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.

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

Four experiments were conducted on hens of turkey and Japanese quail. In Experiment I, turkey hens were fed diets containing either 0% added fat, 3.5% animal-vegetable fat blend (AV) or 3.5% dry fat product (DF). In Experiment II with turkey hens, 2 holding diets and 4 breeder diets were investigated. The holding diets contained either 0% added fat or 5% of AV. The breeder diets contained 0% added fat of 5% of one of the following: AV, corn oil (CO) or olive oil (OO). In Experiment III with Japanese quail, 3 pre-breeder (PB) and 3 breeder diets (BD) were studied. They contained either 0, 3.5 or 7% added AV. In Experiment IV with Japanese quail, all diets contained 97% of a semi-purified basal diet and 3% of one of the following: corn starch (CS), corn oil (CO), palmitic acid (PA), oleic acid (OA), linoleic acid (LA) or linolenic acid (LN). The fatty acid composition of plasma and yolk lipids of both turkeys and quail was influenced by the fatty acid composition of the diets. Quail fed a CO diet deposited more linoleic acid in the egg than did those on a LA diet. (Abstract shortened by UMI.)

No description available.

Call number: LD2668 .T4 1979 O26 / Master of Science

No description available.

Thesis (Ph.D.)--McMaster University, 2005. / Advisor: Bennett Galef. Includes bibliographical references. Also available online.

Japanese quail hens were used to study the effect of feeding palmitic, oleic or linoleic acids on the reproductive performance, tissue fatty acid composition and embryo lipid metabolism. Quail fed palmitic acid consumed more feed than those fed either oleic or linoleic acids. The highest level of reproductive performance was observed in quail fed palmitic acid followed by those fed oleic and linoleic acids. The highest level of embryo survival, observed in the palmitic acid fed group, was associated with more rapid mobilization and assimilation of yolk material by the embryo during incubation and it was not related to changes in eggshell quality. High levels of oleic and linoleic acids were found in egg yolk, plasma and liver lipids from quail fed oleic and linoleic acids, respectively. However, feeding palmitic acid resulted in elevated levels of palmitoleic acids in all three tissues. The fatty acid profiles of phospholipid, triglyceride and cholesterol esters of embryonic tissues were consistently influenced by the fatty acid composition of the yolk lipids and the stage of development. Feeding palmitic acid promoted more retention of labeled fatty acids in embryo lipids. Labeled oleic acid was preferentially esterified in the cholesterol ester fraction of yolk sac membrane lipids, and it appears that this fatty acid is utilized to a great extent by the quail embryo during its development.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph.D.)--McMaster University, 2004. / Advisor: Bennett Galef. Includes bibliographical references (leaves 73-90). Also available online.