No description available.

No description available.

No description available.

In Poecilia latipinna size-specific reproductive and survivorship patterns were correlated with changes in habitat availability. Of the numerous physical, chemical, and biological parameters associated with a reduction in available habitat, probably the most important was reduced food availability. Large (old) females, theoretically with a low reproductive value, allocated energy to reproduction regardless of habitat and, presumably, food availability. When reproductive activities were initiated in March, habitat availability was modest. In association with a severe reduction in available habitat in April, large females were subject to a substantial loss of body weight during the yolk-loading phase of the reproductive cycle. This loss, primarily of somatic tissue, was very costly and heavy mortality ensued. Habitat availability increased during late May and June and survivorship increased. By August the somatic condition of large females had improved significantly. As in April, yolk-leading resulted in a loss of body weight; however, the loss consisted of approximately 70% lipid. Although the cost was lower than April, the necessity of subsidizing reproduction with somatic tissue may account for the slight reduction in survivorship observed in September. Smaller (younger) females, theoretically with a higher reproductive value, allocated energy to reproduction in response to increases in habitat, and presumably food availability. This response was in the form of an increased number of small reproducing females and was not evident until the month following the increase in available habitat. In contrast to large females, reproductive activities among small females were initiated in April. In association with a severe reduction in habitat availability, small females were subject to a loss of dry weight during yolk-loading, which consisted of approximately 44% lipid. The cost of reproduction was reduced and survivorship improved relative to the large females. Despite an increase in available habitat in June, small females curtailed reproduction in favor of survival and increased fecundity afforded by a greater body size. By early August an increase in reproductive activities was evident among small females. The somatic condition of these females was significantly improved in comparison to April females. In contrast to large August females, small females did not subsidize reproduction with somatic tissue. The change in body weight was attributable to a loss of lipid. By early September the available habitat had increased dramatically. In comparison to August, the high number of small reproducing females suggested the response to improved conditions may be rapid. Changes in food availability and, thus the total energy budget (lower in spring, higher in the summer and fall) and the associated cost of reproduction (higher in spring, lower in fall) from April to September were not reflected by changes in fecundity. It appeared that under the conditions that prevailed during this study, a female that made a commitment to reproduction produced a size-specific brood of a fixed quality regardless of food availability and reproduction cost. If a female was able to assimilate excess energy during the gestation period, that energy was allocated in maintenance (i.e. repaying any somatic debt) and growth.

Endometriosis is an estrogen-dependent disease that is characterized by the growth of endometrial tissue outside of the uterine cavity. The most common endometriotic lesions are ovarian endometrioma, peritoneal lesions, and deeply-infiltrating endometriosis. Ten percent of women in reproductive age are affected, a gross underestimate due to the delay in diagnosis and non-specific symptoms. The etiology of endometriosis is not well understood, making diagnosis difficult, and treatments suboptimal. Currently, laparoscopic surgery is the gold standard for diagnosis, however this method is invasive, costly, and physicians are often reluctant to send their patients to surgery without certainty of disease. It is therefore a research priority to identify a minimally-invasive biomarker for endometriosis. Over the years, the search for a biomarker has shifted from a single circulating biomarker, to a panel of circulating biomarkers, and finally to the advent of newer technologies. The studies of proteomics, genomics, phenomics, and metabolomics have shown some promise thus far. MicroRNAs, a discovery of genomics, are short, non-coding RNA strands that regulate mRNA expression by silencing or degrading the transcript. The dysregulation of miRNAs have been shown to contribute to the pathology of many gynecological conditions, and have shown to be dysregulated in endometriosis. To date however, results have been underwhelming due to differences in methodologies and failure to consider endometriosis as a heterogeneous disease. Three miRNAs were studied based on their prevalence in the literature (miR-9, -21, and -424), and three others (miR-10a, -10b, and -204) were measured based on their association with BDNF. In the current study, miR-204 expression was significantly lower (p=0.0016) in the eutopic endometrium of women with endometriosis compared to controls. Relative expression of miR-21, miR-424, and miR-10b differed significantly (p<0.05) across lesion types in women with exclusively endometriomas, peritoneal or deep-infiltrating lesions. Corresponding BDNF expression in the lesion types were inversely correlated to miRNA expression suggesting these miRNA regulate BDNF and are implicated in endometriosis pathology. Due to the findings that miRNAs are differentially expressed between endometriotic lesions, this study also suggests that, different lesion types are biochemically distinct. / Thesis / Master of Health Sciences (MSc)

Pharmaceuticals are emerging surface water contaminants, and are manufactured, used, and released into environment in considerable amounts. Concerns have been raised due to the inherent potency and bioactivity of these molecules, which makes effects at low concentrations more likely. The ubiquitous presence and stability of pharmaceuticals brings up concerns about the frequency and length of exposures. However, the distribution and fate of these compounds in surface water bodies is not clear. There is limited information about the potential effects in non-target, especially aquatic, species vulnerable to cumulative or lifelong exposures. Carbamazepine (CBZ) and gemfibrozil (GEM) are two of the most frequently detected pharmaceuticals in surface water. This thesis examined sub-lethal adverse reproductive effects of chronic direct exposure of CBZ and GEM to F0 zebrafish and several generations of unexposed offspring; the effects of exposure on testicular steroidogenesis were also examined. Chronic exposure of zebrafish to CBZ and GEM reduced ex vivo production of 11KT in testes. In vivo, CBZ decreased reproductive output, 11-ketotestosterone (11KT), male courtship and aggression behaviours, and sperm morphology in F0 parents. The F1, F2 and F3 offspring of CBZ exposed males had lower reproductive output, altered courtship, aggression, sperm morphology and lower 11KT compared to fish from the unexposed lineage. The adverse effects persisted into the F3 generation which suggested transgenerational paternal effects. GEM decreased reproductive output in F0 parents and a reduction in 11KT, altered male courtship, aggression and sperm morphology. Unexposed F1 male offspring, but not other generations, had sub-lethal toxic effects from parental exposure. We therefore suggest that CBZ and GEM act as endocrine disruptors in fish and that chronic exposure may reduce male reproductive fitness. / Dissertation / Doctor of Philosophy (PhD) / Human pharmaceuticals reach aquatic environments through municipal wastewater. The bioactivity of pharmaceuticals at low concentrations has raised concerns about undesired effects in aquatic species like fish, which can experience chronic exposures. This thesis examined adverse reproductive effects of direct chronic exposure of carbamazepine and gemfibrozil to parental zebrafish and their un-exposed offspring for multiple generations. Exposure to both compounds reduced androgens and reproduction and altered behaviour, and sperm quality in males. Effects persisted in the unexposed offspring. Parental carbamazepine exposure impacted multiple generations. We suggest that carbamazepine and gemfibrozil may reduce male reproductive fitness by reducing male sex steroids.

No description available.

Pregnancy loss and calf death can cost dairy producers more than $230 million annually. While methods involving nutrition, climate, and health management to mitigate pregnancy loss and calf death have been developed, one potential influence that has not been well examined is the reproductive microbiome. I hypothesized that the microbiome of the reproductive tract would influence heifer fertility and calf gut microbial development. The objectives of this dissertation were: 1) to examine differences in phenotypes related to reproductive physiology in virgin Holstein heifers based on outcome of first insemination, 2) to characterize the uterine microbiome of virgin Holstein heifers before insemination and examine associations between uterine microbial composition and fertility related phenotypes, insemination outcome, and season of breeding, and 3) to characterize the various maternal and calf fecal microbiomes and predicted metagenomes during peri-partum and post-partum periods and examine the influence of the maternal microbiome on calf gut development during the pre-weaning phase. In the first experiment, virgin Holstein heifers (n = 52) were enrolled over 12 periods, on period per month. On -3 d before insemination, heifers were weighed and the uterus was flushed. Flush pH and glucose concentration were measured. Blood was collected from coccygeal vessels on d -3, 15, 18, 21, 24, 27, and 30 relative to insemination and serum progesterone concentration was measured. Ultrasound measurements of dominant follicle diameter and corpus luteum volume. Insemination outcome was determined on d 30 using ultrasound and pregnancy was checked on d 42, 56, 70, and 84. Heifers were clustered based on outcome of insemination at d 30 (not pregnant, NP30, n = 24; pregnant, PS30, n = 28), d 84 (not pregnant, NP84, n = 24; pregnant but lost before d 84, PL84, n = 2; successfully pregnant through d 84, PS84, n = 26). Differences in phenotypes were assessed based on insemination outcome at d 30 and d 84. Weight was greater in NP30 heifer than PS30 heifers. Progesterone was greater in PS30 and PS84 heifers than NP30 or NP84 heifers on d -3 and 18 to 30 and CL volume was greater in PS30 and PS84 heifers than NP30 and NP84 heifers on d 21 and 30. To summarize, traits related to pregnancy maintenance were different in virgin Holstein heifers based on first insemination outcomes and might be able to be used to predict heifer reproductive performance. Uterine flushes were examined in a subset of heifers (n = 28) based on insemination outcome and period. This subset was also clustered based on season (spring, n = 3; summer, n = 12; fall, n = 8; winter, n = 5). From this subset of heifers, DNA was extracted from uterine flush and 16S amplicons of the V4 region underwent 250 paired-end sequencing via Illumina NovaSeq 6000. Filtered reads were clustered into operational taxonomic units using a 97% similarity and assigned taxonomy using the SSURNA Silva reference version 132. Alpha and beta diversity were measured and differences in alpha and beta diversity measurements were analyzed based on insemination outcome at d 30 or d 84 and season of breeding. Differential abundance analyses were performed at the phylum and genus taxonomic ranks based on insemination outcome at d 30 or d 84 and season of breeding. Bacterial richness was reduced in PL84 heifers than NP84 and PS84 heifers and reduced in heifers bred in spring than those bred in other seasons. Bacterial community structure was different based on insemination outcome at d 30 and d 84 using unweighted Unifrac distances and was different based on season of breeding using weighted Unifrac distances. We observed an increase of Bacteroidetes in PS30 and PS84 heifers compared to NP30 and NP84 heifers. Ureaplasma and Ruminococcus had an increased abundance in PS30 and PS84 heifers than NP30 and NP84 heifers, while Afipia and Gardnerella had an increased abundance in NP30 and NP84 heifers than PS30 and PS84 heifers. Prevotella and Ruminococcus had a reduced abundance in summer bred heifers than winter bred heifers. Proteobacteria had a moderate negative correlation with -3 d progesterone (rp = -0.42) and Actinobacteria had a moderate negative correlation with fetal growth rate (rp = -0.66). Uterine microbiome of virgin Holstein heifers differed based on insemination outcomes and season of breeding and might be a new phenotype to indicate heifer fertility. In the second experiment, multiparous Holstein cows (n = 12) were placed in individual box stalls 14 d before expected calving. Sterile swabs were used to collect samples from the posterior vagina of the dam approximately 24 h before calving, dam feces, dam oral cavity, and colostrum within 1 h after calving, and cotyledonary placenta within 6 h after calving. Calves (n = 12; bulls = 8, heifers = 4) were isolated immediately after parturition to prevent environmental contamination. Colostrum was fed to calves using a clean bottle that was assigned to the calf for the duration of the study. Calves were individually housed for 60 d until weaning. Sterile swabs were used to collect calf fecal samples at birth, 24 h, 7 d, 42 d, and 60 d of age. A subset of calf-dam pairs (n = 6; bulls = 3, heifers = 3) were selected and DNA was extracted from all samples. Amplicons covering V4-V5 16S rDNA regions were generated using extracted DNA and sequenced using 300 bp paired end sequencing via Illumina MiSeq. Sequences were aligned into operational taxonomic units using the 97% Greengenes reference database. Spearman correlations were performed between maternal and calf fecal microbiomes. Negative binomial regression models were created for genera in calf fecal samples at each time point using genera in maternal microbiomes. Metagenomes were predicted, collapsed into gene pathways and differences in predicted metagenomes were analyzed within STAMP (Statistical Analysis of Metagenomic Profiles). We determined that Bacteroidetes dominated the calf fecal microbiome at all time points (relative abundance ≥ 42.55%) except for 24 h post-calving, where Proteobacteria were the dominant phylum (relative abundance = 85.10%). Colostrum and placenta had low diversity within samples and clustered independently from fecal samples. Each maternal microbiome was a significant predictor for calf fecal microbiome during at least 2 time points. Genes for infectious disease and neurodegenerative disease were greater in colostrum and 24 h calf fecal samples compared to other samples. Results indicated that no one maternal microbiome was a major influence on calf fecal microbiome inoculation and development. Instead, calf fecal microbial development stems from various maternal microbial sources. Overall, the reproductive microbiome was predictive of heifer pregnancy outcomes and calf fecal microbial development. The virgin heifer uterine microbiome could be used to predict fertility and adaptation to heat stress, but further research including a larger group of pregnancy loss is needed. Maternal microbiomes from the reproductive tract, colostrum, oral cavity, and feces could all be used to predict calf microbial development, but more research including other maternal microbiomes and environmental microbial contributions is needed. However, the results from this dissertation indicate reproductive microbiome composition is a trait that might be predictive of dairy cattle performance. / Doctor of Philosophy / The ability of a cow to become pregnant and a calf to thrive after birth are crucial to successful dairy farm operations. Recent evidence in humans has shown bacteria in the reproductive tract can influence maternal fertility and the bacterial community of newborns, an indicator of early health. This same relationship might exist in dairy cattle. I propose that specific traits related to fertility and the bacterial community in the reproductive tract of dairy cattle influences their ability to become pregnant and influences the bacterial community developing in calves after their birth. In my first experiment, I collected samples of uterine fluid from cattle that had never been pregnant before the first time they would be bred. I also collected blood samples before and after breeding to measure hormone levels as well as measurements of portions of reproductive tract using an ultrasound. Using a specific portion of DNA that is similar across all bacteria, I identified the bacterial community in the collected uterine fluid. Cattle were grouped based on breeding outcome (not pregnant, pregnant but lost, or kept pregnancy) and season of breeding. Differences in various traits and bacterial communities were examined based on breeding outcome and season. I found that traits like hormone levels in the blood and size of structures on the reproductive tract, and uterine bacterial community all differed based on breeding outcome. We also found that uterine bacterial community also differed based on season of breeding. These results could be used to predict if a cow will become pregnant before they are ever bred, but more research is needed. In our second experiment, we collected samples from the reproductive tract, milk, mouth, and feces of cows immediately after they gave birth. We then collected samples from their calves right at birth as well as at various time points during their early life. Using the same section of DNA used during the first experiment, we identified the bacterial community composition from the various maternal and calf samples. We then identified correlations between maternal and calf bacteria and used a mathematical model to see if the maternal bacteria could predict bacteria in the calf. We found that the various maternal bacteria could predict calf bacteria throughout the calves early life. While an experiment using a larger group of cows and calves is needed, our results indicate that the maternal bacteria could be used to predict calf bacteria and may help determine which calves are more likely to become sick than others. Overall, we found that the bacteria in the reproductive tract could be used to predict ability to become pregnant and calf bacterial development. The incorporation of this bacterial community as a trait on farms could help reduce pregnancy loss and calf illness, but further research examining how the bacteria interact with the animal is needed.

This dissertation examines how reproductive efficiency can be improved through dietary intervention. The use of diet to enhance reproduction is theoretically a low-cost and low-input method that will co-align with reproductive technologies' beneficiary effects. Ideally, with improved nutrition intervention, these technologies will become more feasible and practical to producers. The first study examines the diet nutrient composition and its relative interactions on days to ovulation postpartum, overall pregnancy rates, and pregnancy at first AI in cattle. Most notably, the highest predicted overall pregnancy rate for multiparous cows was observed at high crude protein (CP), moderate non-structural carbohydrates (NSC), Low neutral detergent fiber (NDF) and high ether extract (EE). Additionally, the highest predicted pregnancy at first AI rate was when CP was high, moderate NSC, high NDF, and low EE. The second study examines the impact that a high starch diet may have on reproductive hormones, follicular growth, and pregnancy rates. The high starch diet tended to have a greater placental associated glycoprotein concentration, a greater number of large follicles on the day of breeding and a 20% numerically greater overall conception rate. The high fat diet did exhibit a greater number of medium sized follicles on the day of breeding. There were no observed differences in progesterone concentrations between the two treatment groups. The final study examines the effect that a higher starch diet might have on follicular development, CL growth and size, reproductive hormones, and insulin like growth factor binding proteins -2, -3, -4, -5, and pregnancy associated plasma protein A gene expression in granulosa cells. The experimental group that received the diet greater in starch exhibited a greater concentration of plasma IGF-1, greater number of large follicles on the dates that insemination would occur in a TAI situation, and a lower amount of days to reach a dominant follicle at the diameter of ≥ 10mm. Additionally, the high fat diet did exhibit a greater concentration of progesterone. Although, no statistical differences were observed in the granulosa cell gene expression and corpus luteum size. The feeding technique here may provide producers insight into non-expensive and straightforward ways to improve their reproductive efficiency and, ideally, adopt reproductive technologies in harmony with dietary intervention. / Doctor of Philosophy / Improving reproductive efficiency in both beef and dairy cows is essential to continually improve meat and milk production to meet the growing global demand for animal food products. In both beef and dairy operations, the goal is to produce one healthy calf per cow per year. However, each operation type faces unique challenges which, at present, often preclude achieving this goal. Intensive genetic selection for milk production has resulted in inadvertent selection against reproductive efficiency in the dairy industry. In the beef industry, the production conditions and tight profit margins mean that producers are often hesitant to use assisted reproductive technologies like estrus synchronization or artificial insemination, which may help improve reproductive efficiencies. On account of these challenges, there is a clear need for supportive tools and technologies which can be applied within the beef and dairy industries to improve the reproductive efficiencies of these production systems. One possible strategy that could be employed to improve reproductive efficiency within the beef and dairy industries is nutritional manipulation. Although there are mixed results within the literature regarding how dietary manipulation can be leveraged to affect reproductive outcomes, feed supplementation is typically a strategy readily leveraged by beef and dairy producers for various production outcomes. As such, dietary manipulation may be a promising method to improve reproductive efficiency, assuming discrepancies among studies within the literature can be reconciled to provide feeding recommendations to improve reproduction. One strategy to evaluate commonalities among literature data is the use of meta-analysis. Our first study leveraged meta-analysis to evaluate how diet composition and its interactions with parity, genetics, and housing situation affect reproductive outcomes. This study found that reproduction is affected by complex interactions among diet, management, genetics, and time. Thus, leveraging nutrition to improve reproductive efficiency will require precise identification of the correct supplement for the correct animals, based on their age and management conditions. Experimental work to confirm the efficacy of different nutritional modulation strategies will be essential to confirm such strategies before widespread use. Rather than experimentally evaluating an exhaustive listing of strategies to improve reproductive efficiency, confirmation experiments will be more efficient if they evaluate dietary approaches that appeared successful under most conditions simulated in the meta-analysis. In our meta-analysis, supplementation of non-structural carbohydrates (NSC) and ether extract (EE) fairly consistently improved reproductive outcomes when compared with crude protein (CP) and neutral detergent fiber (NDF) supplementation, which had more mixed results. Current literature on these feed supplements is often confounded with energy intake, meaning that it is difficult to discern whether the consistency in response reflects consistent benefit of added energy or unique benefits of these energy-providing substrates. As such, we designed an experiment to evaluate the effect of isoenergetic supplementation of EE and NSC within the diets of grazing Angus crossbred beef heifers to evaluate the effects on reproductive outcomes. Responses of interest included progesterone concentrations, pregnancy rates, placental-associated glycoprotein concentrations, and follicle size and number. Supplementation of NSC resulted in lower plasma progesterone and a significantly lower number of medium follicles on the day of breeding, relative to supplementation with fat. However, heifers supplemented with NSC also had elevated placental-associated glycoprotein concentrations, numerically increased conception rates, and a greater number of large follicles on the day of breeding when compared with the heifers supplemented with fat. As such, the data suggest the NSC diet promoted the maturation of large follicles, which may support improved conception rates. The EE diet promoted elevated progesterone concentrations, but did not appear to support the maturation of medium to large follicles, likely accounting for the numerically lower conception rates. Because heifers are well acknowledged to differ from cows due to their energy requirements, it is useful to also evaluate the efficacy of these dietary treatments in mature cows to assess the consistency of responses. Toward that goal, the objective of our second study was to compare supplementation of high NSC or high EE feeds to mixed-breed, non-pregnant, multiparous beef cows when evaluating reproductive outcomes. The results of these supplementation strategies were similar to those identified within the heifer trial. The group consuming the high EE supplement had elevated plasma progesterone concentrations. The group consuming the high NSC supplement had a greater number of large follicles on the days of GnRH administration. There were no differences in gene expression of aspirated granulosa cells between the two groups. The consistency of results between the heifer and cow studies suggest that supplementation with high NSC or high fat supplements may consistently affect cows, irrespective of physiological stage. As such, further work to titrate the minimum required supplementation levels to assess the possible economic returns of this approach to optimizing reproductive efficiency. Our studies concluded that reproductive efficiency can be enhanced through dietary manipulation in a manner independent of dietary energy intake. Additionally, the utilization of a propiogenic precursor such as a high NSC diet appears to support the maturation of follicles in cattle utilizing a timed artificial insemination estrus synchronization protocol, likely leading to improved pregnancy rates. As such, assessment of NSC supplementation for reproductive modulation may be a productive line of future work.

Otiorhynchus sulcatus (Fabricius) is a serious pest of various horticultural crops in the United States. Despite its economic importance, this pest remains very challenging to manage. Integrated Pest Management Program for O. sulcatus has not yet been implemented due to lack of accurate information on its ecology. Investigation of temperature-dependent development and reproduction of O. sulcatus was conducted to enable the prediction of stage emergence more accurately. Immature-development study at constant temperatures 11-30 oC showed that there was the difference in optimal temperature regime among immature stages, which suggests that temperature can play a role to adapt each stage to the different temperature condition of the season. By applying mathematical models, optimum temperature for the fastest development was estimated to be 27.5, 25.1, and 24.1 oC for eggs, larvae, and pupae, respectively. Temperature also significantly influenced the adult reproductive life history traits, including preovipositional period, ovipositional period, longevity, per capita egg production, and egg viability. At 27 oC or above, reproductive success of O. sulcatus was substantially impaired due to shortened longevity, delayed reproduction, and lowered egg viability. Endosymbiont bacteria Wolbachia infect many arthropod species and they may alter the reproduction of their hosts. I first documented that Wolbachia is highly prevalent in O. sulcatus populations in the United States. Given that two antibiotics (tetracycline and gentamicin) differing only in their efficacy against Wolbachia, results strongly support the hypothesis that Wolbachia may be required for normal egg development of O. sulcatus. Despite intensive insecticide application, O. sulcatus populations often remain at unacceptable levels. I ask whether sublethal dosages of newer insecticides, imidacloprid and thiamethoxam, influence offspring production of O. sulcatus adults and its progeny under laboratory conditions. Weevils that survived short-term exposure to sublethal dosages of imidacloprid and thiamethoxam produce viable offspring when they have access to insecticide-free leaves after the exposure. Toxicity test showed the potential of imidacloprid and thiamethoxam for the control of first-instars but not for the control of eggs. / Ph. D.