Effects of altering rostral brain stem temperature on temperature regulation in the Adelie penguin,Pygoscelis adeliae

1976 ◽  
Vol 362 (1) ◽  
pp. 7-13 ◽  
Author(s):  
E. Simon ◽  
Ch. Simon-Oppermann ◽  
H. T. Hammel ◽  
R. Kaul ◽  
J. Maggert
Keyword(s):  
Brain Stem ◽  
Temperature Regulation ◽  
Adélie Penguin ◽  
Pygoscelis Adeliae ◽  
Adelie Penguin ◽  
Stem Temperature

scholarly journals Growing in Antarctica, a challenge for white adipose tissue development in Adélie penguin chicks (Pygoscelis adeliae)

2008 ◽  
Vol 295 (5) ◽  
pp. R1671-R1679 ◽  
Author(s):  
Mireille Raccurt ◽  
Fannie Baudimont ◽  
Julien Tirard ◽  
Benjamin Rey ◽  
Elodie Moureaux ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Adipose Tissue ◽  
Fatty Acid Synthase ◽  
Growth Hormone Receptor ◽  
Adélie Penguin ◽  
Lipid Uptake ◽  
Tissue Development ◽  
Pygoscelis Adeliae ◽  
Adelie Penguin ◽  
Adipose Tissue Development

Rapid growth is of crucial importance for Adélie penguin chicks reared during the short Antarctic summer. It partly depends on the rapid ontogenesis of fat stores that are virtually null at hatching but then develop considerably (×40) within a month to constitute both an isolative layer against cold and an energy store to fuel thermogenic and growth processes. The present study was aimed at identifying by RT-PCR the major transcriptional events that chronologically underlie the morphological transformation of adipocyte precursors into mature adipocytes from hatching to 30 days of age. The peak expression of GATA binding protein 3, a marker of preadipocytes, at day 7 posthatch indicates a key proliferation step, possibly in relation to the expression of C/EBPα (C/EBPα). High plasma total 3,5,3′-triiodo-l-thyronine (T3) levels and high levels of growth hormone receptor transcripts at hatching suggested that growth hormone and T3 play early activating roles to favor proliferation of preadipocyte precursors. Differentiation and growth of preadipocytes may occur around day 15 in connection with increased abundance of transcripts encoding IGF-1, proliferator-activated receptor-γ, and C/EBPβ, gradually leading to functional maturation of metabolic features of adipocytes including lipid uptake and storage (lipoprotein lipase, fatty-acid synthase) and late endocrine functions (adiponectin) by day 30. Present results show a close correlation between adipose tissue development and chick biology and a difference in the scheduled expression of regulatory factors controlling adipogenesis compared with in vitro studies using cell lines emphasizing the importance of in vivo approaches.

A 9000-year record of Adélie penguin occupation and diet in the Windmill Islands, East Antarctica

2005 ◽  
Vol 17 (1) ◽  
pp. 57-66 ◽  
Author(s):  
STEVEN D. EMSLIE ◽  
ERIC J. WOEHLER
Keyword(s):  
Population Cycles ◽  
East Antarctica ◽  
Adélie Penguin ◽  
Pygoscelis Adeliae ◽  
Pleuragramma Antarcticum ◽  
Fish Prey ◽  
Adelie Penguin ◽  
Radiocarbon Dates ◽  
Nest Site Fidelity ◽  
Windmill Islands

We investigated 17 abandoned Adélie penguin (Pygoscelis adeliae) colonies in the Windmill Islands, East Antarctica, in summer 2002/03. Forty radiocarbon dates on penguin bones and eggshells from 13 of these sites indicate a near continuous occupation by breeding penguins in this region for over 9000 years. These dates refine the recent geological record in this region and indicate that deglaciation of the northern islands occurred much earlier than previously suggested. Dietary remains from these sites include at least 23 taxa of cephalopods and teleost fish. Quantification of these remains indicates significant fluctuations in the relative abundance of two of the more common major prey taxa. The Antarctic silverfish (Pleuragramma antarcticum Boulenger) was the most common teleost prey during all time periods represented by the ages of the sites, but preservational factors may explain a gradual decrease in the remains of this species in increasingly older sites. The most common cephalopod in the sediments was the squid, Psychroteuthis glacialis Thiele, which occurred in low numbers in most sites except one (Site 75). An unusually high number of squid beaks preserved in Site 75, dating to approximately 5700–6100 cal. yr BP, does not correlate with a decrease in fish prey at that time. The high number of abandoned penguin colonies (> 200) in the Windmill Islands may be due to population cycles in the past in association with low nest-site fidelity and movement by breeding penguins to new sites within this region.

Ontogeny of muscle bioenergetics in Adélie penguin chicks (Pygoscelis adeliae)

2013 ◽  
Vol 305 (9) ◽  
pp. R1065-R1075 ◽  
Author(s):  
Anaïs Fongy ◽  
Caroline Romestaing ◽  
Coralie Blanc ◽  
Nicolas Lacoste-Garanger ◽  
Jean-Louis Rouanet ◽  
...  
Keyword(s):  
Muscle Fiber ◽  
Relative Abundance ◽  
Oxidative Activity ◽  
Adélie Penguin ◽  
Pygoscelis Adeliae ◽  
Western Blots ◽  
Adelie Penguin ◽  
Isolated Mitochondria ◽  
Mitochondrial Fractions ◽  
Permeabilized Fibers

The ontogeny of pectoralis muscle bioenergetics was studied in growing Adélie penguin chicks during the first month after hatching and compared with adults using permeabilized fibers and isolated mitochondria. With pyruvate-malate-succinate or palmitoyl-carnitine as substrates, permeabilized fiber respiration markedly increased during chick growth (3-fold) and further rose in adults (1.4-fold). Several markers of muscle fiber oxidative activity (cytochrome oxidase, citrate synthase, hydroxyl-acyl-CoA dehydrogenase) increased 6- to 19-fold with age together with large rises in intermyofibrillar (IMF) and subsarcolemmal (SS) mitochondrial content (3- to 5-fold) and oxidative activities (1.5- to 2.4-fold). The proportion of IMF relative to SS mitochondria increased with chick age but markedly dropped in adults. Differences in oxidative activity between mitochondrial fractions were reduced in adults compared with hatched chicks. Extrapolation of mitochondrial to muscle respirations revealed similar figures with isolated mitochondria and permeabilized fibers with carbohydrate-derived but not with lipid-derived substrates, suggesting diffusion limitations of lipid substrates with permeabilized fibers. Two immunoreactive fusion proteins, mitofusin 2 (Mfn2) and optic atrophy 1 (OPA1), were detected by Western blots on mitochondrial extracts and their relative abundance increased with age. Muscle fiber respiration was positively related with Mfn2 and OPA1 relative abundance. Present data showed by two complementary techniques large ontogenic increases in muscle oxidative activity that may enable birds to face thermal emancipation and growth in childhood and marine life in adulthood. The concomitant rise in mitochondrial fusion protein abundance suggests a role of mitochondrial networks in the skeletal muscle processes of bioenergetics that enable penguins to overcome harsh environmental constraints.

scholarly journals Penguin megrivirus, a novel picornavirus from an Adélie penguin (Pygoscelis adeliae)

2019 ◽  
Vol 164 (11) ◽  
pp. 2887-2890 ◽  
Author(s):  
C. K. Yinda ◽  
J. Esefeld ◽  
H. U. Peter ◽  
J. Matthijnssens ◽  
R. Zell
Keyword(s):  
Adélie Penguin ◽  
Pygoscelis Adeliae ◽  
Adelie Penguin

Lack of daily heart rate rhythms in Adélie penguin chicks during the polar day

Polar Record ◽  
2019 ◽  
Vol 55 (6) ◽  
pp. 411-416
Author(s):  
Canwei Xia ◽  
Yanyun Zhang
Keyword(s):  
Heart Rate ◽  
Fourier Transformation ◽  
Daily Rhythm ◽  
Fast Fourier Transformation ◽  
Adélie Penguin ◽  
Pygoscelis Adeliae ◽  
Adelie Penguin ◽  
Heart Rates ◽  
Small Effect Size ◽  
Polar Day

AbstractDaily rhythms enable organisms to adapt to daily fluctuations in environmental factors. Do organisms still exhibit 24-h rhythms when living in habitats without obvious daily cycles in external signals? To answer this question, we measured the heart rates of six Adélie penguin (Pygoscelis adeliae) chicks on Inexpressible Island during the polar day between 15 and 21 January 2019. Averaged heart rates were between 186 and 233 beats/min for individual chicks. Both fast Fourier transformation and autocorrelation were employed to assess the daily rhythmicity. Based on fast Fourier transformation, a significant contribution of daily rhythm in heart rate variation was found only in one individual. Small effect size of significant autocorrelation coefficients was found in two individuals, while there was no significant autocorrelation coefficient for 24-h time lag in four other individuals. In summary, no prevailing daily rhythm of heart rate was found in these Adélie penguin chicks. We propose that the lack of daily rhythm in Adélie penguin chicks could be an adaptation to the local environment in the polar regions, but that the adaptive value thereof remains to be investigated.

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