+publisher:"Virginia Tech" +contributor:("McCann, Mark A.")

Virginia Tech

1. Bauer, Robert Benjamin. Mob stocking effects on herbage nutritive value, herbage accumulation, and plant species composition.

Degree: MS, Crop and Soil Environmental Sciences, 2015, Virginia Tech

URL: http://hdl.handle.net/10919/73914

► Mob stocking is a variation of rotational stocking known for restricting a large number of animals to a small area before being moved to new… (more)

▼ Mob stocking is a variation of rotational stocking known for restricting a large number of animals to a small area before being moved to new grass after a few hours. This method allows a long (90-day) recovery period but was hypothesized to diminish the nutritional value of herbage relative to continuous and rotational stocking with lesser stocking density at similar stocking rates. This thesis summarizes two studies conducted in Blacksburg and Raphine, and in Steeles Tavern, VA, respectively, at a single beef cattle stocking rate of 12 animal unit months per hectare live body weight. The objectives were to: (1) compare the yield and nutritional value of herbage in pastures managed with three stocking methods, termed mob, rotational, and continuous stocking; (2) compare the abundance of seeded clover species among the stocking methods; and (3) estimate the nutritional value of herbage that is consumed by beef cattle during mob stocking using extrusa sampled from esophageally-cannulated animals. Analysis of standing herbage during two years produced several important findings. Although standing herbage mass was significantly greater in mob stocked pastures at Blacksburg and Raphine, aboveground net primary productivity in 2014 did not differ significantly among mob, rotational, and continuous stocking at any of the project locations. Herbage nutritive value did not differ significantly among stocking methods over two years at Blacksburg and Raphine; however, herbage from mob stocked pastures at Steeles Tavern contained significantly greater concentrations of crude protein in September and October relative to herbage from continuous- and rotationally-stocked pastures at those times. Differences in herbage mass likely contributed to significant differences in establishment of seeded clovers: red clover [Trifolium pratense L. Cinnamon Plus] establishment was similar among stocking methods but white clover [Trifolium repens L. Will] establishment was greater in continuously stocked pastures than mob and rotationally stocked pastures. Hand-clipped samples collected at Blacksburg in September 2014 significantly underestimated the crude protein content of the herbage selected by the steers, although the concentrations of fiber constituents in herbage did not differ significantly between clipped samples and esophageal samples. Although the nutritive value of the herbage on offer did not generally differ among stocking methods at this stocking rate, diet selected was at times less nutritious during mob stocking than continuous and rotational stocking methods. At this stocking rate, stocking method had less influence on pastures than seasonal variation in weather and plant maturity. Advisors/Committee Members: Tracy, Benjamin F. (committeechair), Fike, John Herschel (committee member), McCann, Mark A. (committee member).

Subjects/Keywords: Mob stocking; forage nutritive value; clover; esophageal cannulation

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APA (6^th Edition):

Bauer, R. B. (2015). Mob stocking effects on herbage nutritive value, herbage accumulation, and plant species composition. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/73914

Chicago Manual of Style (16^th Edition):

Bauer, Robert Benjamin. “Mob stocking effects on herbage nutritive value, herbage accumulation, and plant species composition.” 2015. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/73914.

MLA Handbook (7^th Edition):

Bauer, Robert Benjamin. “Mob stocking effects on herbage nutritive value, herbage accumulation, and plant species composition.” 2015. Web. 18 Jan 2021.

Vancouver:

Bauer RB. Mob stocking effects on herbage nutritive value, herbage accumulation, and plant species composition. [Internet] [Masters thesis]. Virginia Tech; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/73914.

Council of Science Editors:

Bauer RB. Mob stocking effects on herbage nutritive value, herbage accumulation, and plant species composition. [Masters Thesis]. Virginia Tech; 2015. Available from: http://hdl.handle.net/10919/73914

Virginia Tech

2. Riley, Elizabeth. Fecal Phosphorus Characteristics of Forage-Fed Beef Cattle.

Degree: MS, Animal and Poultry Sciences, 2013, Virginia Tech

URL: http://hdl.handle.net/10919/23230

► Phosphorus loads in waterways are a focus of environmental concern. Animal agriculture\'s contribution to this problem has been documented and efforts are focused on mitigating… (more)

Subjects/Keywords: phosphorus; beef cattle; forage

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APA (6^th Edition):

Riley, E. (2013). Fecal Phosphorus Characteristics of Forage-Fed Beef Cattle. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/23230

Chicago Manual of Style (16^th Edition):

Riley, Elizabeth. “Fecal Phosphorus Characteristics of Forage-Fed Beef Cattle.” 2013. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/23230.

MLA Handbook (7^th Edition):

Riley, Elizabeth. “Fecal Phosphorus Characteristics of Forage-Fed Beef Cattle.” 2013. Web. 18 Jan 2021.

Vancouver:

Riley E. Fecal Phosphorus Characteristics of Forage-Fed Beef Cattle. [Internet] [Masters thesis]. Virginia Tech; 2013. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/23230.

Council of Science Editors:

Riley E. Fecal Phosphorus Characteristics of Forage-Fed Beef Cattle. [Masters Thesis]. Virginia Tech; 2013. Available from: http://hdl.handle.net/10919/23230

Virginia Tech

3. Shireman, Nathan Todd. Forage Utilization and Nitrogen Management of Tall Fescue Stockpiled for Winter Grazing.

Degree: MS, Animal and Poultry Sciences, 2015, Virginia Tech

URL: http://hdl.handle.net/10919/53959

► The Southeastern United States offers a beneficial environment for stocker and cow-calf production. Abundant tall fescue grass offers a feed source that has been underutilized.… (more)

Subjects/Keywords: tall fescue; cattle; grazing; forage; stockpiling

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APA (6^th Edition):

Shireman, N. T. (2015). Forage Utilization and Nitrogen Management of Tall Fescue Stockpiled for Winter Grazing. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/53959

Chicago Manual of Style (16^th Edition):

Shireman, Nathan Todd. “Forage Utilization and Nitrogen Management of Tall Fescue Stockpiled for Winter Grazing.” 2015. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/53959.

MLA Handbook (7^th Edition):

Shireman, Nathan Todd. “Forage Utilization and Nitrogen Management of Tall Fescue Stockpiled for Winter Grazing.” 2015. Web. 18 Jan 2021.

Vancouver:

Shireman NT. Forage Utilization and Nitrogen Management of Tall Fescue Stockpiled for Winter Grazing. [Internet] [Masters thesis]. Virginia Tech; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/53959.

Council of Science Editors:

Shireman NT. Forage Utilization and Nitrogen Management of Tall Fescue Stockpiled for Winter Grazing. [Masters Thesis]. Virginia Tech; 2015. Available from: http://hdl.handle.net/10919/53959

Virginia Tech

4. Schlueter, David Henry. Overseeding Clovers into Permanent Pastures.

Degree: MS, Crop and Soil Environmental Sciences, 2011, Virginia Tech

URL: http://hdl.handle.net/10919/34719

► Benefits of establishing legumes into permanent pastures have been well studied. Successful establishment of legumes in pastures can be challenging, however, and more information is… (more)

▼ Benefits of establishing legumes into permanent pastures have been well studied. Successful establishment of legumes in pastures can be challenging, however, and more information is needed about different seeding methods and variables that affect legume establishment. A pasture and a small plot experiment were conducted in Blacksburg, Va from 2009 to 2011to gain better understanding of how seeding method and management variables affected red clover (Trifolium pratense L.) and white clover (Trifolium repens L.) establishment into permanent cool season grass pasture and sod. In the pasture experiment, seedling density was measured two months after sowing and grass, white clover, red clover, and weed biomass were periodically measured during the experiment. Broadcast seeding treatment had 93% more clover seedlings than drill treatment (P = 0.1087) two months after sowing. No difference (P > 0.10) for clover biomass was observed between sowing treatments in any year and clover establishment was considered successful (over 25% of pasture composition) in both treatments. In the drill treatment, clover seedling density was negatively affected by the residual grass biomass at sowing (P = 0.0196). In the broadcast treatment, a quadratic relationship between clover seedling density and residual grass biomass at sowing was found (P = 0.0516). Clover seedling density in April 2009 determined the amount of clover biomass in August 2009 (P = 0.0008) and the 2010 clover biomass mean (P = 0.0249). Further exploration of the influence fertilization with P and K, grass biomass at sowing, and defoliation frequency on clover establishment were studied in a split-split plot study. iii Fertilization with P and K was assigned to whole plots that were split in half and assigned a high or low grass biomass at sowing treatment, the subplots were split in and designated either a high or low cutting frequency. Prior to cutting, samples from each plot were sorted to grass, white clover, red clover, and weed. Plots with a low grass biomass at sowing (232 seedlings m-2) had a higher seedling density (P < 0.0001) compared with plots with a high grass biomass at sowing plots (111 seedlings m-2). Greater biomass of white and red clover depended both on having a low grass biomass at sowing and a high frequency of defoliation (P = 0.0026 and P < 0.0001, respectively). Red clover yield was also determined by interactions between fertilization and a high frequency of defoliation (P < 0.0001), as well as between fertilization and low grass biomass at sowing (P = 0.0026). Dry conditions resulted in low clover yields (6% of total herbage mass) with red clover producing four times the herbage mass of white clover. These data show that creating a favorable environment for seedlings to germinate and establish was more important than seeding method. Advisors/Committee Members: Tracy, Benjamin F. (committeechair), Abaye, Azenegashe Ozzie (committee member), McCann, Mark A. (committee member).

Subjects/Keywords: cutting frequency; grass competition; clover; fertility; sowing method; overseeding

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APA (6^th Edition):

Schlueter, D. H. (2011). Overseeding Clovers into Permanent Pastures. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/34719

Chicago Manual of Style (16^th Edition):

Schlueter, David Henry. “Overseeding Clovers into Permanent Pastures.” 2011. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/34719.

MLA Handbook (7^th Edition):

Schlueter, David Henry. “Overseeding Clovers into Permanent Pastures.” 2011. Web. 18 Jan 2021.

Vancouver:

Schlueter DH. Overseeding Clovers into Permanent Pastures. [Internet] [Masters thesis]. Virginia Tech; 2011. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/34719.

Council of Science Editors:

Schlueter DH. Overseeding Clovers into Permanent Pastures. [Masters Thesis]. Virginia Tech; 2011. Available from: http://hdl.handle.net/10919/34719

Virginia Tech

5. Vargas Jurado, Napoleon. Assessing the reliability of plant-wax markers to delineate diet choice and feed efficiency in beef heifers.

Degree: MS, Animal and Poultry Sciences, 2012, Virginia Tech

URL: http://hdl.handle.net/10919/34299

► Estimating feed efficiency in grazing environments is challenging due to difficulties in quantifying food intakes and diet choices in free-grazing animals. The plant-wax marker technique… (more)

Subjects/Keywords: feed efficiency; diet choice; Beef cattle; grazing; plant-wax markers

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vargas Jurado, N. (2012). Assessing the reliability of plant-wax markers to delineate diet choice and feed efficiency in beef heifers. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/34299

Chicago Manual of Style (16^th Edition):

Vargas Jurado, Napoleon. “Assessing the reliability of plant-wax markers to delineate diet choice and feed efficiency in beef heifers.” 2012. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/34299.

MLA Handbook (7^th Edition):

Vargas Jurado, Napoleon. “Assessing the reliability of plant-wax markers to delineate diet choice and feed efficiency in beef heifers.” 2012. Web. 18 Jan 2021.

Vancouver:

Vargas Jurado N. Assessing the reliability of plant-wax markers to delineate diet choice and feed efficiency in beef heifers. [Internet] [Masters thesis]. Virginia Tech; 2012. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/34299.

Council of Science Editors:

Vargas Jurado N. Assessing the reliability of plant-wax markers to delineate diet choice and feed efficiency in beef heifers. [Masters Thesis]. Virginia Tech; 2012. Available from: http://hdl.handle.net/10919/34299

6. Harmon, Deidre Danielle. Phosphorus excretion in beef steers as impacted by increasing levels of corn gluten feed.

Degree: MS, Animal and Poultry Sciences, 2014, Virginia Tech

URL: http://hdl.handle.net/10919/50510

► Overfeeding of phosphorus (P) is a contributing factor to P levels in surface waters. The objective of this study was to determine the impact of… (more)

▼ Overfeeding of phosphorus (P) is a contributing factor to P levels in surface waters. The objective of this study was to determine the impact of increasing levels of corn gluten feed (CGF) as a supplemental source of P on fecal P excretions. Eight Hereford steers (427±79 kg) were randomly assigned to one of four dietary treatments in a 4 x 4 replicated Latin square design. Steers were fed chopped grass hay ad libitum (0.13% P) and 0, 0.5, 1.0 or 1.5 kg/d of dried CGF pellets. All steers were supplemented with 0.91 kg/d beet pulp, 0.34 kg/d rumen-inert fat supplement and 18.14 g/d trace mineral salt. Urea was added to the respective diets at levels of 95.25, 72.57, 49.90, and 31.75 g/d to ensure equal dietary protein across treatments. Steers were housed individually and fitted with total fecal collection bags. Steers were adjusted to each diet for 9-d followed by a 5-d collection period. Following the final collection of each period, a 10 ml jugular blood sample was collected and analyzed to determine serum inorganic P. Dietary total P increased (P < 0.05) as CGF level increased: 8.72, 12.59, 16.75 and 20.88 g/d. Dry matter digestibility increased linearly (P < 0.05) as dietary P increased: 50.35, 53.66, 54.25 and 55.42%. Total P excretion increased linearly (P < 0.05) with increasing CGF level: 9.66, 11.71, 14.29, 16.96 g/day. Inorganic P excretion increased linearly (P < 0.05) with increasing CGF level: 4.11, 5.93, 8.36 and 9.92 g/day. Total P excretion was highly related (P < 0.05; r2 = 0.79) to inorganic P excretion. Serum inorganic P increased linearly (P < 0.05) with increasing dietary P content: 5.61, 5.87, 6.64 and 6.80 mg/dL. Fecal P increased as CGF level increased in steers fed varying dietary levels of P from plant sources. Management of P intake can be a strategic practice to reduce P fecal excretions in beef cattle. Advisors/Committee Members: McCann, Mark A. (committeechair), El-Kadi, Samer Wassim (committee member), Hanigan, Mark Daniel (committee member).

Subjects/Keywords: Beef Cattle; Phosphorus; Fecal Excretions

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APA (6^th Edition):

Harmon, D. D. (2014). Phosphorus excretion in beef steers as impacted by increasing levels of corn gluten feed. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/50510

Chicago Manual of Style (16^th Edition):

Harmon, Deidre Danielle. “Phosphorus excretion in beef steers as impacted by increasing levels of corn gluten feed.” 2014. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/50510.

MLA Handbook (7^th Edition):

Harmon, Deidre Danielle. “Phosphorus excretion in beef steers as impacted by increasing levels of corn gluten feed.” 2014. Web. 18 Jan 2021.

Vancouver:

Harmon DD. Phosphorus excretion in beef steers as impacted by increasing levels of corn gluten feed. [Internet] [Masters thesis]. Virginia Tech; 2014. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/50510.

Council of Science Editors:

Harmon DD. Phosphorus excretion in beef steers as impacted by increasing levels of corn gluten feed. [Masters Thesis]. Virginia Tech; 2014. Available from: http://hdl.handle.net/10919/50510

Virginia Tech

7. Hurder, Katherine Anne. Nitrogen Rate and Source Effects on Biomass Yield of Teff Grown for Livestock Feed in the Mid-Atlantic Region.

Degree: MSin Life Sciences, Crop and Soil Environmental Sciences, 2011, Virginia Tech

URL: http://hdl.handle.net/10919/32159

► Teff (Erogrostis tef (Zucc.)), an annual warm-season grass from Ethiopia, has potential to provide forage during periods when cool-season grass growth is limited by high… (more)

Subjects/Keywords: nitrogen; poultry litter; forage; nitrates; teff

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APA (6^th Edition):

Hurder, K. A. (2011). Nitrogen Rate and Source Effects on Biomass Yield of Teff Grown for Livestock Feed in the Mid-Atlantic Region. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/32159

Chicago Manual of Style (16^th Edition):

Hurder, Katherine Anne. “Nitrogen Rate and Source Effects on Biomass Yield of Teff Grown for Livestock Feed in the Mid-Atlantic Region.” 2011. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/32159.

MLA Handbook (7^th Edition):

Hurder, Katherine Anne. “Nitrogen Rate and Source Effects on Biomass Yield of Teff Grown for Livestock Feed in the Mid-Atlantic Region.” 2011. Web. 18 Jan 2021.

Vancouver:

Hurder KA. Nitrogen Rate and Source Effects on Biomass Yield of Teff Grown for Livestock Feed in the Mid-Atlantic Region. [Internet] [Masters thesis]. Virginia Tech; 2011. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/32159.

Council of Science Editors:

Hurder KA. Nitrogen Rate and Source Effects on Biomass Yield of Teff Grown for Livestock Feed in the Mid-Atlantic Region. [Masters Thesis]. Virginia Tech; 2011. Available from: http://hdl.handle.net/10919/32159

8. Neil, Scott Joseph. Effects of Phosphorus Supplementation on Grazing Beef Cattle.

Degree: MS, Animal and Poultry Sciences, 2015, Virginia Tech

URL: http://hdl.handle.net/10919/63922

► Phosphorus (P) losses due to overfeeding of the mineral to livestock can contribute to surface water degradation. The objective of this study was to examine… (more)

▼ Phosphorus (P) losses due to overfeeding of the mineral to livestock can contribute to surface water degradation. The objective of this study was to examine the impact to supplementing various levels of mineral P to grazing beef cattle. A producer survey and a research trial were conducted to examine the effects of supplementing mineral phosphorus (P) to grazing cattle. In the first study, mineral tags, producer surveys, and fecal, forage, and soil samples were collected from beef cattle operations in Virginia's Chesapeake Bay watershed. Samples (n=166) were collected from 120 producers in 11 counties. Soil test P results were based on Virginia Cooperative Extension soil test guidelines characterized as low (12 %), medium (37 %), high (35 %), and very high (16 %). Pasture grab samples contained 0.34 ± 0.12% P and forage P concentration increased (P < 0.01) across soil P categories going from low to very high. Fecal total phosphorus (TP) was lowly correlated (R2 = 0.18, P < 0.01) to forage P concentration. Mineral supplements were categorized as nil (<1.0% P), low (1.0-<3.0% P), medium (3.0-<6.0% P), and high (>6.0% P). Fecal TP and inorganic phosphorus (Pi) concentration increased (P < 0.01) with mineral P levels. Fecal TP and Pi were lower (P < 0.01) when nil and low P mineral were supplemented as compared to medium and high P mineral. Soluble P (defined as fecal Pi/fecal TP*100) also increased (P < 0.01) with increasing mineral P content going from nil to high. All farms surveyed required little or no P supplementation in regard to beef cattle P requirements. The majority (82%) of producers were receptive to modifying mineral P supplementation practices based on forage P levels. A 56-d study was also conducted with eight yearling Hereford steers (261±30 kg) grazing cool-season grass fall re-growth to determine the effects of varying levels of P supplementation on fecal P excretion. Treatments consisted of dicalcium phosphate supplemented at 0 (D1), 10.0 (D2), 20.0 (D3), or 30.0 (D4) g/d in a randomized 4x4 replicated Latin square design. These treatments provided an additional 0, 1.9, 3.7, and 5.6 g/d of P respectively. Two esophageally cannulated steers were used to collect forage samples for nutrient analysis. Forage P content was analyzed from hand collected samples. Forage P concentrations averaged 0.49% of dry matter (DM) across all periods. Chromic oxide (Cr2O3) was administered twice daily via gelatin capsule at 0630 and 1830 to serve as an external marker for determination of fecal dry matter excretion (DME). Indigestible NDF (iNDF) was used as an internal marker to determine dry matter intake (DMI). Due to the high forage P content, average P intake was in excess of National Research Council (NRC) requirements for all diets (D1 = 281%; D2 = 297%; D3 = 323%; D4 =348%). Orthogonal contrasts were performed to assess the relationship between treatment and P excretion. A linear response (P < 0.01) in daily inorganic P (Pi) excretion (0.054, 0.052, 0.062 and 0.063 g/kg of BW ± 0.003 for D1, D2, D3 and D4,… Advisors/Committee Members: McCann, Mark A. (committeechair), Maguire, Rory Owen (committee member), El-Kadi, Samer Wassim (committee member), Hanigan, Mark Daniel (committee member).

Subjects/Keywords: phosphorus; beef cattle; grazing

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APA (6^th Edition):

Neil, S. J. (2015). Effects of Phosphorus Supplementation on Grazing Beef Cattle. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/63922

Chicago Manual of Style (16^th Edition):

Neil, Scott Joseph. “Effects of Phosphorus Supplementation on Grazing Beef Cattle.” 2015. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/63922.

MLA Handbook (7^th Edition):

Neil, Scott Joseph. “Effects of Phosphorus Supplementation on Grazing Beef Cattle.” 2015. Web. 18 Jan 2021.

Vancouver:

Neil SJ. Effects of Phosphorus Supplementation on Grazing Beef Cattle. [Internet] [Masters thesis]. Virginia Tech; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/63922.

Council of Science Editors:

Neil SJ. Effects of Phosphorus Supplementation on Grazing Beef Cattle. [Masters Thesis]. Virginia Tech; 2015. Available from: http://hdl.handle.net/10919/63922

Virginia Tech

9. Ghimire, Sandip. Volatile Fatty Acid Production in Ruminants.

Degree: PhD, Animal Sciences, Dairy, 2015, Virginia Tech

URL: http://hdl.handle.net/10919/75306

► Volatile fatty acids (VFA) are important products of ruminal fermentation. The VFA are not only the major source of energy to the ruminant animals but… (more)

▼ Volatile fatty acids (VFA) are important products of ruminal fermentation. The VFA are not only the major source of energy to the ruminant animals but also influence methane production in the rumen. Therefore it is important to understand mechanism controlling VFA production and to depict VFA production in a model. This will allow us to devise strategies to enhance energy utilization and reduce methane production in ruminant livestock. An evaluation of a mechanistic model in predicting VFA production was conducted and equations were introduced into the model to improve the predictions. Later a continuous culture experiment was conducted to test the hypothesis on which those equations were based on. A mechanistic model -" Molly, was evaluated using a dataset with reported VFA production rates. The results of residual error analysis indicated that the root mean square prediction errors (RMSPE) were 63, 63, and 49% for acetate, propionate and butyrate, respectively. An assessment from two studies reporting VFA production revealed a potential of reducing errors of prediction by representing interconversion among VFA. In the second study, equations based on thermodynamics influence of pH and VFA concentration were introduced in the model to represent interconversion among VFA. The parameters for de novo VFA production and VFA absorption were re derived with (VFAInt) and without (BASE) the new interconversion equations. There were some improvements in the VFA concentration predictions but the improvements were both in VFAInt and BASE models. The RMSPE of VFA production were still above 50% for acetate, propionate and butyrate. The larger errors of predictions were attributed to measurement variation in VFA production literature, or possible incorrect rate constants for interconversion equations. Finally, a third study was conducted to assess the effect of pH, and VFA concentration on VFA and methane production in continuous culture. The treatments consisted of control, 20 mmol/d acetate infusion (INFAC), 7 mmol/d propionate infusion (INFPR), and low pH (LOWPH). Individual isotopes of acetate, propionate and butyrate were infused in the fermenters to estimate interconversions among VFA. With LOWPH treatment methane emission was reduced whereas production of propionate was increased. Hydrogen production was higher in INFAC indicating that some of the acetate could have been degraded to CO2 and H2. It was estimated that around 3 % of de novo acetate was converted to propionate and 9 % to butyrate. Exchange between propionate and butyrate was insignificant and below 1% of de novo production of either VFA. However, treatments did not affect interconversion rates among VFA. These results indicated that pH and VFA concentration do not have thermodynamic influence on VFA interconversion as hypothesized. Advisors/Committee Members: Hanigan, Mark Daniel (committeechair), Akers, Robert Michael (committee member), Ogejo, Jactone Arogo (committee member), McCann, Mark A. (committee member), Escobar Monestel, Jeffery E. (committee member).

Subjects/Keywords: volatile fatty acids; rumen; methane; thermodynamics

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APA (6^th Edition):

Ghimire, S. (2015). Volatile Fatty Acid Production in Ruminants. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/75306

Chicago Manual of Style (16^th Edition):

Ghimire, Sandip. “Volatile Fatty Acid Production in Ruminants.” 2015. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/75306.

MLA Handbook (7^th Edition):

Ghimire, Sandip. “Volatile Fatty Acid Production in Ruminants.” 2015. Web. 18 Jan 2021.

Vancouver:

Ghimire S. Volatile Fatty Acid Production in Ruminants. [Internet] [Doctoral dissertation]. Virginia Tech; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/75306.

Council of Science Editors:

Ghimire S. Volatile Fatty Acid Production in Ruminants. [Doctoral Dissertation]. Virginia Tech; 2015. Available from: http://hdl.handle.net/10919/75306

Virginia Tech

10. Emenheiser, Joseph Carl. Economic Pasture-Based Cow-Calf Systems for Appalachia.

Degree: PhD, Animal and Poultry Sciences, 2014, Virginia Tech

URL: http://hdl.handle.net/10919/24787

► Pasture-based beef production is well-suited for the Appalachian region of the United States. This research investigated pasture, beef cattle, and economics components within the cow-calf… (more)

▼ Pasture-based beef production is well-suited for the Appalachian region of the United States. This research investigated pasture, beef cattle, and economics components within the cow-calf sector of pasture beef production, and presents implications of their interplay for the vitality of the whole system. Samples of forage DM mass and CP, ADF, NDF, and ash contents in each paddock of a rotational stocking system were collected monthly for 4 grazing seasons. Effects of month, stockpiling, hay feeding, temperature, precipitation, and durations of paddock grazing and rest on forage mass and quality measurements were investigated. The system was complex and dynamic; precipitation and rest days in particular showed clear interactions with both month and stockpiling when predicting forage mass and quality. Available DM, TDN, and CP were compared to nutrient density requirements for beef cows to conclude that the system met or exceeded requirements. Six years of production data from a spring-calving cow-calf enterprise that utilized rotational stocking and fall stockpiling were analyzed. Comparisons among 2 cow frame size and 2 calf creep system treatments for production efficiency (total weaning weight per land area), and net returns to the enterprise, were made. Pastures with medium frame cows and designated creep systems had the greatest production efficiency, but also had the highest costs and netted the least returns. Greatest net returns were achieved in large frame, forward creep systems, which had the lowest production efficiency but also the lowest costs. Provided the quality of calves produced is suitable for other phases of the production stream, we conclude that minimizing costs rather than maximizing productive outputs is a better focus for cow-calf enterprises faced with similar decisions among frame size and creep system treatments. Advisors/Committee Members: Lewis, Ronald M. (committeechair), Greiner, Scott P. (committee member), Tracy, Benjamin F. (committee member), McCann, Mark A. (committee member), Groover, Gordon E. (committee member), D'Souza, Gerard E. (committee member).

Subjects/Keywords: Appalachia; beef; cow-calf; economics; forage dynamics; production

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APA (6^th Edition):

Emenheiser, J. C. (2014). Economic Pasture-Based Cow-Calf Systems for Appalachia. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/24787

Chicago Manual of Style (16^th Edition):

Emenheiser, Joseph Carl. “Economic Pasture-Based Cow-Calf Systems for Appalachia.” 2014. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/24787.

MLA Handbook (7^th Edition):

Emenheiser, Joseph Carl. “Economic Pasture-Based Cow-Calf Systems for Appalachia.” 2014. Web. 18 Jan 2021.

Vancouver:

Emenheiser JC. Economic Pasture-Based Cow-Calf Systems for Appalachia. [Internet] [Doctoral dissertation]. Virginia Tech; 2014. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/24787.

Council of Science Editors:

Emenheiser JC. Economic Pasture-Based Cow-Calf Systems for Appalachia. [Doctoral Dissertation]. Virginia Tech; 2014. Available from: http://hdl.handle.net/10919/24787

Virginia Tech

11. Wettathperuma Arachchige, Deepthi Nayananjalie. Effect of early grain feeding of steers on postabsorptive capacity to utilize acetate and glucose.

Degree: PhD, Animal Sciences, Dairy, 2012, Virginia Tech

URL: http://hdl.handle.net/10919/49566

► The aims of the first study were to determine the effects of early weaning followed by a period of high-grain feeding on signaling protein phosphorylation… (more)

▼ The aims of the first study were to determine the effects of early weaning followed by a period of high-grain feeding on signaling protein phosphorylation in muscle and on acetate clearance in growing steers. Twelve Angus X Simmental steers were used in the study. Six steers were weaned early (EW) and fed a high-gain diet for 148 d and the remainder were weaned at the normal age (NW). Longissimus muscle tissue biopsies were collected to determine total and phosphorylated forms of AMP kinase and downstream proteins of the mTOR signaling pathway. Of the 12, 8 steers were used to assess acetate clearance at different age points. During early grain feeding, phosphorylated:total ratios of rpS6 and S6K1 were greater in EW steers and they had lower acetate clearance rates and greater synthesis rates. The objectives of second study were to assess the effects of early grain feeding on acetate and glucose turnover rates, palmitate synthesis, and on acetate and glucose preference by subcutaneous, intramuscular and visceral adipose tissues in finishing steers. Sixteen Angus x Simmental steers were infused continuously with [2H3] acetate (n = 8) or [U-13C6] glucose (n = 8), over a 12 h period immediately prior to harvest. Plasma acetate and glucose enrichment, and palmitate enrichment in different adipose tissue locations were determined. There were no treatment effects on acetate or glucose turnover rates or palmitate fractional synthesis rates (FSR). Acetate turnover and palmitate FSR from acetate were greater than the corresponding rates from glucose. There were no differences in preference for acetate or glucose among the fat depots. In conclusion, phosphorylation ratios of signaling proteins were not affected treatment. Acetate clearance increased when steers were heavier and older. Thus older calves are able to clear more acetate per unit of time and body mass than younger calves reflective of an enhanced ability to utilize the substrate. There were no differences in preference for acetate and glucose among the major fat depots. Thus diets leading to high glucose supply will not preferentially direct energy storage to intramuscular stores. Advisors/Committee Members: Hanigan, Mark Daniel (committeechair), Akers, Robert Michael (committee member), McCann, Mark A. (committee member), McGilliard, Michael L. (committee member), Knowlton, Katharine F. (committee member).

Subjects/Keywords: acetate; adipose tissue; clearance; fractional synthesis rate; glucose

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wettathperuma Arachchige, D. N. (2012). Effect of early grain feeding of steers on postabsorptive capacity to utilize acetate and glucose. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/49566

Chicago Manual of Style (16^th Edition):

Wettathperuma Arachchige, Deepthi Nayananjalie. “Effect of early grain feeding of steers on postabsorptive capacity to utilize acetate and glucose.” 2012. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/49566.

MLA Handbook (7^th Edition):

Wettathperuma Arachchige, Deepthi Nayananjalie. “Effect of early grain feeding of steers on postabsorptive capacity to utilize acetate and glucose.” 2012. Web. 18 Jan 2021.

Vancouver:

Wettathperuma Arachchige DN. Effect of early grain feeding of steers on postabsorptive capacity to utilize acetate and glucose. [Internet] [Doctoral dissertation]. Virginia Tech; 2012. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/49566.

Council of Science Editors:

Wettathperuma Arachchige DN. Effect of early grain feeding of steers on postabsorptive capacity to utilize acetate and glucose. [Doctoral Dissertation]. Virginia Tech; 2012. Available from: http://hdl.handle.net/10919/49566

Virginia Tech

12. Smith, Jason Kaleb. Effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers.

Degree: PhD, Animal and Poultry Sciences, 2015, Virginia Tech

URL: http://hdl.handle.net/10919/56596

► Beef cattle producers continuously search for nutritional management options that provide flexibility to production scenarios. Due to its positive effects on maternal productivity, early weaning… (more)

▼ Beef cattle producers continuously search for nutritional management options that provide flexibility to production scenarios. Due to its positive effects on maternal productivity, early weaning is one such alternative strategy that has received considerable interest. To better understand the effects of early weaning on calf productivity, an extensive literature review and three experiments were conducted to evaluate the effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers. In experiment I, which included 90 Angus-sired steers from four calving seasons, early weaning followed by a short ad libitum concentrate-feeding and pasture-backgrounding phase reduced finishing residual feed intake (RFI) by 7 % (P < 0.0001) and increased carcass marbling score (MS) by 10 % (P < 0.01) when compared to conventionally weaned (CW) contemporaries. Similar effects were observed in experiment II, which included 28 Angus and Simmental-sired steers, as early weaning reduced RFI (P < 0.01) and increased carcass MS (P < 0.01). Lung mass of early weaned (EW) steers was greater than their CW contemporaries (P < 0.05), and was inversely related to RFI (R2 = 0.17; P < 0.05). Finishing treatments in this experiment included a high corn ration and an alternative low corn ration that iso-calorically replaced 50 % of the DM from corn with dried corn gluten feed. Iso-caloric replacement of corn reduced lung mass (P < 0.01), and when combined with the observed increase of EW steers suggests that lung development is affected by dietary energy type at various stages of growth. In experiment III, objective analyses of ribeye steaks obtained from steers included in experiment two revealed that early weaning increased cross-sectional muscle fiber area by 28 % (P < 0.001) and tended to increase (P = 0.08) Warner-Bratzler shear force by 36 %. Nonetheless, these effects were not great enough to alter un-trained consumer perception of texture (P ≥ 0.65), juiciness (P ≥ 0.55), flavor (P ≥ 0.25) or overall acceptability (P ≥ 0.34). Collectively, these results indicate that early weaning enhances finishing feed efficiency and carcass marbling without affecting un-trained consumer sensory perception. Advisors/Committee Members: McCann, Mark A. (committeechair), Hanigan, Mark Daniel (committee member), El-Kadi, Samer Wassim (committee member), Johnson, Sally E. (committee member), Greiner, Scott P. (committee member).

Subjects/Keywords: early weaning; feed efficiency; marbling development

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Smith, J. K. (2015). Effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/56596

Chicago Manual of Style (16^th Edition):

Smith, Jason Kaleb. “Effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers.” 2015. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/56596.

MLA Handbook (7^th Edition):

Smith, Jason Kaleb. “Effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers.” 2015. Web. 18 Jan 2021.

Vancouver:

Smith JK. Effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers. [Internet] [Doctoral dissertation]. Virginia Tech; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/56596.

Council of Science Editors:

Smith JK. Effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers. [Doctoral Dissertation]. Virginia Tech; 2015. Available from: http://hdl.handle.net/10919/56596

Virginia Tech

13. Purcell, Scott Hudson. Effect Of A Cidr Insert And Flunixin Meglumine Administered At The Time Of Embryo Transfer On Pregnancy Rate And Resynchronization Of Estrus In Beef Cattle.

Degree: MS, Animal and Poultry Sciences, 2004, Virginia Tech

URL: http://hdl.handle.net/10919/9992

► The objectives of this study were to evaluate the effects of flunixin meglumine (FM), an inhibitor of PGF2a synthesis, administered at the time of embryo… (more)

▼ The objectives of this study were to evaluate the effects of flunixin meglumine (FM), an inhibitor of PGF2a synthesis, administered at the time of embryo transfer (ET) and insertion of an intravaginal progesterone-releasing device (CIDR) at the time of ET on pregnancy rates (PR) and the resynchronization of estrus. Beef cows (n = 796) and heifers (n = 108) at three locations were assigned randomly within age to one of four groups in a 2 x 2 factorial arrangement of treatments with injection of FM (500 mg i.m.; Phoenix Scientific, St. Joseph, MO) 2 to 12 min prior to ET and insertion of a CIDR (1.38 g progesterone; Pfizer, New York, NY) for 13 d immediately following ET as main effects. Fresh or frozen embryos (Stage = 4 or 5; Grade = 1 or 2) were randomly assigned to be transferred to recipients on d 6 to 9 of the estrous cycle. At Location 2 a subset of fresh embryos were split and transferred as fresh half embryos (n = 192). Recipients at Location 2 only (n = 493) were observed for signs of return to estrus beginning 9 d after ET. Recipients that returned to estrus at Location 2 were either bred by AI 12 h after estrus or received an embryo 7 d after estrus. Pregnancy was diagnosed by ultrasonography. Pregnancy rates were analyzed using the LOGISTIC procedure of SAS. Pregnancy rates of split embryo recipients were analyzed separately using the same statistical procedure. Variation in the timing of the return to estrus was determined by an F-test for heterogeneity of variances. Following the initial ET, pregnancy rates of recipients receiving whole embryos were not affected by CIDR administration (P > 0.05; 65% with CIDR, 70% without CIDR), however, there was a significant FM x location interaction on PR (Location 1, 89 vs. 57%; Location 2, 69 vs. 64%; Location 3, 64 vs. 67% for FM vs. no FM, respectively). There was a significant CIDR x FM interaction on PR of recipients receiving split embryos. Pregnancy rates of split embryo recipients receiving CIDR treatment (54%) or FM treatment alone (41%) were less than controls (64%). However, recipients receiving both CIDR and FM had PR similar to controls (60%). The timing of the return to estrus was more synchronous (P < 0.01) for recipients fitted with a CIDR, but PR of recipients bred following a return to estrus did not differ in cows receiving or not receiving a CIDR (P > 0.13; 68 and 62%, respectively). Effects of FM on PR were location dependent and CIDR insertion at ET improved synchrony of the return to estrus. Advisors/Committee Members: Beal, Wilfred E. (committeechair), Hall, John B. (committee member), McCann, Mark A. (committee member), Smith, S. Raymond (committee member).

Subjects/Keywords: Beef Cattle; Flunixin Meglumine; Embryo Transfer; CIDR

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Purcell, S. H. (2004). Effect Of A Cidr Insert And Flunixin Meglumine Administered At The Time Of Embryo Transfer On Pregnancy Rate And Resynchronization Of Estrus In Beef Cattle. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/9992

Chicago Manual of Style (16^th Edition):

Purcell, Scott Hudson. “Effect Of A Cidr Insert And Flunixin Meglumine Administered At The Time Of Embryo Transfer On Pregnancy Rate And Resynchronization Of Estrus In Beef Cattle.” 2004. Masters Thesis, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/9992.

MLA Handbook (7^th Edition):

Purcell, Scott Hudson. “Effect Of A Cidr Insert And Flunixin Meglumine Administered At The Time Of Embryo Transfer On Pregnancy Rate And Resynchronization Of Estrus In Beef Cattle.” 2004. Web. 18 Jan 2021.

Vancouver:

Purcell SH. Effect Of A Cidr Insert And Flunixin Meglumine Administered At The Time Of Embryo Transfer On Pregnancy Rate And Resynchronization Of Estrus In Beef Cattle. [Internet] [Masters thesis]. Virginia Tech; 2004. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/9992.

Council of Science Editors:

Purcell SH. Effect Of A Cidr Insert And Flunixin Meglumine Administered At The Time Of Embryo Transfer On Pregnancy Rate And Resynchronization Of Estrus In Beef Cattle. [Masters Thesis]. Virginia Tech; 2004. Available from: http://hdl.handle.net/10919/9992

Virginia Tech

14. Lopez-Guerrero, Isaias. Estimating forage mass of tall fescue pastures and dry matter intake and digestibility of fescue forage by beef steers.

Degree: PhD, Animal and Poultry Sciences, 2005, Virginia Tech

URL: http://hdl.handle.net/10919/26046

► A series of three experiments were conducted to evaluate different methods of estimating forage mass of tall fescue pastures, and dry matter intake and digestibility… (more)

Subjects/Keywords: intake; forage mass; beef steers; tall fescue; digestibility

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lopez-Guerrero, I. (2005). Estimating forage mass of tall fescue pastures and dry matter intake and digestibility of fescue forage by beef steers. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/26046

Chicago Manual of Style (16^th Edition):

Lopez-Guerrero, Isaias. “Estimating forage mass of tall fescue pastures and dry matter intake and digestibility of fescue forage by beef steers.” 2005. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/26046.

MLA Handbook (7^th Edition):

Lopez-Guerrero, Isaias. “Estimating forage mass of tall fescue pastures and dry matter intake and digestibility of fescue forage by beef steers.” 2005. Web. 18 Jan 2021.

Vancouver:

Lopez-Guerrero I. Estimating forage mass of tall fescue pastures and dry matter intake and digestibility of fescue forage by beef steers. [Internet] [Doctoral dissertation]. Virginia Tech; 2005. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/26046.

Council of Science Editors:

Lopez-Guerrero I. Estimating forage mass of tall fescue pastures and dry matter intake and digestibility of fescue forage by beef steers. [Doctoral Dissertation]. Virginia Tech; 2005. Available from: http://hdl.handle.net/10919/26046

Virginia Tech

15. Stewart, Robert Lawton Jr. The Effect of Three Fescue Types and Lakota Prairie Grass on Copper Status, Dry Matter Intake, and Alkaloid Appearance of Beef Steers.

Degree: PhD, Animal and Poultry Sciences, 2006, Virginia Tech

URL: http://hdl.handle.net/10919/29612

► Tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] is an important forage crop in the United States and covers over 14 million ha. The presence of Neotyphodium… (more)

▼ Tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] is an important forage crop in the United States and covers over 14 million ha. The presence of Neotyphodium coenophialum, an endophytic fungus in tall fescue, is associated with several disorders in grazing livestock, but also increased persistence of tall fescue. These disorders, commonly called fescue toxicosis, are responsible for large economic losses in the beef cattle industry each year. This research examined the effect of three fescue types [endophyte-infected Kentucky 31 tall fescue (E+), endophyte-free Kentucky 31 tall fescue (E-), non-ergot alkaloid-producing endophyte Q4508-AR542 tall fescue (Q)], and Lakota prairie grass (L; Bromus catharticus Vahl.) on animal response, alkaloid appearance, DMI, and copper status. Ergovaline (EV) is the most abundant ergot alkaloid in tall fescue and has previously been considered the causative toxin in fescue toxicosis. More recently it is simpler ergot alkaloids, such as lysergic acid amide (LSA) have been implicated. The objective of the first project was to evaluate animal performance and alkaloid (EV and LSA) appearance in forage and ruminal fluid of steers grazing E-, Q, E+, and L. Average daily gains were greater (P < 0.05) on E-, Q and L compared to E+, and there was a trend (P = 0.11) for gains on E- to be higher than with Q. The seasonal appearance of LSA in ruminal fluid was similar to the seasonal pattern of alkaloids in E+ forage. Ergovaline was not detectable in ruminal fluid of steers grazing E+. Alkaloids were not detectable in forage or ruminal fluid of steers grazing E-, Q, or L. The appearance of LSA in ruminal fluid of steers grazing E+ suggests that this alkaloid may contribute to fescue toxicosis. Low DMI of animals grazing E+ tall fescue is considered a key factor in decreased animal performance compared to other fescue types. The objective of the second project was to evaluate DMI of steers grazing E-, E+, Q, and L pastures using the alkane technique. Dry matter intake of steers grazing E- was greater (P < 0.001) than Q, E+, and L and DMI of steers grazing Q and E+ were similar (P > 0.10) in 2004. In 2005, DMI did not differ (P = 0.23) among fescue types. These results suggest that decreased DMI effects ADG of steers grazing E+ compared to those grazing E-, and lower DMI of Q suggests that the fescue variety Q4508 may not be the optimal variety for the incorporation on non-ergot alkaloid-producing endophytes. Reactive oxygen metabolites such as superoxide (O₂⁻) are produced by both endogenous and exogenous sources and an accumulation of these compounds can result in oxidative stress. Copper/zinc superoxide dismutase (SOD) is a Cu-based antioxidant metalloprotein that acts as a defense against oxidative stress by the scavenging of O₂⁻. <i>Neotyphodium</i>-infected tall fescue is typically lower in Cu which could potentially increase oxidative stress of animals grazing this forage. Therefore the objective of the third project was to investigate the Cu and SOD status of steers grazing E-,… Advisors/Committee Members: Scaglia, Guillermo (committeechair), Wong, Eric A. (committee member), Abaye, Azenegashe Ozzie (committee member), McCann, Mark A. (committee member), Swecker, William S. Jr. (committee member), Fontenot, Joseph P. (committee member), Fike, John Herschel (committee member).

Subjects/Keywords: Intake; Beef Steers; Tall Fescue; Copper; Alkaloids

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Stewart, R. L. J. (2006). The Effect of Three Fescue Types and Lakota Prairie Grass on Copper Status, Dry Matter Intake, and Alkaloid Appearance of Beef Steers. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/29612

Chicago Manual of Style (16^th Edition):

Stewart, Robert Lawton Jr. “The Effect of Three Fescue Types and Lakota Prairie Grass on Copper Status, Dry Matter Intake, and Alkaloid Appearance of Beef Steers.” 2006. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/29612.

MLA Handbook (7^th Edition):

Stewart, Robert Lawton Jr. “The Effect of Three Fescue Types and Lakota Prairie Grass on Copper Status, Dry Matter Intake, and Alkaloid Appearance of Beef Steers.” 2006. Web. 18 Jan 2021.

Vancouver:

Stewart RLJ. The Effect of Three Fescue Types and Lakota Prairie Grass on Copper Status, Dry Matter Intake, and Alkaloid Appearance of Beef Steers. [Internet] [Doctoral dissertation]. Virginia Tech; 2006. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/29612.

Council of Science Editors:

Stewart RLJ. The Effect of Three Fescue Types and Lakota Prairie Grass on Copper Status, Dry Matter Intake, and Alkaloid Appearance of Beef Steers. [Doctoral Dissertation]. Virginia Tech; 2006. Available from: http://hdl.handle.net/10919/29612

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