Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Synthesis and Regulation of Thyroid Hormones01:20

Synthesis and Regulation of Thyroid Hormones

Low blood levels of the thyroid hormones — triiodothyronine (T3) and thyroxine (T4) — signal the hypothalamus to release the thyrotropin-releasing hormone (TRH). TRH then reaches the pituitary gland and stimulates the release of thyroid-stimulating hormone(TSH) into the bloodstream.
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The iodine is then...
Functions of Thyroid Hormones01:18

Functions of Thyroid Hormones

The thyroid hormone (TH) plays a pivotal role in the intricate orchestration of physiological processes, exerting profound effects on development, metabolism, and homeostasis throughout different life stages.
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
Hyperthyroidism I: Introduction01:25

Hyperthyroidism I: Introduction

Hyperthyroidism is a type of thyrotoxicosis characterized by the thyroid gland's overproduction of the thyroid hormones triiodothyronine (T3) and thyroxine (T4). This hormone excess increases the basal metabolic rate and enhances sensitivity to catecholamines.DiagnosisDiagnosis is based on clinical features and biochemical testing. It typically shows suppressed thyroid-stimulating hormone (TSH) levels below 0.4 mIU/L, with elevated free T3 and/or T4. Additional tests, including thyroid...
Hypothyroidism II: Pathophysiology01:23

Hypothyroidism II: Pathophysiology

Hypothyroidism is a disorder characterized by insufficient production of thyroid hormones, which regulate metabolism, energy balance, and multiple organ systems.TypesHypothyroidism is classified based on the level of dysfunction. Primary hypothyroidism results from intrinsic thyroid gland dysfunction, causing reduced hormone production despite normal or increased stimulation. Secondary hypothyroidism arises from inadequate thyroid-stimulating hormone (TSH) secretion by the pituitary. Tertiary...
Hyperthyroidism II: Pathophysiology01:27

Hyperthyroidism II: Pathophysiology

Hyperthyroidism is a hypermetabolic state caused by elevated levels of thyroid hormones, triiodothyronine (T3) and thyroxine (T4). It results from dysregulation at the thyroid, pituitary, or immune system level and affects multiple organ systems.PathophysiologyThe most common cause of hyperthyroidism is Graves’ disease, an autoimmune disorder in which antibodies, specifically thyroid-stimulating antibodies (TSAb), a subtype of TSH receptor antibodies (TRAb), bind to and activate TSH receptors...
The Thyroid Gland01:23

The Thyroid Gland

The thyroid gland is a small, butterfly-shaped gland located in the neck and covers the anterior surface of the trachea. The gland has two lateral lobes connected by a thin tissue mass called the isthmus. Internally, each lobe comprises many small spherical structures known as thyroid follicles, surrounded by a network of blood vessels.
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Chronic ethanol induces a pro-inflammatory switch in interleukin-1β regulation of GABAergic signaling in the medial prefrontal cortex of male mice.

Brain, behavior, and immunity·2023
Same author

PACAP regulation of central amygdala GABAergic synapses is altered by restraint stress.

Neuropharmacology·2019
Same author

Role of TLR4 in the Modulation of Central Amygdala GABA Transmission by CRF Following Restraint Stress.

Alcohol and alcoholism (Oxford, Oxfordshire)·2018
Same author

Hypothalamic vasopressin systems are more sensitive to the long term effects of social defeat in males versus females.

Psychoneuroendocrinology·2014
Same author

Initiation of egg production by turkey breeder hens: sexual maturation and age at lighting.

Poultry science·2010
Same author

Exposure duration to long day lengths associated with the expression of photorefractoriness in turkey breeder hens.

Poultry science·2008

Related Experiment Video

Updated: Jun 8, 2026

Separation of Avian Preovulatory Follicle Granulosa and Theca Cell Layers for Downstream Applications
05:04

Separation of Avian Preovulatory Follicle Granulosa and Theca Cell Layers for Downstream Applications

Published on: October 25, 2024

Initiating egg production in turkey breeder hens: thyroid hormone involvement.

T D Siopes1, J R Millam, M Q Steinman

  • 1Department of Poultry Science, North Carolina State University, Raleigh 27695, USA. tom_siopes@ncsu.edu

Poultry Science
|September 21, 2010
PubMed
Summary

Thyroid hormone suppression using 6-n-propyl-2-thiouracil (PTU) can advance turkey egg production by enhancing photosensitivity. This method proved superior to short-day exposure for conferring photosensitivity in juvenile turkeys.

More Related Videos

In vivo Characterization of Endocrine Disrupting Chemical Effects via Thyroid Hormone Action Indicator Mouse
04:14

In vivo Characterization of Endocrine Disrupting Chemical Effects via Thyroid Hormone Action Indicator Mouse

Published on: October 6, 2023

In Ovo Feeding of Commercial Broiler Eggs: An Accurate and Reproducible Method to Affect Muscle Development and Growth
06:38

In Ovo Feeding of Commercial Broiler Eggs: An Accurate and Reproducible Method to Affect Muscle Development and Growth

Published on: September 20, 2021

Related Experiment Videos

Last Updated: Jun 8, 2026

Separation of Avian Preovulatory Follicle Granulosa and Theca Cell Layers for Downstream Applications
05:04

Separation of Avian Preovulatory Follicle Granulosa and Theca Cell Layers for Downstream Applications

Published on: October 25, 2024

In vivo Characterization of Endocrine Disrupting Chemical Effects via Thyroid Hormone Action Indicator Mouse
04:14

In vivo Characterization of Endocrine Disrupting Chemical Effects via Thyroid Hormone Action Indicator Mouse

Published on: October 6, 2023

In Ovo Feeding of Commercial Broiler Eggs: An Accurate and Reproducible Method to Affect Muscle Development and Growth
06:38

In Ovo Feeding of Commercial Broiler Eggs: An Accurate and Reproducible Method to Affect Muscle Development and Growth

Published on: September 20, 2021

Area of Science:

  • Animal Science
  • Endocrinology
  • Poultry Science

Background:

  • Thyroid hormones play a crucial role in avian reproduction and development.
  • Understanding the interplay between thyroid hormones and photoperiodism is key to optimizing poultry production.

Purpose of the Study:

  • To investigate the role of thyroid hormones in turkey photosensitivity and photorefractoriness.
  • To determine if thyroid hormone suppression can substitute for short-day exposure in conferring photosensitivity.
  • To assess the impact of thyroid suppression on reproductive development and egg production in turkeys.

Main Methods:

  • Administered 6-n-propyl-2-thiouracil (PTU), an antithyroidal agent, to female turkeys at different developmental stages.
  • Utilized long day lengths (16L:8D) and short day lengths (8L:16D) to study photoperiodic responses.
  • Measured egg production rates, egg weight, and plasma levels of triiodothyronine and thyroxine via radioimmunoassay (RIA).
  • Assessed photoinduced neuronal activity using immunohistochemical analysis of fos-related antigen (FRA) expression in the hypothalamus.

Main Results:

  • PTU treatment, from 0-16 weeks or 10-18 weeks, significantly suppressed thyroid hormones and advanced egg production compared to controls.
  • PTU-treated turkeys exhibited a greater rate of lay, and egg weight normalized by 28 weeks.
  • Thyroid suppression did not impair photoinduced FRA expression, indicating effects downstream of initial photostimulation.
  • PTU treatment effectively forestalled egg production until withdrawal, after which it rose sharply.

Conclusions:

  • Pharmacological suppression of thyroid hormones can effectively confer photosensitivity on juvenile turkeys, outperforming short-day exposure.
  • Reproductive development does not limit egg production when turkeys are photostimulated around 20 weeks of age.
  • The influence of thyroid suppression on photostimulation occurs downstream of photoinduced neuronal activity (FRA expression).
  • These findings suggest potential for significantly advancing the age of photoinduced egg production in commercial turkey flocks.