Life Sciences Commons^™

Lesioning Of The Nucleus Of The Hippocampal Commissure Followed By Food Deprivation Stress In Birds Demonstrates Simultaneous Involvement In Both The Hypothalamo-Pituitary-Adrenal Axis And The Hypothalamo-Pituitary-Thyroid Axis, Michael Thomas Kidd Jr.

Graduate Theses and Dissertations

The hypothalamo-pituitary-adrenal (HPA) axis is the regulatory system for the neuroendocrine stress response within vertebrates. Within the HPA axis corticotropin releasing hormone (CRH) is a major regulator and driving hormone. A structure named the nucleus of the hippocampal commissure (NHpC) has been found to contain CRH neurons and also these neurons respond to early food deprivation stress significantly prior to the paraventricular nucleus (PVN), the major driving nucleus of the classic neuroendocrine HPA axis. The objective of this study was to perform a knock down of the NHpC via electrolytic lesioning, thus eliminating a significant portion of its population of …

Study Of Three Potential Variables That May Impact The Maximum Shear Force And Shear Variation During The Growth And Transport Of Mixed Sex Broilers Grown In Commercial Poultry Houses, Mark Christie

Graduate Theses and Dissertations

Temperature conditions during the transportation to the processing facility of commercial broilers have a direct impact on the meat texture, specifically maximum shear force and shear variation of cooked breast meat. Analysis of a calendar year of flock data (N=346), reveals that the largest impact of transport conditions, specifically temperature, is on the standard deviation of the flocks range of cooked shear values. The optimal transport temperature that yields broiler breast meat with average flock minimum shear and standard deviation values is approximately 60°F. The shear values for flocks at or near 60°F are on average 1 kg less than …

Genomic Approaches To Identify Important Traits In Avian Species, Bhuwan Khatri

Graduate Theses and Dissertations

This dissertation focusses on identifying different molecular markers that have impact on overall poultry production. Chapter one reviews microRNA (miRNA), copy number variation (CNV) and single nucleotide polymorphism (SNP) as markers suggested in different avian species by various studies. It reviews modern genomic approaches that are employed for next generation sequencing data analysis and verification.

Chapter two seeks to identify and validate the muscle specific miRNAs in the breast muscle of modern broilers and its foundational chicken line. Small RNA sequencing was performed to identify differentially expressed mature miRNAs in the breast muscles of these two chicken lines. Results showed …

Noninvasive Measures Of Stress And Lameness In Broilers, Shawna L. Weimer

Graduate Theses and Dissertations

The concept of broiler chicken welfare has evolved from a component of animal husbandry to a label on a chicken product package. Recent attention from the public has led to the need for higher welfare standards for animal production. A primary concern of broiler production is low activity/locomotion attributed to fast growth rates leading to poor leg health. To collect the scientific data necessary to determine conditions providing the best welfare for the bird, multiple methods of assessment are required. Stress is influenced by external (temperature, humidity, lighting, stocking density) and internal (metabolism, thermoregulation, hormonal balance) factors. This series of …

Central Role Of Vasotocin In The Neuroendocrine Regulation Of Stress Responses And Food Intake In Chickens, Gallus Gallus, Gurueswar Nagarajan

Graduate Theses and Dissertations

It is well known that arginine vasotocin (AVT) in birds is involved in physiological homeostasis such as cardiovascular, osmotic regulation as well as reproductive functions. Pertinent to these physiological functions, AVT immunoreactive (-ir) neurons in the hypothalamus have been found associated with hemorrhage, dehydration, oviposition and other physiological regulation. Evidence, however, suggests that AVT also plays significant roles in modulating behavior, memory, stress, and food intake. This dissertation research addresses the latter two neuroendocrine functions of AVT in detail within the chicken brain. First, the functional role of AVT-ir neurons in conjunction with corticotropin releasing hormone (CRH)-ir neurons in the …

Identification Of Molecular Signatures Of Environmental And Nutritional Stress Responses In Poultry, Phuong Hieu Nguyen

Graduate Theses and Dissertations

Poultry production plays an important role in the food supply and security for billions of people. Poultry meat is considered the most efficient, nutritious source of protein, without religious taboos, and is relatively inexpensive. However, the poultry industry is facing substantial challenges. The global environmental temperature has experienced dramatic changes in the last few years. Modern broilers are not well adapted to environmental challenges (heat and cold stress), which have resulted in heavy economic loss in the poultry industry worldwide. In addition, the use of feed restriction regimens in management of breeders as well as the transportation of young chicks …

Central Administration Of Neuropeptide Y (Npy) And Vasotocin 4 Receptor (Vt4r/V1ar) Antagonists On Food Intake And A Stress Response In Chicks, Megan Ann Hancock

Graduate Theses and Dissertations

The objective of this study was to determine the central effect of the VT4R antagonists (SR-49059 and H-5350 (Manning compound)) on corticosterone (CORT) levels during stress and food intake. A 22-gauge stainless steel guide cannula was surgically implanted into the lateral ventricle of the birds. A preliminary study was done to test the antagonists and their role on food intake. Birds were injected with saline, NPY (4µg), NPY (4µg)+SR-49059 (250ng), or NPY (4µg)+Manning compound (250ng). Birds injected with saline had the lowest 1h food intake (17.7g1.6). Birds injected with NPY+saline had a significantly higher intake (27.1g 1.0), which was enhanced …

Characterization Of The Vasotocin Receptor Subtype 4 (Vt4r) In The Brain And Pituitary Gland Of The Chicken, Gallus Gallus, Rajamani Selvam

Graduate Theses and Dissertations

The present study investigated the distribution of the vasotocin subtype four receptor (VT4R) in brain and pituitary gland of the chicken, Gallus gallus. The anterior pituitary cell types associated with the VT4R were also determined. Two polyclonal antibodies were raised in rabbit against a cocktail of peptides, 15 amino acids from the amino terminal region and 17 amino acids from the carboxy terminal region of VT4R receptor. The antibody was validated utilizing the Western blot and immunocytochemistry. A single band at 47KDa utilizing membrane protein extracts of chicken brain and pituitary tissues was shown for the VT4R antibody. A peptide …