Development of the thyroid gland of New-Zealand white rabbit
Journal Title: Journal of Veterinary Medical Research - Year 2005, Vol 15, Issue 2
Abstract
The development of thyroid glands of New-Zeland rabbits was studied in 28 fetuses (10-30 days) and 28 rabbits (3 days-5 years). The thyroid premordia appeared at the 12th day of gestation as 2 masses of cords and clumps of cells. The gland assumed the bilobed form with a narrow isthmus in between at the 18th day. Small primitive follicles with narrow empty lumina appeared in 14-day-old fetuses. True follicles were recorded in 20-22 days old fetuses while colloid was seen in the lumina of the central follicles at the 24th day. Light (C- or Parafollicular) cells were seen for the first time at the 12th day. With development of the follicles, C-cells appeared between the follicular cells and some of them come in contact with colloid. The ultimobranchial body (UBB) was observed in 20 days old fetuses close to the thyroid anlage and entered into its tissue at the 22nd day. Later on, it gave thyroid-like follicles or ultimobranchial cysts. With the electron microscope (EM) follicular cells of earlydeveloping fetuses were not yet differentiated. They contained few ill-developed rough endoplasmic reticulum (rER) and mitochondria. The organelles became well developed and the cells started to secrete colloid in full term fetuses. The maximum rate of secretory activity was achieved in the glands of adult rabbits. Changes in the thyroid glands during the postnatal life up to 5 years of age (age of senility) were followed up and described.
Authors and Affiliations
S. M. Soliman1; Tagreed M. Nabil1; A. Z. El-Kerdawy1; A. M. El-Bayomy2 1Department of Cytology and Histology, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef, Egypt 2Department of pharmacology, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef, Egypt
Keywords
Related Articles
- EP ID EP682714
- DOI -
- Views 225
- Downloads 0
Some virulence factors of Escherichia coli isolated from diarrheic calves
Escherichia coliare the most common cause of diarrhea in calves. Diarrhea in calvesremains one of the most important problems faced by livestock, causing great economic losses. Some strains ofE. coli characterized by the...
Anti-inflammatory, antipyretic and analgesic effect of Achillea millefolium and Salix plants
he Anti-inflammatory, antipyretic and analgesic effect of Achillea millefolium and Salix were investigated in rats and mice. The extracts of Achillea millefolium exerted significant antiinflammatory, antipyretic and anal...
Color Doppler ultrasound as an accurate and rapid tool for early pregnancy diagnosis in buffaloes
The objective was to determine the accuracy of color Doppler ultrasound for diagnosis of early pregnancy in buffaloes based on the evaluation of corpus luteum blood flow (CLBF) on days 20 and 21 after mating. Local Egypt...
Study on the capability of a dual capripox vaccine in protection of cattle against LSD infection
The experiment applied on four groups of calves, each of four calves. Three calves from each group were vaccinated with one of the following attenuated vaccines: Lumpy skin disease vaccine (LSD), Romanian sheep pox (RSP)...
Beneficial roles of boron supplementation in the ration of rams on productive activity and semen quality
The aim of this study is to determine the effects of boron supplementation in ration of rams on their productive activity and semen quality. For that purpose, twelve rams were divided into two groups (6 rams/ each). Rams...