Ecology and Physiology of Fasting in King Penguin Chicks

The Auk ◽  
1987 ◽  
Vol 104 (2) ◽  
pp. 254-262 ◽  
Author(s):  
Yves Cherel ◽  
Jean-Claude Stahl ◽  
Yvon Le Maho
Keyword(s):  
Body Mass ◽  
Progressive Increase ◽  
Blood Analysis ◽  
King Penguin ◽  
Protein Breakdown ◽  
Adaptive Value ◽  
Field Investigations ◽  
Short Period ◽  
Initial Decrease ◽  
Free Ranging

Abstract Captive King Penguin (Aptenodytes patagonica) chicks can fast for 5 months during the subantarctic winter with a 70% decrease in body mass. To investigate the adaptive value of this remarkable resistance to starvation, we compared captive chicks with free-ranging chicks in their colony at Possession Island, Crozet Archipelago. The chicks in the colony, from mid-April to beginning of September (i.e. all winter) were fed only every 39 days by their parents; some were not fed at all. In spring (October-December) the surviving chicks were fed every 6 days, and their growth was completed. Overall chick mortality in the colony during the winter and subsequent spring was about 50%. Mortality was highest in October, 6 months after the beginning of the winter, and may be attributed mainly to starvation. The decrease in body mass in the free-ranging chicks was remarkably similar to that for captive birds. In both groups, three periods were characterized according to the observed changes in the daily decrease in body mass per unit body mass (dm/mdt): dm/mdt dropped during the first period (I) of 5-6 days, was minimum and steady during period II, which lasted about 4 months, and increased in period III. Blood analysis of the captive chicks indicated the three periods correspond to modifications in protein breakdown. An initial decrease in uricacidemia indicates period I is a short period of transition, marked by a decrease in protein breakdown. In period II a minimum and constant uricacidemia, in parallel with a progressive increase in ketonemia, indicates efficient protein sparing while most of the energy is derived from lipids. Period III is critical because, from a rise in uricacidemia concomitant with a decreasing ketonemia, proteins are no longer spared. The extreme resistance of King Penguin chicks to starvation in winter may be explained partly by the ability to spare proteins for several months (period II). It occurs at a growth stage when the parents' feeding visits are rare. Other laboratory and field investigations of birds suggest that the means by which a wide variety of domestic and wild species adapt to fasting also may be interpreted in terms of three periods corresponding to changes in protein breakdown.

Five months of fasting in king penguin chicks: body mass loss and fuel metabolism

1985 ◽  
Vol 249 (4) ◽  
pp. R387-R392 ◽  
Author(s):  
Y. Cherel ◽  
Y. Le Maho
Keyword(s):  
Uric Acid ◽  
Body Mass ◽  
Plasma Concentrations ◽  
Progressive Increase ◽  
King Penguin ◽  
Body Mass Loss ◽  
Protein Utilization ◽  
Fuel Metabolism ◽  
Protein Sparing ◽  
Beta Hydroxybutyrate

When king penguin chicks are 3–4 mo old, they enter a season of interrupted growth due to long periods of fasting, because they are irregularly fed in winter. Nine captive chicks [mean initial body mass (m) = 12.5 kg] had fasted an average of 5 mo at the end of the experiment; m was then 4.0 kg, a 68% decrease. They probably could have fasted longer, since chicks of parents delayed in the return to the colony die from starvation at an m of 3.0 kg. The long fast could be divided into three periods based on the changes in rate of decrease of m. The remarkable resistance of king penguin chicks to starvation may be partly explained by their ability to maintain protein sparing for as much as 4 mo, the duration of period II; plasma concentrations of uric acid, urea, and alanine were then minimum, 0.1, 0.4, and 0.4 mmol X l–1 respectively. Particular changes during this period, i.e., progressive increase of beta-hydroxybutyrate and decrease of glucose concentrations, might contribute to the efficiency of protein sparing. Period III was marked by a rise in protein utilization, plasma concentrations of uric acid, urea, and alanine increasing to 0.7, 1.5, and 0.8 mmol X l–1, respectively.

Effects of Season, Location, Species, and Sex on Hematologic and Plasma Biochemical Values and Body Mass in Free-ranging Grebes (Aechmophorus species)

2021 ◽  
Vol 35 (2) ◽  
Author(s):  
Nancy L. Anderson ◽  
Susan E. W. De La Cruz ◽  
Joseph K. Gaydos ◽  
Michael H. Ziccardi ◽  
Danielle J. Harvey
Keyword(s):  
Body Mass ◽  
Free Ranging

scholarly journals 22. The relation between orbits and physical characteristics of meteors

1968 ◽  
Vol 33 ◽  
pp. 217-235 ◽  
Author(s):  
Ľ. Kresák
Keyword(s):  
Major Axis ◽  
Progressive Increase ◽  
Physical Characteristics ◽  
The Other ◽  
Asteroid Belt ◽  
Angle Of Incidence ◽  
Semi Major Axis ◽  
Short Period ◽  
Broad Variety ◽  
Bona Fide

The relation of physical characteristics of meteors to their orbital elements is investigated using Harvard Super-Schmidt data. A set of characteristic indices is defined, allowing for the effects of geocentric velocity, angle of incidence, magnitude and mass, wherever a correction appears appropriate according to the correlations found by Jacchia et al. (1967). The medians for representative meteor samples are plotted in the semi-major axis/eccentricity diagram and the distribution of each parameter is derived. Although the differences are moderate compared to the measuring errors, six regions of different nature can be distinguished.The existence of two families of asteroidal meteors is indicated, one of them brought to crossing with the Earth's orbit by drag effects and the other by collision effects in the main asteroid belt. These meteors are characterized by low and uniform beginning heights, high fragmentation, low ablation, low deceleration, and bright wakes. A direct counterpart to this is represented by meteors moving in short-period orbits of higher eccentricity and shorter perihelion distance, which bear resemblance to the long-period and retrograde cometary meteors. Meteors with perihelion distances of less than 0·15 AU tend to resemble the bona fide asteroidal meteors by a progressive increase of fragmentation and decrease of reduced beginning heights and decelerations as the perihelion approaches the Sun. This is attributed to the selective destruction effects of solar radiation.With the exception of the Draconids, the mean characteristics of meteor showers agree well with those of sporadic meteors moving in similar orbits. It is suggested that the Draconid stream includes a broad variety of meteoric material and that the two peculiar Super-Schmidt meteors on record represent only the less resistive, short-lived component which has already been eliminated from the other showers.

Effects of canine heartworm (Dirofilaria immitis) on body condition and activity of free-ranging coyotes (Canis latrans)

2000 ◽  
Vol 78 (6) ◽  
pp. 1042-1051 ◽  
Author(s):  
Benjamin N Sacks ◽  
Karen M Blejwas
Keyword(s):  
Body Mass ◽  
Body Condition ◽  
Dirofilaria Immitis ◽  
Canis Latrans ◽  
Infected Group ◽  
Control Group ◽  
Canine Heartworm ◽  
Average Body Mass ◽  
Free Ranging ◽  
Average Body

We used radiotelemetry to study relationships among canine heartworm (Dirofilaria immitis) infection, body condition, and activity of free-ranging coyotes (Canis latrans). Average body mass at death was lower for 17 coyotes in a high-intensity infected group (mean = 33.6 heartworms) than for 18 coyotes in a control group (mean = 3.6 heartworms; p < 0.01). Coyotes in the infected group lost body mass at an average rate of 20% per year relative to the control group (p < 0.01). Bone marrow fat was negatively correlated with heartworm burden (R2 = 0.27; p < 0.01). Average body mass of coyotes at initial capture (i.e., potentially before infection) did not differ between infected and control groups (p = 0.90; 1–β = 0.70). Activity was negatively correlated with heartworm burden during the last 2 months of life (R2 = 0.30; p < 0.01), but no correlation was found 2–4 months before death. Activity of the infected group (n = 13) declined over time (p = 0.01), whereas no difference in activity was observed in the control group (n = 13; p = 0.50). Our findings indicate that heartworm infection reduced body condition and activity of coyotes but that nutritional status did not significantly affect susceptibility to infection.

Comparison of behaviour, body mass, haematocrit level, site fidelity and survival between infested and non-infested king penguin Aptenodytes patagonicus by ticks Ixodes uriae

Polar Biology ◽  
2003 ◽  
Vol 26 (6) ◽  
pp. 379-382 ◽  
Author(s):  
Michel Gauthier-Clerc ◽  
Stephan Mangin ◽  
Céline Le Bohec ◽  
Jean-Paul Gendner ◽  
Yvon Le Maho
Keyword(s):  
Body Mass ◽  
Site Fidelity ◽  
King Penguin ◽  
Haematocrit Level ◽  
Aptenodytes Patagonicus ◽  
Ixodes Uriae

scholarly journals Effect of Short Term Weight Loss on Appetite and Satiety Hormones in Overweight Female Adults

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1299-1299
Author(s):  
Kevin Finn ◽  
Venkataraghavan Ramamoorthy ◽  
Shayne Allan ◽  
Ebony Clint ◽  
Kayanna Dehaven ◽  
...  
Keyword(s):  
Weight Loss ◽  
Body Mass ◽  
Management Program ◽  
Energy Deficit ◽  
Short Term ◽  
Funding Sources ◽  
Short Period ◽  
Physical Activity Monitors ◽  
Group 2 ◽  
Group 1

Abstract Objectives The objective of this study was to test if short term weight loss has an effect on appetite and satiety hormones in a group of overweight female adults. It was hypothesized that participants who lost weight over a short period show changes in Ghrelin and Leptin. Methods Twelve healthy overweight female adults participating in a weight management program volunteered to wear physical activity monitors (FitBit Blaze), and log food intake over a period of 24 hours on the days when whole blood was drawn to measure plasma hormone concentrations. Energy deficit was determined through subtracting calories expended from the calories consumed. This causal-comparative study identified 7 women (Group 1) who lost at least 1% of their body mass in two weeks and compared their results to 5 women (Group 2) who did not.     Hormone Group 1 Group 2 Groups Total Groups Total Week 1 Week 3 Week 1 Week 3 Week 1 Week 3 P-values Ghrelin (pg/ml) 50.12 (49.96) 21. 79 (12.89) 149.07 (82.20) 79.21 (93.23) 91.35 (80.09) 45.72 (64.23) 0.017 Leptin (ng/mL) 10.08 (5.74) 9.12 (5.26) 7.56 (6.37) 7.73 (5.60) 9.03 (5.87) 8.54 (5.19) 0.481 Results Mean (SD) body mass for Group 1 decreased significantly (P &lt; 0.001)) from 85.80 (19.16) to 84.80 (19.21) kg, whereas Group 2 did not show significant change (68.62 + 5.42 vs. 68.70 + 5.46 kg). Mean (SD) energy deficits during the study period did not differ significantly between the groups. However there was a decreasing trend (P = 0.075) in Group 2 which had a 55 calories deficit in week 1 vs. 522 calories in week 3. Means (SD) hormone levels for each group by week (1 vs. 3) are given below. Ghrelin and Leptin levels did not differ between the weeks in each of the groups. However when groups were combined, significant differences in Ghrelin were observed between the weeks (P = 0.017). Similar findings were not observed for Leptin (P 0.481). Correlational analysis showed a significant moderate relationship (r = 0.655) between Ghrelin levels and Energy Deficit at the first week of the study. However this relationship was not significant in the Week 3. Conclusions There were significant associations between plasma Ghrelin levels and Energy Deficits during the beginning of the study, however, these relationships diminished over time. These findings need further research. Funding Sources The study was supported by the UCM Professional Enhancement Grant.

Allometry of the kidney: implications for the ontogeny of osmoregulation

1988 ◽  
Vol 255 (5) ◽  
pp. R760-R767 ◽  
Author(s):  
C. A. Beuchat ◽  
E. J. Braun
Keyword(s):  
Body Mass ◽  
Significant Role ◽  
Allometric Relationship ◽  
Ion Balance ◽  
Short Period ◽  
Sceloporus Jarrovi ◽  
Metanephric Kidney ◽  
Short Time

In reptiles, there are two pairs of kidneys at birth: the mesonephros and the metanephros. The metanephric kidney in reptiles, as in all amniote vertebrates, is retained as the functional kidney in adults. However, the reptilian mesonephros does not degenerate until after birth, and its function during this time is unknown. In neonates of the iguanid lizard Sceloporus jarrovi, the metanephric kidney is only 63% as large as predicted from the allometric relationship between kidney mass and body mass in adults. However, the kidney mass of neonatal lizards conforms to this prediction if the mesonephric and metanephric masses are combined. Some other amniote vertebrates appear to follow this pattern as well: in marsupials, which retain the mesonephros for a short period after birth, the sum of mesonephric and metanephric mass in neonates conforms to the allometry of kidney mass on body mass for adults. In contrast, the mesonephros of eutherian mammals is degenerate at birth and the metanephric kidney alone is of the predicted size. That the scaling of kidney mass in neonatal lizards and marsupials is the same as that of adults only if the mass of both the mesonephros and metanephros are combined suggests that the mesonephric kidney in these vertebrates plays a significant role in the regulation of water and ion balance during development and for at least a short time after birth.

Behavioural adjustments of wild-caught kangaroos to captivity

2017 ◽  
Vol 39 (2) ◽  
pp. 213 ◽  
Author(s):  
A. J. Munn ◽  
S. Phelan ◽  
M. Rigby ◽  
J. A. Roberts
Keyword(s):  
Wild Animal ◽  
Free Living ◽  
Novel Environment ◽  
Short Period ◽  
In Captivity ◽  
Free Ranging

It is important to understand how wild-caught animals may respond to captivity, and whether their behaviours in captivity are reflective of their wild counterparts. We observed the behaviour of wild-caught western grey kangaroos (Macropus fuliginosus) and red kangaroos (Osphranter rufus; formerly M. rufus) that were transferred to a large naturally vegetated enclosure. Observations were made on the first day of captivity and again after 7–10 days, and were compared with the behaviour of free-living kangaroos at the same locality and over the same period. We quantified feeding, moving, grooming and non-alert behaviours. Of these, grooming was higher in captive kangaroos than in free-living animals on the first day of captivity only, and was no different to that of wild animal by 7–10 days’ captivity. Such self-directed behaviour may be indicative of heightened distress for kangaroos on the first day of captivity, but it may also be indicative of grooming to eliminate contamination of human smells or debris following capture by darting and recovery. Overall, our findings indicate that after a short period of captivity, wild-caught kangaroos adjust to a novel environment relatively quickly, and animals from each species showed behaviour patterns comparable with free-ranging counterparts within 7–10 days after capture and captivity.

Seasonal patterns in body mass, body composition, and water transfer rates of free-ranging and captive black-tailed deer (Odocoileus hemionus sitkensis) in Alaska

1993 ◽  
Vol 71 (7) ◽  
pp. 1397-1404 ◽  
Author(s):  
Katherine L. Parker ◽  
Michael P. Gillingham ◽  
Thomas A. Hanley ◽  
Charles T. Robbins
Keyword(s):  
Body Composition ◽  
Body Mass ◽  
Body Fat ◽  
Energy Content ◽  
Odocoileus Hemionus ◽  
Water Transfer ◽  
Transfer Rates ◽  
In Captivity ◽  
Odocoileus Hemionus Sitkensis ◽  
Free Ranging

Body mass, body composition, and water transfer rates were determined over a continuous 2-year period in nine free-ranging Sitka black-tailed deer (Odocoileus hemionus sitkensis). Body masses showed a cyclical pattern, declined 14 – 31% between October and March, and were best described by a five-parameter, biologically based regression model. The amount of mass lost by black-tailed deer over winter depended on the peak body mass attained during fall. During winter, animals used 70 – 82% of their body fat and 10 – 15% of their protein reserves. Body fat was preferentially mobilized at rates 2.3 – 11.6 times higher than protein. Because of the higher energy content of fat, fat accounted for 83 – 92% of the catabolized energy. Water transfer rates varied seasonally with average summer values approximately four times those of winter; lactating deer had significantly higher rates of water transfer than nonlactating animals. Seasonal changes in all of the above parameters for wild deer were greater than those for eight deer of the same age in captivity.

scholarly journals Direct and indirect causal effects of heterozygosity on fitness-related traits in Alpine ibex

2015 ◽  
Vol 282 (1798) ◽  
pp. 20141873 ◽  
Author(s):  
Alice Brambilla ◽  
Iris Biebach ◽  
Bruno Bassano ◽  
Giuseppe Bogliani ◽  
Achaz von Hardenberg
Keyword(s):  
Path Analysis ◽  
Body Mass ◽  
Causal Effects ◽  
Parasite Resistance ◽  
Wild Populations ◽  
Capra Ibex ◽  
Alpine Ibex ◽  
Horn Growth ◽  
Nematode Eggs ◽  
Free Ranging

Heterozygosity–fitness correlations (HFCs) are a useful tool to investigate the effects of inbreeding in wild populations, but are not informative in distinguishing between direct and indirect effects of heterozygosity on fitness-related traits. We tested HFCs in male Alpine ibex ( Capra ibex ) in a free-ranging population (which suffered a severe bottleneck at the end of the eighteenth century) and used confirmatory path analysis to disentangle the causal relationships between heterozygosity and fitness-related traits. We tested HFCs in 149 male individuals born between 1985 and 2009. We found that standardized multi-locus heterozygosity (MLH), calculated from 37 microsatellite loci, was related to body mass and horn growth, which are known to be important fitness-related traits, and to faecal egg counts (FECs) of nematode eggs, a proxy of parasite resistance. Then, using confirmatory path analysis, we were able to show that the effect of MLH on horn growth was not direct but mediated by body mass and FEC. HFCs do not necessarily imply direct genetic effects on fitness-related traits, which instead can be mediated by other traits in complex and unexpected ways.

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