| squamous cell carcinoma associated with a periorbital mass in a veiled chameleon (chamaeleo calyptratus). | this report describes a squamous cell carcinoma in a 1-year-old female veiled chameleon (chamaeleo calyptratus). the lesion developed as a small (1 by 1 mm) left periocular discoloration of a scale never involving the eye. the mass was first diagnosed as an abscess, increased in size (4 by 8 by 3 mm), and recurred after two surgical resections combined with antibiotic therapy. poor nutritional condition and egg production by the chameleon complicated management of this condition. the mass was re ... | 2002 | 12236875 |
| [allergic contact urticaria caused by a chameleon. expression of sensitization to ficus benjamina]. | a 31-year-old man presented with a long history of rhinoconjunctivitis and sneezing that lasted from march to may. the man kept a chameleon (chamaeleo calyptratus) as a pet and reported about recurrent urticarial lesions, erythema, and itch after skin contact with the animal. the reactions started within a few minutes and were restricted specifically to the contact sites with the animal's claws. no comparable reactions occurred in other subjects. allergy testing confirmed allergy to hazel, alder ... | 2005 | 15657732 |
| pathogenicity of the chrysosporium anamorph of nannizziopsis vriesii for veiled chameleons (chamaeleo calyptratus). | veiled chameleons (chamaeleo calyptratus) were experimentally challenged with the fungus chrysosporium anamorph of nannizziopsis vriesii (canv). chameleons were exposed to conidia in their captive environment, or were inoculated by direct application of a conidial suspension inoculum on intact and on abraded skin. the canv induced lesions in all experimental groups and was recovered from infected animals, fulfilling koch's postulates and confirming that it may act as a primary fungal pathogen in ... | 2006 | 16805090 |
| new species of choleoeimeria (apicomplexa: eimeriidae) from the veiled chameleon, chamaeleo calyptratus (sauria: chamaeleonidae), with taxonomic revision of eimerian coccidia from chameleons. | coprological examination of 71 samples from a breeding colony of veiled chameleons, chamaeleo calyptratus duméril et duméril, 1851, revealed a presence of two species of coccidia. in 100% of the samples examined, oocysts of isospora jaracimrmani modrý et koudela, 1995 were detected. a new coccidian species, choleoeimeria hirbayah sp. n., was discovered in 32.4% of samples from the colony. its oocysts are tetrasporocystic, cylindrical, 28.3 (25-30) x 14.8 (13.5-17.5) microm, with smooth, bilayere ... | 2006 | 16898122 |
| eggs under pressure: components of water potential of chameleon eggs during incubation. | water exchange of squamate eggs is driven by the difference between the water potentials of eggs and of their nest environment. while osmotic potential is generally assumed to dominate the net water potential of eggs, resistance of the eggshell to stretching also affects egg water potential. we therefore determined osmotic potentials and pressure potentials (mechanical pressure) of eggs of the veiled chameleon chamaeleo calyptratus over the course of incubation. because embryos are diapausing ga ... | 2010 | 20105071 |
| characterization of fecal hormone patterns associated with the reproductive cycle in female veiled chameleons (chamaeleo calyptratus). | reptiles have gained popularity in the north american and european pet trade. large numbers of captive-born veiled chameleons, chamaeleo calyptratus, are produced annually but knowledge of their reproductive cycle has been limited to anecdotal observations. this study describes the hormonal changes associated with reproductive cycling in female veiled chameleons using non-invasive fecal evaluation of metabolites of the three principal ovarian steroids, estradiol (e2), testosterone (t), progester ... | 2010 | 20471385 |
| disseminated mycosis in veiled chameleons (chamaeleo calyptratus) caused by chamaeleomyces granulomatis, a new fungus related to paecilomyces viridis. | an outbreak of disseminated granulomatous disease occurred in a group of veiled chameleons (chamaeleo calyptratus) in a zoo collection. an adult female and six offspring developed large granulomas in multiple organs and were euthanized. at necropsy, roughly spherical yellow-to-white nodules 1 to 3 mm in diameter were grossly visible in the liver and other organs. histopathology revealed fungal elements that were spherical to ovoid in shape, fragments of slender to irregularly swollen hyphae, and ... | 2010 | 20660211 |
| melanophoromas and iridophoromas in reptiles. | chromatophoromas are tumours of pigment-producing cells of the skin and are rarely reported in reptiles. these tumours are subclassified on the basis of the type of pigment. the present study characterizes chromatophoromas arising in 26 reptiles, including six snakes, 19 lizards and a tortoise. these include the first reports of melanophoromas in a yellow anaconda (eunectes notaeus), pigmy rattlesnake (sistrurus spp.), southern water snake (nerodia fasciata), veiled chameleon (chamaeleo calyptra ... | 2011 | 21864845 |
| [examination on the occurence, clinical appearence and the detection of chamaeleomyces sp. in clinically diseased chameleons]. | in reptiles, over the last years the importance of diseases caused by fungal infections has steadily increased. chamaeleomyces sp. is a relatively new, but more and more relevant pathogen causing systemic mycosis in chameleons. the aim of this study therefore was to obtain information on the occurrence of these fungi in chameleons, to describe their clinical appearance and to evaluate potential diagnostic procedures. 41 chameleons belonging to six different species, and demonstrating clinical si ... | 2015 | 25876284 |
| gonadotrophin-releasing hormone agonists and other contraceptive medications in exotic companion animals. | the use of a gonadotrophin-releasing hormone agonist slow-release implant (gnrh a-sri) has become increasingly popular as an alternative for surgical contraception in many species. although these implants have proven to be very effective in some species (eg, ferrets, rats, chicken, psittacines, and iguanas), they have been found less effective in other species (eg, male guinea pigs and rabbits, veiled chameleons, slider turtles, and leopard geckos). this review provides an overview of the availa ... | 2018 | 29655478 |
| gular pouch diversity in the chamaeleonidae. | numerous chameleon species possess an out-pocketing of the trachea known as the gular pouch. after surveying more than 250 specimens, representing nine genera and 44 species, we describe two different morphs of the gular pouch. species of the genera bradypodion and chamaeleo, as well as trioceros goetzei, all possess a single gular pouch (morph one) formed from ventral expansion of soft tissue where the larynx and trachea meet. furcifer oustaleti and furcifer verrucosus possess from one to four ... | 2020 | 31680478 |
| ultrasonographic appearance of the coelomic cavity organs in healthy veiled chameleons (chamaeleo calyptratus) and panther chameleons (furcifer pardalis). | veiled chameleons (chamaeleo calyptratus) and panther chameleons (furcifer pardalis) are the most popular chameleons over the world, and consequently, two of the most frequent species presenting to veterinary practices. however, published studies on normal ultrasonographic anatomy for these lizards are currently lacking. the objectives of this prospective anatomic study were to develop an ultrasound protocol for evaluation of the coelomic cavity in these species and describe the normal ultrasono ... | 2020 | 31794122 |
| the atlas-axis complex in chamaeleonids (squamata: chamaeleonidae), with description of a new anatomical structure of the skull. | the comparative vertebral morphology of different chamaeleonid genera has been generally neglected and some aspects such as the comparative anatomy of the neck region remain poorly known. the atlas and axis of all chamaeleonid genera (brookesia, rieppeleon, archaius, rhampholeon, nadzikambia, bradypodion, chamaeleo, calumma, furcifer, kinyongia, and trioceros) are studied here. considerable morphological differences are revealed. additionally, some taxa exhibit sexual dimorphism in the atlas and ... | 2014 | 24482363 |
| the transcriptome of the veiled chameleon (chamaeleo calyptratus): a resource for studying the evolution and development of vertebrates. | the veiled chameleon (chamaeleo calyptratus) is an emerging model system for studying functional morphology and evolutionary developmental biology (evo-devo). chameleons possess body plans that are highly adapted to an arboreal life style, featuring laterally compressed bodies, split hands/ft for grasping, a projectile tongue, turreted independently moving eyes, and a prehensile tail. despite being one of the most phenotypically divergent clades of tetrapods, genomic resources for chameleons are ... | 2019 | 30839129 |
| developmental plasticity in reptiles: insights into thermal and maternal effects on chameleon phenotypes. | embryonic environments affect a range of phenotypic traits including sex and reproductive success. i determined (1) how the interaction between incubation temperature and egg size affects sex allocation of chamaeleo calyptratus and (2) how incubation temperature and maternal parent (clutch) affect water uptake by eggs and body size, growth, and climbing speed of hatchlings and juveniles. eggs from five clutches were exposed to five temperature treatments with clutches replicated within and among ... | 2018 | 29682910 |
| disseminated systemic mycosis in veiled chameleons (chamaeleo calyptratus) caused by chamaeleomyces granulomatis. | the aim of the examination was to gain knowledge on the incidence of chamaeleomyces granulomatis mycosis in veiled chameleons (chamaeleo calyptratus), a disease which has recently been described as a single outbreak in a zoo collection. during a time period of 26 months (september 2009-november 2011) 18 veiled chameleons presented at the clinic for various reasons were examined for the presence of c. granulomatis. swabs were taken from tongue and skin lesions of live chameleons and from internal ... | 2012 | 22857978 |
| characterization of metarhizium viride mycosis in veiled chameleons (chamaeleo calyptratus), panther chameleons (furcifer pardalis), and inland bearded dragons (pogona vitticeps). | metarhizium viride has been associated with fatal systemic mycoses in chameleons, but subsequent data on mycoses caused by this fungus in reptiles are lacking. the aim of this investigation was therefore to obtain information on the presence of m. viride in reptiles kept as pets in captivity and its association with clinical signs and pathological findings as well as improvement of diagnostic procedures. beside 18s ribosomal dna (rdna) (small subunit [ssu]) and internal transcribed spacer region ... | 2017 | 28003420 |
| fungal dermatitis, glossitis and disseminated visceral mycosis caused by different metarhizium granulomatis genotypes in veiled chameleons (chamaeleo calyptratus) and first isolation in healthy lizards. | metarhizium (m.) granulomatis (formerly chamaeleomyces granulomatis) invariably causes fatal fungal glossitis and systemic mycosis in veiled chameleons (chamaeleo calyptratus). isolation of m. granulomatis in other lizards thus far has not been described. the aim of this study therefore was to obtain information on the presence of m. granulomatis in reptiles kept as pets, and to examine whether there was an association between specific genotypes and clinical/pathological outcomes. besides 18s ri ... | 2017 | 28757044 |
| the veiled chameleon (chamaeleo calyptratus duméril and duméril 1851): a model for studying reptile body plan development and evolution. | vertebrate model organisms have facilitated the discovery and exploration of morphogenetic events and developmental pathways that underpin normal and pathological embryological events. in contrast to amniotes such as mus musculus (mammalia) and gallus gallus (aves), our understanding of early patterning and developmental events in reptiles (particularly nonavians) remains weak. squamate reptiles (lizards, snakes, and amphisbaenians) comprise approximately one-third of all living amniotes. but st ... | 2015 | 26310903 |
| biodynamics of climbing: effects of substrate orientation on the locomotion of a highly arboreal lizard (chamaeleo calyptratus). | arboreal substrates differ not only in diameter, but also in continuity and orientation. to gain more insight into the dynamics of small-branch locomotion in tetrapods we studied the veiled chameleon walking on inclined and declined perches of up to 60 deg slope. we found that forelimbs and hindlimbs contribute equally to the body's progression along inclines and declines. the higher-positioned limb's vertical impulses decreased with slope. and although vertical impulses in the lower-positioned ... | 2012 | 23264492 |
| Fibrosing myopathy of the temporal muscles causing lockjaw in a veiled chameleon (Chamaeleo calyptratus). | | 2011 | 21949086 |
| dry matter and calcium digestibility in captive veiled chameleons (chamaeleo calyptratus). | although metabolic bone disease (mbd) is a very common disease in reptiles kept as pets, empirical data on the calcium (ca) metabolism of reptiles are still scarce. we used the opportunity of a large-scale experimental study on growth and clinical manifestations of mbd in captive veiled chameleons (chamaeleo calyptratus) to measure the apparent dry matter (dm) and ca digestibility in 19 animals (6-49 g), receiving locust nymphs (locusta migratoria) of two size classes (0.05 and 0.5 g) with or wi ... | 2011 | 21635572 |
| noninvasive analysis of fecal reproductive hormone metabolites in female veiled chameleons (chamaeleo calyptratus) by enzyme immunoassay. | the noninvasive technique of gonadal steroid metabolite measurement in feces for evaluation of reproductive activity has proven an effective and important tool for population management in various captive species, but has not yet been validated and used in reptile species. in this study, enzyme immunoassays (eias) were validated for the analysis of fecal samples from female veiled chameleons (chamaeleo calyptratus) for estrogen (e2), testosterone (t), and progesterone (p) and their metabolites. ... | 2011 | 21319212 |
| nutritional metabolic bone disease in juvenile veiled chameleons (chamaeleo calyptratus) and its prevention. | nutritional metabolic bone disease (nmbd) is one of the most frequently observed pathological conditions in herpetoculture. to develop guidelines for nmbd prevention in growing veiled chameleons (chamaeleo calyptratus), 56 hatchlings were divided into 6 groups [group uv, with uvb exposure; group no: no supplements; group caauv: with calcium (ca), vitamin a, uvb; group caa: with ca, vitamin a; group caaduv: with ca, vitamin a, cholecalciferol, uvb; and group caad, with ca, vitamin a, cholecalcife ... | 2010 | 20881081 |
| fecal hormone patterns during non-ovulatory reproductive cycles in female veiled chameleons (chamaeleo calyptratus). | reproductive failure, in particular preovulatory stasis, is a common problem in captive female reptiles. for a better understanding of its pathogenesis, the patterns of fecal estradiol (e2), testosterone (t), progesterone (p) and their metabolites of 21 anovulatory female veiled chameleons, chamaeleo calyptratus, were compared with those of 25 animals which ovulated during at least one cycle over the study period. regular, cyclical hormone patterns, consisting of e2 peaks followed by simultaneou ... | 2010 | 20603125 |
| effects of incubation temperature on growth and performance of the veiled chameleon (chamaeleo calyptratus). | i evaluated the effect of incubation temperature on phenotypes of the veiled chameleon, chamaeleo calyptratus. i chose this species for study because its large clutch size (30-40 eggs or more) allows replication within clutches both within and among experimental treatments. the major research objectives were (1) to assess the effect of constant low, moderate, and high temperatures on embryonic development, (2) to determine whether the best incubation temperature for embryonic development also pr ... | 2008 | 18512704 |
| effects of temperature on embryonic development of the veiled chameleon, chamaeleo calyptratus. | temperature dependence of development of the chameleon, chamaeleo calyptratus, was assessed from observations on eggs incubated at 25, 28 and 30 degrees c. overall, differentiation, growth in mass, and growth of the yolk sac and chorioallantois were the slowest at 25 degrees c but did not differ between 28 and 30 degrees c. the relative area of the yolk sac (ys), chorioallantoic membrane (cam), and their precursor, the area opaca vasculosa (av) was used to characterize developmental phases. duri ... | 2007 | 17890118 |
| [ganglioneuroblastoma in yemenite chameleon (chamaeleo calyptratus): the first recorded case of a tumor of neuroectodermal histogenesis in reptiles]. | nerve tissue tumors are rarely encountered in reptiles and mainly represented by some documented cases of malignant peripheral nerve sheath tumor (mpnst). the paper is the first to describe a tumor mimicking mpnst by some ultrastructural features of tumor cells; however, significantly differing in the combination of immunohistochemical characteristics. based on the data of electronic microscopy, immunohistochemistry, cytology, and histology, the tumor was classified as ganglioneuroblastoma. sinc ... | 2006 | 16986500 |
| physiological and morphological characteristics of the rhythmic contractions of the amnion in veiled chameleon (chamaeleo calyptratus) embryogenesis. | a morpho-functional study of the veiled chameleon (chamaeleo calyptratus) amnion was performed as part of a general comparative study of amnion rhythmic contractions (arc) in reptile and bird embryogenesis. eggs incubated at 27.5 degrees c were used at different developmental stages from day 80 (d80) to d184 for the recording of arc using a force transducer. slow arc, about 1 min in duration, were revealed from d88 (stage 31) to the near-hatching stages (incubation time was 183-198 days). the fr ... | 2005 | 15664309 |
| effects of temperature and moisture on embryonic diapause of the veiled chameleon (chamaeleo calyptratus). | the development of lizard embryos is typically initiated at fertilization and continues until birth or hatching. in contrast, embryonic development of some chameleons is arrested at the gastrula stage, and embryos remain at this stage for months after the eggs are laid. our research tested the hypothesis that increased temperature, moisture, or both, are associated with the resumption of development by diapausing embryos of chamaeleo calyptratus, the veiled chameleon. after 40 days of incubation ... | 2004 | 15286942 |
| in vivo muscle activity in the hindlimb of the arboreal lizard, chamaeleo calyptratus: general patterns and the effects of incline. | arboreal animals often move on surfaces with variable and steep inclines, but the changes in hindlimb muscle activity in response to incline are poorly understood. thus, we studied the hindlimb muscle activity in the arboreal specialist, chamaeleo calyptratus, moving up and down 45 degrees inclines and on a horizontal surface. we quantified electromyograms (emgs) from nine hindlimb muscles, and correlated emgs with three-dimensional hindlimb kinematics. kinematics changed little with incline, bu ... | 2004 | 14668309 |
| locomotion of lizards on inclines and perches: hindlimb kinematics of an arboreal specialist and a terrestrial generalist. | arboreal animals, especially lizards, often traverse three-dimensional networks of narrow perches with variable and steep inclines, but the effects of both incline and narrow surfaces on the locomotor movement and function of limbs are poorly understood. thus, we quantified the three-dimensional hindlimb kinematics of a specialized arboreal lizard, chamaeleo calyptratus, moving horizontally, and up and down a 30 degrees incline on a narrow (2.4 cm) perch and a flat surface. we compared the flat- ... | 2004 | 14668308 |
| displaced retinal ganglion cells project to the accessory optic system in the chameleon ( chamaeleo calyptratus). | retinal ganglion cells were successfully labelled in the chameleon by retrograde axonal transport of dextran amines that were applied to the nucleus of the basal optic root (nbor) in an in vitro preparation. labelled ganglion cells were restricted to the contralateral eye. many cells were completely stained including their dendritic trees. with few exceptions, all cells had displaced somata that were located at the inner margin of the inner nuclear layer. the labelled ganglion cells had two to s ... | 2002 | 12070745 |
| little if any role of male gonadal androgens in ontogeny of sexual dimorphism in body size and cranial casque in chameleons. | proximate control of the development of sexual dimorphism is still hotly debated in reptiles. in some squamates, many male-typical exaggerated traits including body size were assumed to be controlled by masculinization by male gonadal androgens. we performed a manipulative experiment to test the importance of this mechanism in the development of pronounced sexual differences in body size and size of head casque in the chameleon chamaeleo calyptratus. castrated males attained male-typical body si ... | 2020 | 32060387 |
| polarized sonic hedgehog protein localization and a shift in the expression of region-specific molecules is associated with the secondary palate development in the veiled chameleon. | secondary palate development is characterized by the formation of two palatal shelves on the maxillary prominences, which fuse in the midline in mammalian embryos. however, in reptilian species, such as turtles, crocodilians, and lizards, the palatal shelves of the secondary palate develop to a variable extent and morphology. while in most squamates, the palate is widely open, crocodilians develop a fully closed secondary palate. here, we analyzed developmental processes that underlie secondary ... | 2020 | 32850780 |
| the role of hyoid muscles in biotremor production in chamaeleo calyptratus. | the production of biotremors has been described in veiled chameleons (chamaeleo calyptratus), but the mechanism by which they are produced is unknown. we gathered muscle activation data via electromyography (emg) with simultaneous recordings of biotremors using an accelerometer to test for the role of hyoid muscles in their production. we recorded mean biotremor frequency of 150.87 hz for females and 136.01 hz for males. the durations of activity and the latencies to onset and offset for the m. ... | 2020 | 33071217 |
| filling in the phylogenetic gaps: induction, migration, and differentiation of neural crest cells in a squamate reptile, the veiled chameleon (chamaeleo calyptratus). | neural crest cells comprise a migratory progenitor cell population that differentiate into cell types such as neurons and glia of the peripheral nervous system, pigment cells, hormone secreting cells in glands, and skeletal and connective tissue in the head, thus making important contributions to most tissues and organs throughout the vertebrate body. the evolutionary appearance of neural crest cells is considered synonymous with the origin of vertebrates and their subsequent diversification and ... | 2019 | 30980777 |
| karyological characterization of the common chameleon (chamaeleo chamaeleon) provides insights on the evolution and diversification of sex chromosomes in chamaeleonidae. | chameleons display high karyological diversity in chromosome number (from 2n = 20 to 62), morphology, heterochromatin distribution and location of specific chromosomal markers, making them unique study models in evolutionary cytogenetics. however, most available cytogenetic data are limited to the description of the chromosome number and morphology. concerning sex chromosomes, our knowledge is limited to zz/zw and z1z1z2z2/z1z2w systems in the genus furcifer and the isolation of sex-linked, male ... | 2020 | 32291142 |
| dynamic sex chromosomes in old world chameleons (squamata: chamaeleonidae). | much of our current state of knowledge concerning sex chromosome evolution is based on a handful of 'exceptional' taxa with heteromorphic sex chromosomes. however, classifying the sex chromosome systems of additional species lacking easily identifiable, heteromorphic sex chromosomes is indispensable if we wish to fully understand the genesis, degeneration and turnover of vertebrate sex chromosomes. squamate reptiles (lizards and snakes) are a potential model clade for studying sex chromosome evo ... | 2018 | 29345015 |
| bi-modal strategy of gastrulation in reptiles. | amniote gastrulation is often described with respect to human, mouse and chick development by the presence of the primitive streak, a posterior-to-anterior midline morphological cell ingression feature that has come to define amniote gastrulation. how this midline, ingression-based strategy of gastrulation evolved from the ancestral blastopore, a circumferential involution event in anamniotes, is unknown. however, within the amniote clade there exists a more diverse range of gastrulation strateg ... | 2015 | 26088476 |
| lifting the veil on reptile embryology: the veiled chameleon (chamaeleo calyptratus) as a model system to study reptilian development. | living amniotes comprise three major phylogenetic lineages: mammals, birds, and non-avian reptiles. mouse and avian embryos continue to be the primary species used in experimental settings to further our knowledge and understanding of the genetics and embryology of amniotes. in comparison, non-avian reptiles, which constitute up to 40% of all living amniotes, have played a comparatively minor role. studies of non-avian reptiles are, however, paramount for providing insights into the evolutionary ... | 2017 | 28809028 |
| comparative musculoskeletal anatomy of chameleon limbs, with implications for the evolution of arboreal locomotion in lizards and for teratology. | chameleon species have recently been adopted as models for evo-devo and macroevolutionary processes. however, most anatomical and developmental studies of chameleons focus on the skeleton, and information about their soft tissues is scarce. here, we provide a detailed morphological description based on contrast enhanced micro-ct scans and dissections of the adult phenotype of all the forelimb and hindlimb muscles of the veiled chameleon (chamaeleo calyptratus) and compare these muscles with thos ... | 2017 | 28517034 |
| cornea and its adaptation to environment and accommodation function in veiled chameleon (chamaeleo calyptratus): ultrastructure and 3d transmission electron tomography. | we investigate the ultrastructural features and 3d electron tomography of chameleon (chamaeleon calyptratus) which is a native of desert environments of saudi arabia. the corneas of the chameleon were fixed in 2.5% glutaraldehyde containing cuprolinic blue in sodium acetate buffer for electron microscopy and tomography, and observed under a jeol 1400 transmission electron microscope. the thin cornea (21.92 μm) contained 28-30 collagen fibril lamellae. the middle stromal lamellae (from 13 to 19) ... | 2017 | 28150361 |
| social costs enforce honesty of a dynamic signal of motivation. | understanding the processes that promote signal reliability may provide important insights into the evolution of diverse signalling strategies among species. the signals that animals use to communicate must comprise mechanisms that prohibit or punish dishonesty, and social costs of dishonesty have been demonstrated for several fixed morphological signals (e.g. colour badges of birds and wasps). the costs maintaining the honesty of dynamic signals, which are more flexible and potentially cheatabl ... | 2016 | 27798310 |
| hand/foot splitting and the 're-evolution' of mesopodial skeletal elements during the evolution and radiation of chameleons. | one of the most distinctive traits found within chamaeleonidae is their split/cleft autopodia and the simplified and divergent morphology of the mesopodial skeleton. these anatomical characteristics have facilitated the adaptive radiation of chameleons to arboreal niches. to better understand the homology of chameleon carpal and tarsal elements, the process of syndactyly, cleft formation, and how modification of the mesopodial skeleton has played a role in the evolution and diversification of ch ... | 2015 | 26382964 |
| interactions between biliverdin, oxidative damage, and spleen morphology after simulated aggressive encounters in veiled chameleons. | stressors frequently increase oxidative damage--unless organisms simultaneously mount effective antioxidant responses. one putative mitigative mechanism is the use of biliverdin, an antioxidant produced in the spleen during erythrocyte degradation. we hypothesized that both wild and captive-bred male veiled chameleons (chamaeleo calyptratus), which are highly aggressive to conspecifics, would respond to agonistic displays with increased levels of oxidative damage, but that increased levels of bi ... | 2015 | 26368930 |
| captive care, raising, and breeding of the veiled chameleon (chamaeleo calyptratus). | squamate reptiles comprise approximately one-third of all living amniotes. in most of these species, it is difficult to study gastrulation and neurulation because the embryos are at a late stage of development at the time of oviposition. this is not the case, however, in veiled chameleons (chamaeleo calyptratus), which are increasingly being used as a model organism to study these and other developmental and evolutionary phenomena. originating from the arabian peninsula, veiled chameleons are ar ... | 2015 | 26310902 |
| assessment of the reproductive status of female veiled chameleons (chamaeleo calyptratus) using hormonal, behavioural and physical traits. | egg binding is a common reproductive disorder in captive female reptiles leading to premature loss of breeding potential, or in severe cases death. it can result from failure to ovulate (and reabsorb) follicles; follicular stasis, or failure to lay eggs; dystocia. reproductive status of female veiled chameleons (chamaeleo calyptratus) in a research colony was assessed using enzyme immunoassay (eia) of fecal reproductive hormones (estradiol; e2, progesterone; p, and testosterone; t) and their met ... | 2016 | 25393418 |
| subdigital setae of chameleon feet: friction-enhancing microstructures for a wide range of substrate roughness. | hairy adhesive systems of microscopic setae with triangular flattened tips have evolved convergently in spiders, insects and arboreal lizards. the ventral sides of the feet and tails in chameleons are also covered with setae. however, chameleon setae feature strongly elongated narrow spatulae or fibrous tips. the friction enhancing function of these microstructures has so far only been demonstrated in contact with glass spheres. in the present study, the frictional properties of subdigital setae ... | 2014 | 24970387 |
| influence of feeding and uvb exposition on the absorption mechanisms of calcium in the gastrointestinal tract of veiled chameleons (chamaeleo calyptratus). | the purpose of this study was to investigate the influence of feeding and uvb exposition on the occurrence and distribution patterns of vitamin d receptors (vdr) and calbindin d28k (cb-d28k) in the gastrointestinal tract of veiled chameleons. thus, 56 veiled chameleon hatchlings were divided into six treatment groups: uv (with uvb exposure); no (no supplements, no uvb exposure); caauv (with calcium (ca), vitamin a supplementation, uvb exposure); caa (with ca, vitamin a supplementation); caaduv ( ... | 2014 | 24848550 |
| the scaling of tongue projection in the veiled chameleon, chamaeleo calyptratus. | within a year of hatching, chameleons can grow by up to two orders of magnitude in body mass. rapid growth of the feeding mechanism means that bones, muscles, and movements change as chameleons grow while needing to maintain function. a previous morphological study showed that the musculoskeletal components of the feeding apparatus grow with negative allometry relative to snout-vent length (svl) in chameleons. here, we investigate the scaling of prey capture kinematics and muscle physiological c ... | 2014 | 24703241 |
| the effect of carotenoid supplementation on immune system development in juvenile male veiled chameleons (chamaeleo calyptratus). | nutrient availability, assimilation, and allocation can have important and lasting effects on the immune system development of growing animals. though carotenoid pigments have immunostimulatory properties in many animals, relatively little is known regarding how they influence the immune system during development. moreover, studies linking carotenoids to health at any life stage have largely been restricted to birds and mammals. we investigated the effects of carotenoid supplementation on multip ... | 2014 | 24655326 |
| chameleons communicate with complex colour changes during contests: different body regions convey different information. | many animals display static coloration (e.g. of feathers or fur) that can serve as a reliable sexual or social signal, but the communication function of rapidly changing colours (as in chameleons and cephalopods) is poorly understood. we used recently developed photographic and mathematical modelling tools to examine how rapid colour changes of veiled chameleons chamaeleo calyptratus predict aggressive behaviour during male-male competitions. males that achieved brighter stripe coloration were m ... | 2013 | 24335271 |
| odontogenesis in the veiled chameleon (chamaeleo calyptratus). | replacement teeth in reptiles and mammals develop from a successional dental lamina. in monophyodont (single generation) species such as the mouse, no successional lamina develops. we have selected a reptilian monophyodont species - the veiled chameleon (chamaeleo calyptratus) - to investigate whether this is a common characteristic of species that do not have replacement teeth. furthermore, we focus on the sequence of tooth initiation along the jaw, and tooth attachment to the bones. | 2013 | 23200300 |