Annual abundance of northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) fluctuates drastically in Texas, which complicates a quail manager’s ability to forecast quail abundance for the ensuing hunting season. The Texas Quail Index (TQI) was a 5-year citizen-science project that evaluated several indices of quail abundance and habitat parameters as predictors of quail abundance during the ensuing fall. I found that spring cock-call counts explained 41% of the variation in fall covey-call counts for all study sites in year 1–4, and 89% of the variation in year 5. Further investigation revealed that year 5 was a drought year and had a significantly lower percentage of juveniles in the hunter’s bag. These results suggest that during drought years, fall quail abundance is more predictable than during non-drought years and that low breeding success may be the reason. If these data are correct, quail managers should have a better ability to predict the declines of their fall quail abundance in the dry years. The TQI relied on citizen scientists (cooperators) to collect data. Since most (66.1%) cooperators dropped out of the program, and <8% of all data sets were complete, I surveyed the cooperators by mail to determine the rate and cause of cooperator decline and to identify characteristics of a reliable cooperator (i.e., one that did not drop out of the study). I found that cooperator participation declined earlier each year for year 1–4, and that year 5 demonstrated a steady trend with the least amount of cooperators. Most respondents who dropped out (61.5%) reported their motive for leaving was that it was too time consuming. I found no difference in mean cooperator demographics, satisfaction, or landownership goals between those respondents who dropped out and those that did not. However, 38% of those who dropped out were not completely satisfied with communication from TQI coordinators compared to only 15% of those who did not drop out, indicating that communication, or perhaps overall volunteer management, might have been improved. Future studies should maintain better communication with participants, require less time, and provide an incentive for retention.

No description available.

Craniofacial development requires orchestrated and complex interactions between multiple tissues of different origins. Cranial neural crest stem cells migrate from the dorsal neural tube into the frontonasal process and branchial arches where they ultimately form most of the skeletal structures and connective tissue of the craniofacial complex, as well as contributing neurons and glia to cranial ganglia. The timing and mechanism by which cranial neural crest cells progressively differentiate from multipotent stem cells into lineage restricted and terminally differentiating cell types has previously not been investigated. In addition, there are many deficits in our knowledge of the molecular controls regulating early development of neural crest cells within the branchial arches. Spatial and temporal changes in migratory and lineage potential in neural crest populations contributing to the developing first branchial arch and trigeminal ganglia were examined by back-transplanting cells from quail into chick embryos. Neural crest cells that had barely entered the first branchial arch had largely lost both the ability to localise to the trigeminal ganglia and neurogenic differentiation capacity but were still capable of long-distance migration. However, after a further 12 hours residence in the branchial arch, neural crest cells had lost long-distance migratory ability.

The common gecko, Hoplodactylus pacificus (Gray, in McCann (1955) ), is widely distributed throughout New Zealand. As yet no specific ecological study of this lizard has been published, though Sharell (1966) mentions habitat preferences and hibernation behaviour, and Whitaker (1968) has published some data for H. pacificus on Poor Knights Islands (mentioned in this report) and describes their observed foraging behaviour. In this study, carried out from late March through to May 1970, I have recorded information on snout-vent lengths, weights, individual movements, and habitat preference, and have also estimated the population density. This particular lizard does not seem to be active during the Autumn months and no observations of food preferences and foraging behaviour were able to be made.

Recent studies have established that yolk hormones of maternal origin have significant effects on the physiology and behavior of offspring in birds. Herrington (2012) demonstrated that an elevation of progesterone in yolk elevates emotional reactivity in bobwhite quail neonates. Chicks that hatched from progesterone treated eggs displayed increased latency in tonic immobility and did not emerge as quickly from a covered location into an open field compared to control groups. For the present study, three experimental groups were formed: chicks hatched from eggs with artificially elevated progesterone (P), chicks hatched from an oil-vehicle control group (V), and chicks hatched from a non-manipulated control group (C). Experiment 1 examined levels of progesterone with High Performance Liquid Chromatography/tandem Mass Spectroscopy (HPLC/MS) from prenatal day 1 to prenatal day 17 in bobwhite quail egg yolk. In Experiment 2, bobwhite quail embryos were passively exposed to an individual maternal assembly call for 24 hours prior to hatching. Chicks were then tested individually for their preference between the familiarized call and a novel call at 24 and 48 hours following hatching. For Experiment 3, newly hatched chicks were exposed to an individual maternal assembly call for 24-hrs. Chicks were then tested for their preference for the familiarized call at 24 and 48-hrs after hatch. Results of Experiment 1 showed that yolk progesterone levels were significantly elevated in treated eggs and were present in the egg yolk longer into prenatal development than the two control groups. Results from Experiment 2 indicated that chicks from the P group failed to demonstrate a preference for the familiar bobwhite maternal assembly call at 24 or 48-hrs after hatch following 24-hrs of prenatal exposure. In contrast, chicks from the C and V groups demonstrated a significant preference for the familiarized call. In Experiment 3, chicks from the P group showed an enhanced preference for the familiarized bobwhite maternal call compared to chicks from the C and V groups at 24 and 48-hrs after hatch. The results of these experiments suggest that elevated maternal yolk hormone levels in pre-incubated bobwhite quail eggs can influence auditory perceptual learning in embryos and neonates.

Feeding behavior is a complex trait that is regulated by various hypothalamic neuropeptides and neuronal populations (nuclei). Understanding the physiological regulation of food intake is important for improving nutrient utilization efficiency in agricultural species and for understanding and treating eating disorders. Knowledge about appetite in birds has agricultural and biomedical relevance and provides evolutionary perspective. I thus investigated hypothalamic molecular mechanisms associated with appetite in broilers, layers, chicken lines selected for low (LWS) or high (HWS) body weight, and Japanese quail, which provide a unique perspective to understanding appetite. Broiler-type chicks have been genetically selected for rapid growth and consume much more feed than do layer-type chicks which have been selected for egg production. Long-term selection has caused the LWS chicks to have different severities of anorexia while the HWS chicks become obese, thus making these lines a valuable model for metabolic disorders. Lastly, the Japanese quail have not undergone as extensive artificial selection as the chicken, thus this model may provide insights on how human intervention has changed the mechanisms that regulate feeding behavior in birds. This research involved applying a variety of different treatments including fasting and refeeding, diets differing in macronutrient composition, and/or central administration of neuropeptide Y, xenopsin, neuropeptide K, oxytocin, mesotocin, gonadotropin-inhibitory hormone, and prolactin-releasing peptide, after which I measured feeding behavior and various aspects of hypothalamic physiology. I measured nuclei activation in hypothalamic appetite-associated regions including the lateral hypothalamus, paraventricular nucleus, ventromedial hypothalamus, dorsomedial nucleus, and arcuate nucleus and I measured gene expression of various appetite-associated factors in the whole hypothalamus and individual nuclei. These data provided information about the regions of the brain involved in mediating effects on appetite and the molecular pathways involved in the effect on appetite. There were differences in dose threshold sensitivity to various injected factors in the different stocks, differential responses to fasting and refeeding, and differences in nuclei and genes that were activated in response to the various treatments. These data provide valuable insights on the molecular mechanisms that are associated with the short-term regulation of feeding behavior and pathways that may be genetically stock-dependent. / PHD

Mammalian and avian species differ in some appetite-related aspects including how and which neurotransmitters and hormones regulate appetite. The objective of this research was to determine how two satiety-inducing neuropeptides regulate feeding behavior in avian models. Neuropeptide FF (NPFF) was intracerebroventricularly (ICV) injected into Japanese quail and decreased food intake at a dose of 32 nmol. NPFF-injected quail had increased expression levels of hypothalamic melanocortin subtype 3 receptor and decreased expression levels of neuropeptide Y receptor subtype 1 mRNAs compared to vehicle-injected controls. In a second study, gastrin was ICV injected into broiler chicks and decreased food intake at a dose of 500 ng (0.12 nmol). There was increased c-Fos immunoreactivity in the lateral hypothalamus (LH), paraventricular nucleus (PVN), arcuate nucleus, nucleus of the solitary tract, and area postrema at 1 h post-injection. Although a variety of genes were measured in those activated nuclei, there were only differences in melanin-concentrating hormone mRNA in the LH and corticotropin-releasing factor (CRF) mRNA in the PVN, suggesting that CRF signaling was involved in the hypothalamic response to gastrin. However, co-injection of gastrin and astressin, a CRF receptor antagonist did not affect gastrin-induced suppression of food intake, implying that the CRF receptors may not be directly associated with gastrin-induced satiety. Identifying the molecular pathways that mediate the effects of anorexigenic neuropeptides in birds will lead to the development of novel treatment options for appetite-related diseases and increased understanding of factors that affect production efficiency in commercial poultry and survival/resource allocation in wild birds. / Master of Science

Adrenal corticosterone and aldosterone content, body weight changes and serum osmolality were examined during water restriction and water deprivation. Progressive water deprivation resulted in increased serum osmolality and decreased body weight; adrenal aldosterone content did not change. Adrenal corticosterone content tended to be elevated during early water deprivation indicating a stress response, but tended to decrease after seven days of water deprivation suggesting adrenal fatigue. During water restriction, after the period of weight loss, adrenal elevated corticosterone content and serum osmolality were elevated. As the birds began to gain weight aldosterone did not change, but adrenal corticosterone content and serum osmolality approached control values, suggesting the birds were beginning to adapt to the water restriction. The lack of an aldosterone response suggests that high sodium in the diet was more important than the water regimes in regulating aldosterone. The adrenal was sensitive to ACTH as indicated by the elevated adrenal aldosterone and corticosterone content after ACTH injection, however sodium status probably affects the aldosterone response to ACTH. / Master of Science

The relationships among body weight, body composition, adipose tissue cellularity and the onset of sexual maturity were studied in Japanese quail (Coturnix coturnix japonica). In an initial experiment, body composition and sexual maturity were examined in response to photoperiodic and hormonal manipulations. Attempts were made to modify body composition, and thereby age at sexual maturity, by feeding diets containing PTU (4-phenyl-2 thiouracil), by imposing a daily photoperiod (IP) of four hours, by the subcutaneous implantation of estrogen to females and testosterone to males, and by the intramuscular injection of turkey growth hormone and anti-sera to turkey growth hormone. The quail were sacrificed at 63 days of age and body composition was examined. Quail subjected to the IP treatment failed to enter sexual maturity by 63 days of age, while about 50% of the controls receiving a photoperiod of 14 hours were sexually mature at this age. The failure of these quail to mature was associated with a reduction in body fat. The effects of the other treatments on sexual maturity, however, were not consistently associated with differences in body weight and/or body composition. In the second phase of this study, adipocyte hyperplasia was examined in relation to sexual maturity. Total DNA concentrations in the stromal and lipocyte fractions of collagenase-digested abdominal fat depots were determined on a chronological age basis from 28 to 240 days of age. In both males and females, significant increases in abdominal fat weights at ages beyond the age at sexual maturity were associated with increased DNA concentrations in abdominal fat adipose tissue. These results suggested that mature Japanese quail were capable of hyperplastic fat deposition. In the final phase of this study, the incorporation of methyl-³H-thymidine into DNA of lipid and non-lipid fractions of collagenase-digested abdominal fat from both ad libitum and restricted-fed (70% of ad libitum intake) quail was examined. Regardless of the feeding regime and stage of maturity, substantial radioactivity was recovered from both the stromal and lipocyte fractions when the quail were examined 24 hours after the administration of tritiated thymidine. When quail were examined five days after the administration of tritiated thymidine, an apparent migration of radioactivity from stromal to lipocyte DNA occurred. It was concluded that this pattern represented mitotic activity of adipocyte progenitor cells located in non-lipid fractions of adipose tissue, and the subsequent maturation of these cells into lipocytes as they accumulated lipid. The hypothesis that adipocyte progenitors reside in both the stromal and lipocyte fraction, however, was not disproven. Nevertheless, the similarity of results obtained prior to, at, and subsequent to the onset of lay indicated that adipocyte hyperplasia contributes to increases in adipose tissue mass in mature Japanese quail. / Ph. D.

The neuroendocrinology of masculine sexual behavior was examined in Japanese quail selected bi-directionally for adult mating frequency. Experiments were conducted with brain tissues from functionally castrated, High (HM) and Low Mating (LM) line quail to compare (1) the in vivo aromatization of ³H-testosterone and (2) cytosolic estradiol-binding by in vitro saturation analyses. After in vivo incubation with ³H-testosterone, all radioactivity recovered in brain tissues was in the form of testosterone, dihydrotestosterone, or estradiol. Neither the total ³H nor ³H-testosterone metabolite radioactivity differed upon comparison of the two genetic lines. Of all ³H-testosterone metabolite radioactivity, ³H-estradiol represented 45 ± 6% in the HM line and 46 ± 6% in the LM line, indicating that the line difference in mating frequency was not due to a corresponding difference in aromatase activity. Inasmuch as both the HM and LM line birds actively converted testosterone to estradiol, these results implicated a neural mechanism involving estradiol-receptor interactions. Estradiol-receptor binding parameters were estimated in subsequent experiments by fitting a hyperbolic saturation curve to point measurements of total binding. Using this single-class binding site model, the apparent dissociation constant (K_d) for the estradiol-receptor interaction in the HM line was 0.40 ± .06 nM and the number of specific estradiol binding sites (B_max) was 10.4±.4 fmoles/mg cytosol protein. For the LM line, an apparent Kd of 0.41 ± .20 nM and a B<max> of 9.50 ± 1.0 fmoles/mg cytosol protein were obtained. The similarity between corresponding binding parameters for the divergent mating lines indicated that the number and/or estradiol-binding affinity of a single class of cytosol receptors was also not responsible for the line difference in mating frequency. Though these results confirm that interaction of estradiol with cytosol receptors was not the limiting neuroendocrinological mechanism in the differential expression of masculine sexual behavior in quail, the possible involvement of dynamic interrelationships between cytoplasmic and nuclear estrogen binding was discussed. / Ph. D.