| cutaneous and renal geotrichosis in a giant tortoise (geochelone elephantopus). | a case of cutaneous and renal geotrichosis in a giant tortoise, geochelone elephantopus, at the zoological park of barcelona is reported. fungal hyphae and spores were seen in skin and kidney. culture of these tissues yielded geotrichum candidum. this fungus was isolated from the faeces of 5 other giant tortoises that were housed with the dead animal and from specimens of corn hydroponic culture which is part of their diet. arthrospore suspensions of the 2 strains isolated from the dead animal's ... | 1980 | 7368044 |
| a survey of the coccidian parasites of reptiles from islands of the galápagos archipelago: 1990-1994. | from 1990 through 1994, fecal samples were collected and examined for coccidian parasites from 26 giant land tortoises geochelone nigra, from 715 lava lizards tropidurus spp., from 139 land iguanas conolophus subcristatus, and from 128 marine iguanas amblyrhynchus cristatus, all of which inhabit various islands in the galápagos archipelago. none of the samples from a. cristatus or from c. subcristatus was infected with coccidia. only 1 of 26 (4%) g. nigra was infected with a single eimeria speci ... | 1996 | 8636848 |
| extreme difference in rate of mitochondrial and nuclear dna evolution in a large ectotherm, galápagos tortoises. | we sequenced approximately 4.5 kb of mtdna from 161 individuals representing 11 named taxa of giant galápagos tortoises (geochelone nigra) and about 4 kb of non-coding nuclear dna from fewer individuals of these same 11 taxa. in comparing mtdna and nucdna divergences, only silent substitutions (introns, its, mtdna control region, and synonymous substitutions in coding sequences) were considered. mtdna divergence was about 30 times greater than that for nucdna. this rate discrepancy for mtdna and ... | 2004 | 15062813 |
| sterilisation of hybrid galapagos tortoises (geochelone nigra) for island restoration. part 2: phallectomy of males under intrathecal anaesthesia with lidocaine. | lidocaine intrathecal anaesthesia was used to perform phallectomies in 15 hybrid galapagos tortoises (geochelone nigra) in a field setting as part of a conservation and ecosystem restoration project in the galapagos islands. the intrathecal injection was performed in the dorsal intercoccygeal region of the tail. once the tail and hindlimbs were relaxed and the phallus was easily exteriorised, phallectomy was performed in a routine manner. all the animals recovered well from the procedure and wer ... | 2011 | 21257586 |
| observations on the female reproductive cycle of captive giant tortoises (geochelone spp.) using ultrasound scanning. | the reproductive activities of one adult female galápagos tortoise (geochelone nigra) and three adult female aldabra tortoises (geochelone gigantea) were monitored over 2 yr using ultrasound scanning. a nonrestraining technique of tactile stimulation was used for all examinations. developing, preovulatory, and atretic ovarian follicles, as well as eggs at various stages of shell deposition, were identified and measured. in g. nigra, follicles became preovulatory at a diameter of 40-42 mm and egg ... | 1997 | 9365938 |
| documenting aggression, dominance and the impacts of visitor interaction on galápagos tortoises (chelonoidis nigra) in a zoo setting. | ensuring high levels of welfare is imperative for modern zoos, but such organisations must also engage visitors in order to successfully spread awareness and raise conservation funds. it is therefore important to understand the responses of animals to visitor interaction to optimise welfare. often, the opportunity to interact with humans may be enriching for animals, but in other contexts, this interaction may have negative welfare effects. we observed captive female galápagos giant tortoises (c ... | 2020 | 32316413 |
| role of urinary and cloacal bladders in chelonian water economy: historical and comparative perspectives. | the parisian comparative anatomist claude perrault, dissecting an indian giant tortoise in 1676, was the first to observe that the urinary bladder is of an extraordinary size in terrestrial tortoises. in 1799, the english comparative physiologist robert townson suggested that the bladder functioned as a water reservoir, as he had shown previously for frogs and toads. however, these observations went unnoticed in subsequent reports on tortoise water economy that were made by travellers and natura ... | 1998 | 9951413 |
| dna from the past informs ex situ conservation for the future: an "extinct" species of galápagos tortoise identified in captivity. | although not unusual to find captive relicts of species lost in the wild, rarely are presumed extinct species rediscovered outside of their native range. a recent study detected living descendents of an extinct galápagos tortoise species (chelonoidis elephantopus) once endemic to floreana island on the neighboring island of isabela. this finding adds to the growing cryptic diversity detected among these species in the wild. there also exists a large number of galápagos tortoises in captivity of ... | 2010 | 20084268 |
| sterilisation of hybrid galapagos tortoises (geochelone nigra) for island restoration. part 1: endoscopic oophorectomy of females under ketamine-medetomidine anaesthesia. | an endoscopic sterilisation technique for use in galapagos tortoises (geochelone nigra) was developed as part of a conservation and ecosystem restoration project. fifteen female giant galapagos tortoises were anaesthetised, intubated and positioned in dorsal recumbency. a bilateral prefemoral approach was made and the ovaries were identified using a 5 mm × 33 cm rigid telescope. in the case of endoscope-assisted oophorectomy, the ovaries were exteriorised through the same incision, the vasculatu ... | 2011 | 21257559 |
| rhabdomyosarcoma in a terrestrial tortoise (geochelone nigra) in nigeria: a case report. | a skeletal muscle tumour (rhabdomysarcoma) was diagnosed in a 4-year-old captive female terrestrial tortoise (geochelone nigra) weighing 7 kg presented at the veterinary teaching hospital, university of ibadan, ibadan, nigeria. the tumour was located at the anterior right portion of the body and ventral to the carapace. the location of the tumour prevented the tortoise from extending its head from the body. the tumour was a sessile, smooth white mass, with a soft myxomatous consistency. the ... | 2012 | 23327150 |
| evolution of ribosomal internal transcribed spacers in deuterostomia. | sequences of ribosomal internal transcribed spacers (itss) are of great importance to molecular phylogenetics and dna barcoding, but remain unstudied in some large taxa of deuterostomia. we have analyzed complete its1 and its2 sequences in 62 species from 16 deuterostomia classes, with its sequences in 24 species from 11 classes initially obtained using unannotated contigs and raw read sequences. a general tendency for both its length and gc-content increase from interior to superior deuterostom ... | 2017 | 28860009 |
| identification of genetically important individuals of the rediscovered floreana galápagos giant tortoise (chelonoidis elephantopus) provide founders for species restoration program. | species are being lost at an unprecedented rate due to human-driven environmental changes. the cases in which species declared extinct can be revived are rare. however, here we report that a remote volcano in the galápagos islands hosts many giant tortoises with high ancestry from a species previously declared as extinct: chelonoidis elephantopus or the floreana tortoise. of 150 individuals with distinctive morphology sampled from the volcano, genetic analyses revealed that 65 had c. elephantopu ... | 2017 | 28904401 |
| author correction: identification of genetically important individuals of the rediscovered floreana galápagos giant tortoise (chelonoidis elephantopus) provides founders for species restoration program. | a correction to this article has been published and is linked from the html and pdf versions of this paper. the error has been fixed in the paper. | 2018 | 29531315 |
| clinical manifestation and molecular characterization of a novel member of the nannizziopsiaceae in a pulmonary granuloma from a galapagos tortoise (chelonoidis nigra). | nannizziopsiaceae is a family of fungal organisms within the order onygenales containing two genera of important reptile pathogens, nannizziopsis and paranannizziopsis. a captive galapagos tortoise (chelonoidis nigra) from boca raton, florida, united states, was presented for a clinical history of chronic progressive lethargy and inappetence. at initial presentation, the tortoise had a moderate non-regenerative anemia, leukocytosis, whip-like heterophil projections, erythrocyte fragmentation, an ... | 2020 | 32118056 |
| total eclipse of the zoo: animal behavior during a total solar eclipse. | the infrequency of a total solar eclipse renders the event novel to those animals that experience its effects and, consequently, may induce anomalous behavioral responses. however, historical information on the responses of animals to eclipses is scant and often conflicting. in this study, we qualitatively document the responses of 17 vertebrate taxa (including mammals, birds, and reptiles) to the 2017 total solar eclipse as it passed over riverbanks zoo and garden in columbia, south carolina. i ... | 2020 | 32244374 |
| herbivorous reptiles and body mass: effects on food intake, digesta retention, digestibility and gut capacity, and a comparison with mammals. | differences in the allometric scaling between gut capacity (with body mass, bm¹·⁰⁰) and food intake (with bm⁰·⁷⁵) should theoretically result in a scaling of digesta retention time with bm⁰·²⁵ and therefore a higher digestive efficiency in larger herbivores. this concept is an important part of the so-called 'jarman-bell principle' (jbp) that explains niche differentiation along a body size gradient in terms of digestive physiology. empirical data in herbivorous mammals, however, do not confirm ... | 2011 | 20850560 |
| origin and evolutionary relationships of giant galápagos tortoises. | perhaps the most enduring debate in reptile systematics has involved the giant galápagos tortoises (geochelone nigra), whose origins and systematic relationships captivated charles darwin and remain unresolved to this day. here we report a phylogenetic reconstruction based on mitochondrial dna sequences from galápagos tortoises and geochelone from mainland south america and africa. the closest living relative to the galápagos tortoise is not among the larger-bodied tortoises of south america but ... | 1999 | 10557302 |
| a survey of blastocystis in reptiles. | a total of 28 species of reptiles were investigated for blastocystis using light microscopy and in vitro culture in biphasic egg slant medium. blastocystis species were detected in 8 (28.6%) of these 28 species in 3 tortoises (geochelone elephantopus, g. elegans and g. carbonaria), 3 snakes (boiga dendrophilla, python reticulatus and elaphe radiata), 1 crocodile (crocodylus porosus) and 1 iguana lizard (cyclura cornuta). the reptilian blastocystis appeared to be morphologically similar to b. hom ... | 1992 | 1495927 |
| giant galapagos tortoises walk without inverted pendulum mechanical-energy exchange. | animals must perform mechanical work during walking, but most conserve substantial mechanical energy via an inverted-pendulum-like mechanism of energy recovery in which fluctuations of kinetic energy (ke) and gravitational potential energy (gpe) are of similar magnitude and 180 degrees out of phase. the greatest energy recovery typically occurs at intermediate speeds. tortoises are known for their slow speeds, which we anticipated would lead to small fluctuations in ke. to have an effective exch ... | 2005 | 15802673 |
| digesta retention time in the galápagos tortoise (chelonoidis nigra). | the retention time of food in the digestive tract of animals has important implications for digestive physiology. retention time impacts digestive efficiency and among herbivores affects plant-animal interactions including herbivory and seed dispersal. poorly studied yet iconic galápagos tortoises are large-bodied generalist herbivores and ecosystem engineers which migrate seasonally. potentially variable digesta retention times due to strong seasonal and altitudinal temperature gradients may in ... | 2011 | 21871577 |
| dating cryptodiran nodes: origin and diversification of the turtle superfamily testudinoidea. | the superfamily testudinoidea is the most diverse and widely distributed clade of extant turtles. surprisingly, despite an extensive fossil record, and increasing amount of molecular data available, the temporal origin of this group is still largely unknown. to address this issue, we used a comprehensive molecular dataset to perform phylogenetic and molecular dating analyses, as well as seven fossil constraints to calibrate the ages of the nodes in the phylogeny. the molecular dataset includes t ... | 2012 | 22100825 |
| isolation and characterization of a new fungal genus and species, aphanoascella galapagosensis, from carapace keratitis of a galapagos tortoise (chelonoidis nigra microphyes). | a new fungal genus and species, aphanoascella galapagosensis, recovered from carapace keratitis in a galapagos tortoise residing in a south texas zoological collection, is characterized and described. the presence of a pale peridium composed of textura epidermoidea surrounded by scarce hülle cell-like chlamydospores, and the characteristic reticulate ascospores with an equatorial rim separates it from other genera within the onygenales. the phylogenetic tree inferred from the analysis of d1/d2 s ... | 2013 | 22852752 |
| population genomics of the endangered giant galápagos tortoise. | the giant galápagos tortoise, chelonoidis nigra, is a large-sized terrestrial chelonian of high patrimonial interest. the species recently colonized a small continental archipelago, the galápagos islands, where it has been facing novel environmental conditions and limited resource availability. to explore the genomic consequences of this ecological shift, we analyze the transcriptomic variability of five individuals of c. nigra, and compare it to similar data obtained from several continental sp ... | 2013 | 24342523 |
| is preference a predictor of enrichment efficacy in galapagos tortoises (chelonoidis nigra)? | it is widely acknowledged that environmental enrichment plays an important role in promoting the welfare of captive animals. however, a topic of debate is whether an animal's preference for an enrichment strategy is any indicator of its efficacy. in addition, relatively few studies have evaluated environmental enrichment strategies for non-mammalian species. in the present study, we compared the results of an observational evaluation of enrichment efficacy with the results of a paired-stimulus p ... | 2014 | 25065472 |
| hormonal profiles of captive galapagos tortoises (chelonoidis nigra). | monthly blood samples, daily mating observations from galapagos tortoises (chelonoidis nigra), and local rainfall and temperature were collected at the honolulu zoo as part of a fertility evaluation. testosterone concentrations were measured for males (n = 6), two of which were seen copulating and were considered sexually active. estrone sulfate and progesterone concentrations were measured for female tortoises (n = 9), two of which nested and only one had laid eggs. testosterone profiles were s ... | 2016 | 26971322 |
| carriage of antibiotic-resistant enteric bacteria varies among sites in galapagos reptiles. | increased overlap between humans and wildlife populations has increased the risk for novel disease emergence. detecting contacts with a high risk for transmission of pathogens requires the identification of dependable measures of microbial exchange. we evaluated antibiotic resistance as a molecular marker for the intensity of human-wildlife microbial connectivity in the galápagos islands. we isolated escherichia coli and salmonella enterica from the feces of land iguanas (conolophus sp.), marine ... | 2012 | 22247374 |
| mast cell tumour in a giant galapagos tortoise (geochelone nigra vicina). | a well-differentiated cutaneous mast cell tumour was diagnosed in a subadult female giant galapagos tortoise. the tumour was a pedunculated, verrucose mass located near the base of the neck. the histological features, which were diagnostic for a mast cell tumour, included abundant intracytoplasmic granules that were stained metachromatically with giemsa and toluidine blue stains. mast cell tumours are rare in reptiles, and this is the first description of a mast cell tumour in a chelonian. | 2008 | 18308330 |
| steroid levels and reproductive cycle of the galápagos tortoise, geochelone nigra, living under seminatural conditions on santa cruz island (galápagos). | the galápagos islands are home to 11 subspecies of large terrestrial tortoises (geochelone nigra). all galápagos tortoises are considered endangered and approximately 12,000 animals still exist. until now, the reproductive cycle of the galápagos tortoise has been studied only in captive animals, and no data from free-ranging tortoises have been available. during a one-year period, blood samples were collected from male and female g. nigra living under seminatural conditions on santa cruz island, ... | 1999 | 10094864 |