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Full-Text Articles in Life Sciences

Effect Of Ovulatory Follicle Size And Standing Estrus On Circulating Hormone Concentrations And Interval To Ovulation, George A. Perry Feb 2005

Effect Of Ovulatory Follicle Size And Standing Estrus On Circulating Hormone Concentrations And Interval To Ovulation, George A. Perry

South Dakota Beef Report, 2005

In postpartum cows, ovulatory follicle size at time of insemination (GnRH/TAI) influenced pregnancy rates following TAI, but had no effect on pregnancy rates when cows spontaneously ovulated. Furthermore, cows that exhibited estrus (± 24 h of GnRH/TAI) had higher pregnancy rates compared to cows not in estrus. The objective was to assess the relationship between ovulatory follicle size and estradiol concentrations, timing of the LH surge, timing of ovulation, and subsequent progesterone concentrations. Cows were synchronized with the CO-Synch (n = 64; induced ovulation) or the Select Synch (n = 20; spontaneous ovulation) protocol. Cows that exhibited estrus and were …


Effect Of Using Cidrs For Seven Days Before The Introduction Of Bulls On The Proportion Of Cows Conceiving Early In The Breeding Season, George A. Perry Jan 2005

Effect Of Using Cidrs For Seven Days Before The Introduction Of Bulls On The Proportion Of Cows Conceiving Early In The Breeding Season, George A. Perry

South Dakota Beef Report, 2005

Cows that conceive earlier in the breeding season wean calves that are older and heavier at weaning. Therefore, the objective of this study was to determine the ability of a CIDR to increase the proportion of cows that conceived early during a natural service breeding season. Two hundred twenty-two postpartum beef cows were allotted to one of two treatments: 1) cows were treated with a CIDR for 7 days before bulls were introduced (n = 100), 2) cows were not treated and served as a control (n = 122). Seven days before bulls were introduced to the herd CIDRs were …


Comparison Of The Efficiency And Accuracy Of Three Estrous Detection Methods To Indicate Ovulation In Beef Cattle, George A. Perry Jan 2005

Comparison Of The Efficiency And Accuracy Of Three Estrous Detection Methods To Indicate Ovulation In Beef Cattle, George A. Perry

South Dakota Beef Report, 2005

The ability to successfully artificially inseminate cattle requires determining the appropriate time to inseminate. Therefore, detection of standing estrus is a major factor in the success or failure of most artificial insemination programs. The objective of these experiments was to determine the efficiency and accuracy of three estrous detection methods (visual, penile deviated bull, and Estrus Alert estrous detection aids) to determine if animals were going to ovulate. Fifty-three postpartum beef cows were synchronized with an injection of gonadotropin releasing hormone (GnRH) followed by an injection of prostaglandin F2_ (PG) seven days later. Estrus was monitored for 72 hours following …


Spring Drought Effects On Rangeland Forage Yield From Clayey Ecological Sites In Western South Dakota, Alexander J. Smart, Roger N. Gates, Barry H. Dunn Jan 2005

Spring Drought Effects On Rangeland Forage Yield From Clayey Ecological Sites In Western South Dakota, Alexander J. Smart, Roger N. Gates, Barry H. Dunn

South Dakota Beef Report, 2005

Understanding the historical influence of seasonal precipitation, especially spring precipitation, and stocking rate on forage yield would be desirable for planning purposes. The objectives of this study were to examine the historical precipitation pattern and how it influenced forage yield on pastures that were stocked at light, moderate, and heavy stocking rates for 15 years at the Cottonwood Range and Livestock Research Station in western South Dakota. Weather data from 1909 to 2004 at the station were analyzed to determine the frequency of occurrence of below (≤75 of mean), normal, and above normal (>125% of mean) spring precipitation (April, …


Sod Suppression Techniques For Legume Interseeding, Alexander J. Smart, Vance N. Owens, Dick Pruitt Jan 2005

Sod Suppression Techniques For Legume Interseeding, Alexander J. Smart, Vance N. Owens, Dick Pruitt

South Dakota Beef Report, 2005

Sod suppression is necessary for successful establishment of legumes interseeded into existing pasture; however such techniques vary in their effectiveness, cost, and management. Sod suppression experiments for legume interseeding into cool-season pasture were conducted at South Dakota State University’s Cow-Calf Unit located near Brookings, SD in 2003 to 2005. We evaluated (i) spring burn, (ii) field cultivator or disk, (iii) herbicide, (iv) heavy fall and spring graze, and (v) a control with no sod suppression. Legume species were alfalfa, birdsfoot trefoil, and kura clover. Sod suppression techniques enhanced the success of legume interseeding. In this study, the grazing equaled or …


Effect Of Grazing, Mowing, Or Herbicide On Leafy Spurge Control, Kelly W. Bruns, Alexander J. Smart Jan 2005

Effect Of Grazing, Mowing, Or Herbicide On Leafy Spurge Control, Kelly W. Bruns, Alexander J. Smart

South Dakota Beef Report, 2005

Leafy spurge (euphorbia esula L.) is an herbaceous perennial which is deep rooted and can reproduce by seeds and rhizomes. First introduced into North America in the 1800’s from Europe, it now covers 25 states in the USA and several provinces in Canada. It is a major concern in North Dakota, South Dakota, Wyoming, Montana, and Nebraska. Leafy spurge is considered a noxious weed that is extremely competitive, establishing itself in pastureland and roadsides. Bangsund et al. (1997) estimated that by 2005, uncontrolled leafy spurge acres would reach 18.5 million in the Northern Great Plains. The cost of leafy spurge …


Intravenous Ghrelin Infusion Affects Plasma Growth Hormone Concentrations, Dry Matter Disappearance, And Length Of Time Spent Feeding, Aimee E. Wertz-Lutz, Robbi H. Pritchard, Joseph A. Daniel, Jeff A. Clapper Jan 2005

Intravenous Ghrelin Infusion Affects Plasma Growth Hormone Concentrations, Dry Matter Disappearance, And Length Of Time Spent Feeding, Aimee E. Wertz-Lutz, Robbi H. Pritchard, Joseph A. Daniel, Jeff A. Clapper

South Dakota Beef Report, 2005

Six steers (915 ± 37.8 kg) were used in a crossover design to determine the effects of intravenous infusion of bovine ghrelin (BGR) on plasma growth hormone (GH) concentrations, length of time spent feeding, and dry matter disappearance per unit of metabolic weight. Steers were fed individually once daily (0800 h) and allowed to consume ad libitum until 2000 h when feed was removed. Daily feed allotment was sufficient to result in ≥ 10% feed refusal. Serial blood samples were collected from steers fitted with an indwelling jugular catheter at 15-min intervals from 0600 h through 1800 h. Harvested plasma …


Effect Of Feeding Schedule On Tympanic Temperature Of Steer Calves During Winter, Simone M. Holt, Robbi H. Pritchard Jan 2005

Effect Of Feeding Schedule On Tympanic Temperature Of Steer Calves During Winter, Simone M. Holt, Robbi H. Pritchard

South Dakota Beef Report, 2005

Angus steer calves (n=135) were used in a 55d feedlot growing study to investigate the effects of feeding schedule on tympanic temperature response when limit feeding. Steers were fed a high moisture ear corn diet (58 Mcal/cwt NEg) at 0900h (AM), 1500h (PM) or 50% at 0900h and 50% at 1500h (SPLIT) to allow for 2.50lb ADG. Climatic data were collected at 30 min intervals throughout the study via an on site automated weather station. Tympanic temperatures (TT) were collected every 30 min (5 steers/trt) for 5d (d44 to d48). Mean ambient temperature during the 5d TT collection period was …


Effect Of High-Sulfate Water On Trace Mineral Status Of Beef Steers, Cody L. Wright, Hubert H. Patterson Jan 2005

Effect Of High-Sulfate Water On Trace Mineral Status Of Beef Steers, Cody L. Wright, Hubert H. Patterson

South Dakota Beef Report, 2005

Two experiments were conducted to determine the effect of high-sulfate water on the performance, health, and mineral status of growing steers. The first experiment was conducted from June 20 to September 12, 2001, at the South Dakota State University (SDSU) Cottonwood Range and Livestock Research Station. Eighty-one crossbred steers (initial BW = 700 lb) were stratified by weight and randomly assigned to 12 dry-lot pens (6 or 7 steers/pen). Pens were then randomly assigned to one of three water quality treatments: 1) rural water (404 ppm sulfate), 2) well water (3087 ppm sulfate), and 3) stock dam water (3947ppm sulfate). …


Relative Efficiency Of Natural Feeding Programs Using Germ Or Bran Cake From A Dry Milling Process, Robbi H. Pritchard, Donald L. Boggs Jan 2005

Relative Efficiency Of Natural Feeding Programs Using Germ Or Bran Cake From A Dry Milling Process, Robbi H. Pritchard, Donald L. Boggs

South Dakota Beef Report, 2005

This experiment was designed to evaluate the potential of using high-fat ethanol co-products in cattle feeding programs that exclude implants and ionophores. Four treatments included: 1) Positive Control, implanted steers fed a typical diet that included 29g/T monensin; 2) Control Diet fed to non-implanted steers; 3) 14% Germ, no implant or ionophore; and 4) 30% Bran Cake, no implant, no ionophore. After a 110 d finishing period, the breakeven (B/E) fed cattle price increased $3.04/cwt when an implant was not used on the Control diet. The Germ diet resulted in comparable performance as the Control diet fed to non-implanted steers. …


Composition And Nutritive Value Of Corn Fractions And Ethanol Co-Products Resulting From A New Dry-Milling Process, Greg B. Kleinhans, Robbi H. Pritchard, Simone M. Holt Jan 2005

Composition And Nutritive Value Of Corn Fractions And Ethanol Co-Products Resulting From A New Dry-Milling Process, Greg B. Kleinhans, Robbi H. Pritchard, Simone M. Holt

South Dakota Beef Report, 2005

The development of a new dry-milling process for the production of corn ethanol has resulted in new feedstuffs. This process fractionates the corn kernel prior to fermentation. Pre-fermentation fractions include bran, germ, and endosperm. Post-fermentation fractions include dried distillers grains (DDG) and condensed distiller solubles (syrup). Proximate analysis was conducted on these fractions along with the parent corn sample. Equations were used to predict TDN and undegradable intake protein (UIP). These feeds differ substantially from historical dried distiller’s grains with solubles (DDGS). Feeding experiments will be necessary to confirm the results of the predicted feed values.


Corn Germ As A Source Of Supplemental Fat For Cows In Late Gestation, Dick Pruitt, Jeff A. Clapper, William B. Epperson, George A. Perry Jan 2005

Corn Germ As A Source Of Supplemental Fat For Cows In Late Gestation, Dick Pruitt, Jeff A. Clapper, William B. Epperson, George A. Perry

South Dakota Beef Report, 2005

To evaluate corn germ as a source of supplemental fat, 217 two to twelve-year-old cows receiving grass hay free choice were supplemented with either 2.75 lb of corn germ (dry basis) or an equal amount of crude protein from soybean meal (0.80 lb dry matter) starting approximately 50 days prior to the first expected calving. Cows were removed from treatment the day they calved and where managed as a group through the breeding season. Supplement treatment did not affect cow weight change or body condition score. Corn germ did not improve any measure of reproduction, including the percentage of cows …


Effect Of Harvest Method On The Nutrient Composition Of Baled Cornstalks, Cody L. Wright Jan 2005

Effect Of Harvest Method On The Nutrient Composition Of Baled Cornstalks, Cody L. Wright

South Dakota Beef Report, 2005

This experiment was conducted to determine the effect of chopping corn residue prior to baling on the nutrient composition of cornstalk bales. One dryland corn field planted with a single variety of corn was used. After harvest, one half of the field was chopped with a stalk chopper. The remaining half was not chopped. Each half of the field was then raked into windrows, baled, and wrapped with plastic netting. Ten round bales were harvested from each half of the field (chopped and not chopped). Three core samples were then collected from each bale and pooled for analysis. Pooled samples …


Factors Affecting Profitability Of The Cow-Calf Enterprise In The Northern Great Plains, Barry H. Dunn, Dick Pruitt, Edward Hamilton, Duane Griffith Jan 2005

Factors Affecting Profitability Of The Cow-Calf Enterprise In The Northern Great Plains, Barry H. Dunn, Dick Pruitt, Edward Hamilton, Duane Griffith

South Dakota Beef Report, 2005

One hundred and forty eight privately owned and operated cow-calf enterprises were surveyed for their production and financial performance measures and the results analyzed for factors that affected profitability. The results of these analyzes indicate that for cow-calf enterprises in the Northern Great Plains, high levels of profit are a function of lower than average investment, above average reproductive performance, lower than average total expenses, and above average market prices for calves produced. Neither high nor low levels of other biological production, geographical region, size of operation, or year were factors that explained differences in profitability. Profitability measured as Return …


Use Of Corn Co-Products In Soybean Hull-Based Feedlot Receiving Diets, Chad J. Mueller, Donald L. Boggs Jan 2005

Use Of Corn Co-Products In Soybean Hull-Based Feedlot Receiving Diets, Chad J. Mueller, Donald L. Boggs

South Dakota Beef Report, 2005

The use of different supplemental protein sources with soybean hulls in receiving cattle diets were evaluated using 200 Angus steer calves. Diets contained either corn and soybean meal (C-SBM), or soybean hulls with soybean meal (H-SBM), dried corn gluten feed (H-DCGF) or dried distillers grains plus solubles (H-DDGS). The replacement of corn (C-SBM) with soybean hulls (H-SBM) stimulated intake within the first 14 d of the receiving period and throughout the entire growing period (52 d). Supplementing soybean hulls with corn origin protein (COP) versus soybean meal did not result in any performance differences throughout the feeding period. Within the …


Influence Of Calcium Metabolism On Meat Tenderness In Heiferettes, Kelly W. Bruns, Robbi H. Pritchard Jan 2005

Influence Of Calcium Metabolism On Meat Tenderness In Heiferettes, Kelly W. Bruns, Robbi H. Pritchard

South Dakota Beef Report, 2005

Forty beef-type heiferettes (initial BW=1016 ± 93 lb) were used to evaluate the influence of dietary calcium depletion followed by dietary repletion prior to slaughter on carcass and meat quality traits. Treatments were 1.) control - feed calcium diet for duration of trial (13 hd); 2.) calcium depleted 14 days followed by one feeding of replete diet 20 h prior to slaughter (13 hd); 3.) calcium depleted 14 days followed by two feedings of repleted diet 20 h and 44 h before harvest (14 hd). Heifers were sorted on condition and weight from a larger population of 280 head. Heiferettes …


Comparative Anatomy Of A Presorted Pot-Load Of Yearling Steers, Kelly W. Bruns, Robbi H. Pritchard, Simone Holt Jan 2005

Comparative Anatomy Of A Presorted Pot-Load Of Yearling Steers, Kelly W. Bruns, Robbi H. Pritchard, Simone Holt

South Dakota Beef Report, 2005

One load (n = 72; initial BW = 745 ± 54.5) of grass-raised Angus-cross yearling steers was purchased from a sale barn in north central South Dakota. The steers were sorted into load lots by sale barn personnel from a larger group of 1200. Upon arrival, steers were used in the 4-day Feedlot Shortcourse before being weighed and appraised for visual differences. Cattle were divided (randomly) into 8 groups of 9 head each. One steer was randomly selected from each of the eight groups to make a 9th group of steers comprised of each classification. The steers were fed until …


Fenceline Weaning On Pasture And Forage Barley To Extend The Grazing Season For Replacement Heifers - A Three-Year Summary, Dick Pruitt, William Epperson, Vance Owens, Alexander Smart Jan 2005

Fenceline Weaning On Pasture And Forage Barley To Extend The Grazing Season For Replacement Heifers - A Three-Year Summary, Dick Pruitt, William Epperson, Vance Owens, Alexander Smart

South Dakota Beef Report, 2005

In a three-year study at the SDSU Cow/Calf Teaching and Research Unit, Brookings, SD, heifer calves were allotted to two weaning management treatments in early October. The pasture-weaned group was separated from their dams and grazed a grass pasture across the fence from their dams for two weeks. Then, until early December, they grazed “Robust” barley (forage type) that had been no-till planted into oat stubble in early August. The drylot-weaned group was fed a traditional weaning diet of grass hay, corn and protein supplement from weaning until early December. Heifers received the same diet and were managed as one …


Sdsu Cow/Calf Teaching And Research Unit, Dick Pruitt, Kevin Vanderwal, Anna Drew Jan 2005

Sdsu Cow/Calf Teaching And Research Unit, Dick Pruitt, Kevin Vanderwal, Anna Drew

South Dakota Beef Report, 2005

The SDSU Cow/Calf Unit (CCU) provides cattle and facilities for numerous Animal Science and Range Science classes and a variety of research projects. The CCU also provides cattle for the SDSU Little International, Block & Bridle Club activities, numerous judging team workouts, and other activities that bring potential students to the SDSU campus. Kevin VanderWal and Anna Drew along with part-time student employees, manage the herd, collect research data, and assist with numerous beef cattle activities throughout the year.


Evaluation Of Performance And Costs Of Two Heifer Development Systems, Robin R. Salverson, Hubert H. Patterson, George A. Perry, Doug Young, Matt L. Gibson Jan 2005

Evaluation Of Performance And Costs Of Two Heifer Development Systems, Robin R. Salverson, Hubert H. Patterson, George A. Perry, Doug Young, Matt L. Gibson

South Dakota Beef Report, 2005

Early weaned (EW) heifers must be developed for a longer period of time usually resulting in increased development costs. Developing EW heifers on native range may reduce these costs. Dried distillers grains plus solubles (DDGS) offers protein and energy that compliment native forages for developing heifers. The objective of this study was to evaluate the performance and costs of two heifer development systems in northwest South Dakota. Sixty-five nulliparous crossbred beef heifers were randomly allotted to one of two systems: 1) heifers (n=33) weaned at 132 d of age (461 lb) and developed on range with a DDGS supplement (1.8 …


Effects Of Weaning Date And Retained Ownership On Cow And Calf Performance And Forage Disappearance In Spring Calving Beef Systems, Doug G. Landblom, Hubert H. Patterson, Pat Johnson, Roger Gates, Steve Paisley, Doug Young Jan 2005

Effects Of Weaning Date And Retained Ownership On Cow And Calf Performance And Forage Disappearance In Spring Calving Beef Systems, Doug G. Landblom, Hubert H. Patterson, Pat Johnson, Roger Gates, Steve Paisley, Doug Young

South Dakota Beef Report, 2005

Researchers in North Dakota, South Dakota and Wyoming are working together to evaluate the effect of weaning calves 75 days earlier than normal and are following the calves through finishing. This report summarizes accomplishments so far. Briefly, weaning calves 75 days early (mid-August) has improved cow weight and condition score compared to cows whose calves were weaned normally (early-November). Native range forage disappearance has tended to be lower when calves were weaned early. After weaning, backgrounded early weaned steers grew faster and were more efficient. However, early weaned steers required 61 more days on feed to reach final harvest.


Response Of Cow-Calf Pairs To Water High In Sulfates, Hubert Patterson, Pat Johnson, George Perry, Roger Gates, Ron Haigh Jan 2005

Response Of Cow-Calf Pairs To Water High In Sulfates, Hubert Patterson, Pat Johnson, George Perry, Roger Gates, Ron Haigh

South Dakota Beef Report, 2005

Data from our laboratory showed water sulfate levels of 3,000 ppm reduced performance and health of growing steers during summer months. In addition, water averaging 2,600 ppm in sulfates for cow-calf pairs had little impact on calf growth or milk production, but caused small reductions in cow BW and body condition score (BCS). This experiment was conducted to evaluate the effects of high sulfate water on cow and calf performance, milk production, and reproduction. Ninety-six crossbred, lactating cows (ages 2-13; average calving date of April 14) and their calves were assigned, after stratifying by age, weight, and previous winter management, …


Effects Of Feeding Varying Concentrations Of Dry Distiller's Grains With Solubles To Finishing Steers On Feedlot Performance, Nutrient Management And Odorant Emissions, Clint S. Benson, Cody L. Wright, Kent E. Tjardes, Richard E. Nicolai, Bradley D. Rops Jan 2005

Effects Of Feeding Varying Concentrations Of Dry Distiller's Grains With Solubles To Finishing Steers On Feedlot Performance, Nutrient Management And Odorant Emissions, Clint S. Benson, Cody L. Wright, Kent E. Tjardes, Richard E. Nicolai, Bradley D. Rops

South Dakota Beef Report, 2005

A study was conducted to determine the effects of feeding varying concentrations of dried distillers grains with solubles (DDGS) to finishing steers on feedlot performance, nutrient management, and odorant emissions. Prior to initiation of the trial, 192 steers (initial BW = 826 ± 18 lb) were blocked by receiving date, weighed, and randomly allotted to 16 dirt floor pens (48.2 ft x 113.8 ft; 5% slope). Pens were then randomly assigned to one of four dietary treatments. The control diet (CON) contained 82% cracked corn, 10% alfalfa hay, 4% molasses, 3.2% supplement, and 0.8% urea. In the remaining three treatment …


2005 South Dakota Beef Report, Department Of Animal And Range Sciences, South Dakota State University, Agricultural Experiment Station, South Dakota State University, Cooperative Extension Service, South Dakota State University Jan 2005

2005 South Dakota Beef Report, Department Of Animal And Range Sciences, South Dakota State University, Agricultural Experiment Station, South Dakota State University, Cooperative Extension Service, South Dakota State University

South Dakota Beef Report, 2005

This is the 2005 South Dakota Beef Report. The articles published in this report summarize many of the beef cattle research activities conducted at South Dakota State University during 2005. The articles in this report have many levels of application. Some information has immediate application for your farm, ranch, or agribusiness. The articles include information on nutrition, feed management, reproductive management, health, growth and development, and economics of the cattle and beef industry in South Dakota.


Effectiveness Of Dried Distillers Grains With Solubles As A Replacement For Oilseed Meal In Supplements For Cattle Consuming Poor Quality Forage, Heidi Doering-Resch, Cody Wright, Kent Tjardes, George Perry, Kelly Bruns, Bradley Rops Jan 2005

Effectiveness Of Dried Distillers Grains With Solubles As A Replacement For Oilseed Meal In Supplements For Cattle Consuming Poor Quality Forage, Heidi Doering-Resch, Cody Wright, Kent Tjardes, George Perry, Kelly Bruns, Bradley Rops

South Dakota Beef Report, 2005

A two-year study was conducted at the South Dakota State University Southeast Research Farm in Beresford, SD, to determine the effects of feeding supplemental dried distillers grains with solubles (DDGS) on the performance of mid-gestation and non-gestating, non-lactating beef cows. Ninety-six gestating beef cows (initial BW = 1276.4 ± 22.2; initial BCS = 4.7 ± 0.09) and 96 non-gestating, non-lactating beef cows (initial BW = 1214.0 ± 20.8; initial BCS = 5.4 ± 0.10) were used for year 1 and year 2, respectively. Cows were stratified by weight and allocated to one of 15 pens. Pens were then randomly assigned …


Evaluation Of Dried Distillers Grains With Solubles As A Feedstuff For Heifers In The Last Trimester Fo Gestation, Chanda L. Engel, Hubert H. Patterson, George A. Perry, Ron Haigh, Jason Johnson Jan 2005

Evaluation Of Dried Distillers Grains With Solubles As A Feedstuff For Heifers In The Last Trimester Fo Gestation, Chanda L. Engel, Hubert H. Patterson, George A. Perry, Ron Haigh, Jason Johnson

South Dakota Beef Report, 2005

Ninety-six crossbred heifers were used in an experiment to evaluate the effect of dried distillers grains plus solubles (DDGS), fed in the last trimester of gestation, on heifer performance and reproduction. Animals were blocked by previous heifer development strategy (Antelope Research Station range developed = ANT 1; Antelope Research Station dry lot developed = ANT 2; Cottonwood research station = CTW), stratified by expected calving date, body weight and body condition score, and randomly allotted to one of twelve pens. Each pen was randomly assigned to one of two treatments (6 pens/treatment; 4 pens per block). Treatments were 1) dried …


Forecasting Forage Yield On Clayey Ecological Sites In Western South Dakota Using Weather Data, Alexander J. Smart, Barry H. Dunn, Lan Xu, Patricia S. Johnson, Roger N. Gates Jan 2005

Forecasting Forage Yield On Clayey Ecological Sites In Western South Dakota Using Weather Data, Alexander J. Smart, Barry H. Dunn, Lan Xu, Patricia S. Johnson, Roger N. Gates

South Dakota Beef Report, 2005

The ability to forecast annual forage yield from weather data would be useful for making appropriate adjustments to stocking rates in order to achieve or maintain desired plant communities. Our objective was to determine the relationship between weather variables and annual forage yield from three distinct plant communities on clayey ecological sites in western South Dakota. Forage yield and weather data were collected from 1945 through 1960 at the Cottonwood Range and Livestock Research Station, in western South Dakota. Pastures stocked at 0.25, 0.40, and 0.60 AUM/acre from 1942 to 1960 developed into western wheatgrass-dominated, western wheatgrass-shortgrass co-dominated, and shortgrass …