Life Sciences Commons^™

Impact Of Cadmium Stress On Soil Virus Reproduction And The Persistence Of Viruses Under Abiotic Conditions, Zhibo Cheng

Doctoral Dissertations

Soil viruses are ubiquitous and greatly impact the structure and function of soil microbial communities, with their effects modulated by various environmental factors. This study investigates the inactivation of naturally occurring soil viruses in sterilized soil, as well as the effects of cadmium (Cd) exposure and carbon (C) and nitrogen (N) nutrient availability on the population dynamics of virus-host communities in agricultural soil.

Lab-scale slurry and unsaturated experiments were performed to examine virus inactivation in the absence of host bacteria in sterilized soil. In slurry experiments, virus abundance declined by over 90% after 10 days of incubation. The addition of …

Assessing The Effects Of The Spring Hunting Season Start Date On Wild Turkey Seasonal Productivity And Hunter Behavior, Joseph Quehl

Masters Theses

Many states throughout the Southeast have documented declines in wild turkey (Meleagris gallopavo) harvest and estimates of recruitment in poult-per-hen ratios. Wild turkey populations are driven by seasonal productivity, so the decline in these parameters may indicate a decline in the overall population. One hypothesis as to why we are seeing a reduction in productivity and a potential population decline is that the spring hunting season is disrupting the reproductive cycle by harvesting too many males before they have had the opportunity to breed, or by harvesting dominant males and disrupting the social hierarchy of the flock. Our …

Climate Impacts On North American Quail, Shelby M. Perry, Erin Moser, Jeffrey G. Whitt, Kelly S. Reyna

National Quail Symposium Proceedings

North America’s quail population trends are often linked to regional climate. Extreme climate events such as severe drought, hard freezes, or excessive winter precipitation can reduce quail populations by as much as 84%. Above-average spring and summer temperatures coincident with drought can reduce the laying season for quail by ≤60 days. Exposure of quail eggs to high temperatures during preincubation can initiate and alter embryonic development. Here, we review the impacts of extreme climate events and a changing climate on the survival, reproduction, and population trends of 6 North American quail species: California quail (Callipepla californica), Gambel’s quail …

Applying Multistate Mark-Recapture Models With State Uncertainty To Estimate Survival And Reproduction Of Quail, Rebekah E. Ruzicka

National Quail Symposium Proceedings

Obtaining unbiased estimates of vital rates and understanding how vital rates change in response to environmental stimuli are a continual pursuit of ecologists. Multistate mark-recapture (MSMR) models provide a flexible framework for evaluating dependent vital rates in a comprehensive analysis. For example, a bird must remain alive during breeding season to initiate a nest (i.e., transition from a nonbreeding to a breeding state); thus, the probability that a bird initiates a nest is dependent on the probability that it is still alive. Traditional MSMR models allow only for the estimation of survival, detection, and state transition parameters and depend on …

Survival, Movement, And Habitat Use Of Translocated Northern Bobwhite In Texas, Ricardo Cagigal Perez, Nova J. Silvy, Brian L. Pierce, Therese A. Catanach

National Quail Symposium Proceedings

For decades there has been a noticeable decline in northern bobwhite (Colinus virginianus; hereafter, bobwhite) populations. Few studies have assessed the survival of translocated bobwhite. We evaluated the effectiveness of reintroduction of bobwhite into the Texas (USA) Parks and Wildlife Department’s Gus Engeling Wildlife Management Area (GEWMA), where they had been extirpated but now have suitable habitat. Before reintroduction, GEWMA was surveyed (spring call counts) to make sure no bobwhite were present. Forty-six bobwhite were trapped from March–April 2019 in South Texas, banded, bled, radio-tagged, transported to GEWMA, and released. In addition, 17 bobwhite were trapped banded, bled, …

Breeding Season Survival And Reproduction In A High-Density Bobwhite Population: A Case Study, William E. Palmer, Shane D. Wellendorf, D. Clay Sisson

National Quail Symposium Proceedings

The demographic behavior of northern bobwhite (Colinus virginianus; hereafter, bobwhite) populations at high densities could provide important insights into why bobwhite populations fluctuate. Therefore, we documented breeding season demographics of bobwhites to understand how prebreeding density influenced reproductive effort and postbreeding density on an intensively managed property in Leon County, Florida, USA, 2002–2006. We estimated prebreeding bobwhite density each April using multi-observer strip-transects and postbreeding densities each November using covey call grid surveys. We radio-tagged 217 bobwhites in March and located bobwhites at least 5 days/week, 15 April–30 September to determine vital rates. Prebreeding density ranged from 1.5–8.6 …

A Study Of The Effect Of Physiological Stressors On Hypothalamic Regulation Of Reproduction Using An In Vitro System, Lisa L. Amelse

Doctoral Dissertations

Stressors have a negative impact on reproductive efficiency in humans and other animals, which has an economic cost due to infertility treatments for humans and reduced income for food producers. We wished to determine the molecular pathways by which metabolic disturbances and low-level inflammation impact the hypothalamic pituitary gonadal (HPG) axis using an in vitro model. To this end, we used the GT1-7 cell line, an immortalized line expressing the Kiss1R receptor that responds to kisspeptin stimulation with the release of GnRH to assess the impact of stressors on the GnRH-releasing cells. Additionally, we used the KTaV-3 and KTaR-1[A1] …

Aspects Of The Reproductive Biology And Growth Of The Mississippi Silvery Minnow, Hybognathus Nuchalis (Agassiz, 1855) (Teleostei: Cyprinidae) From The Pearl River, Louisiana., Arely Ramírez-García, Kyle R. Piller

Southeastern Fishes Council Proceedings

The reproductive biology and growth of the Mississippi Silvery Minnow, Hybognathus nuchalis, is described from multiple sites in the Pearl River, Louisiana. Individuals were collected from August 2011 to August 2012. Ovarian weights, expressed as a percentage of body weights, peaked in December. Size structure ranged from 29.0 to 60.0 mm SL for females and 25.0 to 56.0 mm SL for males. Mature ova were found from November to January. Females reached first maturity (L50) at 37.0 mm SL and L50 for males is at 41.0 mm SL. Sex ratio (females:males) is biased towards females (X²= 18.57 p …

Follicular Dynamics In Insulin Resistant Mares, Julio Cesar Prado

Masters Theses

Obesity and insulin resistance have been linked to prolonged interovulatory period, aberrations in the estrous cycle, and continuous reproductive activity during the non-breeding season. EMS has been determined to influence the intrafollicular environment of mare ovaries. In humans, insulin resistance has been linked to polycystic ovaries as part of Polycystic Ovarian Syndrome (PCOS). A study was conducted to determine 1) the impact of insulin resistance on follicle growth and size at ovulation, and 2) whether predicted ovulatory follicles respond to hCG administration in Insulin-resistant (IR) mares. Mares were selected for the study based on insulin sensitivity and separated into an …

Adipose Tissue's Potential Role As A Reproductive Or Lactation Endocrine Gland, Megan Gray Macdougal

Masters Theses

While adipose tissue secretes hormones related to nutrition and metabolism, a few studies have provided evidence suggesting a direct reproductive role from adipose-derived products. The goal of this study was to determine if adipose tissue serves as a reproductive or lactation endocrine gland. Adipose tissue was associated with the reproductive tract of mature female cows in two locations, mesosalpinx and mesometrium (tissues supporting the oviduct and uterus, respectively), in varying amounts. Using quantitative polymerase chain reaction on a non-descript pool of cows, LHβ, CGA, PRL, FST, and LEP transcripts were demonstrated to be present in mesosalpinx, subcutaneous, visceral, and peri-renal …