Related Experiment Video
Updated: Aug 19, 2026

Using a Thermal Camera to Measure Heat Loss Through Bird Feather Coats
Published on: June 17, 2020
Metabolic rate and thyroid activity of hens in relation to the state of feathering
Abstract:
Heat production, rectal temperature and thyroid activity were determined in NH X Lg hens that were 40 and 80% defeathered. Within individual groups there was a significant increase in heat production only in hens that were 80% defeathered. In comparison with the control group, defeathered chickens had higher metabolic rates during each examined period. During the third week of the experiment there was a temporary drop in the rectal temperature of the experimental birds. After nine weeks chicken with the greatest degree of defeathering had the highest thyroid weight and the highest levels of thyroxin in the blood plasma.
More Related Videos
Related Concept Videos
The Thyroid Gland
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...
Synthesis and Regulation of Thyroid Hormones
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 Hormones
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...
Metabolic Rate
The Basal Metabolic Rate (BMR) measures the energy expended at rest.
Several factors influence the...
Hyperthyroidism I: Introduction
Hyperthyroidism II: Pathophysiology

