Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 16 of 16 for “"Plasma testosterone"”.
-
Seasonal Patterns of Plasma Testosterone Levels, Bite Force, and Locomotor Performance in Non-Territorial Male Lizards, Aspidoscelis Sexlineata
… however, remain unclear. The steroid hormone testosterone mediates numerous traits associated with reproduction in male vertebrates and has been hypothesized to mediate variation in performance. This study examined seasonal patterns of circulating testosterone, morphology, bite force, and …
-
Fundulus grandis Response to Exogenous LH Injection.
… measured through the reproductive parameters of plasma sex steriod levels (estrogen for the female and testosterone for the male animals) as well as gonadalsomatic indexes, GSI. Females were also evaluated on the microscopic and macroscopic appearance of the ovary. Injections of ovine luteinizing …
-
Benzo[a]pyrene effects on Fundulus heteroclitus reproductive endpoints
… In males, both gonadosomatic index (GSI) and plasma testosterone concentrations were significantly reduced compared to controls by 10 μg/L BaP. An increase in empty follicles and interstitial fibrosis was observed by histopathological examination of testes. Other biomarkers including male …
-
The Effects of VO2max on Levels of Testosterone as Males Age
Purpose: The reduction of Testosterone secretion by the gonads is “hypogonadism” and development of age-related hypogonadism is known as “late-onset hypogonadism”. Late-onset hypogonadism is characterized by issues such as osteoporosis, Alzheimer’s disease, frailty, obesity, cardiac failure and …
-
Investigating the Effects of Vinclozolin on Reproduction in Three Generations of Sigmodon Hispidus
… groups, and between genders. Free and total plasma testosterone levels were compared. Sperm production in the seminiferous tubules of the testes (collected during necropsy, embedded, sectioned, and placed on slides for examination) allowed a sperm index for comparison. Other comparisons …
-
Evaluation of a plasmid delivery system for production of GnRH and GHRH in the horse and goat
… sites. Expression of SEAP, measured from jugular plasma samples, indicated muscle specificity for uptake and expression of the plasmid. Concentrations of SEAP were greatest (P < 0.05) after pectoralis injection, which was chosen as the site for electroporation in subsequent studies. In a second …
-
The Reproductive Cycle of Sceloporus undulatus From Alabama Corresponding Plasma Steroid Levels and Comments on Reproductive Variation.
… recrudescence later than Missouri S. undulatus. Plasma testosterone levels in the males peaked soon after emergence from brumation, declined during spring breeding, and rose again in the fall. These changes were concomitant with changes in testis mass and spermatogenesis.Females emerged from …
-
Thermoregulation, hibernation and reproduction in the South African hedgehog Erinaceus frontalis A. Smith
… ranged from 1 - 11 (n = 6). Seasonal changes in plasma testosterone and plasma progesterone levels during a one year period were determined. From September to January the arculating levels of testosterone were high while low levels were recorded from February to June. Testicular activity resumed …
-
Reproductive Biology and Conservation Genetics of the Alligator Snapping Turtle (Macrochelys Temminckii)
… carapace length, plastron-to-vent length, and testosterone levels were used to determine gender of smaller individuals. To ensure accurate sexual assignment when studying M. temminckii, data from multiple methods (morphological measurements, ultrasonography, testosterone levels, and, …
-
Ultimate and Proximate Explanations of Helping Behavior in the Red-cockaded Woodpecker (Picoides borealis)
… breeding and helping behavior by measuring plasma testosterone (T) and prolactin (PRL) concentrations in female breeders, male breeders, and male helpers during different stages of the reproductive cycle. Among male breeders and helpers, T is low during the nonbreeding stage, peaks during …
-
Life history and physiological ecology of the lizard, Cordylus Giganteus
… deferens for seven to eight months. A bimodal plasma testosterone profile is reported, consistent with spermiogenesis in autumn and mating behaviour in spring. C. giganteus feeds during 8 months of the year and prefer Coleoptera as prey. Fat bodies are utilized for winter maintenance and …
-
Reproductive Parameters of Nesting <em>Caretta caretta</em> on Georgia's Barrier Islands
… due to underestimating female nesting fecundity. Plasma steroid levels and ultrasonography were used to determine the population trends and nesting patterns for female <em>C. caretta</em> along Georgia's barrier islands. The reproductive status of nesting <em>C. caretta</em>was assessed at Wassaw …
-
Acute Pro-inflammatory Immune Response Following Different Resistance Exercise Protocols in Trained Men
… by the level of receptor expression on the plasma membrane of the monocyte, as well as the secretion of their cognate ligands from tissue resident cells. However, it remains unclear whether the innate pro-inflammatory immune response varies with different resistance training protocols, and …
-
Controlled cultivation techniques for the recovery of threatened fishes in Virginia
… enigmatic; motile sperm were observed only once. Plasma testosterone concentrations in males peaked just prior to the spawning season at 6.5 ng/mL, but levels were not correlated with male gonadosomatic values. Plasma 17β-estradiol levels in females peaked just prior to the spawning season at 15 …
-
The reproductive biology of two small southern African mammals, the spiny mouse, Acomys spinosissimus (Rodentia: Muridae) and the Eastern rock elephant-shrew, Elephantulus myurus (Macroscelidea: Macroscelididae)
… and volume of A. spinosissimus were smaller and plasma testosterone concentrations lower under short-day than long-day photoperiods which implies that male spiny mice are reproductively photoresponsive. In contrast, male E. myurus did not appear to be responsive to changing photoperiods and …
-
Lake Sturgeon (Acipenser fulvescens) Population Attributes, Reproductive Structure, and Distribution in Namakan Reservoir, Minnesota and Ontario
… was assessed during spring 2008 and 2009 using plasma testosterone and estradiol-17β concentrations. Age of lake sturgeon > 75 cm ranged from 9 to 86 years of age (n=533, mean=36 years). Using logistic regression analysis, I found that total annual precipitation was positively associated with …