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Arterial And Venous Adaptations To Short-Term Handgrip Exercise Training, Mahmoud Awad Alomari Jan 2003

Arterial And Venous Adaptations To Short-Term Handgrip Exercise Training, Mahmoud Awad Alomari

LSU Doctoral Dissertations

Four studies on vascular and exercise physiology are presented in this document. The 1st study examined the relationships between measures of fitness and FVF in 55 young [22.6 ± 3.5 years] adults. Estimated VO2peak correlated with arterial inflow (Ainf) [r=0.54; p=0.012] and resting venous outflow (Vout) [r=0.56; p=0.016]. Lastly, HG strength was associated with Vcap [r=0.57; p=0.007] and Vout [r=0.67; p=0.001]. The 2nd study examined the relationship between FVF and exercise tolerance (ExT) in 20 patients with HF [age: 59 ± 13 years] and 10 age-matched controls [age: 51 ± 16 years. The ExT was measured as the maximum …


Oocyte Production In The Early Postpartum Cow, Oscar Perez Jan 2003

Oocyte Production In The Early Postpartum Cow, Oscar Perez

LSU Doctoral Dissertations

The postpartum period has been the focus of numerous studies; however, there is no information available relating to oocyte production in early postpartum cows. Ovaries of early postpartum cows were stimulated with FSH to produce follicular development and oocytes. The objectives of these studies were: (1) to evaluate the use of FSH for oocyte production in early postpartum beef cows, (2) to evaluate follicular response and oocyte quality of beef cows treated with FSH shortly after calving, (3) to evaluate FSH for oocyte production in early postpartum dairy cows, (4) to evaluate responses of FSH-treated, early postpartum beef cows in …


Potential Functionality And Digestibility Of Oryzanol As Determined Using In Vitro Cell Culture Models, Chih-Chun Jean Huang Jan 2003

Potential Functionality And Digestibility Of Oryzanol As Determined Using In Vitro Cell Culture Models, Chih-Chun Jean Huang

LSU Doctoral Dissertations

A mouse lymphatic endothelial cell (SVEC4-10) model and a human intestinal cell (C2BBe1) model in vitro were developed and capable to be used to study antioxidant activity, hypocholesterolemic capability and digestibility of γ-oryzanol. The critical and vital parameters in developing these cell models were the emulsion preparation of hydrophobic compounds for cell models, the consistent management of cell culture, and the selection of cell viability detection methods compatible with the cell lines and the test substances. The results showed that, in some situations, γ-oryzanol could present a more effective antioxidant activity than α-tocopherol, in terms of reducing tert-butyl hydroperoxide promoted …


Thrips Species Composition In Louisiana Cotton And Associated Management Strategies, Donald Ray Cook Jan 2003

Thrips Species Composition In Louisiana Cotton And Associated Management Strategies, Donald Ray Cook

LSU Doctoral Dissertations

The common species of thrips infesting cotton seedlings include flower thrips, Frankliniella tritici (Fitch); tobacco thrips, Frankliniella fusca (Hinds); western flower thrips, Frankliniella occidentalis (Pergande); onion thrips, Thrips tabaci (Lindeman); and soybean thrips, Neohydatothrips variabilis (Beach). In surveys of cotton seedlings at several locations in Louisiana, tobacco thrips was the most common species. The occurrence of flower thrips and soybean thrips was variable. Western flower thrips accounted for < 15% of adults collected at all locations, except two. The performance of acephate and imidacloprid applied as seed treatments and in-furrow, and aldicarb applied in-furrow was evaluated for thrips management across different production environments. Insecticide treatments reduced thrips densities and delayed development of thrips larval populations. The at-planting insecticides influenced thrips species composition in some instances. In studies to evaluate the effects of winter-spring vegetation type (native vegetation and wheat) on aldicarb efficacy, vegetation type did not influence thrips densities on cotton, with one exception. Aldicarb reduced thrips densities regardless of vegetation type. Vegetation type or insecticide treatments did not influence lint yield. Increasing aldicarb rates generally did not improve thrips control. Aldicarb rates currently recommended in conventional tillage systems should be adequate for systems that incorporate winter-spring vegetation as cover crops. Additional studies were conducted to further investigate the influence of thrips on crop maturity and yield. The addition of an at-planting insecticide improved lint yield in one of six tests. Thrips infestations did not affect crop maturity, and with few exceptions boll distribution and boll retention. The majority of these exceptions were associated with the test where the addition of an at-planting insecticide improved lint yield. Several soil applied at-planting insecticides were evaluated against tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), in a field caged infestation study. Acephate and imidacloprid provided little control of tarnished plant bugs. Thiamethoxam and aldicarb resulted in ≥ 50% tarnished plant bug mortality until 10 and 18 DAE, respectively. These are the first reports of western flower thrips infesting cotton seedlings in Louisiana. The addition of an at-planting insecticide provided control of thrips, but affects on crop maturity and yield were variable.


Arm Crank Power And Hyperammonemia In Respones To L-Aspartic Acid Supplementation, William W. Edwards Jan 2003

Arm Crank Power And Hyperammonemia In Respones To L-Aspartic Acid Supplementation, William W. Edwards

LSU Doctoral Dissertations

PURPOSE: To examine the effect of L-Aspartic Acid (L-Asp) supplementation on short-term arm-crank power (i.e. W·min-1) and exercise-induced hyperammonemia in two gender-specific investigations. METHODS: The male investigation (MALE) used nine highly-trained intercollegiate water polo players (WP) and nine moderately-trained college students (MOD); the female investigation (FEM) used 18 recreationally-trained college students. All exercised to exhaustion on two occasions following counterbalanced double-blind ingestion of 12.5g x 2 of L-Asp or placebo (P). The warm-up phase began at 25 W·min-1 and increased in 25 W·min-1 stages every 30 seconds (constant 100 rpm). Performance began (i.e. the subjects turned …


Characteristics Of Fat Free Yogurt As Influenced By The Incorporation Of Folic Acid, Charles August Boeneke Jan 2003

Characteristics Of Fat Free Yogurt As Influenced By The Incorporation Of Folic Acid, Charles August Boeneke

LSU Doctoral Dissertations

Folic acid fortification is used in the prevention of neural tube defects such as spina bifida and ancencephaly, heart defects, facial clefts, urinary tract abnormalities, and limb deficiencies. Although yogurt is not a good source of folic acid, fortification could aid in prevention of above mentioned defects. Fortification of yogurt with folic acid may or may not change its physico-chemical characteristics. Fat free sugar free yogurt was manufactured using 0, 25%, 50%, 75% and 100% of the recommended daily allowance of 400 micrograms of folic acid. Treatments included addition of folic acid at these levels before and after pasteurization. Lemon …


Proportional Assessment Of X And Y Chromosome-Bearing Spermatozoa In Bull And Boar Ejaculates Using Conventional And Real-Time Pcr Techniques, Julius Braden Paul Jan 2003

Proportional Assessment Of X And Y Chromosome-Bearing Spermatozoa In Bull And Boar Ejaculates Using Conventional And Real-Time Pcr Techniques, Julius Braden Paul

LSU Doctoral Dissertations

Considerable variation in the percentage of Y-chromosome bearing spermatozoa (%Y-CBS) between ejaculates in the same male has been reported. Collection regime has been speculated to influence the degree of variation in %Y-CBS in bull ejaculates (Chandler et al., 1998). Experiments were designed to evaluate the effects of two collection regimes on %Y-CBS. Conventional PCR combined with gel electrophoresis and image analysis was employed to determine %Y-CBS in ejaculates from two bulls collected on 7-day intervals and two bulls on 21-day intervals. Real-time PCR technology was used to quantify %Y-CBS in the same ejaculates. Boar ejaculates were also analyzed with both …


A Potential Nutraceutical From Leuconostoc Mesenteroides B-742 (Atcc 13146); Production And Properties, Chang-Ho Chung Jan 2002

A Potential Nutraceutical From Leuconostoc Mesenteroides B-742 (Atcc 13146); Production And Properties, Chang-Ho Chung

LSU Doctoral Dissertations

There is an emerging market for functional oligosaccharides for use in foods. Currently, technology for the production of oligosaccharides is limited to extraction from plant sources, acid or enzymatic hydrolysis of polysaccharides or synthesis by transglycosylation reactions. Oligosaccharides also can be produced using a Leuconostoc fermentation and restricting the polymer size by the addition of maltose. Maltose limits the dextransucrase reaction, yielding high concentrations of a-glucooligosaccharides. Branched oligomers produced by this process were found to be readily catabolized by bifidobacteria and lactobacillus but were not readily utilized by either Salmonella sp., or E. coli, pointing toward their use in intestinal …


Multidemensional Goals Of Farmers In The Beef Cattle An Dairy Industries, Aydin Basarir Jan 2002

Multidemensional Goals Of Farmers In The Beef Cattle An Dairy Industries, Aydin Basarir

LSU Doctoral Dissertations

Farm firm decision making processes have long been of concern to agricultural economists. The concept of maximizing utility rather than profit is an important concept in multidimensional goal research. The prevalence of low or negative net returns in Louisiana beef and dairy production leads to the hypothesis that goals other than profit maximization compete strongly in producers' decisions. The objective of this study is to determine the hierarchy of goals that motivate beef and dairy producers and evaluate them in a multi-dimensional framework. Seven goals were evaluated in producer decision making: Maintain and Conserve Land, Maximize Profit, Increase Farm Size, …


Hypoxanthine Phosphoribosyl Transferase And Early Embryo Development, Michael Gerard Collins Ii Jan 2002

Hypoxanthine Phosphoribosyl Transferase And Early Embryo Development, Michael Gerard Collins Ii

LSU Doctoral Dissertations

The objectives of the first experiment were to ascertain if there were any differences between two mouse areola and adipose tissue cell lines. These cell lines differed only in the presence or absence of the hypoxanthine phosphoribosyl transferase (HPRT) gene. It was found that the cell lines were similar for all parameters. The objectives of the second experiment were to determine if the HPRT gene had an effect on the development of preimplantation mouse embryo. To test this transgenic mouse lines were created. The embryo sex and genotype ratio, the embryo diameter, and the embryo developmental patterns, using a Collin-Ryan …


Dynamic Econometric Modeling Of The U.S. Wheat Grain Market, Carlos Walter Robledo Jan 2002

Dynamic Econometric Modeling Of The U.S. Wheat Grain Market, Carlos Walter Robledo

LSU Doctoral Dissertations

Structural-time series models have not gained much ground in commodity market modeling despite the overwhelming popularity of time series approaches in forecasting and dynamic analyses. This dissertation contributes by applying developments in seasonal cointegration and structural-time series analysis (e.g., Zellner and Palm (1974); Hsiao (1997); Lee (1992); Franses and Kunst (1999); Ghysels and Osborn, 2001) to the study of agricultural commodity markets. The focus is on three research themes. The first theme investigates the role of cointegration and seasonal cointegration for market data, an issue considered timely because most applications assume deterministic seasonal components. The second issue breaks new ground …


Vagal Modulation Of The Heart And Central Hemodynamics During Dynamic Handgrip Exercise And Forearm Occlusion Following Forearm Exercise Training, Heidi A. Kluess Jan 2002

Vagal Modulation Of The Heart And Central Hemodynamics During Dynamic Handgrip Exercise And Forearm Occlusion Following Forearm Exercise Training, Heidi A. Kluess

LSU Doctoral Dissertations

The purpose was to examine the cardiovascular response to an acute bout of handgrip exercise before and after non-dominant arm exercise training. 19 people participated in 16 sessions of exercise training and 16 participants acted as controls (age: 20±1yrs). Blood flow measurements were taken at rest and following 3-min of forearm occlusion (RHBF) using plethysmography. Pneumotachometer, ECG, and blood pressure data were continuously collected during three testing conditions (spontaneous breathing (SB1: 5min), handgrip exercise (0.5hz) at 60%MVC with 50mmHg of pressure on the arm (H60+50mmHg: 5 min), and forearm occlusion (FAO: 3min)). Data were analyzed for respiratory rate, mean R-R …


Effects Of High-Load Eccentric Exercise Training On Rat Soleus Muscle Myofibrillar Disruption Following One-Week Of Hindlimb Suspension Unloading And Subsequent Reloading, Rhonda Dianne Prisby Jan 2002

Effects Of High-Load Eccentric Exercise Training On Rat Soleus Muscle Myofibrillar Disruption Following One-Week Of Hindlimb Suspension Unloading And Subsequent Reloading, Rhonda Dianne Prisby

LSU Doctoral Dissertations

Purpose: This investigation evaluated the effects of a high-load (50% body weight) eccentric exercise training protocol on reloading myofibrillar damage in soleus (SOL) and extensor digitorum longus (EDL) muscles in rats following 7 days (d) of hindlimb suspension unloading (HSU). Methods: 48 female Sprague-Dawley rats were randomly stratified to four experimental groups; exercise + hindlimb suspension unloading (ExHSU), hindlimb suspension unloading (HSU), exercise (Ex) and control (C). The ExHSU and Ex groups underwent a high-load eccentric exercise protocol for ~2.5 weeks. Following exercise training, the ExHSU and HSU groups underwent 7 d of hindlimb suspension unloading and a subsequent 16-19 …


Tryptophan Requirements And The Effects Of Supplemental Tryptophan On Growth Performance, Plasma Metabolites, And Meat Quality In Nursery, Growing, And Finishing Pigs, Amy Christina Guzik Jan 2002

Tryptophan Requirements And The Effects Of Supplemental Tryptophan On Growth Performance, Plasma Metabolites, And Meat Quality In Nursery, Growing, And Finishing Pigs, Amy Christina Guzik

LSU Doctoral Dissertations

This research was conducted to estimate the true digestible Trp (dTrp) requirements in nursery, growing, and late finishing pigs and the effects of supplemental Trp on physiology, behavior, and meat quality. Five experiments were conducted to estimate the dTrp requirement in nursery pigs. Using broken-line regression analysis, dTrp requirements were 0.21, 0.20, and 0.18% for Phase I (5.2 to 7.3 kg), II (6.3 to 10.2 kg), and III (10.3 to 15.7) nursery pigs. In addition, four experiments were conducted to estimate the dTrp requirements in growing and finishing pigs. Using broken-line regression analysis, the dTrp requirement of pigs weighing 30.9, …


Factors Affecting The Selection Of Business Arrangements By Hog Producers In The United States, Christopher Gazzara Davis Jan 2002

Factors Affecting The Selection Of Business Arrangements By Hog Producers In The United States, Christopher Gazzara Davis

LSU Doctoral Dissertations

The structure of the U.S. hog industry is changing rapidly. U.S. hog farms have become smaller in number, larger in size and more specialized. This study examines the factors that influence the hog producer's choice among business arrangements offered in the U.S. hog industry. A national survey was mailed to 4,986 hog producers to determine these factors. The survey consisted of questions covering topics such as: production characteristics, autonomy, transaction costs, risk, social relationships, and demographics. A response rate of 21% was received from the mailed surveys. Four alternative business arrangements were used: independent production, cooperative farming, flat-fee contract, and …


A Game Theoretic Analysis Of U.S. Rice Exports Under Alternative Japanese And South Korean Policy Scenarios, Dae-Seob Lee Jan 2002

A Game Theoretic Analysis Of U.S. Rice Exports Under Alternative Japanese And South Korean Policy Scenarios, Dae-Seob Lee

LSU Doctoral Dissertations

As a result of the Uruguay Round (UR), the impact on the international rice market is profound. In addition, another round of the WTO trade negotiations has started and the impacts of potential policy changes on rice trade are unknown. The major U.S. benefit of the UR has been the access to the Japanese market. However, the U.S. share of this import market has been unstable and the share of Korean rice market is zero percent. Therefore, this study attempts to analyze the potential implication of U.S. rice exports to Japan and Korea. The Japanese and Korean rice economies as …


Development Of Diagnostic Tools For Detecting Expression Of Resistance-Associated Esterases In The Tobacco Budworm, Heliothis Virescens (F.), Huazhang Huang Jan 2002

Development Of Diagnostic Tools For Detecting Expression Of Resistance-Associated Esterases In The Tobacco Budworm, Heliothis Virescens (F.), Huazhang Huang

LSU Doctoral Dissertations

Esterase-based metabolic resistance was studied using biochemical and biological assays with organophosphate (OP)- and pyrethroid (PYR)- resistant tobacco budworms, Heliothis virescens. In biochemical assays, results suggest that: (1) esterase activities toward all substrates used were enhanced in both resistant strains compared with the susceptible strain, suggesting that esterases were involved in resistance; (2) esterase profiles differed depending on the strain and substrate used, and these differences were visualized by using native polyacrylamide gel electrophoresis; 3) esterase activities toward some pyrethroid substrates were significantly higher (P ≤ 0.01) in the PYR-R strain than those in the OP-R strain. These results suggest …


Beef Producer Perferences For Various Livestock Revenue Protection Products: A Conjoint Approach, Deacue Fields Iii Jan 2002

Beef Producer Perferences For Various Livestock Revenue Protection Products: A Conjoint Approach, Deacue Fields Iii

LSU Doctoral Dissertations

The federal government has recently approved legislation to develop revenue insurance products that are affordable and user-friendly for livestock producers. The features of the products will be the ultimate determinant of product acceptance among producers. The objective of the study was to determine the relative importance of livestock revenue insurance product attributes as well as to identify the characteristics of beef cattle producers who prefer certain levels of a given product attribute. Conjoint analysis was utilized to determine the importance of selected attributes. Conjoint Designer was used to develop eleven hypothetical insurance products from four attributes with three levels each. …


Bollworm (Lepidoptera: Noctuidae) Ecology On Genetically Engineered Bollgard And Bollgard Ii Cottons, Jeffrey Gore Jan 2002

Bollworm (Lepidoptera: Noctuidae) Ecology On Genetically Engineered Bollgard And Bollgard Ii Cottons, Jeffrey Gore

LSU Doctoral Dissertations

The ecology of bollworms, Helicoverpa zea (Boddie), on Bollgard and Bollgard II cottons, Gossypium hirsutum L., was studied in field and laboratory experiments. Neonate bollworm larvae were placed on selected components of cotton squares and flowers from non-Bollgard, Bollgard, and Bollgard II cotton varieties. Larval survival was higher on flower anthers and square anthers than on other floral parts for each cultivar. Bollworm survival was lowest on all Bollgard II floral structures. To evaluate larval behavior on Bollgard cotton, first instar bollworms were placed on terminals of non-flowering and flowering cotton plants. Larvae were recovered lower on Bollgard cotton than …


Delayed Phytotoxicity Syndrome In Louisiana Rice Caused By The Use Of Thiobencarb Herbicide, Chiliang Chen Jan 2002

Delayed Phytotoxicity Syndrome In Louisiana Rice Caused By The Use Of Thiobencarb Herbicide, Chiliang Chen

LSU Doctoral Dissertations

Thiobencarb (TB), widely used for the control of broadleaf weeds, grasses, and sedges in rice fields, is considered safe for rice plants when used at recommended rates. TB's reductive dechlorination product, dechlorinated thiobencarb (DTB), is highly toxic to rice. TB is naturally transformed into DTB in field soils in certain areas in Japan and the United States. The resultant syndrome is called delayed phytotoxicity syndrome (DPS). This research was conducted to characterize DPS in Louisiana, to compare the toxicity of TB and DTB to rice, to determine uptake and retention rates of TB and DTB by rice, to confirm that …


Screening And Characterization Of Pathogenic Fungi For Possible Control Of Coptotermes Formosanus, Jianzhong Sun Jan 2002

Screening And Characterization Of Pathogenic Fungi For Possible Control Of Coptotermes Formosanus, Jianzhong Sun

LSU Doctoral Dissertations

Coptotermes formosanus was used as “bait” to isolate pathogenic fungi from soil. Fifteen pathogenic fungal isolates were obtained, all either Metarhizium anisopliae (six isolates) or Beauveria bassiana (nine isolates). There were no differences in numbers of fungal isolates from the three sampling locations. However, significantly more isolates were found in woodlands (eleven) than in pastures (four). Median lethal doses (LD50s) of these fungal species to C. formosanus were interspersed, indicating that fungal isolates rather than species had the greatest effect on virulence. In vitro growth characteristics were significantly correlated with virulence against termites, suggesting that fungal virulence might be predicted …


Superfetation In Beef Cattle, Joel Andrew Carter Jan 2002

Superfetation In Beef Cattle, Joel Andrew Carter

LSU Doctoral Dissertations

Although superfetation has been reported in cattle and other species, there is considerable skepticism as to its existence due to the lack of clear evidence in these reports. Other explanations such as embryonic diapause or differential growth of twins have been suggested as more accurate descriptions of the cases reported as superfetation. The hypothesis of this study is that if a viable pregnancy can ensure maternal recognition in cattle, an asynchronous embryo can develop in a more chronologically advanced uterine environment. The objective was to produce superfetation by (1) ovulation induction and artificial insemination (AI) of pregnant cows and (2) …


Nutrient Profile, Functional Properties, And Microstructure Of Dried Waste Milk Products For Use As A Potential Animal Feed, Ronald I. Thompson Jan 2002

Nutrient Profile, Functional Properties, And Microstructure Of Dried Waste Milk Products For Use As A Potential Animal Feed, Ronald I. Thompson

LSU Doctoral Dissertations

A study was conducted to determine the feasibility of concentrating the wastewater of a butter/powder factory for use as an animal feed. Two concentrated products were evaluated: recovered milk product (RMP), which is the direct factory waste stream; and formulated recovered milk product (FRMP), which is a product made by combining RMP and separator de-sludge in a 3:1 ratio. Three pilot scale dryer systems were used to concentrate the product: a spray dryer, a roller dryer, and a pulse combustion dryer. Dried samples were analyzed for fat, moisture, protein, ash, nitrates, chloride, pH, calcium, phosphorus, sodium and amino acids. Values …


Adoption Of Best Management Practices In The Louisiana Dairy Industry, Noro C. Rahelizatovo Jan 2002

Adoption Of Best Management Practices In The Louisiana Dairy Industry, Noro C. Rahelizatovo

LSU Doctoral Dissertations

The traditional view of the agricultural community as a good steward of the environment has been challenged by increasing concerns about the complex relationship between agricultural production activities and environmental quality. Agriculture provides a large range of products to satisfy human needs. It has also been singled out as major source of water pollution. Largely improved surface water quality has been assessed in the U.S. since the enactment of the Clean Water Act. However, efforts to reduce water pollution continue, targeting discharges from identifiable sources of water pollution and diffused discharges from nonpoint sources. Agricultural producers are encouraged to voluntarily …


Evaluation Of Bacillus Thuringiensis Transgenic Field Corn For Management Of Louisiana Corn Pests, Boris A. Castro Jan 2002

Evaluation Of Bacillus Thuringiensis Transgenic Field Corn For Management Of Louisiana Corn Pests, Boris A. Castro

LSU Doctoral Dissertations

Efficacy of Bt corn hybrids expressing an insecticidal delta-endotoxin through different transformation events was evaluated in Louisiana. Efficacy levels were determined for southwestern corn borer (SWCB), Diatraea grandiosella Dyar; sugarcane borer (SCB), Diatraea saccharalis (F.); corn earworm (CEW), Helicoverpa zea (Boddie); and fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith). Insect (neonates and third instars) susceptibility was evaluated on Bt and non-Bt corn plants (V6 and R1 stages) in field plots and plant tissue in laboratory studies. Bt corn hybrids with MON810 and CBH351 transformation events sustained significantly (P < 0.05) less injury caused by SWCB, SCB, and FAW during infestations at mid-whorl stage. SWCB, SCB, and CEW infestations during silking stage were significantly reduced in Bt hybrids with the MON810 event. However, CEW infestations …


Effects Of Fire Frequency And The Red Imported Fire Ant On Native Insects In A Louisiana Longleaf Pine Savanna, Deanna M. Colby Jan 2002

Effects Of Fire Frequency And The Red Imported Fire Ant On Native Insects In A Louisiana Longleaf Pine Savanna, Deanna M. Colby

LSU Doctoral Dissertations

Ants and ground beetles were collected in pitfall traps from a longleaf pine savanna in the early stages of restoration. Insect abundance and species richness were compared among four treatment combinations of two fire frequencies and presence and absence of an exotic ant, Solenopsis invicta, the red imported fire ant. Amdro® was used to suppress S. invicta. Fire treatments consisted of a single fire in a two year period or two fires in a two year period, one applied each year. Fires were applied late in the growing season both years. Ten of the 28 ground beetle species …


Production Of Transgenic Goats By Somatic Cell Nuclear Transfer, Brett C. Reggio Jan 2002

Production Of Transgenic Goats By Somatic Cell Nuclear Transfer, Brett C. Reggio

LSU Doctoral Dissertations

A series of experiments were conducted to produce transgenic goats by somatic cell nuclear transfer (NT). In all experiments, donor cells were electrically fused to enucleated metaphase II oocytes, then chemically activated. In a preliminary study to evaluate embryonic development following NT with proliferating or quiescent fibroblast or cumulus cells, significantly more embryos reconstructed with quiescent cumulus cells fused (77%) compared with proliferating cumulus cells (41%), proliferating fibroblasts (36%) or quiescent fibroblasts (37%). Improved development to the eight- to sixteen-cell stage was observed when fibroblast cells were serum starved (serum starved 39% vs. serum fed 15%). However, there was no …


Endocrine And Reproductive Responses To Implants Of Deslorein Acetate In Horses, Carrie Ann Johnson Jan 2002

Endocrine And Reproductive Responses To Implants Of Deslorein Acetate In Horses, Carrie Ann Johnson

LSU Doctoral Dissertations

Four experiments were performed to study the effects of the gonadotropin releasing hormone (GnRH) analog, deslorelin acetate (Ovuplant™), on endocrine and reproductive characteristics in mares. The first experiment tested whether anecdotal field reports of Ovuplant causing extended interovulatory intervals would be detectable under controlled, experimental conditions. The use of Ovuplant to hasten ovulation in 13 mares, compared to 12 controls, increased (P < 0.05) the interovulatory interval by 6.2 d and suppressed (P < 0.05) plasma concentrations of both luteinizing hormone (LH) and follicle stimulating hormone (FSH) for approximately 11 d. Two mares receiving Ovuplant did not return to estrus within 30 d. In the second experiment, 10 control mares and 10 mares induced to ovulate with Ovuplant were administered GnRH (50 μg) on d 1, 4, 7, and 10 after ovulation. Again, treated mares had a longer (4.4 d, P < 0.05) interovulatory interval and suppressed LH and FSH concentrations in daily plasma samples. The gonadotropin response to GnRH was lower (P < 0.05) in the deslorelin mares on d 1, 4, and 7, indicating a lack of pituitary responsiveness. In the third experiment, 9 stallions and 12 steroid-treated geldings were used to determine if males were potential models for studying the deslorelin-induced gonadotropin suppression. In both cases, treatment with Ovuplant caused an initial rise in both gonadotropins followed by suppression for about 14 d. In the last experiment, 21 mares were used to determine if multiple doses of deslorelin would cause complete ovarian shutdown. Mares received either sham injections, three Ovuplant implants on the first day, or one implant per day for 3 d (n = 7 per group). Treatment with multiple deslorelin implants increased (P < 0.05) the interovulatory interval by 14.8 d and suppressed LH and FSH concentrations for approximately 25 d, however no mares exhibited complete ovarian shutdown. In conclusion, deslorelin acetate implants in horses in the form of Ovuplant induce short-term increases in LH and FSH secretion followed by long-term suppression of these concentrations and an insensitivity of the pituitary to GnRH. In a small percentage of mares, long-term ovarian shutdown is a possibility.


The Time-Course Of Vascular Adaptations Following Localized Short Term Exercise Training, Jason David Allen Jan 2001

The Time-Course Of Vascular Adaptations Following Localized Short Term Exercise Training, Jason David Allen

LSU Doctoral Dissertations

This is a series of 3 experiments in the area of vasoreactivity. The first study investigated the stability and reproducibility of brachial artery flow-mediated dilation (BAFMD). Twenty-six healthy volunteers underwent 3 scans on 2 days, performed by 2 ultrasonographers, and analyzed by 2 readers. All subjects were tested between 7 and 11am after refraining from food and exercise. Average baseline diameter was 3.48±0.53mm, which increased to 3.71±0.57mm (6.58±4.15%) at peak dilation. ICCC's for days, testers and readers were 0.9188, 0.9394, and 0.8982 respectively. To detect a difference in vasoreactivity of 60% (two-tailed), e.g. 5% vasodilation versus 8% vasodilation, at 90% …


Influence Of Short-Term Endurance Exercise Training On Heart Rate Variability, Clarence Matthew Lee Jan 2001

Influence Of Short-Term Endurance Exercise Training On Heart Rate Variability, Clarence Matthew Lee

LSU Doctoral Dissertations

The purpose of this investigation was to determine if 8 exercise endurance training (ET) sessions over 2 weeks significantly alters cardiac autonomic modulation, as measured by heart rate variability (HRV). Twenty-four college-aged males were recruited for this study and were randomized into either an exercise group (EX; n=12) or a control group (CT; n=12). EX underwent 2 weeks of ET on a cycle-ergometer (frequency: four times/week; duration: 40 minutes; intensity 80-85% HRreserve), whereas CT was instructed not to alter their previous level of physical activity. Five-minute ECG tracings were collected for HRV under the following conditions: 5 minutes of paced …