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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Replacing sunflower oilcake with Sericea lespedezaand/or urea on feed digestibility and milk production of Saanen goats

Malate, Andries January 2017 (has links)
In conditions where supplementation of poor quality diets is a major challenge, forage legumes such as Sericea lespedeza can be a good alternative supplement for protein at lower cost than most commercial concentrates. From studies done on Sericea lespedeza it is found plausible and valuable to supplement urea with Sericea lespedeza to strategically combat the deleterious effect of condensed tannins in the Sericea lespedeza and provide nitrogen in the rumen. This study was aimed to evaluate the effect of replacing sunflower oilcake with urea (a rumen degradable protein RDP source) or Sericea lespedeza (rumen undegradable protein RUP source) mixed with urea as nitrogen/protein sources on nutrient utilization, milk yield and milk composition of Saanen dairy goats. A digestibility and lactation study were conducted at the University of Pretoria Research Farm and chemical analysis performed at the University Nutrilab. A 30 days digestibility study was conducted on male Saanen goats after the lactation study, with 23 days adaptation and 7 days data collection period. Nine male goats were randomised and allocated to the three treatments in metabolism cages. In the lactation study 36 dairy goats were blocked according to milk collected on first month of lactation into high, medium and low milk yielders, then allocated to the three treatments of total mixed rations containing sunflower oilcake (T1) at 7% main protein source, T2 (urea at 1%) and T3- Sericea lespedeza at 12.5% mixed with urea according to a complete randomised block design (CRBD). Milk samples were collected from individual goats monthly at two consecutive milking’s. The samples were analysed for milk fat, protein, lactose, somatic cell count and milk urea nitrogen using a Milko-Scan analyser (at Irene Lacto lab). In the digestibility study, dry matter intake was significantly higher for goats fed on Sericea lespedeza with urea (T3) diet than goats fed on T1 and T2 diet. Goats on T3 diet had also significantly higher organic matter and crude protein intake than those goats fed on the other two TMR diets. The results also shows that the mean daily milk yields for the goats in the T1, T2 and T3 were 2.56, 2.46 and 2.52 kg per day respectively. T2 group had higher milk fat % (3.61) and higher milk urea nitrogen (MUN - 25.70 mg N/dl) than the other two treatments. T1 had significantly higher milk protein %. There was a great difference in milk composition of the afternoon milk as compared to the morning milk. The three TMRs had no significant difference in the nitrogen utilization and nitrogen excretion. It is then concluded that Sericea lespedeza mixed with urea can be used as subsititutes for sunflower oilcake in the diets of dairy goats since no negetive effect was found. However further investigations are needed. / Dissertation (MSc Agric)--University of Pretoria, 2017. / DAAD-NRF / International Foundation for Science (IFS) / Animal and Wildlife Sciences / MSc (Agric) / Unrestricted
2

Responses of grassland birds and butterflies to control of sericea lespedeza with fire and grazing

Ogden, Sarah B. January 1900 (has links)
Master of Science / Division of Biology / David A. Haukos / Sericea lespedeza (Lespedeza cuneata) is an invasive forb that reduces native grass and forb abundance in tall-grass prairie by up to 92%. Controlling invasions is difficult because traditional land management tools used in the Flint Hills, broad spectrum herbicides, spring prescribed fire, and cattle grazing, are ineffective against sericea. Recent research has demonstrated, however, that mid- and late summer prescribed fire and spring fire with early season grazing by steers followed by late season grazing by sheep are effective at reducing sericea whole plant mass, number of seeds produced, and seed mass. Field results were from two separate experiments conducted in tall-grass prairie study sites in the Flint Hills. On a Geary County, Kansas, study site, the utility of 1) spring fire (control), 2) mid-summer fire, and 3) late summer fire on sericea control were compared. On a Woodson County, Kansas, study site, the utility of 1) spring fire with early season steer grazing followed by rest (control) and 2) spring fire with early season steer grazing and late season sheep grazing on sericea control were compared. At the same study sites, I measured responses by the native wildlife community to use of summer fire and sheep grazing, relative to their controls, to manage sericea lespedeza. Specifically, my objectives were to compare grassland songbird density, grassland songbird nest survival, and grassland butterfly species composition and density among treatments at both study sites. I also related patterns in the vegetation community of each treatment for each study site to respective patterns in grassland bird and butterfly communities. Within study sites, density, nest density, and nest success of grassland bird communities responded similarly to treatments and controls, with the exception that densities of Grasshopper Sparrows (Ammodramus savanarrum) were 3.4- and 2.2-fold greater in mid- and late summer fire plots than spring fire plots, respectively, in the Geary County study site. Species compositions of butterfly communities were similar across treatments within experiments, but grassland specialist species comprised only 8.6 and 1.2% of all butterfly observations in the Geary County and Woodson County experiments, respectively. Grassland specialist butterfly species may benefit from summer fire, as their nectar sources were more abundant in Summer Fire plots than Spring Fire plots. Overall, within each experiment, grassland bird and butterfly communities were similar across treatments, suggesting that treatments did not negatively affect grassland songbird and butterfly communities. I additionally demonstrated that Dickcissel (Spiza americana) nest sites contain a lower proportion of sericea than random points, the first evidence that the invasion is detrimental to grassland songbird species. Lacking control, the continued sericea invasion will out compete cumulatively more forb plants resulting in declining quality of grassland bird nesting habitat on the landscape. Controlling sericea lespedeza invasions will allow native forb species to increase in abundance and improve the condition of grasslands for native wildlife and livestock producers. Therefore, I advocate use of summer fire or spring fire with a combination of cattle and sheep grazing to control sericea lespedeza with the long-term goal of tall-grass prairie restoration.
3

Assessing the potential of mixed grazing goats with beef cattle to improve animal performance and increase the utilization of marginal pasturelands in the Appalachian coal region

Webb, Darryl Matthew 26 May 2008 (has links)
Reclaimed coal-mined lands in the Appalachian region can be successful established and utilized for beef cattle production. Currently, these areas are underutilized partly due to an increase in invasive plant species, such as multiflora rose (Rosa multiflora Thunb. Ex Murr.), autumn olive (Elaeagnus umbellata Thunb.), and sericea lespedeza (Lespedeza cuneata (Dum.-Cours.) G. Don). The steep topography and low economic returns from beef cattle make conventional control methods inhibitive. Goats are effective browsing on invasive plant species. An experiment was conducted in 2006 and 2007 at the Powell River Research and Education Center near Wise, VA (77° 43' 30" west longitude, 38° 57' 30" north latitude, elevation 155.5 m) to determine the effects of an ungrazed control, cattle alone grazing, and mixed grazing goats with cattle on forage biomass, botanical composition, relative plant abundance, and animal performance. The three treatments included an ungrazed control, cattle grazing alone, and mixed grazing goats with cattle. Experimental design was a randomized complete block design with two replicates for the control and three replicates for the grazed treatments. Three times during the grazing season the following were measured, analyzed or assessed: nutritive values of pasture, autumn olive, multiflora rose, and sericea lespedeza were assessed; forage biomass was determined by clipping four 0.25 m² quadrants per control replicate and eight 0.25 m² quadrants per grazed replicate; botanical composition and relative abundance of plant species was assessed by the Double DAFOR method from five fixed points in each control replicate and ten fixed points in each grazed replicate; animals were weighed; autumn olive shrub height was measured with a clinometer from a distance of 10 m from the shrub. Branch length was measured with a tape measure from the base of the branch to the end tip. Shrub survival was measured by counting shrubs in each replicate and determining visually percent leaf-out. Each year, control and cattle alone treatments had greater (P < 0.05). Generally, grass content increased in the grazed treatments from spring to fall while weed content increased in the control treatment (P < 0.05). By the end of the two experimental years, the legume components of the pasture were low. This was more evident in the ungrazed control than the grazed treatments. The relative abundance of tall fescue and orchardgrass (P < 0.05) increased in grazed treatments while sericea lespedeza became a dominant weed in the control (P < 0.05). Goats showed high preference for sericea lespedeza and maintain this plant in a leafy, vegetative stage. This leafy, vegetative growth was found to acceptable to cattle. Cattle performance was not affected by treatment (P < 0.05) but total animal output was higher for mixed grazed compared to cattle alone treatments (P < 0.05). The nutritive values of multiflora rose, autumn olive, and sericea lespedeza were higher than pasture in most instances (P < 0.05). In our experiment, autumn olive was severely impacted by goat browsing. Shrub survival was lower in mixed grazing (61%) by the end of the experiment compared to over 90% for the control and cattle grazing treatments (P < 0.05). Overall, pastures were utilized more uniformly in mixed grazing compared to other treatments. Mixed grazing goats with cattle appear to be a viable option for livestock producers in the Appalachian coal mining region. / Master of Science
4

Effects of prescribed fire timing on vigor of sericea lespedeza in the Kansas Flint Hills

Alexander, Jonathan Andrew January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / K C Olson / We evaluated effects of annual, prescribed burning on vigor of the noxious weed, sericea lespedeza (Lespedeza cuneata; SL) in native tallgrass prairie over a 4-yr period. We hypothesized that annual prescribed burning conducted during the growing season would selectively pressure SL, whereas locally-conventional, dormant-season prescribed burning would have no effect on SL. A 50-ha native tallgrass pasture infested with SL (initial basal frequency = 2 ± 1.3%, initial aerial frequency = 36 ± 3.4%) was used for our study. It was divided along watershed boundaries into 9 fire-management units (5 ± 2.6 ha) for this experiment. Burn units were assigned randomly to 1 of 3 prescribed-burning times (n = 3 / treatment): early spring (1 April; EARLY), mid-summer (1 August; MID), or late summer (1 September; LATE). Forage biomass, SL aerial frequency, SL stem length, SL seed production, soil cover, and plant species composition were measured along single, permanent 100-m transects in each burn unit. Treatment and measurement date influenced forage biomass and SL stem length (treatment × time). Forage biomass was not different (P ≥ 0.43) between treatments on 17 July; however, forage biomass was greater (P < 0.01) in EARLY than MID and greater in MID than LATE on 10 October. Maximum stem length of SL was less (P ≤ 0.02) in MID and LATE than in EARLY on 17 July and on 10 October. Aerial frequency of SL was least (main effect – P < 0.01) in LATE, intermediate in MID, and greatest in EARLY, whereas basal frequency of SL was less (P < 0.01) in MID and LATE compared with EARLY. Whole-plant dry weight and seed production of SL at dormancy were greatly diminished (P ≤ 0.02) in MID and LATE compared with EARLY. Occurrence of bare soil, litter cover, and total basal plant cover were not different (P ≥ 0.21) between treatments. Similarly, basal cover of grasses, forbs, and shrubs were not different (P ≥ 0.24) between treatments. We interpreted these data to indicate that annual prescribed burning during the growing season had strong suppressive effects on SL compared to locally-conventional, early-season prescribed burning and produced no apparent detrimental effects on soil cover or non-target plant species. Post-fire regrowth was sufficient to prevent erosion and soil-moisture loss during the subsequent dormant season and would have allowed light to moderate grazing during the ensuing winter. Key words: Lespedeza cuneata, prescribed fire, range improvement
5

Impacts of patch-burn grazing on livestock and vegetation in the tallgrass prairie

Rensink, Cade Brion January 1900 (has links)
Master of Science / Department of Agronomy / Walter H. Fick / Patch-burn grazing is a relatively new concept in terms of rangeland management. While numerous benefits have been associated with this system, in the tallgrass prairie of Kansas, cattle production and sustainability of rangeland are critical. In 2006, 253 ha at the KSU Bressner Range Research Unit in Woodson County, Kansas were subjected to spring patch-burn grazing (using one-third portions) and traditional full-burn grazing. Each treatment within the split-block design was replicated four times for 3 years. The objectives were to evaluate whether livestock performance would be compromised under this grazing system, to monitor the health of the rangeland, and to observe the usefulness of this tool as a potential control of the invasive plant sericea lespedeza [Lespedeza cuneata (Dumont) G. Don]. In regards to cattle performance, burn treatments had no significant difference in average daily gain (p≥0.10) in any of the 3 years. On average, cattle utilized 61% of the current year’s forage production in patch-burned portions, which was higher (p≤0.10) than that of unburned (30%) and full-burn (41%) portions. Results of the botanical composition show forb and woody plant composition did not differ between treatments, however differences (p≤0.10) were present in grass composition. Total annual grasses increased 19.1 percentage units under patch-burn and 2.1 units under full-burn, while total perennial grasses decreased 18.4 and 1.1 units, respectively. When evaluated by treatment area (one-third portion), results indicated that the 3-year cycle did allow enough time for recovery. At 2 years after treatment (2-YAT), no significant difference in composition(p≥0.10) was present between initial patch-burn portions and the full-burn pastures. Finally, in only 1 year of the study did cattle statistically consume a greater percentage of sericea lespedeza plants (p≤0.10) in the patch-burned portions (92%) than in full-burned pastures (35%). Biomass utilization did not differ (p≥0.10) between burn treatments. Surprisingly, there was a trend for the number of plants in the sampled areas of the patch-burn portions to decrease throughout the cycle. However, at the conclusion of the 3-year cycle, sericea densities did not differ(p≥0.10) between treatments. Patch-burn grazing shows promise as a potential management tool for Kansas land managers.
6

Effects of prescribed burning on undesirable plant species and soil physical properties on tallgrass prairies

Ungerer, James L. January 1900 (has links)
Master of Science / Department of Agronomy / Walt Fick / Prescribed burning has been a common conservation practice on native prairie dating back to the days of pioneer settlement. Advantages include increased forage quality, reduction of undesirable plants, improved wildlife habitat, removal of accumulated dead plant litter and relatively low costs. While spring is the commonly accepted time to burn, little research has been conducted on late-summer and fall burning for specific objectives that include targeting undesirable plant species and measuring potential effects on soil physical properties. The first part of this study was to evaluate the effect that prescribed burning has on population dynamics of sericea lespedeza (Lespedeza cuneata [Dumont] G. Don), rough-leaf dogwood (Cornus drummondii Meyer), and additional woody species. Stem counts and cover estimates were taken from 20, 0.25-m[superscript]2 frames prior to and post-burn. Change in botanical composition, plant density, frequency, and Daubenmire canopy cover estimates were calculated. Sericea lespedeza plant frequency across all clay upland burns decreased 2.27% and increased 4.76% across all loamy/limy upland burns the first growing season post-burn. Dogwood densities increased 3.12 stems m[superscript]-[superscript]2 on spring burns compared to a decrease of 0.30 stems m[superscript]-[superscript]2 on unburned plots the first growing season post-burn. Changes in frequency of other woody species the first growing season post-burn showed significant interactions between burn treatment and ecological site, and between ecological site and year. A significant interaction between burn treatment and ecological site was found on total woody species plant composition changes two growing seasons post-burn for the first year of burn treatments. The secondary part of this study was to evaluate the effect of prescribed burning on soil bulk density and wet-aggregate stability. Soil samples were collected along the same line-transects used for vegetation sampling. Significant differences among mean weight diameters (MWD), percent water-stable aggregates (WSA), and WSA size fractions occurred between burned and unburned soils following burning in the fall of 2011. Monitoring plant and soil response to prescribed burning in different seasons may lead to adjustments being made in management of rangelands where sericea lespedeza, dogwood, and additional woody species occur.
7

Sericea lespedeza (Lespedeza cuneata): seed dispersal, monitoring, and effect on species richness

Blocksome, Carolyn E. January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Walter H. Fick / Sericea lespedeza [Lespedeza cuneata (Dumont) G. Don] is a rangeland weed of the tallgrass prairie of Kansas. Experiments were carried out during the 2001-2003 growing seasons (June-November) to examine the relationship between sericea lespedeza and other rangeland species, wildlife use and dispersal of sericea lespedeza propagules, and the relationship between sericea lespedeza stubble height and utilization by livestock. Sericea lespedeza cover was positively correlated with violet lespedeza (r=0.25) [Lespedeza violacea (L.) Pers.], heath aster (Aster ericoides L.) (r=0.23) and total forb cover (r=0.56). Sericea lespedeza composition was negatively correlated with big bluestem (Andropogon gerardii Vitman.) (r=-0.27) and sideoats grama [Bouteloua curtipendula (Michx. Torr.)] (r=-0.27) composition and positively correlated with western ragweed (Ambrosia psilostachya D.C.) (r=0.21) and violet lespedeza (r=0.36) composition. Sericea lespedeza density was inversely related to forb species richness on all sites. On half the sites, there was also an inverse relationship between grass species richness and sericea lespedeza density. Grazed sites had less difference in grass species richness between high and low levels of sericea lespedeza densities. There was no evidence of an ecological threshold to the detriment of species richness with increasing sericea lespedeza density. Cattle digestive processes did not affect sericea lespedeza germination. Quail digestive processes enhanced germination of the few seeds that were excreted. Quail diet selection was investigated with a field study. Five out of 49 crops collected contained seed classified as sericea lespedeza. None of these seeds germinated in the greenhouse. Both cattle and quail could potentially disperse sericea lespedeza seed, but voluntary consumption appears to be low for both species, at least during November when other food is available. An height-weight table estimating percent utilization for various grazed and ungrazed heights of sericea lespedeza was constructed. Coefficient of determination values were greater than 0.85 between plant height and weight, indicating that the heightweight method was appropriate for estimating sericea lespedeza utilization. Using additional regression analysis, a chart for estimating forage from percent of plants grazed was constructed.

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