Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris)

We measured metabolic hormones and several key metabolites in breeding adult male northern elephant seals to examine the regulation of fuel metabolism during extended natural fasts of over 3 months associated with high levels of energy expenditure. Males were sampled twice, early and late in the fas...

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Main Authors: Crocker, Daniel E., Ortiz, Rudy M., Houser, Dorian S., Webb, Paul M., Costa, Daniel P.
Format: Text
Language:unknown
Published: DOCS@RWU 2012
Subjects:
DDE
Dee
Online Access:https://docs.rwu.edu/fcas_fp/84
https://docs.rwu.edu/cgi/viewcontent.cgi?article=1083&context=fcas_fp
id ftrwuniv:oai:docs.rwu.edu:fcas_fp-1083
record_format openpolar
spelling ftrwuniv:oai:docs.rwu.edu:fcas_fp-1083 2023-05-15T16:05:21+02:00 Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris) Crocker, Daniel E. Ortiz, Rudy M. Houser, Dorian S. Webb, Paul M. Costa, Daniel P. 2012-01-01T08:00:00Z application/pdf https://docs.rwu.edu/fcas_fp/84 https://docs.rwu.edu/cgi/viewcontent.cgi?article=1083&context=fcas_fp unknown DOCS@RWU https://docs.rwu.edu/fcas_fp/84 https://docs.rwu.edu/cgi/viewcontent.cgi?article=1083&context=fcas_fp Arts & Sciences Faculty Publications Elephant seal Thyroxine Deiondination DDE Fasting Leptin Ghrelin Cortisol Adipose tissue Biology text 2012 ftrwuniv 2022-04-10T20:37:01Z We measured metabolic hormones and several key metabolites in breeding adult male northern elephant seals to examine the regulation of fuel metabolism during extended natural fasts of over 3 months associated with high levels of energy expenditure. Males were sampled twice, early and late in the fast, losing an average of 23% of body mass and 47% of adipose stores between measurements. Males exhibited metabolic homeostasis over the breeding fast with no changes in glucose, non-esterified fatty acids, or blood urea nitrogen. Ketoacids increased over the fast but were very low when compared to other fasting species. Changes within individuals in total triiodothyronine (tT3) were positively related to daily energy expenditure (DEE) and protein catabolism. Differences in levels of thyroid hormones relative to that observed in weaned pups and females suggest a greater deiodination of T4 to support the high DEE of breeding males. Relative levels of leptin and ghrelin were consistent with the suppression of appetite but a significant reduction in growth hormone across the fast was contrary to expectation in fasting mammals. The lack of the increase in cortisol during fasting found in conspecific weaned pups and lactating females may contribute to the ability of breeding males to spare protein despite high levels of energy expenditure. Together these findings reveal significant differences with conspecifics under varying nutrient demands, suggesting metabolic adaptation to extended high energy fasts. Text Elephant Seal Elephant Seals Roger Williams University: DOCS@RWU Dee ENVELOPE(-59.767,-59.767,-62.433,-62.433)
institution Open Polar
collection Roger Williams University: DOCS@RWU
op_collection_id ftrwuniv
language unknown
topic Elephant seal
Thyroxine
Deiondination
DDE
Fasting
Leptin
Ghrelin
Cortisol
Adipose tissue
Biology
spellingShingle Elephant seal
Thyroxine
Deiondination
DDE
Fasting
Leptin
Ghrelin
Cortisol
Adipose tissue
Biology
Crocker, Daniel E.
Ortiz, Rudy M.
Houser, Dorian S.
Webb, Paul M.
Costa, Daniel P.
Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris)
topic_facet Elephant seal
Thyroxine
Deiondination
DDE
Fasting
Leptin
Ghrelin
Cortisol
Adipose tissue
Biology
description We measured metabolic hormones and several key metabolites in breeding adult male northern elephant seals to examine the regulation of fuel metabolism during extended natural fasts of over 3 months associated with high levels of energy expenditure. Males were sampled twice, early and late in the fast, losing an average of 23% of body mass and 47% of adipose stores between measurements. Males exhibited metabolic homeostasis over the breeding fast with no changes in glucose, non-esterified fatty acids, or blood urea nitrogen. Ketoacids increased over the fast but were very low when compared to other fasting species. Changes within individuals in total triiodothyronine (tT3) were positively related to daily energy expenditure (DEE) and protein catabolism. Differences in levels of thyroid hormones relative to that observed in weaned pups and females suggest a greater deiodination of T4 to support the high DEE of breeding males. Relative levels of leptin and ghrelin were consistent with the suppression of appetite but a significant reduction in growth hormone across the fast was contrary to expectation in fasting mammals. The lack of the increase in cortisol during fasting found in conspecific weaned pups and lactating females may contribute to the ability of breeding males to spare protein despite high levels of energy expenditure. Together these findings reveal significant differences with conspecifics under varying nutrient demands, suggesting metabolic adaptation to extended high energy fasts.
format Text
author Crocker, Daniel E.
Ortiz, Rudy M.
Houser, Dorian S.
Webb, Paul M.
Costa, Daniel P.
author_facet Crocker, Daniel E.
Ortiz, Rudy M.
Houser, Dorian S.
Webb, Paul M.
Costa, Daniel P.
author_sort Crocker, Daniel E.
title Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris)
title_short Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris)
title_full Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris)
title_fullStr Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris)
title_full_unstemmed Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris)
title_sort hormone and metabolite changes associated with extended breeding fasts in male northern elephant seals (mirounga angustirostris)
publisher DOCS@RWU
publishDate 2012
url https://docs.rwu.edu/fcas_fp/84
https://docs.rwu.edu/cgi/viewcontent.cgi?article=1083&context=fcas_fp
long_lat ENVELOPE(-59.767,-59.767,-62.433,-62.433)
geographic Dee
geographic_facet Dee
genre Elephant Seal
Elephant Seals
genre_facet Elephant Seal
Elephant Seals
op_source Arts & Sciences Faculty Publications
op_relation https://docs.rwu.edu/fcas_fp/84
https://docs.rwu.edu/cgi/viewcontent.cgi?article=1083&context=fcas_fp
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