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Full-Text Articles in Life Sciences

Carrier Screening For Women Undergoing Elective Oocyte Cryopreservation (Eoc): A Look At Practice Among Reproductive Endocrinologists At An Academic Fertility Clinic, Melissa Manuelli May 2021

Carrier Screening For Women Undergoing Elective Oocyte Cryopreservation (Eoc): A Look At Practice Among Reproductive Endocrinologists At An Academic Fertility Clinic, Melissa Manuelli

Human Genetics Theses

Elective oocyte cryopreservation (EOC) is a process involving freezing and banking oocytes with the intention to be used in the future for pregnancy. Cryopreserving oocytes allows women to enhance their reproductive autonomy by reducing the effects of age-relatedfertility decline. Similarly, expanded carrier screening (ECS) completed prior to conception allows women to consider their full range of reproductive options including in-vitro fertilization (IVF) with preimplantation genetic testing (PGT), use of donor gametes, and prenatal testing and diagnosis. In this retrospective chart review, we examine carrier screening practices for 106 EOC patients, and an age-matched control group of 106 IVF patients who …


Multi-Generational Effects Of ∆9-Tetrahydrocannabinol Exposure On Gene Expression In Liver Tissue, Kayla Lovitt May 2020

Multi-Generational Effects Of ∆9-Tetrahydrocannabinol Exposure On Gene Expression In Liver Tissue, Kayla Lovitt

Honors Theses

Cannabis is the most commonly used, cultivated, and trafficked illicit drug worldwide. Increased availability and acceptance of cannabis and cannabinoid-containing products provide the necessity for understanding how these substances influence aging. In this study, zebrafish (Danio rerio) were exposed to concentrations of Δ9-tetrahydrocannabinol (THC) (0.08, 0.4, 2 µM) during embryonic-larval development, the effects on aging were measured 30 months later and in the offspring of the exposed fish (F1 generation. We observed results indicating a biphasic and hormetic effect. Treatment with the lowest concentration of THC significantly increased egg production, while higher concentrations resulted in impaired …


The Impact Of Heat Load On Cattle, Angela M. Lees, Veerasamy Sejian, Andrea L. Wallage, Cameron C. Steel, Terry L. Mader, Jarrod C. Lees, John B. Gaughan Jan 2019

The Impact Of Heat Load On Cattle, Angela M. Lees, Veerasamy Sejian, Andrea L. Wallage, Cameron C. Steel, Terry L. Mader, Jarrod C. Lees, John B. Gaughan

Department of Animal Science: Faculty Publications

Heat stress and cold stress have a negative influence on cattle welfare and productivity. There have been some studies investigating the influence of cold stress on cattle, however the emphasis within this review is the influence of heat stress on cattle. The impact of hot weather on cattle is of increasing importance due to the changing global environment. Heat stress is a worldwide phenomenon that is associated with reduced animal productivity and welfare, particularly during the summer months. Animal responses to their thermal environment are extremely varied, however, it is clear that the thermal environment influences the health, productivity, and …


Temperature And Polyunsaturated Fatty Acid’S Effect On Daphnia Magna Reproduction, Mark Albright Dec 2018

Temperature And Polyunsaturated Fatty Acid’S Effect On Daphnia Magna Reproduction, Mark Albright

Electronic Theses and Dissertations

Organisms adapt to their environments by adjusting their biochemistry and physiology; such adaptation is limited by resource availability and physiological constraints. The freshwater crustacean Daphnia magna inhabits a wide range of environments and must survive and reproduce within a range of temperatures. One limit to low-temperature adaptation is thought to be the availability of unsaturated fatty acids necessary to maintain proper fluidity of cellular membranes. D. magna maintained at 10 ºC on a diet poor in unsaturated fatty acids have been observed to produce clutches that fail to develop. However, this has not been observed on a diet rich in …


Triennial Reproduction Symposium: Looking Back And Moving Forward—How Reproductive Physiology Has Evolved, Deb L. Hamernik, Andrea S. Cupp, John S. Davis Jan 2018

Triennial Reproduction Symposium: Looking Back And Moving Forward—How Reproductive Physiology Has Evolved, Deb L. Hamernik, Andrea S. Cupp, John S. Davis

Department of Animal Science: Faculty Publications

In honor of the 50th anniversary of the Society for the Study of Reproduction (SSR), a Triennial Reproduction Symposium was cosponsored by SSR and the American Society of Animal Science (ASAS). The Society for the Study of Reproduction was formed in 1967 when a group of reproductive biologists that were members of ASAS met with physician scientists and decided to organize a new scientific society. The goal of SSR was to promote the study of reproduction by fostering interdisciplinary communication among scientists, holding conferences, and publishing meritorious studies. Today after its 50th anniversary, the mission for SSR is to harness …


Determining The Reproductive Patterns Of The Titan Acorn Barnacle (Megabalanus Coccopoma) In Its Introduced Range, Isabel L. Moran Ms. Jan 2017

Determining The Reproductive Patterns Of The Titan Acorn Barnacle (Megabalanus Coccopoma) In Its Introduced Range, Isabel L. Moran Ms.

Honors College Theses

Invasive species are a significant conservation concern given their contribution to native species decline. The barnacle, Megabalanus coccopoma, is a common invasive species in tropical and subtropical regions of both the Pacific and Atlantic oceans. Little is known about the life history and ecology of M. coccopoma, and data on reproductive biology could provide valuable insight into its propensity to establish introduced populations. Most species of barnacle (including M. coccopoma) are hermaphroditic, but self-fertilization is rare in species studied to date. A recent genetic study of introduced M. coccopoma populations in the southeastern US showed high levels of …


Application Of Genomic Technologies To Study Infertility, Nicholas Rui Yuan Ho May 2016

Application Of Genomic Technologies To Study Infertility, Nicholas Rui Yuan Ho

Arts & Sciences Electronic Theses and Dissertations

An estimated one in eight couples in the United States are diagnosed with infertility. There is a significant genetic contribution to infertility, with estimates of heritability ranging from 0.2 to 0.5. We know surprisingly little about the genetic causes, with only slightly more than a hundred genes known to cause human infertility. I have been translating recent advances in genomics to study infertility in a more efficient manner, in order to improve our knowledge of the genetic causes. By using high throughput genomics and proteomics datasets from other groups, I was able to feed that into a machine learning algorithm …


Analysis Of Long-Term Selection (28 Generations) For Reproduction, Growth, And Carcass Traits In Swine, Wan-Ling Hsu Jan 2015

Analysis Of Long-Term Selection (28 Generations) For Reproduction, Growth, And Carcass Traits In Swine, Wan-Ling Hsu

Wan-Ling Hsu

The objectives were 1) to estimate responses from 28 generations of selection for increased pigs born alive (BA) with additional selection for increased 180 d weight (WT) and longissimus muscle area (LMA) and decreased backfat (BF) in the last eight generations, 2) to estimate genetic parameters for an array of traits, and 3) to investigate whether a plateau in response for BA has occurred. All lines were derived from the same Large White/Landrace composite population. Index selection for ovulation rate and embryo survival (G0-11) was initiated in L2 in 1981; L1 was selected randomly control line for L2 (G0-23). L2 …


Genome-Wide Prediction Of Age At Puberty And Reproductive Longevity In Sows, Julie Kathleen Tart, Rodger K. Johnson, Justin W. Bundy, N. N. Ferdinand, A. M. Mcknite, Jennifer R. Wood, Phillip S. Miller, M. F. Rothschild, Matthew L. Spangler, Dorian J. Garrick, Stephen D. Kachman, Daniel C. Ciobanu Aug 2013

Genome-Wide Prediction Of Age At Puberty And Reproductive Longevity In Sows, Julie Kathleen Tart, Rodger K. Johnson, Justin W. Bundy, N. N. Ferdinand, A. M. Mcknite, Jennifer R. Wood, Phillip S. Miller, M. F. Rothschild, Matthew L. Spangler, Dorian J. Garrick, Stephen D. Kachman, Daniel C. Ciobanu

Department of Animal Science: Faculty Publications

Traditional selection for sow reproductive longevity is ineffective due to low heritability and late expression of the trait. Incorporation of DNA markers into selection programs is potentially a more practical approach for improving sow lifetime productivity. Using a resource population of crossbred gilts, we explored pleiotropic sources of variation that influence age at puberty and reproductive longevity. Of the traits recorded before breeding, only age at puberty significantly affected the probability that females would produce a first parity litter. The genetic variance explained by 1-Mb windows of the sow genome, compared across traits, uncovered regions that influence both age at …


Genome-Wide Association Analyses Of Sow Reproduction And Lifetime Productivity, Daniel Ciobanu Feb 2013

Genome-Wide Association Analyses Of Sow Reproduction And Lifetime Productivity, Daniel Ciobanu

Department of Animal Science: Faculty Publications

Concurrent with increased prolificacy, high sow death losses and replacement rates are serious economic and welfare issues facing producers. Reproductive failure is the most frequent reason for culling sows. Lifetime productivity is characterized by moderate heritability and high phenotypic variance and, as a result, substantial genetic variation is expected to exist in most populations. Traditional selection for sow reproductive longevity results is ineffective due to low heritability and late expression of the trait. The primary goal of this research project was to identify DNA markers associated with reproductive and sow lifetime productivity that can be used in nucleus herds to …


A Comprehensive Research Framework For Geographic Parthenogenesis In Whiptail Lizards (Genus Aspidoscelis), Adam Leland Jan 2013

A Comprehensive Research Framework For Geographic Parthenogenesis In Whiptail Lizards (Genus Aspidoscelis), Adam Leland

UNLV Theses, Dissertations, Professional Papers, and Capstones

One of the most compelling topics in biology has been the ubiquity of sexual reproduction in living organisms. Because the ecological and evolutionary advantages of sex are well founded, those organisms that reproduce asexually remain enigmatic. Parthenogenesis, the clonal reproduction of an all-female species without the need for males, is a relatively common form of asexual reproduction in vertebrates, and has been subject of numerous academic investigations. Many parthenogenic organisms also share aspects of their geographic distributions, such as inhabiting higher latitudes, higher altitudes, islands or island-like habitats, xeric environments, and marginal, disturbed or ecotonal habitats relative to their sexual …


Analysis Of Long-Term Selection (28 Generations) For Reproduction, Growth, And Carcass Traits In Swine, Wan-Ling Hsu May 2011

Analysis Of Long-Term Selection (28 Generations) For Reproduction, Growth, And Carcass Traits In Swine, Wan-Ling Hsu

Department of Animal Science: Dissertations, Theses, and Student Research

The objectives were 1) to estimate responses from 28 generations of selection for increased pigs born alive (BA) with additional selection for increased 180 d weight (WT) and longissimus muscle area (LMA) and decreased backfat (BF) in the last eight generations, 2) to estimate genetic parameters for an array of traits, and 3) to investigate whether a plateau in response for BA has occurred. All lines were derived from the same Large White/Landrace composite population. Index selection for ovulation rate and embryo survival (G0-11) was initiated in L2 in 1981; L1 was selected randomly control line for L2 (G0-23). L2 …


Identification Of Markers Associated With Sow Lifetime Productivity For Whole Genomic Selection, Daniel Ciobanu Jun 2010

Identification Of Markers Associated With Sow Lifetime Productivity For Whole Genomic Selection, Daniel Ciobanu

Department of Animal Science: Faculty Publications

Sows are more productive today than ever before. However, concurrent with increased prolificacy, high sow death losses and replacement rates are serious economic and welfare issues facing producers. Reproductive failure is the most frequent reason for culling sows. Length of productive life is moderately heritable and has high variance; thus, substantial genetic variation is expected to exist in most populations. Genetic improvement in the swine industry occurs from selection in nucleus herds and is then transmitted through the breeding pyramid in the multiplication process. Thus, it is critical to identify selection methods that can be applied in nucleus herds that …


Proactive Procreation : Ethical Implications Of New Genetic Technologies For Parental Obligations To Future Offspring, L Syd M. Johnson Jan 2009

Proactive Procreation : Ethical Implications Of New Genetic Technologies For Parental Obligations To Future Offspring, L Syd M. Johnson

Legacy Theses & Dissertations (2009 - 2024)

This dissertation examines the ethical implications of recent genetic innovations, particularly preimplantation genetic diagnosis, for the obligations and duties of parents to future children. I critique common but uncompelling objections to the use of genetic information, diagnosis, and technology to influence the characteristics of future offspring, and conclude that genetic selection and enhancement are not different in kind or degree from other means of selection, direction, and enhancement that parents engage in to shape the lives of their children. Procreation is morally risky -- it risks imposing substantial burdens on persons who would not otherwise have to bear those burdens, …


Natural History And Karyology Of The Yucatán Vesper Mouse, Otonyctomys Hatti, Hugh H. Genoways, Robert M. Timm, Mark D. Engstrom Jan 2005

Natural History And Karyology Of The Yucatán Vesper Mouse, Otonyctomys Hatti, Hugh H. Genoways, Robert M. Timm, Mark D. Engstrom

University of Nebraska State Museum: Mammalogy Papers

Seventeen specimens of the rare Yucatán vesper mouse, Otonyctomys hatti, are now known from Belize, Guatemala, and the Mexican states of Campeche, Quintana Roo, and Yucatán. We herein report a second specimen of O. hatti, from Belize, extending the known geographic range of the species 95 km to the southeast in the country. This is the first location at which O. hatti has been taken sympatrically with the Central American vesper mouse, Nyctomys sumichrasti. We also report data on three additional specimens of O. hatti from Campeche. Nyctomys and Otonyctomys share similar habits and habitat requirements, and …