THE EFFECTS OF HIBERNATION AND CAPTIVITY ON GLUCOSE METABOLISM AND THYROID HORMONES IN AMERICAN BLACK BEAR (URSUS AMERICANUS)

@inproceedings{McCain2013THEEO,
  title={THE EFFECTS OF HIBERNATION AND CAPTIVITY ON GLUCOSE METABOLISM AND THYROID HORMONES IN AMERICAN BLACK BEAR (URSUS AMERICANUS)},
  author={Stephanie L McCain and Edward C. Ramsay and Claudia Ann Kirk},
  booktitle={Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians},
  year={2013}
}
Abstract:  American black bears (Ursus americanus) have been shown to become transiently insulin resistant and hypothyroid during winter, but no studies have investigated these changes in long-term captive bears or in bears which remain awake year-round. Wild, captive hibernating, and captive nonhibernating bears were evaluated at times corresponding to three of their major physiologic stages: fall (hyperphagic stage), winter (hibernation stage), and summer (normal activity stage). Combined… 
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TLDR
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Can offsetting the energetic cost of hibernation restore an active season phenotype in grizzly bears (Ursus arctos horribilis)?
TLDR
The partial depression of circulating FFA with feeding likely explains the incomplete restoration of insulin sensitivity and other metabolic parameters in hibernating bears and provides a highly controlled model to examine the relationship between nutrient availability and metabolism on the hibernation phenotype in bears.
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Hibernating bears remained euglycemic, possibly due to hyperinsulinemia and hyperglucagonemia, and adipokine concentrations were relatively low throughout the active season but peaked in mid-October prior to hibernation when fat content was greatest.
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The results strongly suggest that the shift in lipid composition is well conserved among hibernators, independent of body mass and of the animals’ body temperature.
Seasonal body mass changes and feed intake in spectacled bears (Tremarctos ornatus) at Zurich Zoological Garden
TLDR
The data indicate that body mass fluctuation in a range considered ideal for the species was mostly based on the additional food whose amount was adjusted by the animal keepers on a daily basis, a good example of the skill required in animal husbandry.
Hibernation induces widespread transcriptional remodeling in metabolic tissues of the grizzly bear
TLDR
It is found that during hibernation, adipose tissue has the largest number of differentially expressed genes of the three tissues examined, revealing potential therapeutic targets for human diseases.
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TLDR
Food sources for North America’s grizzly bear population have changed as habitats have fragmented, altering available resources and putting bears in contact with unnatural foods, and Bears have evolved mechanisms to tolerate obesity, and do not develop adverse health consequences despite storing massive amounts of body fat.
EVALUATION OF THYROID HORMONES AND AS INFLUENCED BY TREATMENT WITH DESLORELIN IN PALLAS' CATS (OTOCOLOBUS (FELIS) MANUL)
  • Kristina M. Delaski, K. Gamble
  • Medicine, Biology
    Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians
  • 2015
TLDR
The values reported for the untreated captive and free-ranging group, while representing a small sample size, can serve as a baseline assessment when evaluating the thyroid status of captive Pallas' cats.
Changes in liver microRNA expression and their possible regulatory role in energy metabolism-related genes in hibernating black bears.
TLDR
The results suggest that the increased levels of hepatic miRNA during hibernation negatively regulate the expression of targeted genes predicted to be involved in the transport of energy source and de novo fatty acid synthesis, is consistent with a regulatory role of these miRNAs in energy metabolism in hibernating black bears.
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