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Effect of Fertilization on Woody Plant Chemistry: The Role in Diet Selection by GoatsGobena, Amanuel 01 May 1988 (has links)
Lack of forage quantity and quality limit livestock production during the dry season in northeast Brazil. Coppice produced following cutting of tree species in this area has the potential to increase forage quantity and quality during the dry season, because trees that coppice retain green foliage throughout most of the dry season. However, the palatability of coppice is often low.
From a theoretical standpoint, woody plants with inherently slow growth rate should be less palatable to herbivores than plants with inherently fast growth rates, because plants that grow slowly allocate more carbon to compounds such as tannins and resins that reduce palatability. I tested this hypothesis with four tree species (Mimosa caesalpiniaefolia, Croton sonderianus, Auxemma oncocalyx, and Caesalpinia bracteosa) growing on both fertile (non-calcic brown) and infertile (lithic) soils. Inherent plant growth rates were determined by growing young plants of all species on both soil types in a greenhouse. Plants were fertilized with NPK (150 or 300 kg/ha) and watered to field capacity. Urea ((NH2)2CO),diammonium phosphate ( NH4)2 Po4 and KCL were used as sources of fertilizer. On fertile soils, Mimosa had the highest inherent growth rate, followed by Auxemma, Croton, and Caesalpinia. In pen and field trials, Mimosa was preferred by goats, followed by Auxemma, Croton, and Caesalpinia. Results were similar on infertile soils, but Croton had a higher growth rate than Auxemma, and Croton was preferred to Auxemma by goats . Fertilization with 150 or 300 kg/ha of NPK increased palatability of coppice of all plant species to goats on both fertile (non-calcic brown) and infertile (lithic) soils.
Fertilization affected the chemical and physical characteristics of the four plant species. Concentrations of tannins and lignins decreased as did leaf toughness, while nitrogen, phosphorus, and calcium increased. In vitro organic matter and neutral detergent fiber digestibilities did not change. The prediction that fertilized plants would be lower in carbon based compounds than the unfertilized plants was supported by the results of my study.
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The Effectiveness of Two Types of Adjunct Acupuncture Exposures on In Vitro Fertilization OutcomesVacovsky, Lindsey 01 January 2019 (has links)
One out of every 8 couples experiences infertility. Few publications exist examining the association between the addition of adjunctive therapies when applied to the in vitro fertilization (IVF) procedure and pregnancy outcome. The purpose of this study was to compare the effectiveness of 2 types of adjunct acupuncture exposures on IVF outcomes by applying the concept of the epidemiology triad. The association between the type of adjunct acupuncture exposure received (the independent variable) and pregnancy (the outcome) was determined via binary logistic regression using SPSS software. Medical records of women having received the IVF procedure along with adjunct acupuncture were eligible for analysis. A total of 444 qualifying patient records were collected from participating acupuncture clinics. Analysis of the data showed there was no significant difference in pregnancy outcomes between the two types of adjunct acupuncture reviewed. However, an increase in pregnancy outcomes was noted in the adjunct acupuncture groups when compared with pregnancy outcomes in IVF protocols without the addition of adjunct acupuncture. Additionally, there was no significant difference between pregnancy outcomes when accounting for various race or age groups. This study has implications for positive social change in the form of both providing data to women undergoing the IVF procedure to allow for more informed decision making and ultimately with hopes of improving the odds of success to the nearly 165,000 IVF procedures undergone in America each year.
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Comparação de dois diluidores para o armazenamento de sêmen bovino utilizado na fecundação in vitro /Prado, Rodolfo Bilachi. January 2009 (has links)
Orientador: Marion Burkhardt de Koivisto / Banca: Paulo Henrique Franceschini / Banca: Sony Dimas Bicudo / Resumo: O processo de criopreservação afeta a capacidade funcional dos espermatozóides, diminuindo a fertilidade. Tendo conhecimento desses danos a diluição do sêmen é necessária antes de submetê-lo ao choque térmico. O objetivo deste trabalho foi avaliar o sêmen bovino congelado com dois diferentes diluidores. O ejaculado de quatro touros foi dividido em duas partes iguais, uma delas submetida ao diluidor Tris e gema de ovo (A) e a outra ao diluidor à base de lecitina de soja (Andromed®) (B). Após a diluição o sêmen foi congelado e armazenado em nitrogênio líquido de acordo com os padrões pré-estabelecidos da central de inseminação artificial. No experimento I, cinco palhetas do diluidor A e B de cada touro foram descongeladas e avaliadas quanto à motilidade (análise subjetiva e computadorizada), vigor, concentração, morfologia espermática e teste de termo-resistência lento (TTL), avaliação da integridade de membranas por meio da associação das sondas Iodeto de Propídio (PI), Isotiocionato de Fluoresceína - Pisum sativum (FITC-PSA) e Carbocianina Catiônica Lipofílica (JC-1) e avaliação funcional da membrana plasmática através do teste hiposmótico (HIPO). A avaliação da integridade da cromatina foi realizada pelo método de coloração com laranja de acridina (LA). No experimento II, o sêmen congelado com os diferentes diluidores foi utilizado na fecundação in vitro (FIV), sendo observada as taxas de clivagem e desenvolvimento embrionário in vitro. A análise estatística foi efetuada através dos testes de Análise de Variância (ANOVA), teste de Tukey e teste de Wilcoxon. Em relação aos resultados obtidos com os experimentos I e II não foi observado diferença estatística entre os diluidores testados, concluindo-se que o diluidor composto por lecitina... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Nowadays the embryo transfer is a biotechnology widely used, however not much is know about the best place to put embryos into the uterine horn ipsilateral to the corpus luteum (CL). In addition, not much is known about the morphological characteristics thorough the uterine horn and if it could improve or damage the uterine environment. The aims of this study were: to investigate the effect of the site of embryo placement (cranial, medial or caudal) into the uterine horn adjacent to the CL on pregnancy rates; to analyze the morphology from these tree portions of the both uterine horns adjacent and opposite to CL using histology and scanning electron microscopy; and establish the relation between pregnancy rates and morphofunctions characteristics to indicate the best place to transfer embryos. In this study 600 in vivo produced embryos (fresh and frozen-thawed) and 315 in vitro produced embryos were transferred to Holstein and crossbred recipients, in order. Nine crossbred heifers were slaughtered approximately seven days after estrus and the uterus were studied to analyze its morphology at the same time that the embryos have been transferred. The results showed that the site of embryo placement did not influence (P>0.05) the pregnancy rates in recipients receiving fresh embryos during summertime. During the winter, the pregnancy rates were greater (P<0.05) for fresh embryos transferred into the caudal portion of the uterus horn than cranial portion. For animals that received in vitro produced embryo, the site of embryo placement did not interfere (P>0.05) in the pregnancy rates. Morphophological characteristics observed by histology and scanning electron microscopy was similar in all parts of the uterine horn ipsilateral to the CL studied. However, the average number of blood vessels counted was lower in the contralateral uterine... (Complete abstract click electronic access below) / Mestre
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Mechanisms and Signal Transduction Pathways Involved in Bovine Oocyte ActivationBayles, Ammon Hanson 01 December 2012 (has links)
In addition to contributing genes at fertilization, the sperm cell induces the oocyte to leave its arrested state and resume metabolism in the process of activation. A hallmark of oocyte activation is a release of intracellular calcium (Ca2+i) from the endoplasmic reticulum. The mediators of oocyte activation have been studied in many animal models, while little is known in the bovine model. Both Src Family Kinase (SFK) and Phospholipase C (PLC) enzymes have been reported to be involved in oocyte activation in other animal models. In this dissertation are described experiments that define the role of SFK and PLC enzymes in the pathway leading to Ca2+i and calcium induced calcium release in bovine oocyte activation. Western blotting was used to discover that SFKs Src, Hck, and Lck are present in matured bovine oocytes, and Src, Blk, and Yes are present in acrosome reacted bovine spermatozoa. The PLC δ1 and δ3 are present in both matured bovine oocytes and spermatozoa. PLC δ4, γ2, and η2 are present in matured bovine oocytes. Microinjecting a known general SFK inhibitor, PP2, significantly decreases both Ca2+i and cleavage rates. Microinjecting a 13 amino acid peptide that mimics the phosphorylated carboxyl terminal region of pp60c-src decreases both Ca2+i and cleavage rates. Microinjecting a downstream substrate of pp60c-src sequestered any signal produced by Src and decreased Ca2+i and cleavage rates. Microinjecting primary antibodies raised against PLC isotypes blocked both Ca2+i and cleavage rates, giving insight to the mechanism of calcium induced calcium release in the bovine model. The PLC isotypes δ3, δ4, and γ2 decreased Ca2+i oscillations and cleavage rates, indicating they are involved in both IP3R and RyR activation. PLC δ4 and η2 did not impact Ca2+i but did significantly decrease cleavage rates. The data presented in this dissertation increase the understanding of the pathway leading to bovine oocyte activation and further confirm that the detailed pathway differs among animal models.
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Disturbed Alpine Ecosystems: Seedling Establishment of Early and Late Seral Dominant SpeciesChambers, Jeanne C. 01 May 1987 (has links)
This study examined the effects of seedbed and seedling environment on establishment of early and late seral dominant alpine species. Species studied included late seral dominant forbs (Geum rossii, Artemisia scopulorum, and Polemonium viscosum), early seral dominant forbs (Potentilla diversifolia and Sibbaldia procumbens), a late seral dominant grass (Festuca idahoensis), and early seral dominant grasses (Calamagrostis purpurascens and Deschampsia cespitosa). Germination responses of each species to wet vs. dry cold stratification and light vs. dark conditions were investigated. No statistical differences were observed in the seed germination of early and late seral dominant forbs or early and late seral dominant grasses, but significant differences were observed in the responses of grasses and forbs. Seed germination of forbs was greater under light than dark conditions and following wet cold storage.
Effects of fertilization on growth responses and nutrient uptake of G. rossii and D. cespitosawere evaluated in a factorial greenhouse experiment in which seedlings of each species were grown at four levels of nitrogen (N) and phosphorous (P). The late seral dominant forb responded more like a species from a low-nutrient environment exhibiting lower relative growth rates, higher root:shoot ratios, and a smaller response to N than the early seral dominant.
A field experiment on the Beartooth Plateau, Montana, examined the soil environment and seedling emergence, growth, and survival of seeded early and late seral dominants on loamy sand soils of a severe disturbance and on peat soils of an undisturbed area during two growing seasons. Effects of fertilizer and mulch were examined on the severely disturbed area. Differences between uncleared turf and turf cleared of vegetation (gap disturbance) were evaluated on the undisturbed area. The gap disturbance had higher levels of N and P and warmer soil than the severe disturbance or vegetated undisturbed area. Soil water potentials were never low enough to result in plant stress. Seedling growth was slow - .005 g to .04 g dry weight the first growing season and .02 g to .20 g the second growing season. Growth was greatest on the gap disturbance and on fertilized plots of the severely disturbed area. Early seral dominants had the largest seedlings and the smallest R/R+S ratios. Mortality was low - odds of .50 were rarely exceeded even after two years. Survival was higher on warm, nutrient rich soils of the gap disturbance. Mulch increased emergence and survival on the severe disturbance. Fertilization increased mortality, probably because an initial pulse of N was followed by a rapid decline. Higher mortality occurred in 1986 than 1985 as 1986 had a shorter growing season and cooler air and soil temperatures early in the growing season.
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The Stress Response, Psychoeducational Interventions and Assisted Reproduction Technology Treatment Outcomes: A Meta-Analytic ReviewMumford, Karen Rose 09 November 2004 (has links)
The psychological impacts of infertility have been well documented in the literature, providing evidence to support that at least some women who confront infertility are at risk for heightened distress and depressive symptoms. In response to this accumulated evidence, it has been argued that psychoeducational interventions may provide an important component to the treatment of infertility. While several theoretical models postulate the effects of stress on infertility treatment outcomes, results of these investigations have led to conflicting conclusions. However, a synthesis of the accumulated data examining the effects of stress on ART treatment outcomes was nonexistent until the conduct of this study. Therefore, the purpose of this study was to investigate the impact of stress on ART treatment outcomes and to determine whether psychoeducational interventions mitigate the impact of stress experienced by women during an ART treatment program. Two hypotheses were tested: 1. Increased levels of stress will be associated with a lower likelihood of Assisted Reproductive Technology (ART) treatment success, and 2. Psychoeducational interventions will mitigate the effects of stress experienced during Assisted Reproductive Technology (ART) treatment. A meta-analysis analyzing the results for each hypothesis was tested through a hierarchical linear regression model. A total of 13 studies, representing 43 effect sizes, were included in the analysis investigating the relationship between stress and ART treatment outcomes. Results of the HLM regression model suggest that stress has a small negative association with ART treatment outcomes (d=0.2012, p< .05). The analysis investigating the relationship between psychoeducational interventions and stress included a total of 4 studies, representing 12 effect sizes. Empirical evidence gathered through this analysis revealed that the effect of psychoeducational interventions on the stress experienced by women participating in an ART treatment program were not statistically significant (d=0.3071, p>.05). However, because this analysis was based on such a small sample of studies, generalizations regarding the efficacy of psychoeducational interventions cannot be made. Therefore, research aimed at investigating the impacts of a variety of programs should continue in an effort to provide more conclusive information.
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The in vitro produced cow embryo : factors affecting development and metabolismSteeves, Tracey Elizabeth, 1968- January 2000 (has links)
Abstract not available
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Factors affecting the developmental competence of pig oocytes matured in vitro.Bagg, Melanie Anna January 2007 (has links)
Pre-pubertal pig oocytes possess lower developmental competence than those from adult pigs following in vitro maturation (IVM). Previous studies have demonstrated that exposure of pre-pubertal oocytes to 1 mM dibutyryl cAMP (dbcAMP), a membrane permeable cyclic adenosine monophosphate (cAMP) analogue, for the first 20 h of IVM improves the rate of blastocyst development. Developmental competence of in vitro matured pig oocytes has been reported to increase with increasing follicle size. In this thesis, experiments were carried out using pre-pubertal and adult pig oocytes to investigate the relationship between donor age, intra-oocyte cAMP level and follicle size in terms of oocyte maturation and developmental competence. These experiments demonstrated that, while ovarian, follicular and oocyte morphology are immediately altered with the onset of puberty, pre-pubertal oocytes must be exposed to more than the first oestrous cycle to achieve improved developmental competence in vitro. Later experiments demonstrated that pre-pubertal oocytes accumulate less cAMP during IVM, undergo more rapid meiotic progression and display reduced rates of blastocyst development compared to in vitro matured adult oocytes. Treatment with dbcAMP for 22 h IVM increased the cAMP content of pre-pubertal oocytes, slowed meiotic progression during IVM and improved the rate of blastocyst formation. While the cAMP concentration of pre-pubertal oocytes was increased to levels similar to that of adult oocytes, rates of blastocyst formation remained lower, suggesting that additional factor(s) are required for oocyte maturation. This thesis also examined the follicle size cohorts that make up the 3-8 mm aspiration range on pig ovaries. The surface of pre-pubertal ovaries contained around double the number of 3 mm follicles compared with adult ovaries. Blastocyst development of pre-pubertal oocytes increased with increasing follicle size and was highest using oocytes from 5-8 mm follicles, while adult oocytes from all follicle size cohorts displayed similar high rates of blastocyst formation. The interaction between follicle size and cAMP content in pre-pubertal oocytes was examined next. Cumulus-oocyte complexes (COCs) from 3 mm follicles accumulated less intra-oocyte and inter-COC cAMP and displayed reduced cumulus expansion compared with COCs from 5-8 mm follicles. While dbcAMP treatment increased the cAMP content of oocytes from 3 mm follicles, it had no effect on the cAMP content of the whole COC. These findings suggest that inadequate levels of intra-oocyte cAMP during IVM contribute to the low developmental competence of pre-pubertal oocytes from 3 mm follicles, suggesting that cAMP transfer, production or degradation processes are incomplete. Analysis of steroid content from different follicle size cohorts revealed that the progesterone content of prepubertal follicular fluid (FF) increased with increasing follicle size, yet overall was lower than that of adults. This suggests that differences may exist in the gonadotropinstimulated steroidogenic activity of granulosa cells of pre-pubertal COCs from different follicle sizes. Since progesterone secretion did not differ between pre-pubertal and adult COCs, it appears that the downstream pathway from the granulosa cell response rather than the actual quantity of progesterone is important for subsequent maturation processes. These studies then examined gap junction communication (GJC) within the pre-pubertal COC during IVM to examine whether the positive effects of increasing follicle size and dbcAMP on intra-oocyte cAMP levels relates to improved cAMP transfer between the cumulus cell layer and oocyte. Cumulus cell-oocyte GJC during IVM was maintained for a longer period in pre-pubertal COCs from 3 mm follicles than in those from 5-8 mm follicles. Treatment with dbcAMP had minimal effect on GJC in either COC type, thus the dbcAMP-induced increase in intra-oocyte cAMP levels appears independent of GJC. Differences in GJC during IVM together with the COCs ability to increase intraoocyte cAMP levels during IVM, suggests that differences may exist in the quantity of gonadotropin receptors, which are responsible for cAMP production, within the cumulus layer of COCs from 3 mm compared with 5-8 mm follicles. In conclusion, this thesis has demonstrated that an increase in intra-oocyte cAMP is necessary during maturation for completion and synchronisation of maturation and high developmental competence of the pig oocyte. Comparison of 3, 4 and 5-8 mm follicle sizes in the pre-pubertal pig, as described here, provides an excellent model for further investigation into the role of cAMP and the other factors required for co-ordination of oocyte nuclear and cytoplasmic maturation and subsequent embryo production. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297309 / Thesis (Ph.D.) -- School of Paediatrics and Reproductive Health, 2007
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Screening soybean genotypes for high temperature tolerance by in vitro pollen germination, pollen tube length and physiological techniquesSalem, Mohammed A., January 2005 (has links)
Thesis (Ph.D.) -- Mississippi State University. Department of Plant and Soil Sciences. / Title from title screen. Includes bibliographical references.
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Mood Disorders, Personality and Grief in Women and Men undergoing in vitro Fertilization TreatmentVolgsten, Helena January 2009 (has links)
Psychological problems are common in infertile women undergoing in vitro fertilization (IVF) treatment. The aim of this thesis was to determine the prevalence of psychiatric disorders, such as mood and anxiety disorders, and related risk factors and personality traits in women and men undergoing IVF. Participants were 1090 consecutive women and men, 545 couples, attending a fertility clinic in Sweden during a two-year period. The Primary Care Evaluation of Mental Disorders (PRIME-MD), based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), was used for evaluating mood and anxiety disorders. The participation rate was 862 (79 %) subjects. Any psychiatric disorder was present in 31 % of females and in 10 % of males. Major depression was prevalent in 11 % of females and 5 % of males. Only 21 % of the subjects with a psychiatric disorder had some form of treatment. A negative pregnancy test and obesity (BMI ≥ 30) were risk factors for mood disorders in women and the only risk factor for depression in men was unexplained infertility. Anxiety disorders were less common than in the general population and no IVF-related risk factors were identified. The Swedish universities Scales of Personality (SSP), a self-rating questionnaire, was used for evaluation of personality traits. High scores of personality traits related to neuroticism were associated with mood and/or anxiety disorders among both women and men. Another objective was to explore the experience of childlessness three years after unsuccessful IVF by a qualitative-approach, assessing data by interviews. Failure after IVF was experienced by women in terms of grief, whereas men took upon themselves a supportive role not expressing grief. A need for professional support and counselling in how to handle grief was described. An unstructured end after IVF treatment left unanswered questions. Three years after the end of treatment, men and women were still processing and had not adapted to childlessness, indicating the grieving process was unresolved.
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