| [the fast of the emperor penguin (aptenodytes patagonica j.f. miller) on the isle of the possession (46 degrees 25' south, 51 degrees 045' east]. | during the fast, ponderal decrease and energy expenditure of captive king penguins are minimal for the incubating adults, and maximal for the moulting birds who are producing their new plumage and whose insulation is reduced at that time. whatever their conditions, the slope of the ponderal decrease curve is uniform before reaching a critical zone. on the other hand, it is independent of the seasons for the unemployed birds. | 1975 | 808325 |
| [the energy metabolism of the emperor penguin (aptendodytes patagonica j. f. miller) in ambient natural conditions]. | in natural ambient conditions at possession island the resting metabolism of the emancipated king penguin is 50.40 kcal/kg/d. a bird whose insulation is good and which maintains its stomachic temperature at a high level can reduce its heat production by 42% during the long fasting periods which characterize its reproductive cycle, in particular by social and individual thermoregulating behaviour. | 1976 | 816534 |
| early changes in plasma hormones and metabolites during fasting in king penguin chicks. | chicks of the king penguin (aptenodytes patagonica) can tolerate a fast of 4-6 months during the subantarctic winter. the aim of this work was to study their initial response to food deprivation. nine chicks were starved for 18 days. two phases of starvation were defined according to changes in the specific daily loss in body mass: it decreased by 92% in phase i (6.6 +/- 0.3 days) and remained steady and low in phase ii. phase i was marked by a large decline in protein utilization, indicated by ... | 1988 | 3220986 |
| notes on parasites in penguins (spheniscidae) and petrels (procellariidae) in the antarctic and sub-antarctic. | blood smears were examined from 143 penguins of four species (aptenodytes patagonicus, eudyptes chrysolophus, e. schlegeli, and pygoscelis gentoo) from sub-antarctic macquarie island and heard island. no blood parasites were reported. the vectors of hepatozoon albatrossi (reported from three species of albatross) are probably shared by penguins, and it is suggested that the latter are not susceptible to infection with this protozoan. cestodes of the genus tetrabothrius were present in large numb ... | 1988 | 3352088 |
| [newcastle disease a king penguin (aptenodytes patachonica)]. | | 1963 | 5896739 |
| a survey of virus infection in sub-antarctic penguins on macquarie island, southern ocean. | serums from 1002 penguins of 4 species on macquarie island, a sub-antarctic island in the southern ocean, were examined for antibody to newcastle disease virus (ndv), influenza a virus, avian paramyxovirus, alphavirus and flavivirus. no evidence of haemagglutination-inhibition antibody to influenza a virus or alphavirus was detected. serums from 6% of royal penguins sampled gave positive reactions to ndv while the other 3 species were negative. antibody to a flavivirus and an avian paramyxovirus ... | 1981 | 7340785 |
| seabirds as monitors of upper-ocean thermal structure. king penguins at the antarctic polar front, east of kerguelen sector. | the main objective of this work was to assess the potential of diving birds to monitor the hydrographic features near the antarctic polar front. we compared the temperature/depth profiles recorded by instrumented king penguins aptenodytes patagonicus at kerguelen islands (south indian ocean) with the oceanographic and remote sensing (satellite) data available for the same area during the same season. the birds were equipped with time/depth/temperature recorders or argos transmitters. in addition ... | 2000 | 10803349 |
| penguins use the two-voice system to recognize each other. | the sound-producing structure in birds is the syrinx, which is usually a two-part organ located at the junction of the bronchi. as each branch of the syrinx produces sound independently, many birds have two acoustic sources. thirty years ago, we had anatomical, physiological and acoustical evidence of this two-voice phenomenon but no function was known. in songbirds, often these two voices with their respective harmonics are not activated simultaneously but they are obvious in large penguins and ... | 2000 | 10885512 |
| energetic costs of surface swimming and diving of birds. | the energetic costs of swimming at the surface (swimming) and swimming underwater (diving) are compared in tufted ducks (aythya fuligula) and three species of penguins, the gentoo (pygoscelis papua), the king (aptenodytes patagonicus), and the emperor (aythya forsteri). ducks swim on the surface and use their webbed feet as paddles, whereas penguins tend to swim just below the surface and use their flippers as hydrofoils, the latter being much more efficient. penguins are more streamlined in sha ... | 2000 | 11121344 |
| life cycle of the tick ixodes uriae in penguin colonies: relationships with host breeding activity. | a survey of the temporal pattern of population structure and feeding activity of the seabird tick ixodes uriae was conducted for the first time in two host species colonies: king penguin (aptenodytes patagonicus halli) and macaroni penguin (eudyptes chrysolophus chrysolophus). the life cycle of the tick was investigated over 3 years in a king penguin colony and 2 years in a macaroni penguin colony at possession island (crozet archipelago). there was a marked seasonal feeding activity pattern of ... | 2001 | 11429167 |
| development of an indirect elisa for the detection of serum antibodies to aspergillus fumigatus in captive penguins. | aspergillosis is a significant cause of mortality in captive penguins (sphenisciformes). an indirect elisa for the detection of aspergillus fumigatus-specific immunoglobulin in penguins was developed and standardised by making use of a family-specific antiserum (anti-aptenodyptes patagonica patagonicus). the results were calculated quantitatively as elisa units, derived by polynomial regression analysis, and semi-quantitatively as end titres. serum samples from 61 captive penguins were tested wi ... | 2002 | 12017526 |
| fa composition of heart and skeletal muscle during embryonic development of the king penguin. | since the yolk lipids of the king penguin (aptenodytes patagonicus) naturally contain the highest concentrations of dha and epa yet reported for the eggs of any avian species, the effects of this (n-3)-rich yolk on the fa profiles of the embryonic heart and skeletal muscle were investigated. the concentrations (mg/g wet tissue) of phospholipid (pl) in the developing heart and leg muscle of the penguin doubled between days 27 and 55 from the beginning of egg incubation (i.e., from the halfway sta ... | 2002 | 12030322 |
| foraging areas of king penguins from macquarie island in relation to a marine protected area. | twenty-three king penguins (aptenodytes patagonicus) from macquarie island were tracked by satellite during the late incubation period in 1998-1999 to determine the overlap of the foraging zone of king penguins with an area to be declared a marine protected area (mpa) near the island. while all penguins left the colony in an easterly direction and traveled clockwise back to the island, three penguins foraged in the northern parts of the general foraging area and stayed north of 56 degrees s. the ... | 2002 | 12180180 |
| establishment of the fatty acid profile of the brain of the king penguin (aptenodytes patagonicus) at hatch: effects of a yolk that is naturally rich in n-3 polyunsaturates. | because the yolk lipids of the king penguin (aptenodytes patagonicus) contain the highest concentrations of long-chain n-3 polyunsaturated fatty acids yet reported for an avian species, the consequences for the establishment of the brain's fatty acid profile in the embryo were investigated. to place the results in context, the fatty acid compositions of yolk lipid and brain phospholipid of the king penguin were compared with those from three other species of free-living birds. the proportions of ... | 2003 | 12794672 |
| superoxide activates a gdp-sensitive proton conductance in skeletal muscle mitochondria from king penguin (aptenodytes patagonicus). | we present the partial nucleotide sequence of the avian uncoupling protein (avucp) gene from king penguin (aptenodytes patagonicus), showing that the protein is 88-92% identical to chicken (gallus gallus), turkey (meleagris gallopavo), and hummingbird (eupetomena macroura). we show that superoxide activates the proton conductance of mitochondria isolated from king penguin skeletal muscle. gdp abolishes the superoxide-activated proton conductance, indicating that it is mediated via avucp. in the ... | 2003 | 14651968 |
| plasma thyroid hormone pattern in king penguin chicks: a semi-altricial bird with an extended posthatching developmental period. | plasma concentrations of thyroid hormones (th) were investigated during the extended posthatching developmental period (approximately 11 months) of a semi-altricial bird species, the king penguin (aptenodytes patagonicus). the first period of growth in summer was marked by a progressive rise in plasma t4 concentration that paralleled rapid increases in body mass and in structural and down growth. by contrast, plasma t3 concentration had already reached adult levels in newly hatched chicks and di ... | 2004 | 15081840 |
| solution structure of spheniscin, a beta-defensin from the penguin stomach. | recently two beta-defensins, named spheniscins, have been isolated from the stomach content of the king penguin (aptenodytes patagonicus), which is capable of preserving food for several weeks during egg incubation (thouzeau, c., le maho, y., froget, g., sabatier, l., le bohec, c., hoffmann, j. a., and bulet, p. (2003) j. biol. chem. 278, 51053-51058). it has been proposed that, in combination with other antimicrobial peptides, spheniscins may be involved in this long term preservation of food i ... | 2004 | 15123713 |
| avian antimicrobial peptides: the defense role of beta-defensins. | avian antimicrobial peptides, classified as beta-defensins, have been identified from bloods of chicken, turkey, and ostrich; epithelial cells of chicken and turkey; and king penguin stomach contents. beta-defensins are a family of antimicrobial peptides characterized by six cysteine residues forming beta-defensin motifs that are also found in bovine, ovine, pig, and human. these peptides are active against a wide range of microorganisms including gram-positive and gram-negative bacteria, fungi, ... | 2004 | 15381059 |
| gene expression, tissue distribution and potential physiological role of uncoupling protein in avian species. | whole-body energy homeostasis and food intake control are essential for an economically sound selection for growth in poultry. the cellular and molecular mechanisms that regulate and link food intake, energy expenditure and energy balance are still poorly understood in poultry. mitochondrial uncoupling protein-1 (ucp-1) is known to uncouple respiration from atp synthesis by short circuiting the inward proton flow, resulting in heat production. its role seems quite well established in adaptive th ... | 2004 | 15556382 |
| mercury concentrations in king penguin (aptenodytes patagonicus) feathers at crozet islands (sub-antarctic): temporal trend between 1966--1974 and 2000--2001. | remote sub-antarctic islands and their wildlife may be contaminated by mercury via atmospheric and oceanic currents. because of mercury's high toxicity and its capacity to be biomagnified in marine food chains, top predators like seabirds may be threatened by secondary poisoning. the present study provides data regarding mercury concentrations in breast feathers sampled in 2000 and 2001 on king penguins (aptenodytes patagonicus) living at crozet islands. these contemporary concentrations were co ... | 2005 | 15683175 |
| corticosterone in relation to body mass in adelie penguins (pygoscelis adeliae) affected by unusual sea ice conditions at ross island, antarctica. | penguins naturally fast each year during breeding and again whilst moulting, and may lose more than 40% of body mass during a fast. fasting in emperor (aptenodytes forsteri) and king (aptenodytes patagonicus) penguins has been divided into three phases, with phase iii characterised by an increased rate of body mass loss, increased plasma corticosterone concentrations, and a change in behaviour leading to abandonment of the breeding attempt and return to sea to feed. initial corticosterone concen ... | 2006 | 16876799 |
| ultraviolet reflecting photonic microstructures in the king penguin beak. | king and emperor penguins (aptenodytes patagonicus and aptenodytes forsteri) are the only species of marine birds so far known to reflect ultraviolet (uv) light from their beaks. unlike humans, most birds perceive uv light and several species communicate using the near uv spectrum. indeed, uv reflectance in addition to the colour of songbird feathers has been recognized as an important signal when choosing a mate. the king penguin is endowed with several highly coloured ornaments, notably its be ... | 2005 | 17148195 |
| low mhc variation in the endangered galápagos penguin (spheniscus mendiculus). | the major histocompatibility complex (mhc) is one of the most polymorphic regions of the genome, likely due to balancing selection acting to maintain alleles over time. lack of mhc variability has been attributed to factors such as genetic drift in small populations and relaxed selection pressure. the galápagos penguin (spheniscus mendiculus), endemic to the galápagos islands, is the only penguin that occurs on the equator. it relies upon cold, nutrient-rich upwellings and experiences severe pop ... | 2007 | 17457582 |
| population dynamics in a long-lived seabird: i. impact of breeding activity on survival and breeding probability in unbanded king penguins. | understanding the trade-off between current reproductive effort, future survival and future breeding attempts is crucial for demographic analyses and life history studies. we investigated this trade-off in a population of king penguins (aptenodytes patagonicus) marked individually with transponders using multistate capture-recapture models. this colonial seabird species has a low annual proportion of non-breeders (13%), despite a breeding cycle which lasts over 1 year. to draw inferences about t ... | 2007 | 17922711 |
| is fledging in king penguin chicks related to changes in metabolic or endocrinal status? | this study examines the possibility that metabolic or endocrinal factors initiate fledging in the king penguin, a semi-altricial seabird species breeding a single chick on the ground. chick fledging (departure to sea) occurred 5d after completion of the molt. it was preceded by a 16d fasting period and by a 7-fold increase in locomotor activity. from the measurement of the plasma concentration of metabolites and of glucagon and insulin, pre-fledging king penguin chicks were found to adapt to fas ... | 2008 | 18155218 |
| concurrent infection with clostridium and plasmodium in a captive king penguin aptenodytes patagonicus. | concurrent infection with plasmodium relictum and clostridium perfringens type b was diagnosed in a king penguin (aptenodytes patagonicus) that died in the national zoological gardens, pretoria. macro- and microscopic pathological changes were mainly due to c. perfringens. the relative significance of the two pathogens is discussed. | 1994 | 18671104 |
| ticks associated with macquarie island penguins carry arboviruses from four genera. | macquarie island, a small subantarctic island, is home to rockhopper, royal and king penguins, which are often infested with the globally distributed seabird tick, ixodes uriae. a flavivirus, an orbivirus, a phlebovirus, and a nairovirus were isolated from these ticks and partial sequences obtained. the flavivirus was nearly identical to gadgets gully virus, isolated some 30 year previously, illustrating the remarkable genetic stability of this virus. the nearest relative to the orbivirus (for w ... | 2009 | 19194498 |
| transcriptome analysis in non-model species: a new method for the analysis of heterologous hybridization on microarrays. | recent developments in high-throughput methods of analyzing transcriptomic profiles are promising for many areas of biology, including ecophysiology. however, although commercial microarrays are available for most common laboratory models, transcriptome analysis in non-traditional model species still remains a challenge. indeed, the signal resulting from heterologous hybridization is low and difficult to interpret because of the weak complementarity between probe and target sequences, especially ... | 2010 | 20509979 |
| reliability of flipper-banded penguins as indicators of climate change. | in 2007, the intergovernmental panel on climate change highlighted an urgent need to assess the responses of marine ecosystems to climate change. because they lie in a high-latitude region, the southern ocean ecosystems are expected to be strongly affected by global warming. using top predators of this highly productive ocean (such as penguins) as integrative indicators may help us assess the impacts of climate change on marine ecosystems. yet most available information on penguin population dyn ... | 2011 | 21228875 |
| septicaemia caused by edwardsiella tarda and plesiomonas shigelloides in captive penguin chicks. | three cases of fatal septicaemia due to plesiomonas shigelloides and one due to edwardsiella tarda were diagnosed in newborn penguins from the basle zoo, switzerland from 2003 to 2007. the affected penguins were of two different species (king penguin, aptenodytes patagonicus, and african penguin, spheniscus demersus) and between 2 and 10 days old at the time of death. the causative agents, e. tarda and p. shigelloides are ubiquitous bacteria which are reported to be present in the normal intesti ... | 2011 | 21360449 |
| initial insights into the structure-activity relationships of avian defensins. | numerous β-defensins have been identified in birds and the potential use of these peptides as alternatives to antibiotics has been proposed, in particular to fight antibiotic-resistant and zoonotic bacterial species. little is known about the mechanism of antibacterial activity of avian β-defensins (avbds), and the present work was carried out to obtain initial insights into the involvement of structural features or specific residues in the antimicrobial activity of chicken avbd2. chicken avbd2 ... | 2011 | 22205704 |
| vision of the humboldt penguin (spheniscus humboldti) in air and water. | refractive states measured by retinoscopy and photorefraction indicate that the eyes of the humboldt penguin, spheniscus humboldti, are approximately emmetropic in air and water. extensive myopia in air, as predicted by earlier authors and by a recent anatomical study, is non-existent. photorefractive measurements of the refractive state, in water, of the humboldt penguin indicate that it can accommodate sufficiently to make up the loss of the refractive power of the cornea. the cornea of the hu ... | 2010 | 2881308 |
| it costs to be clean and fit: energetics of comfort behavior in breeding-fasting penguins. | birds may allocate a significant part of time to comfort behavior (e.g., preening, stretching, shaking, etc.) in order to eliminate parasites, maintain plumage integrity, and possibly reduce muscular ankylosis. understanding the adaptive value of comfort behavior would benefit from knowledge on the energy costs animals are willing to pay to maintain it, particularly under situations of energy constraints, e.g., during fasting. we determined time and energy devoted to comfort activities in freely ... | 2011 | 21818253 |
| first detection of borrelia burgdorferi sensu lato dna in king penguins (aptenodytes patagonicus halli). | the hard tick ixodes uriae parasitises a wide range of seabird species in the circumpolar areas of both northern and southern hemispheres and has been shown to be infected with borrelia burgdorferi sensu lato, the bacterial agents of lyme borreliosis. although it is assumed that seabirds represent viable reservoir hosts, direct demonstrations of infection are limited to a single study from the northern hemisphere. here, the blood of 50 tick-infested adult king penguins (aptenodytes patagonicus h ... | 2014 | 25150726 |
| transcriptomic data analysis and differential gene expression of antioxidant pathways in king penguin juveniles (aptenodytes patagonicus) before and after acclimatization to marine life. | in this article, we present differentially expressed gene profiles in the pectoralis muscle of wild juvenile king penguins that were either naturally acclimated to cold marine environment or experimentally immersed in cold water as compared with penguin juveniles that never experienced cold water immersion. transcriptomic data were obtained by hybridizing penguins total cdna on affymetrix genechip chicken genome arrays and analyzed using maxrs algorithm, "transcriptome analysis in non-model spec ... | 2016 | 27752524 |
| use of propofol for induction and maintenance of anesthesia in a king penguin ( aptenodytes patagonicus ) undergoing magnetic resonance imaging. | anesthesia protocols for patients with intracranial lesions need to provide hemodynamic stability, preserve cerebrovascular autoregulation, avoid increases in intracranial pressure, and facilitate a rapid recovery. propofol total intravenous anesthesia (tiva) maintains cerebral blood flow autoregulation and is considered superior to inhalant agents as an anesthetic protocol for patients with intracranial lesions. a propofol-based tiva subsequent to premedication with medetomidine and diazepam wa ... | 2016 | 27736225 |
| dispersal in the sub-antarctic: king penguins show remarkably little population genetic differentiation across their range. | seabirds are important components of marine ecosystems, both as predators and as indicators of ecological change, being conspicuous and sensitive to changes in prey abundance. to determine whether fluctuations in population sizes are localised or indicative of large-scale ecosystem change, we must first understand population structure and dispersal. king penguins are long-lived seabirds that occupy a niche across the sub-antarctic zone close to the polar front. colonies have very different histo ... | 2016 | 27733109 |
| early diving behaviour in juvenile penguins: improvement or selection processes. | the early life stage of long-lived species is critical to the viability of population, but is poorly understood. longitudinal studies are needed to test whether juveniles are less efficient foragers than adults as has been hypothesized. we measured changes in the diving behaviour of 17 one-year-old king penguins aptenodytes patagonicus at crozet islands (subantartic archipelago) during their first months at sea, using miniaturized tags that transmitted diving activity in real time. we also equip ... | 2016 | 27484650 |
| an evaluation of infrared thermography for detection of bumblefoot (pododermatitis) in penguins. | the objective of this study was to evaluate infrared thermography as a noninvasive screening tool for detection of pododermatitis during the developing and active stages of disease in three species of penguins: king penguin (aptenodytes patagonicus) , macaroni penguin (eudyptes chrysolophus), and rockhopper penguin (eudyptes chrysocome). in total, 67 penguins were examined every 3 mo over a 15-mo period. at each exam, bumblefoot lesions were characterized and measured, and a timed series of ther ... | 2016 | 27468019 |
| hormetic response triggers multifaceted anti-oxidant strategies in immature king penguins (aptenodytes patagonicus). | repeated deep dives are highly pro-oxidative events for air-breathing aquatic foragers such as penguins. at fledging, the transition from a strictly terrestrial to a marine lifestyle may therefore trigger a complex set of anti-oxidant responses to prevent chronic oxidative stress in immature penguins but these processes are still undefined. by combining in vivo and in vitro approaches with transcriptome analysis, we investigated the adaptive responses of sea-acclimatized (sa) immature king pengu ... | 2016 | 27449544 |
| breeding status affects the hormonal and metabolic response to acute stress in a long-lived seabird, the king penguin. | stress responses are suggested to physiologically underlie parental decisions promoting the redirection of behaviour away from offspring care when survival is jeopardized (e.g., when facing a predator). besides this classical view, the "brood-value hypothesis" suggests that parents' stress responses may be adaptively attenuated to increase fitness, ensuring continued breeding when the relative value of the brood is high. here, we test the brood-value hypothesis in breeding king penguins (aptenod ... | 2016 | 27449343 |
| basal metabolic rate of the black-faced sheathbill (chionis minor): intraspecific variation in a phylogenetically distinct island endemic. | metabolic rate is a fundamental characteristic of all organisms. it covaries most significantly with activity, body mass, seasonality, and temperature. nonetheless, substantial additional variation in metabolic rate, especially either resting rate or basal rate, is associated with a range of factors including phylogenetic position, ecological distinctiveness, range position, and diet. understanding this variation is a key goal of physiological ecology. the black-faced sheathbill is a phylogeneti ... | 2017 | 27082724 |
| lipid-induced thermogenesis is up-regulated by the first cold-water immersions in juvenile penguins. | the passage from shore to marine life is a critical step in the development of juvenile penguins and is characterized by a fuel selection towards lipid oxidation concomitant to an enhancement of lipid-induced thermogenesis. however, mechanisms of such thermogenic improvement at fledging remain undefined. we used two different groups of pre-fledging king penguins (aptenodytes patagonicus) to investigate the specific contribution of cold exposure during water immersion to lipid metabolism. terrest ... | 2016 | 26924130 |
| large-scale climatic anomalies affect marine predator foraging behaviour and demography. | determining the links between the behavioural and population responses of wild species to environmental variations is critical for understanding the impact of climate variability on ecosystems. using long-term data sets, we show how large-scale climatic anomalies in the southern hemisphere affect the foraging behaviour and population dynamics of a key marine predator, the king penguin. when large-scale subtropical dipole events occur simultaneously in both subtropical southern indian and atlanti ... | 2015 | 26506134 |
| king penguins can detect two odours associated with conspecifics. | recent studies on olfaction in penguins have focused on their use of odours while foraging. it has been proposed for some seabirds that an olfactory landscape shaped by odours coming from feeding areas exists. islands and colonies, however, may also contribute to the olfactory landscape and may act as an orienting map. to test sensitivities to a colony scent we studied whether king penguins (aptenodytes patagonicus) could detect the smell of sand, feathers or feces by holding presentations benea ... | 2015 | 26385329 |
| modulation of heart rate response to acute stressors throughout the breeding season in the king penguin aptenodytes patagonicus. | 'fight-or-flight' stress responses allow animals to cope adaptively to sudden threats by mobilizing energy resources and priming the body for action. because such responses can be costly and redirect behavior and energy from reproduction to survival, they are likely to be shaped by specific life-history stages, depending on the available energy resources and the commitment to reproduction. here, we consider how heart rate (hr) responses to acute stressors are affected by the advancing breeding s ... | 2015 | 25883375 |
| penguin lungs and air sacs: implications for baroprotection, oxygen stores and buoyancy. | the anatomy and volume of the penguin respiratory system contribute significantly to pulmonary baroprotection, the body o2 store, buoyancy and hence the overall diving physiology of penguins. therefore, three-dimensional reconstructions from computerized tomographic (ct) scans of live penguins were utilized to measure lung volumes, air sac volumes, tracheobronchial volumes and total body volumes at different inflation pressures in three species with different dive capacities [adélie (pygoscelis ... | 2015 | 25740902 |
| spatial heterogeneity as a genetic mixing mechanism in highly philopatric colonial seabirds. | how genetic diversity is maintained in philopatric colonial systems remains unclear, and understanding the dynamic balance of philopatry and dispersal at all spatial scales is essential to the study of the evolution of coloniality. in the king penguin, aptenodytes patagonicus, return rates of post-fledging chicks to their natal sub-colony are remarkably high. empirical studies have shown that adults return year after year to their previous breeding territories within a radius of a few meters. ye ... | 2015 | 25680103 |
| inter-annual variability of fledgling sex ratio in king penguins. | as the number of breeding pairs depends on the adult sex ratio in a monogamous species with biparental care, investigating sex-ratio variability in natural populations is essential to understand population dynamics. using 10 years of data (2000-2009) in a seasonally monogamous seabird, the king penguin (aptenodytes patagonicus), we investigated the annual sex ratio at fledging, and the potential environmental causes for its variation. over more than 4000 birds, the annual sex ratio at fledging w ... | 2014 | 25493708 |
| reassessment of the cardio-respiratory stress response, using the king penguin as a model. | research in to short-term cardio-respiratory changes in animals in reaction to a psychological stressor typically describes increases in rate of oxygen consumption (v̇(o2)) and heart rate. consequently, the broad consensus is that they represent a fundamental stressor response generalizable across adult species. however, movement levels can also change in the presence of a stressor, yet studies have not accounted for this possible confound on heart rate. thus the direct effects of psychological ... | 2015 | 25384111 |
| maternal telomere length inheritance in the king penguin. | telomeres are emerging as a biomarker for ageing and survival, and are likely important in shaping life-history trade-offs. in particular, telomere length with which one starts in life has been linked to lifelong survival, suggesting that early telomere dynamics are somehow related to life-history trajectories. this result highlights the importance of determining the extent to which telomere length is inherited, as a crucial factor determining early life telomere length. given the scarcity of sp ... | 2015 | 25052413 |
| a dual mechanism involved in membrane and nucleic acid disruption of avbd103b, a new avian defensin from the king penguin, against salmonella enteritidis cvcc3377. | the food-borne bacterial gastrointestinal infection is a serious public health threat. defensins are evolutionarily conserved innate immune components with broad-spectrum antibacterial activity that do not easily induce resistance. avbd103b, an avian defensin with potent activity against salmonella enteritidis, was isolated from the stomach contents of the king penguin (aptenodytes patagonicus). to elucidate further the antibacterial mechanism of avbd103b, its effect on the s. enteritidis cvcc33 ... | 2014 | 24981062 |
| influence of fasting during moult on the faecal microbiota of penguins. | many seabirds including penguins are adapted to long periods of fasting, particularly during parts of the reproductive cycle and during moult. however, the influence of fasting on the gastrointestinal (gi) microbiota has not been investigated in seabirds. therefore, the present study aimed to examine the microbial composition and diversity of the gi microbiota of fasting little (eudyptula minor) and king penguins (aptenodytes patagonicus) penguins during early and late moult. the results from th ... | 2014 | 24979619 |
| king penguin demography since the last glaciation inferred from genome-wide data. | how natural climate cycles, such as past glacial/interglacial patterns, have shaped species distributions at the high-latitude regions of the southern hemisphere is still largely unclear. here, we show how the post-glacial warming following the last glacial maximum (ca 18 000 years ago), allowed the (re)colonization of the fragmented sub-antarctic habitat by an upper-level marine predator, the king penguin aptenodytes patagonicus. using restriction site-associated dna sequencing and standard mit ... | 2014 | 24920481 |
| post-fledging dispersal of king penguins (aptenodytes patagonicus) from two breeding sites in the south atlantic. | most studies concerning the foraging ecology of marine vertebrates are limited to breeding adults, although other life history stages might comprise half the total population. for penguins, little is known about juvenile dispersal, a period when individuals may be susceptible to increased mortality given their naïve foraging behaviour. therefore, we used satellite telemetry to study king penguin fledglings (n = 18) from two sites in the southwest atlantic in december 2007. the two sites differed ... | 2014 | 24828545 |
| mitochondrial phenotypic flexibility enhances energy savings during winter fast in king penguin chicks. | energy conservation is a key priority for organisms that live in environments with seasonal shortages in resource supplies or that spontaneously fast during their annual cycle. the aim of this study was to determine whether the high fasting endurance of winter-acclimatized king penguin chicks (aptenodytes patagonicus) is associated with an adjustment of mitochondrial bioenergetics in pectoralis muscle, the largest skeletal muscle in penguins. the rates of mitochondrial oxygen consumption, and at ... | 2014 | 24803465 |
| stress hormones in relation to breeding status and territory location in colonial king penguin: a role for social density? | because glucocorticoid (stress) hormones fundamentally affect various aspects of the behaviour, life history and fitness of free-living vertebrates, there is a need to understand the environmental factors shaping their variation in natural populations. here, we examined whether spatial heterogeneity in breeding territory quality affected the stress of colonial king penguin (aptenodytes patagonicus). we assessed the effects of local climate (wind, sun and ambient temperature) and social condition ... | 2014 | 24744279 |
| high-throughput gender identification of penguin species using melting curve analysis. | most species of penguins are sexual monomorphic and therefore it is difficult to visually identify their genders for monitoring population stability in terms of sex ratio analysis. in this study, we evaluated the suitability using melting curve analysis (mca) for high-throughput gender identification of penguins. preliminary test indicated that the griffiths's p2/p8 primers were not suitable for mca analysis. based on sequence alignment of chromo-helicase-dna binding protein (chd)-w and chd-z ge ... | 2014 | 24555797 |
| semen characterization, seasonality of production, and in vitro sperm quality after chilled storage and cryopreservation in the king penguin (aptenodytes patagonicus). | research was conducted to examine seasonal seminal traits and to establish short-term and long-term sperm preservation methods in the king penguin (aptenodytes patagonicus) for use in genome banking and artificial insemination (ai). spermic ejaculates (n = 87) obtained using a cooperative method were collected across multiple (n = 6, male 1) and a single (male 2) breeding season(s). non-contaminated ejaculates (n = 69) were 0.36 ± 0.32 ml at 56.3 ± 62.7 × 10(7) sperm/ml with 85.3 ± 10.6% total ... | 2014 | 24395205 |
| blood oxygen- and carbon dioxide-carrying properties in captive penguins: effects of moulting and inter-specific comparison. | venous blood gas-carrying properties were compared in the three captive species of penguins (king, gentoo and rockhopper) at océanopolis (france). captivity permitted to control environmental influences. given their different ecology and diving behaviour in the wild, it was wondered whether milder conditions and dive privation have repercussions on parameters determining oxygen storage and acid-base status of these birds. in addition, this work provided the opportunity to study the effects of mo ... | 2014 | 24231467 |
| vibrational spectroscopic analyses of unique yellow feather pigments (spheniscins) in penguins. | many animals extract, synthesize and refine chemicals for colour display, where a range of compounds and structures can produce a diverse colour palette. feather colours, for example, span the visible spectrum and mostly result from pigments in five chemical classes (carotenoids, melanins, porphyrins, psittacofulvins and metal oxides). however, the pigment that generates the yellow colour of penguin feathers appears to represent a sixth, poorly characterized class of feather pigments. this pigme ... | 2013 | 23516063 |
| metabolic response to lipid infusion in fasting winter-acclimatized king penguin chicks (aptenodytes patagonicus). | during the cold austral winter, king penguin chicks are infrequently fed by their parents and thus experience severe nutritional deprivation under harsh environmental conditions. these energetic constraints lead to a range of energy sparing mechanisms balanced by the maintenance of efficient thermogenic processes. the present work investigated whether the high thermogenic capacities exhibited by winter-acclimatized king penguin chicks could be related to an increase in lipid substrate supply and ... | 2013 | 23428720 |
| the invisible cues that guide king penguin chicks home: use of magnetic and acoustic cues during orientation and short-range navigation. | king penguins (aptenodytes patagonicus) live in large and densely populated colonies, where navigation can be challenging because of the presence of many conspecifics that could obstruct locally available cues. our previous experiments demonstrated that visual cues were important but not essential for king penguin chicks' homing. the main objective of this study was to investigate the importance of non-visual cues, such as magnetic and acoustic cues, for chicks' orientation and short-range navig ... | 2013 | 23307799 |
| king penguins adjust their diving behaviour with age. | increasing experience in long-lived species is fundamental to improving breeding success and ultimately individual fitness. diving efficiency of marine animals is primarily determined by their physiological and mechanical characteristics. this efficiency may be apparent via examination of biomechanical performance (e.g. stroke frequency and amplitude, change in buoyancy or body angle, etc.), which itself may be modulated according to resource availability, particularly as a function of depth. we ... | 2012 | 23053365 |
| retinal ganglion cell topography and spatial resolving power in penguins. | penguins are a group of flightless seabirds that exhibit numerous morphological, behavioral and ecological adaptations to their amphibious lifestyle, but little is known about the topographic organization of neurons in their retinas. in this study, we used retinal wholemounts and stereological methods to estimate the total number and topographic distribution of retinal ganglion cells in addition to an anatomical estimate of spatial resolving power in two species of penguins: the little penguin, ... | 2012 | 23038153 |
| body girth as an alternative to body mass for establishing condition indexes in field studies: a validation in the king penguin. | 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 23 ... | 2012 | 22902382 |
| coping with continuous human disturbance in the wild: insights from penguin heart rate response to various stressors. | a central question for ecologists is the extent to which anthropogenic disturbances (e.g. tourism) might impact wildlife and affect the systems under study. from a research perspective, identifying the effects of human disturbance caused by research-related activities is crucial in order to understand and account for potential biases and derive appropriate conclusions from the data. | 2012 | 22784366 |
| a mechanistic understanding of ageing revealed by studying the young. | a main focus within biomedical research is to understand how adverse environmental conditions experienced during early development affects lifelong health (barker 1992). within this context, extensive research in rodent models and humans has shown that intrauterine growth retardation (iugr) caused by nutrient restriction during early development is often followed by post-natal 'catch-up' growth when access to food resources improves. however, this accelerated growth rate seems to come at a cost, ... | 2012 | 22393931 |
| sex identification of four penguin species using locus-specific pcr. | traditional methods for sex identification are not applicable to sexually monomorphic species, leading to difficulties in the management of their breeding programs. to identify sex in sexually monomorphic birds, molecular methods have been established. two established primer pairs (2550f/2718r and p8/p2) amplify the chd1 gene region from both the z and w chromosomes. here, we evaluated the use of these primers for sex identification in four sexually monomorphic penguin species: king penguins (ap ... | 2013 | 22383375 |
| projected poleward shift of king penguins' (aptenodytes patagonicus) foraging range at the crozet islands, southern indian ocean. | seabird populations of the southern ocean have been responding to climate change for the last three decades and demographic models suggest that projected warming will cause dramatic population changes over the next century. shift in species distribution is likely to be one of the major possible adaptations to changing environmental conditions. habitat models based on a unique long-term tracking dataset of king penguin (aptenodytes patagonicus) breeding on the crozet islands (southern indian ocea ... | 2012 | 22378808 |
| king penguin population on macquarie island recovers ancient dna diversity after heavy exploitation in historic times. | historically, king penguin populations on macquarie island have suffered greatly from human exploitation. two large colonies on the island were drastically reduced to a single small colony as a result of harvesting for the blubber oil industry. however, recent conservation efforts have resulted in the king penguin population expanding in numbers and range to recolonize previous as well as new sites. ancient dna methods were used to estimate past genetic diversity and combined with studies of mod ... | 2012 | 22357937 |
| selective upregulation of lipid metabolism in skeletal muscle of foraging juvenile king penguins: an integrative study. | the passage from shore to marine life of juvenile penguins represents a major energetic challenge to fuel intense and prolonged demands for thermoregulation and locomotion. some functional changes developed at this crucial step were investigated by comparing pre-fledging king penguins with sea-acclimatized (sa) juveniles (aptenodytes patagonicus). transcriptomic analysis of pectoralis muscle biopsies revealed that most genes encoding proteins involved in lipid transport or catabolism were upregu ... | 2012 | 22357259 |
| catching-up but telomere loss: half-opening the black box of growth and ageing trade-off in wild king penguin chicks. | one of the reasons for animals not to grow as fast as they potentially could is that fast growth has been shown to be associated with reduced lifespan. however, we are still lacking a clear description of the reality of growth-dependent modulation of ageing mechanisms in wild animals. using the particular growth trajectory of small king penguin chicks naturally exhibiting higher-than-normal growth rate to compensate for the winter break, we tested whether oxidative stress and telomere shortening ... | 2012 | 22117889 |
| heterothermy in growing king penguins. | a drop in body temperature allows significant energy savings in endotherms, but facultative heterothermy is usually restricted to small animals. here we report that king penguin chicks (aptenodytes patagonicus), which are able to fast for up to 5 months in winter, undergo marked seasonal heterothermy during this period of general food scarcity and slow-down of growth. they also experience short-term heterothermy below 20 °c in the lower abdomen during the intense (re)feeding period in spring, in ... | 2011 | 21847109 |
| differential muscular myosin heavy chain expression of the pectoral and pelvic girdles during early growth in the king penguin (aptenodytes patagonicus) chick. | continuous growth, associated with a steady parental food supply, is a general pattern in offspring development. so that young chicks can acquire their locomotor independence, this period is usually marked by a fast maturation of muscles, during which different myosin heavy chain (myhc) isoforms are expressed. however, parental food provisioning may fluctuate seasonally, and offspring therefore face a challenge to ensure the necessary maturation of their tissues when energy is limited. to addres ... | 2011 | 21562169 |
| measuring foraging activity in a deep-diving bird: comparing wiggles, oesophageal temperatures and beak-opening angles as proxies of feeding. | quantification of prey consumption by marine predators is key to understanding the organisation of ecosystems. this especially concerns penguins, which are major consumers of southern food webs. as direct observation of their feeding activity is not possible, several indirect methods have been developed that take advantage of miniaturised data logging technology, most commonly: detection of (i) anomalies in diving profiles (wiggles), (ii) drops in oesophageal temperature and (iii) the opening of ... | 2010 | 21037067 |
| gastrointestinal obstruction in penguin chicks. | a 7-day-old gentoo penguin (pygoscelis papua) was found dead and postmortem examination revealed impaction of the ventriculus with feathers. a review of mortality in gentoo penguin chicks from 1997 to 2007 at that institution revealed another case of feather impaction of the ventriculus in a 4-week-old chick, a sibling of the previous chick. a third case of gastrointestinal impaction occurred in a 24-day-old king penguin (aptenodytes patagonicus) with omphallitis and enteritis. in this chick, a ... | 2009 | 20235460 |
| heart rate as a predictor of energy expenditure in undisturbed fasting and incubating penguins. | heart rate (f(h)) measurement offers the possibility to monitor energy expenditure (ee) in wild animals if the ee/f(h) relationship for the species, physiological stages and activities of interest is known. this relationship has been extensively studied using oxygen consumption rate ( ) measurement in captive, repeatedly handled king penguins (aptenodytes patagonicus). unfortunately, the potential effects of stress on the observed relationships resulting from handling and confinement were not co ... | 2010 | 20008372 |
| isolation and characterization of macaroni penguin (eudyptes chrysolophus) microsatellite loci and their utility in other penguin species (spheniscidae, aves). | we report the characterization of 25 microsatellite loci isolated from the macaroni penguin (eudyptes chrysolophus). thirteen loci were arranged into four multiplex sets for future genetic studies of macaroni penguin populations. all 25 loci were tested separately in each of four other penguin species [adélie penguin (pygoscelis adeliae), chinstrap penguin (pygoscelis antarctica), gentoo penguin (pygoscelis papua) and king penguin (aptenodytes patagonicus)]. between eight and 12 loci were polymo ... | 2009 | 21564950 |
| are stress hormone levels a good proxy of foraging success? an experiment with king penguins, aptenodytes patagonicus. | in seabirds, variations in stress hormone (corticosterone; henceforth cort) levels have been shown to reflect changing marine conditions and, especially, changes in food availability. however, it remains unclear how cort levels can be mechanistically affected by these changes at the individual level. specifically, the influence of food acquisition and foraging success on cort secretion is poorly understood. in this study, we tested whether food acquisition can reduce baseline cort levels (;the f ... | 2009 | 19684217 |
| orientation in a crowded environment: can king penguin (aptenodytes patagonicus) chicks find their creches after a displacement? | for seabird species, the presence of conspecifics in a crowded breeding colony can obstruct locally available orientation cues. thus, navigation to specific locations can present a challenging problem. we investigated short-range orientation in king penguin (aptenodytes patagonicus) chicks that live in a large and densely populated colony. the two main objectives were to determine whether chicks displaced to a novel location away from the colony (i) can orient towards the colony and return to th ... | 2009 | 19112139 |
| modeling the marine resources consumed in raising a king penguin chick: an energetics approach. | accurate estimates of penguin energetics would represent an important contribution to our understanding of the trophodynamics of the southern ocean ecosystem and our ability to predict effects of environmental change on these species. we used the heart rate-rate of oxygen consumption technique to estimate rate of energy expenditure in adult king penguins raising a chick, in combination with data from the literature on changes in adult mass, chick energy requirements, and prey energy density. our ... | 2008 | 18939915 |
| are king penguin populations threatened by southern ocean warming? | | 2008 | 18579767 |
| recovery from swimming-induced hypothermia in king penguins: effects of nutritional condition. | we investigated changes in the rate of oxygen consumption (v o2) and body temperature of wild king penguins (aptenodytes patagonicus) in different nutritional conditions during recovery after exposure to cold water. over time, birds undertook an identical experiment three times, each characterized by different nutritional conditions: (1) having recently completed a foraging trip, (2) after fasting for many days, and (3) having been refed one meal after the fast. the experiments consisted of a 2- ... | 2008 | 18505379 |
| long-term fasting decreases mitochondrial avian ucp-mediated oxygen consumption in hypometabolic king penguins. | in endotherms, regulation of the degree of mitochondrial coupling affects cell metabolic efficiency. thus it may be a key contributor to minimizing metabolic rate during long periods of fasting. the aim of the present study was to investigate whether variation in mitochondrial avian uncoupling proteins (avucp), as putative regulators of mitochondrial oxidative phosphorylation, may contribute to the ability of king penguins (aptenodytes patagonicus) to withstand fasting for several weeks. after 2 ... | 2008 | 18495832 |
| king penguin population threatened by southern ocean warming. | seabirds are sensitive indicators of changes in marine ecosystems and might integrate and/or amplify the effects of climate forcing on lower levels in food chains. current knowledge on the impact of climate changes on penguins is primarily based on antarctic birds identified by using flipper bands. although flipper bands have helped to answer many questions about penguin biology, they were shown in some penguin species to have a detrimental effect. here, we present for a subantarctic species, ki ... | 2008 | 18268328 |
| behavioral and physiological significance of minimum resting metabolic rate in king penguins. | because fasting king penguins (aptenodytes patagonicus) need to conserve energy, it is possible that they exhibit particularly low metabolic rates during periods of rest. we investigated the behavioral and physiological aspects of periods of minimum metabolic rate in king penguins under different circumstances. heart rate (f(h)) measurements were recorded to estimate rate of oxygen consumption during periods of rest. furthermore, apparent respiratory sinus arrhythmia (rsa) was calculated from th ... | 2007 | 18040974 |
| to what extent might n2 limit dive performance in king penguins? | a mathematical model was used to explore if elevated levels of n2, and risk of decompression sickness (dcs), could limit dive performance (duration and depth) in king penguins (aptenodytes patagonicus). the model allowed prediction of blood and tissue (central circulation, muscle, brain and fat) n2 tensions (p(n2)) based on different cardiac outputs and blood flow distributions. estimated mixed venous p(n2) agreed with values observed during forced dives in a compression chamber used to validate ... | 2007 | 17872988 |
| pressure equilibration in the penguin middle ear. | king penguins have a venous structure in the form of a corpus cavernosum (cc) in their middle ear (me) submucosa. the cc may be viewed as a special organelle that can change me volume for pressure equilibration during deep-sea diving it is a pressure regulating organelle (pro). a similar cc and muscles also surround the external ear (ee) and may constrict it, isolating the tympanic membrane from the outside. a cc was previously found also in the me of marine diving mammals and can be expected to ... | 2008 | 17851907 |
| how accurately can we estimate energetic costs in a marine top predator, the king penguin? | king penguins (aptenodytes patagonicus) are one of the greatest consumers of marine resources. however, while their influence on the marine ecosystem is likely to be significant, only an accurate knowledge of their energy demands will indicate their true food requirements. energy consumption has been estimated for many marine species using the heart rate-rate of oxygen consumption (f(h) - v(o2)) technique, and the technique has been applied successfully to answer eco-physiological questions. how ... | 2007 | 17363231 |
| changes in body temperature in king penguins at sea: the result of fine adjustments in peripheral heat loss? | to investigate thermoregulatory adjustments at sea, body temperatures (the pectoral muscle and the brood patch) and diving behavior were monitored during a foraging trip of several days at sea in six breeding king penguins aptenodytes patagonicus. during inactive phases at sea (water temperature: 4-7 degrees c), all tissues measured were maintained at normothermic temperatures. the brood patch temperature was maintained at the same values as those measured when brooding on shore (38 degrees c). ... | 2006 | 16627689 |
| fine structural dependence of ultraviolet reflections in the king penguin beak horn. | the visual perception of many birds extends into the near-ultraviolet (uv) spectrum and ultraviolet is used by some to communicate. the beak horn of the king penguin (aptenodytes patagonicus) intensely reflects in the ultraviolet and this appears to be implicated in partner choice. in a preliminary study, we recently demonstrated that this ultraviolet reflectance has a structural basis, resulting from crystal-like photonic structures, capable of reflecting in the near-uv. the present study attem ... | 2006 | 16470837 |
| allometric estimation of metabolic rate from heart rate in penguins. | studies of the relationship between heart rate (f(h)) and rate of oxygen consumption (v(.) (o(2))), which are then used to predict field metabolic rate, frequently fail to incorporate body mass as a predictive variable. this is a potentially important omission in the study of animals whose body mass fluctuates substantially during their annual cycle. in an attempt further to improve estimates of field metabolic rate from f(h), we re-evaluated data on m(b), f(h) and v(.) (o(2)) from previous stud ... | 2005 | 16297646 |
| metabolism and thermoregulation during fasting in king penguins, aptenodytes patagonicus, in air and water. | we measured oxygen consumption rate (vo(2)) and body temperatures in 10 king penguins in air and water. vo(2) was measured during rest and at submaximal and maximal exercise before (fed) and after (fasted) an average fasting duration of 14.4 +/- 2.3 days (mean +/- 1 sd, range 10-19 days) in air and water. concurrently, we measured subcutaneous temperature and temperature of the upper (heart and liver), middle (stomach) and lower (intestine) abdomen. the mean body mass (m(b)) was 13.8 +/- 1.2 kg ... | 2005 | 15890795 |
| long-term effects of flipper bands on penguins. | changes in seabird populations, and particularly of penguins, offer a unique opportunity for investigating the impact of fisheries and climatic variations on marine resources. such investigations often require large-scale banding to identify individual birds, but the significance of the data relies on the assumption that no bias is introduced in this type of long-term monitoring. after 5 years of using an automated system of identification of king penguins implanted with electronic tags (100 adu ... | 2004 | 15801593 |
| isotopic discrimination between food and blood and feathers of captive penguins: implications for dietary studies in the wild. | using measurements of naturally occurring stable isotopes to reconstruct diets or source of feeding requires quantifying isotopic discrimination factors or the relationships between isotope ratios in food and in consumer tissues. diet-tissue discrimination factors of carbon ((13)c/(12)c, or delta (13)c) and nitrogen ((15)n/(14)n, or delta (15)n) isotopes in whole blood and feathers, representing noninvasive sampling techniques, were examined using three species of captive penguins (king aptenody ... | 2015 | 15702469 |
| heart rate and energetics of free-ranging king penguins (aptenodytes patagonicus). | the main objective of this study was to determine heart rate (fh) and the energetic costs of specific behaviours of king penguins while ashore and while foraging at sea during their breeding period. in particular, an estimate was made of the energetic cost of diving in order to determine the proportion of dives that may exceed the calculated aerobic dive limit (cadl; estimated usable o2 stores/estimated rate of oxygen consumption during diving). an implanted data logger enabled fh and diving beh ... | 2004 | 15472022 |
| effect of fasting on the vo2-fh relationship in king penguins, aptenodytes patagonicus. | king penguins (aptenodytes patagonicus) may fast for up to 30 days during their breeding period. as such extended fasting may affect the relationship between the rate of o(2) consumption (vo(2)) and heart rate (f(h)), five male king penguins were exercised at various speeds on repeated occasions during a fasting period of 24-31 days. in addition, vo(2) and f(h) were measured in the same animals during rest in cold air and water (4 degrees c). vo(2) and f(h) at rest and vo(2) during exercise decr ... | 2004 | 15178544 |
| assessing a relationship between bone microstructure and growth rate: a fluorescent labelling study in the king penguin chick (aptenodytes patagonicus). | microstructure-function relationships remain poorly understood in primary bone tissues. the relationship between bone growth rate and bone tissue type, although documented in some species by previous works, remains somewhat unclear and controversial. we assessed this relationship in a species with extreme adaptations, the king penguin (aptenodytes patagonicus). these birds have a peculiar growth, interrupted 3 months after hatching by the austral winter. before this interruption, chicks undergo ... | 2004 | 14747417 |
| spheniscins, avian beta-defensins in preserved stomach contents of the king penguin, aptenodytes patagonicus. | during the last part of egg incubation in king penguins, the male can preserve undigested food in the stomach for several weeks. this ensures survival of the newly hatched chick, in cases where the return of the foraging female from the sea is delayed. in accordance with the characterization of stress-induced bacteria, we demonstrate the occurrence of strong antimicrobial activities in preserved stomach contents. we isolated and fully characterized two isoforms of a novel 38-residue antimicrobia ... | 2003 | 14525994 |