Thyroid function testing in elephant seals in health and disease

Pamela K. Yochem, Frances M D Gulland, Brent S. Stewart, Martin Haulena, Jonna A Mazet, Walter M Boyce

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Northern Elephant Seal Skin Disease (NESSD) is a severe, ulcerative, skin condition of unknown cause affecting primarily yearling northern elephant seals (Mirounga angustirostris); it has been associated with decreased levels of circulating thyroxine (T4) and triiodothyronine (T3). Abnormalities of the thyroid gland that result in decreased hormone levels (hypothyroidism) can result in hair loss, scaling and secondary skin infections. However, concurrent illness (including skin ailments) can suppress basal levels of thyroid hormones and mimic hypothyroidism; when this occurs in animals with normal thyroid glands it is called "sick euthyroid syndrome". The two conditions (true hypothyroidism vs. "sick euthyroid") can be distinguished in dogs by testing the response of the thyroid gland to exogenous thyrotropin (Thyroid Stimulating Hormone, TSH). To determine whether hypothyroidism is involved in the etiology of NESSD, we tested thyroid function of stranded yearling elephant seals in the following categories: healthy seals (rehabilitated and ready for release; N = 9), seals suffering from NESSD (N = 16) and seals with other illnesses (e.g., lungworm pneumonia; N = 10). Levels of T4 increased significantly for all three categories of elephant seals following TSH stimulation, suggesting that seals with NESSD are "sick euthyroid" and that the disease is not associated with abnormal thyroid gland function.

Original languageEnglish (US)
Pages (from-to)635-640
Number of pages6
JournalGeneral and Comparative Endocrinology
Volume155
Issue number3
DOIs
StatePublished - Feb 1 2008

Fingerprint

Earless Seals
Mirounga
Mirounga angustirostris
thyroid function
Thyroid Gland
hypothyroidism
thyroid gland
skin diseases
seals
thyrotropin
Health
Hypothyroidism
Skin Diseases
skin (animal)
Thyrotropin
L-thyroxine
testing
triiodothyronine
yearlings
Skin

Keywords

  • Elephant seal
  • Hypothyroidism
  • Sick euthyroid
  • Thyroid hormones
  • Thyrotropin
  • Thyroxine
  • Triiodothyronine
  • TSH-stimulation test

ASJC Scopus subject areas

  • Endocrinology

Cite this

Thyroid function testing in elephant seals in health and disease. / Yochem, Pamela K.; Gulland, Frances M D; Stewart, Brent S.; Haulena, Martin; Mazet, Jonna A; Boyce, Walter M.

In: General and Comparative Endocrinology, Vol. 155, No. 3, 01.02.2008, p. 635-640.

Research output: Contribution to journalArticle

Yochem, Pamela K. ; Gulland, Frances M D ; Stewart, Brent S. ; Haulena, Martin ; Mazet, Jonna A ; Boyce, Walter M. / Thyroid function testing in elephant seals in health and disease. In: General and Comparative Endocrinology. 2008 ; Vol. 155, No. 3. pp. 635-640.
@article{052d6b22f1cd4327941dceed54b29974,
title = "Thyroid function testing in elephant seals in health and disease",
abstract = "Northern Elephant Seal Skin Disease (NESSD) is a severe, ulcerative, skin condition of unknown cause affecting primarily yearling northern elephant seals (Mirounga angustirostris); it has been associated with decreased levels of circulating thyroxine (T4) and triiodothyronine (T3). Abnormalities of the thyroid gland that result in decreased hormone levels (hypothyroidism) can result in hair loss, scaling and secondary skin infections. However, concurrent illness (including skin ailments) can suppress basal levels of thyroid hormones and mimic hypothyroidism; when this occurs in animals with normal thyroid glands it is called {"}sick euthyroid syndrome{"}. The two conditions (true hypothyroidism vs. {"}sick euthyroid{"}) can be distinguished in dogs by testing the response of the thyroid gland to exogenous thyrotropin (Thyroid Stimulating Hormone, TSH). To determine whether hypothyroidism is involved in the etiology of NESSD, we tested thyroid function of stranded yearling elephant seals in the following categories: healthy seals (rehabilitated and ready for release; N = 9), seals suffering from NESSD (N = 16) and seals with other illnesses (e.g., lungworm pneumonia; N = 10). Levels of T4 increased significantly for all three categories of elephant seals following TSH stimulation, suggesting that seals with NESSD are {"}sick euthyroid{"} and that the disease is not associated with abnormal thyroid gland function.",
keywords = "Elephant seal, Hypothyroidism, Sick euthyroid, Thyroid hormones, Thyrotropin, Thyroxine, Triiodothyronine, TSH-stimulation test",
author = "Yochem, {Pamela K.} and Gulland, {Frances M D} and Stewart, {Brent S.} and Martin Haulena and Mazet, {Jonna A} and Boyce, {Walter M}",
year = "2008",
month = "2",
day = "1",
doi = "10.1016/j.ygcen.2007.11.012",
language = "English (US)",
volume = "155",
pages = "635--640",
journal = "General and Comparative Endocrinology",
issn = "0016-6480",
publisher = "Academic Press Inc.",
number = "3",

}

TY - JOUR

T1 - Thyroid function testing in elephant seals in health and disease

AU - Yochem, Pamela K.

AU - Gulland, Frances M D

AU - Stewart, Brent S.

AU - Haulena, Martin

AU - Mazet, Jonna A

AU - Boyce, Walter M

PY - 2008/2/1

Y1 - 2008/2/1

N2 - Northern Elephant Seal Skin Disease (NESSD) is a severe, ulcerative, skin condition of unknown cause affecting primarily yearling northern elephant seals (Mirounga angustirostris); it has been associated with decreased levels of circulating thyroxine (T4) and triiodothyronine (T3). Abnormalities of the thyroid gland that result in decreased hormone levels (hypothyroidism) can result in hair loss, scaling and secondary skin infections. However, concurrent illness (including skin ailments) can suppress basal levels of thyroid hormones and mimic hypothyroidism; when this occurs in animals with normal thyroid glands it is called "sick euthyroid syndrome". The two conditions (true hypothyroidism vs. "sick euthyroid") can be distinguished in dogs by testing the response of the thyroid gland to exogenous thyrotropin (Thyroid Stimulating Hormone, TSH). To determine whether hypothyroidism is involved in the etiology of NESSD, we tested thyroid function of stranded yearling elephant seals in the following categories: healthy seals (rehabilitated and ready for release; N = 9), seals suffering from NESSD (N = 16) and seals with other illnesses (e.g., lungworm pneumonia; N = 10). Levels of T4 increased significantly for all three categories of elephant seals following TSH stimulation, suggesting that seals with NESSD are "sick euthyroid" and that the disease is not associated with abnormal thyroid gland function.

AB - Northern Elephant Seal Skin Disease (NESSD) is a severe, ulcerative, skin condition of unknown cause affecting primarily yearling northern elephant seals (Mirounga angustirostris); it has been associated with decreased levels of circulating thyroxine (T4) and triiodothyronine (T3). Abnormalities of the thyroid gland that result in decreased hormone levels (hypothyroidism) can result in hair loss, scaling and secondary skin infections. However, concurrent illness (including skin ailments) can suppress basal levels of thyroid hormones and mimic hypothyroidism; when this occurs in animals with normal thyroid glands it is called "sick euthyroid syndrome". The two conditions (true hypothyroidism vs. "sick euthyroid") can be distinguished in dogs by testing the response of the thyroid gland to exogenous thyrotropin (Thyroid Stimulating Hormone, TSH). To determine whether hypothyroidism is involved in the etiology of NESSD, we tested thyroid function of stranded yearling elephant seals in the following categories: healthy seals (rehabilitated and ready for release; N = 9), seals suffering from NESSD (N = 16) and seals with other illnesses (e.g., lungworm pneumonia; N = 10). Levels of T4 increased significantly for all three categories of elephant seals following TSH stimulation, suggesting that seals with NESSD are "sick euthyroid" and that the disease is not associated with abnormal thyroid gland function.

KW - Elephant seal

KW - Hypothyroidism

KW - Sick euthyroid

KW - Thyroid hormones

KW - Thyrotropin

KW - Thyroxine

KW - Triiodothyronine

KW - TSH-stimulation test

UR - http://www.scopus.com/inward/record.url?scp=38949211009&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=38949211009&partnerID=8YFLogxK

U2 - 10.1016/j.ygcen.2007.11.012

DO - 10.1016/j.ygcen.2007.11.012

M3 - Article

C2 - 18190914

AN - SCOPUS:38949211009

VL - 155

SP - 635

EP - 640

JO - General and Comparative Endocrinology

JF - General and Comparative Endocrinology

SN - 0016-6480

IS - 3

ER -