CYCLIC VARIATIONS OF CORTISOL, TRIIODOTYRONINE (T3) AND TYROXINE (T4) ON BEFORE AND AFTER PARTURITION OF QUARTER HORSE MARES

Authors

  • Pedrinho Paes Teixeira UFG
  • Maria Lúcia Gambarini Meirinhos UFG
  • João Teodoro Pádua UFG
  • Dirson Vieira UFG

DOI:

https://doi.org/10.5216/cab.v9i2.539

Keywords:

Sanidade Animal, Pordução e Reprodução

Abstract

This study was designed to evaluate changes in plasma concentrations of cortisol (Cs), triiodothyronine (T3) and thyroxine (T4), as well as their circadian rhythm during peripartal period of Quarter Horse mares. Eighteen clinically healthy mares, with age between 60 and 96 months and alive weight (AW) between 350 and 420 Kg were divided in three groups (n=6) according the reproductive status, that means: no pregnant (TE), Pregnant (GE) and after parturition (PA).The blood samples were taken during 24 hours in intervals of two hours.There was no differences between cortisol levels regarding the reproductive status and periods of blood samples collections. This hormone showed a circadian rhythm, with accentuated oscillation in TE, but small for GE and PA. For T3 and T4 there was difference between reproductive status (P<0.05 and P<0.01), respectively, as well as for the periods (P<0.01 and P<0.05), respectively. It was possible to characterize the circadian rhythm for both hormones, verifying great oscillation for T3 in PA in the morning. It was possible to conclude that the final phase of pregnancy alter cortisol , T3 and T4 secretion standards, keeping, however, the rhythm, suggesting an organism adaptation along the peripartal period.

 

KEY WORDS: Equine, reproductive status, hormones, circadian rhythm.

Downloads

Download data is not yet available.

Author Biography

Pedrinho Paes Teixeira, UFG

Professor da Escola de Veterinária da UFG

Downloads

Published

2008-07-09

How to Cite

TEIXEIRA, P. P.; MEIRINHOS, M. L. G.; PÁDUA, J. T.; VIEIRA, D. CYCLIC VARIATIONS OF CORTISOL, TRIIODOTYRONINE (T3) AND TYROXINE (T4) ON BEFORE AND AFTER PARTURITION OF QUARTER HORSE MARES. Brazilian Animal Science/ Ciência Animal Brasileira, Goiânia, v. 9, n. 2, p. 263–271, 2008. DOI: 10.5216/cab.v9i2.539. Disponível em: https://revistas.ufg.br/vet/article/view/539. Acesso em: 24 nov. 2024.

Issue

Vol. 9 No. 2 (2008)

Section

Animal Production

License

Authors who publish with this journal agree to the following terms:

  1. Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
  2. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
  3. Authors are permitted and encouraged to post their work online (e.g. in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).