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Viblanc V. A. (2013).
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. (2012). Body Girth as an Alternative to Body Mass for Establishing Condition Indexes in Field Studies: A Validation in the King Penguin. Physiol. Biochem. Zool., 85(5), 533–542.
Abstract: ABSTRACT
Body mass and body condition are often tightly linked to animal health and fitness in the wild and thus are key measures for ecophysiologists and behavioral ecologists. In some animals,
such as large seabird species, obtaining indexes of structural size is relatively easy, whereas measuring body mass under specific field circumstances may be more of a challenge. Here, we
suggest an alternative, easily measurable, and reliable surrogate of body mass in field studies, that is, body girth. Using 234 free-living king penguins (Aptenodytes patagonicus) at various
stages of molt and breeding, we measured body girth under the flippers, body mass, and bill and flipper length. We found that body girth was strongly and positively related to body mass
in both molting (R2=0.91) and breeding (R2=0.73) birds,with the mean error around our predictions being 6.4%. Body girth appeared to be a reliable proxy measure of body mass because the relationship did not vary according to year and experimenter, bird sex, or stage within breeding groups. Body
girth was, however, a weak proxy of body mass in birds at the end of molt, probably because most of those birds had reached a critical depletion of energy stores. Body condition indexes
established from ordinary least squares regressions of either body girth or body mass on structural size were highly correlated (r=0.91), suggesting that body girth was as good as s
body mass in establishing body condition indexes in king penguins. Body girth may prove a useful proxy to body mass for estimating body condition in field investigations and could
likely provide similar information in other penguins and large animals that may be complicated to weigh in the wild.
Programme: 119
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Viavant M. (2011).
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Verron J, F. Birol, S. Calmant, A. Cazenave, B. Chapron, L. Eymard, J. M. Lefevre, F. Marin, F. Remy, F. Seyler, L. Testut, J. Vialard. (2013). SARAL/AltiKa: a satellite altimeter in Ka band for oceanographic science studies.
.
Abstract: ESA Living Planet Symposium, 9-13 Sep. 2013, Edinburgh (UK).
Programme: 688
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Verrier, D., Arnould,JP., Guinet, C. & Groscolas, R. (2007). Leptin in subantarctic fur seal pups: contribution to their adaptation to extreme fasting..
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Verrier, D., Arnould, JP., Atkinson, S., Guinet, C. & Groscolas, R. (2007). Leptin: new insights into the regulation of metabolism in free-ranging mammals..
Abstract: 53rd Scientific Meeting of the Australian Mammal Society, July 2-4, Armidale, Australia.
Programme: 119
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. (2011). The ontogeny of diving abilities in subantarctic fur seal pups: developmental trade-off in response to extreme fasting?
. Functional Ecology, 25(4), 818–828.
Keywords: aerobic dive limit, behavioural plasticity, diving behaviour, diving physiology, growth strategy, myoglobin, oxygen stores, weaning,
Programme: 119
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. (2011). The ontogeny of diving abilities in subantarctic fur seal pups: developmental trade-off in response to extreme fasting?
. 0269-8463, 25(4), 818–828.
Keywords: aerobic dive limit, behavioural plasticity, diving behaviour, diving physiology, growth strategy, myoglobin, oxygen stores, weaning,
Programme: 109
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. (2009). Physiological response to extreme fasting in subantarctic fur seal (Arctocephalus tropicalis) pups: metabolic rates, energy reserve utilization, and water fluxes.
. Am. J. Physiol. Regul. Integr. Comp. Physiol., 297(5), R1582–92.
Abstract: Surviving prolonged fasting requires various metabolic adaptations, such as energy and protein sparing, notably when animals are simultaneously engaged in energy-demanding processes such as growth. Due to the intermittent pattern of maternal attendance, subantarctic fur seal pups have to repeatedly endure exceptionally long fasting episodes throughout the 10-mo rearing period while preparing for nutritional independence. Their metabolic responses to natural prolonged fasting (33.4 +/- 3.3 days) were investigated at 7 mo of age. Within 4-6 fasting days, pups shifted into a stage of metabolic economy characterized by a minimal rate of body mass loss (0.7%/day) and decreased resting metabolic rate (5.9 +/- 0.1 ml O(2)xkg(-1)xday(-1)) that was only 10% above the level predicted for adult terrestrial mammals. Field metabolic rate (289 +/- 10 kJxkg(-1)xday(-1)) and water influx (7.9 +/- 0.9 mlxkg(-1)xday(-1)) were also among the lowest reported for any young otariid, suggesting minimized energy allocation to behavioral activity and thermoregulation. Furthermore, lean tissue degradation was dramatically reduced. High initial adiposity (>48%) and predominant reliance on lipid catabolism likely contributed to the exceptional degree of protein sparing attained. Blood chemistry supported these findings and suggested utilization of alternative fuels, such as beta-hydroxybutyrate and de novo synthesized glucose from fat-released glycerol. Regardless of sex and body condition, pups tended to adopt a convergent strategy of extreme energy and lean body mass conservation that appears highly adaptive for it allows some tissue growth during the repeated episodes of prolonged fasting they experience throughout their development.
Keywords: 3-Hydroxybutyric Acid, 3-Hydroxybutyric Acid: metabolism, Adaptation, Physiological, Adaptation, Physiological: physiology, Animals, Animals, Newborn, Animals, Newborn: physiology, Basal Metabolism, Basal Metabolism: physiology, Body Composition, Body Composition: physiology, Body Mass Index, Body Temperature, Body Temperature: physiology, Energy Metabolism, Energy Metabolism: physiology, Fasting, Fasting: physiology, Female, Fur Seals, Fur Seals: physiology, Lipid Metabolism, Lipid Metabolism: physiology, Male, Seasons, Water, Water: metabolism,
Programme: 109
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. (2009). Physiological response to extreme fasting in subantarctic fur seal (Arctocephalus tropicalis) pups: metabolic rates, energy reserve utilization, and water fluxes.
. Am. J. Physiol. Regul. Integr. Comp. Physiol., 297(5), R1582–92.
Abstract: Surviving prolonged fasting requires various metabolic adaptations, such as energy and protein sparing, notably when animals are simultaneously engaged in energy-demanding processes such as growth. Due to the intermittent pattern of maternal attendance, subantarctic fur seal pups have to repeatedly endure exceptionally long fasting episodes throughout the 10-mo rearing period while preparing for nutritional independence. Their metabolic responses to natural prolonged fasting (33.4 +/- 3.3 days) were investigated at 7 mo of age. Within 4-6 fasting days, pups shifted into a stage of metabolic economy characterized by a minimal rate of body mass loss (0.7%/day) and decreased resting metabolic rate (5.9 +/- 0.1 ml O(2)xkg(-1)xday(-1)) that was only 10% above the level predicted for adult terrestrial mammals. Field metabolic rate (289 +/- 10 kJxkg(-1)xday(-1)) and water influx (7.9 +/- 0.9 mlxkg(-1)xday(-1)) were also among the lowest reported for any young otariid, suggesting minimized energy allocation to behavioral activity and thermoregulation. Furthermore, lean tissue degradation was dramatically reduced. High initial adiposity (>48%) and predominant reliance on lipid catabolism likely contributed to the exceptional degree of protein sparing attained. Blood chemistry supported these findings and suggested utilization of alternative fuels, such as beta-hydroxybutyrate and de novo synthesized glucose from fat-released glycerol. Regardless of sex and body condition, pups tended to adopt a convergent strategy of extreme energy and lean body mass conservation that appears highly adaptive for it allows some tissue growth during the repeated episodes of prolonged fasting they experience throughout their development.
Keywords: 3-Hydroxybutyric Acid, 3-Hydroxybutyric Acid: metabolism, Adaptation, Physiological, Adaptation, Physiological: physiology, Animals, Animals, Newborn, Animals, Newborn: physiology, Basal Metabolism, Basal Metabolism: physiology, Body Composition, Body Composition: physiology, Body Mass Index, Body Temperature, Body Temperature: physiology, Energy Metabolism, Energy Metabolism: physiology, Fasting, Fasting: physiology, Female, Fur Seals, Fur Seals: physiology, Lipid Metabolism, Lipid Metabolism: physiology, Male, Seasons, Water, Water: metabolism,
Programme: 119
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