and June calving herds is nearing completion. Preliminary results: March born heifers developed to 55% of mature body weight at first breeding had higher pregnancy rate (93%) compared to those developed to be 60% (89%) with no statistically significant differences in re-breeding rates. One group of summer born heifers was bred to begin calving about May 15 and another was bred to begin calving June 15. Those bred to calve early had a lower pregnancy rate (88%) compared to those calving later (93%). In another trial spring calving cows were assigned to 2 weaning dates (mid-Aug. and early-Nov.) and
2 protein supplement treatments (none and protein) during winter grazing (Dec.1 to Mar.1) to form 4 production systems. Results indicate that cows fed protein have lower (p<0.01) pregnancy rates (93% vs. 98 %) than those not receiving supplement. Funding has been received to collect sensory and taste panel data from steer carcasses for the value-added and conventional beef systems in eastern Nebraska. Preliminary impacts from a study of interaction effects of summer grazing date and fall stocking rates on Sandhills upland vegetation are: 1) herbage disappearance did not increase proportionately to fall stocking rates and individual animal intake declined rapidly at some point between 1.0 and 2.0 AUM ha-1 stocking rates; 2) herbage disappearance did not differ between 2.0 and 3.0 AUM ha-1 stocking rates; and 3) yields of cool-season graminoids declined the following growing season as fall stocking rates increased. Preliminary results from evaluation of big bluestem response to mid-May
grazing followed by different timings and grazing frequencies through the remainder of the growing season: a mid-May grazing period for big bluestem pasture had no effect on cumulative herbage allowance, increased cumulative herbage disappearance, and increased leaf:stem ratios. Results from systems of feeding weaned calves baled meadow hay or equivalent hay left in windrows: feed cost/head/day were $0.18/head lower for the windrow grazing system; windrow fed calves netted about $50/acre more than bale fed and $86/acre more than selling hay. Alfalfa and birdsfoot trefoil were interseeded into smooth bromegrass pastures at two sites using 5 establishment methods. A trial comparing establishment and persistence of legumes in warm season grass pastures using Birdsfoot trefoil, Illinois bundleflower, and a mixture of red clover, alfalfa, birdsfoot trefoil, Illinois bundleflower sainfoin, and several medics is underway. A statewide grazing conference was held in August. About 250 producers
and extension, industry and government personnel attended.
Impacts
An expected impact of this research is more widespread use of legumes in warm and cool season pastures to improve forage quality and yield and reduce the need for nitrogen especially in cool season pastures. Adoption of change in calving season could improve net income to a cow-calf producer by at least $50/calf. Calving later in the season could improve net returns to over 45,000 head of calves (ranches where changes have already occurred) by at least $25/head for a total improvement of over $1.1 million.
Publications
- Hopkin, A.M., D.C. Adams, T.J. Klopfenstein, and R.T. Clark. 2001. Undegradable intake protein supplementation of March- and June -born steers prevously wintered at two rates of gain. Proc. Amer. Soc. Anim. Sci. Midwest Section March 19-21, 2001. Des Moines, IA. p. 83 (Abstr. 334).
- Jordan, D.J., T.J. Klopfenstein, C.T. Milton, R.J. Cooper, T.L. Scott, G.E. Erickson, and R.T. Clark. 2001. Economic analysis of calf- versus yearling-finishing. Proc. Amer. Soc. Anim. Sci. Midwest Section March 19-21, 2001. Des Moines, IA. p. 23 (Abstr. 94) .
- Jordan, D.J., T.J. Klopfenstein, D.C. Adams, C.T. Milton, R.J. Cooper, D. Downs, and G.E. Erickson. 2001. Effect of winter gain on summer forage intake , summer gain, and finishing performance. Proc. Amer. Soc. Anim. Sci. Midwestern Section March 19-21, 2001. Des Moines, IA. p. 83 (Abstr. 331)
- Mousel, Eric M., Walter H. Schacht, Lowell E. Moser, and Alexander J. Smart. 2001. Summer grazing strategies following early-season grazing big bluestem. In Society for Range Management Abstracts (CD-ROM computer file).SRM, Kailua-Kona, HA. Patterson, H.H., A.M. Hopkin, D.C. Adams, and T.J. Klopfenstein. 2001. Supplementation of lactating two-year-old cows consuming meadow hay to meet metabolizable protein requirements versus degradable intake protein requirements. Proc. Amer. Soc. Anim. Sci. Midwestern Section March 19-21, 2001. Des Moines, IA. p. 83 (Abstr. 336) .
- Herron, Amy E. 2000. Vegetation response to summer by fall grazing interaction effects in the Sandhills. M.S. thesis, Dept. of Agronomy, UNL.
- Jordan, Douglas J. 2000. Performance and slaughter break-even analysis of calf and yearling systems and compensatory growth. PhD Dissertation, Dept. of Animal Science, UNL
- Patterson, Hubert H., III. 2000. Protein supplementation to pregnant heifers and grazing management effects on cow diet quality. PhD Dissertation, Dept. of Animal Science, UNL.
- Richardson, Devon M. 2000. Vegetation response to stocking rate and grazing frequency on sandhills meadows. M.S. Thesis, Dept. of Agronomy, UNL.
- Wilson, Casey. 2000. Undegradeable intake protein supplementation to growing cattle. M.S. Thesis, Dept. of Animal Science, UNL.
- Hoegemeyer, Christian A. 2001. Economic optimization of cattle production with late season calving. M.S. Thesis, Dept. of Agricultural Economics, UNL.
- Mousel, Eric M. 2001. Summer grazing strategies following early-season grazing of big bluestem. M.S. Thesis, Dept. of Agronomy, UNL.
- Adams, D.C., M.K. Nielsen, W.H. Schacht and R.T. Clark. 2000. Designing and conducting experiments for range beef cows. (J. Series No. 12760, ARD, Univ. of NE, Lincoln) Am. Soc. Anim. Sci., 1999. Available at: http://www.asas.org/jas/journal.asp?id=2069&name=University
- Story, C.E., R.J. Rasby, R.T. Clark, and C.T. Milton. 2000. Age of calf at weaning of spring-calving beef cows and the effect on cow and calf performance and production economics. J. Anim. Sci. 78:1403-1413 (J. Series No. 12630, ARD, Univ. of NE, Lincoln)
- Lardy, Gregory, Don C. Adams, Terry J. Klopfenstein, Richard T. Clark and June Emerson. 2001. Escape protein and weaning effects for calves grazing meadow regrowth. J. Range Manage 54:233-238.
- Anderson, Bruce, M.A. Trammell, and T.J. Klopfenstein. 2001. Hybrid and protein supplement affect gains of cattle grazing mature corn. InAgronomy Abstracts (CD-ROM computer file). ASA, Madison, WI.
- Adams, Don, Dick Clark, Russ Sandberg, Gordon Carriker, Terry Klopfenstein, and Todd Milton. 2001. June versus March calving for the Nebraska Sandhills: Production traits. In: 2001 Beef Cattle Report, Ag Research Div., Univ. of NE-Lincoln, MP 76-A. p.8-9.
- Carriker, Gordon, Dick Clark, Don Adams, and Russ Sandberg. 2001. June versus March calving for the Nebraska Sandhills: Economic comparisons. In: 2001 Beef Cattle Report, Ag Research Div., Univ. of NE-Lincoln, MP 76-A. p.10-12.
- Carriker, Gordon, Dick Clark, Don Adams, and Russ Sandberg. 2001. June versus March calving for the Nebraska Sandhills: Economic risk analysis. In: 2001 Beef Cattle Report, Ag Research Div., Univ. of NE-Lincoln, MP 76-A. p.12-14.
- Hopkins, Amelia, Don Adams, Terry Klopfenstein, Todd Milton and Dick Clark. 2001. Protein supplements and performance of cows and calves in June-calving production systems. In: 2001 Beef Cattle Report, Ag Research Div., Univ. of NE-Lincoln, MP 76-A. p.14-16.
- Patterson, Trey, Don Adams, Terry Klopfenstein, Richard Clark, and Burke Teichert. 2001. Performance and economics of winter supplementing pregnant heifers based on the metabolizable protein system. In: 2001 Beef Cattle Report, Ag Research Div., Univ. of NE-Lincoln, MP 76-A. p. 16-19.
- Patterson, Trey, Don Adams, and Terry Klopfenstein. 2001. Forage intake and nutrient balance of heifers grazing Sandhills winter range. In: 2001 Beef Cattle Report, Ag Research Div., Univ. of NE-Lincoln, MP 76-A. p.19-22.
- Patterson, Trey, Terry Klopfenstein, Don Adams, Walter Schacht, Patrick Reece, Jacki Musgrave and Amy Herron. 2001. Summer grazing and fall grazing pressure effects on protein content and digestibility of fall range diets. In: 2001 Beef Cattle Report, Ag Research Div., Univ. of NE-Lincoln, MP 76-A. p.23-25.
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Progress 10/01/99 to 09/30/00
Outputs
An eastern NE study weaned March born calves at three ages,150, 210, and 270 days. Breakeven costs for finished steers favored normal and late weaned calves. Pregnancy rates were not different between treatments, but all cows were fed to a body condition score of 5 or better prior to calving. In the Sandhills, March calving cows were assigned to 2 weaning dates (mid-Aug. and early-Nov.) and 2 protein supplement treatments (none and protein) during winter grazing (Dec.1 to Mar.1) in a 2 x 2 factorial arrangement resulting in 4 production systems. Cows remain in assigned system throughout trial unless culled as open or unhealthy. Preliminary results indicate that cows fed protein have lower pregnancy rates than those not receiving supplement. Protein appears to enhance calf-weaning weights. Production and economic comparisons of a conventional to a value-added beef cattle system for eastern NE is underway. In the conventional system cows remain on pasture to graze, are
supplemented and fed hay in winter and calves are weaned and transported directly to feedlot for finishing. In the value-added system, cows graze grass (spring, summer, fall) and corn stalks (late fall, winter). Calves are weaned and steer calves graze corn stalks, wintered for low gains using forage and grain by-products, graze pasture in spring and summer and are transported to feedlot in fall to be finished by December. A study evaluating effects of spring grazing date and stocking rate on diet composition and utilization of cool-season species and total herbage production was started in the Sandhills. Alternate dormant-season stocking rates (0, 1.0, 2.0, and 3.0 AUM/ha) in Sandhills upland range did not affect etiolated tiller growth of sand bluestem and prairie sandreed the following spring or total yield of above ground herbaceous biomass in June and August of the following year. Higher stocking rates tended to reduce yields of cool-season species and increase warm-season
grasses. A spring grazing study on Sandhill uplands will evaluate effects of stocking rate and date of grazing on plant yield and utilization and botanical and nutrient composition of cattle diets. Response of big bluestem in eastern NE to early-season (mid-May) grazing followed by different timings and frequencies of grazing through the remainder of the growing season is being evaluated. Cumulative disappearance of big bluestem herbage and harvest efficiency was greater in pastures grazed in May than those not grazed until mid-June. Timing and frequency of grazing did not affect basal cover (persistance) of big bluestem. Eight replicates of 3 corn hybrids representing high grain yield, high silage quality, and Grazing Maize were planted in spring, 2000. In September, steers began grazing equal daily strip allotments, and will continue for 90 - 100 d. Steers receive 1 of 4 protein supplements daily. Grain yield and quality as well as animal gains per d and per ha will be measured. A
study to determine defoliation effects on root growth and above-ground production of birdsfoot trefoil, slender wheatgrass, and NE sedge was started in 2000.
Impacts
Potential impacts include improved economic efficiency for producers. This in turn will strengthen local economies as producers have more money to spend on other things. The value of systems research appears to be one of the impacts to the research community. Some of the studies within the project appear to be showing results that are contrary to traditional, component analysis.
Publications
- Story, C.E. 1998. Effects of calf at weaning on spring calving cow and calf performance and production economics. M.S. Thesis. University of Nebraska.
- Story, C.E., R. Rasby, D. Brink, and R. Stock. 1998. Age of calves at weaning effects cow and calf performance and carcass characteristics at slaughter. J. Anim. Sci. 76(Suppl. 1):231.
- Story, C., R. Rasby, T. Milton, and M. Dragastin. 1999. Effects of time of weaning on cow and calf performance. In: 1999 Nebraska Beef Report. ARD, Univ. of NE. Lincoln, MP71-A. p.3-4.
- Sandberg, R.E., D.C. Adams, T.J. Klopfenstein, and R.J. Grant. 2000. N-alkane as an internal marker for predicting digestibility of forages. J. Range Manage. 53:159-163.
- Adams, D.C., and R.T. Clark. 2000. Managing forage resources and extending grazing for efficient beef production. In: proc. Utah Beef Cattle Field Day, Managing Forage Resources for Efficient Beef Production. Utah Cattlemen's Association, Brigham Young Univ. and Utah State Univ. Feb 8, 2000. Provo, UT. p.1-11.
- Rasby, R., C. Story, D. Clark, T. Milton, and M. Dragastin. 2000. Age of calf at weaning of spring-calving beef cows and the effect on production economics. In: '2000 Nebraska Beef Report.' ARD, Univ. of NE. Lincoln, MP73-A. p.3-6.
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