Wild Reptiles Research Articles

Mortalidad de reptiles en carreteras del piedemonte de los llanos orientales colombianos

Las colisiones de vehículos con reptiles son una de las causas más importantes de pérdida de biodiversidad originadas por la construcción y funcionamiento de infraestructura vial. El objetivo del estudio fue analizar la mortalidad de reptiles en carreteras del piedemonte de los llanos orientales colombianos. Se analizaron eventos de colisión estableciendo puntos críticos, tasas de atropellamiento y su relación con el tipo de cobertura. Se realizaron recorridos entre abril y septiembre de 2015 en tres tramos de dos carreteras nacionales del departamento del Meta. Se utilizó un vehículo a velocidad media de 40 km/h y se registraron eventos de colisiones de automóviles con reptiles, documentando ubicación, identificación y cobertura asociada. Se utilizaron estimadores y pruebas de similitud para diversidad de especies. Se identificaron puntos críticos y tasas de colisión mediante mapas de calor e índices kilométricos de atropellamiento. Se registraron 204 eventos de colisión para 33 especies de reptiles con tasas de colisión entre 0,019 y 0,042 colisiones/km/día y se identificaron 30 puntos críticos de atropellamiento. Las tasas de colisión calculadas presentan una relación inversa con el tipo de cobertura ya que la presencia de bosques, matorrales y humedales está relacionada con menor cantidad de colisiones. Estos hallazgos representan una herramienta importante para implementar estrategias de prevención y mitigación de atropellamientos de fauna en la Orinoquia colombiana.

Surveillance and diagnosis of zoonotic foodborne parasites.

Foodborne parasites are a source of human parasitic infection. Zoonotic infections of humans arise from a variety of domestic and wild animals, including sheep, goats, cattle, camels, horses, pigs, boars, bears, felines, canids, amphibians, reptiles, poultry, and aquatic animals such as fishes and shrimp. Therefore, the implementation of efficient, accessible, and controllable inspection policies for livestock, fisheries, slaughterhouses, and meat processing and packaging companies is highly recommended. In addition, more attention should be paid to the education of auditors from the quality control (QC) and assurance sectors, livestock breeders, the fishery sector, and meat inspection veterinarians in developing countries with high incidence of zoonotic parasitic infections. Furthermore, both the diagnosis of zoonotic parasitic infections by inexpensive, accessible, and reliable identification methods and the organization of effective control systems with sufficient supervision of product quality are other areas to which more attention should be paid. In this review, we present some examples of successful inspection policies and recent updates on present conventional, serologic, and molecular diagnostic methods for zoonotic foodborne parasites from both human infection and animal‐derived foods.

A virulent clone of Devriesea agamarum affects endangered Lesser Antillean iguanas (Iguana delicatissima)

Infectious diseases affecting wildlife are drivers of global biodiversity loss. Here we report a bacterial threat to endangered wild reptiles. Since April 2011, a severe skin disease has affected free-ranging, endangered Lesser Antillean iguanas (Iguana delicatissima) on the French Caribbean island of Saint Barthélemy and we identified Devriesea agamarum as the causative agent. The presence of this bacterium was also demonstrated in healthy lizards (anoles) co-inhabiting the island. All isolates from the iguanas corresponded to a single AFLP genotype that until now has exclusively been associated with infections in lizard species in captivity. The clonal relatedness of the isolates and recent emergence of the disease suggest recent arrival of a virulent D. agamarum clone on the island. The presence of healthy but infected lizards suggests the presence of asymptomatic reservoir hosts. This is the first description of a bacterial disease that poses a conservation threat towards free-ranging squamates.

Ixodid tick diversity on wild mammals, birds, and reptiles in and around Etosha National Park, Namibia.

NIH GM083863 (to Wayne Getz). Ivan Horak was funded by the University of Pretoria and the National Research Foundation of South Africa.

Physiological Correlates of Multiple Parasitic Infections in Side-Blotched Lizards

We investigated the presence of ectoparasites and hemoparasites in side-blotched lizards (Uta stansburiana) across a large part of their range and measured how parasitic infection related to several key physiological indicators of health. Blood samples were collected from 132 lizards from central Arizona, southern Utah, and eastern Oregon. Hemoparasites were found in 22 individuals (3.2% prevalence in Arizona, 19.1% in Utah, and 6.3% in Oregon), and ectoparasites were found on 51 individuals (56.3% prevalence in Arizona, 56.1% in Utah, and 6.7% in Oregon), with 11 individuals infected with both. Hemoparasites and ectoparasites were found in all three states. Immunocompetence was higher in individuals infected with both hemoparasites and ectoparasites. Body condition, glucocorticoid levels, and reproductive investment were not related to infection status. Our study provides evidence that parasitic infection is associated with an active immune system in wild reptiles but may not impose other costs usually associated with parasites.

Leveraging Comparative Genomics to Identify and Functionally Characterize Genes Associated with Sperm Phenotypes in Python bivittatus (Burmese Python).

Comparative genomics approaches provide a means of leveraging functional genomics information from a highly annotated model organism's genome (such as the mouse genome) in order to make physiological inferences about the role of genes and proteins in a less characterized organism's genome (such as the Burmese python). We employed a comparative genomics approach to produce the functional annotation of Python bivittatus genes encoding proteins associated with sperm phenotypes. We identify 129 gene-phenotype relationships in the python which are implicated in 10 specific sperm phenotypes. Results obtained through our systematic analysis identified subsets of python genes exhibiting associations with gene ontology annotation terms. Functional annotation data was represented in a semantic scatter plot. Together, these newly annotated Python bivittatus genome resources provide a high resolution framework from which the biology relating to reptile spermatogenesis, fertility, and reproduction can be further investigated. Applications of our research include (1) production of genetic diagnostics for assessing fertility in domestic and wild reptiles; (2) enhanced assisted reproduction technology for endangered and captive reptiles; and (3) novel molecular targets for biotechnology-based approaches aimed at reducing fertility and reproduction of invasive reptiles. Additional enhancements to reptile genomic resources will further enhance their value.

Visualization of Assembly Intermediates and Budding Vacuoles of Singapore Grouper Iridovirus in Grouper Embryonic Cells.

Iridovirid infection is associated with the catastrophic loss in aquaculture industry and the population decline of wild amphibians and reptiles, but none of the iridovirid life cycles have been well explored. Here, we report the detailed visualization of the life cycle of Singapore grouper iridovirus (SGIV) in grouper cells by cryo-electron microscopy (cryoEM) and tomography (ET). EM imaging revealed that SGIV viral particles have an outer capsid layer, and the interaction of this layer with cellular plasma membrane initiates viral entry. Subsequent viral replication leads to formation of a viral assembly site (VAS), where membranous structures emerge as precursors to recruit capsid proteins to form an intermediate, double-shell, crescent-shaped structure, which curves to form icosahedral capsids. Knockdown of the major capsid protein eliminates the formation of viral capsids. As capsid formation progresses, electron-dense materials known to be involved in DNA encapsidation accumulate within the capsid until it is fully occupied. Besides the well-known budding mechanism through the cell periphery, we demonstrate a novel budding process in which viral particles bud into a tubular-like structure within vacuoles. This budding process may denote a new strategy used by SGIV to disseminate viral particles into neighbor cells while evading host immune response.

C-14: Comparative cryobiology of germplasms in non-traditional species

One of the greatest challenges to retaining viability of frozen gametes and reproductive tissues is understanding and overcoming species-specificities. This is important because there is significant diversity in the cryobiological properties and requirements among cell types and tissues themselves. Systematic studies can lead to successful post-thaw recovery, especially after determining (1) membrane permeability to water and cryoprotectant, (2) cryoprotectant toxicity, (3) tolerance to osmotic changes and (4) resistance to cooling and freezing temperatures. While species-dependency ultimately dictates the ability of specific cells and tissues to survive freeze–thawing, there are commonalities between taxa that allow a protocol developed for one species to provide useful information for another. This is the primary reason for performing comparative cryopreservation studies among diverse species. Our laboratory has compared cellular cryotolerance, especially in spermatozoa, in a diversity of animals – from coral to elephants – for more than 30 years. Characterizing the biophysical traits of gametes and tissues is the most efficient way to develop successful storage and recovery protocols. Such data are only available for a few laboratory, livestock and fish species, with virtually all others (wild mammals, birds, reptiles and amphibians) having gone unstudied in this arena. Nonetheless, when a rare animal unexpectedly dies, there is no time to understand the fundamentals of biophysics. In these emergencies, it is necessary to rely on experience and the best data from taxonomically-related species. Fortunately, there are some general similarities among most species, which, for example, allow adequate post-thaw viability. Regardless, there is a priority for more information on biophysical traits and freezing tolerance of distinctive biomaterials, especially for oocytes and gonadal tissues, and even for common, domesticated animals.

A novel technique to measure chronic levels of corticosterone in turtles living around a major roadway.

Conservation biology integrates multiple disciplines to expand the ability to identify threats to populations and develop mitigation for these threats. Road ecology is a branch of conservation biology that examines interactions between wildlife and roadways. Although the direct threats of road mortality and habitat fragmentation posed by roads have received much attention, a clear understanding of the indirect physiological effects of roads on wildlife is lacking. Chronic physiological stress can lower immune function, affect reproductive rates and reduce life expectancy; thus, it has the potential to induce long-lasting effects on populations. Reptiles are globally in decline, and roads are known to have negative effects on reptile populations; however, it is unknown whether individual responses to roads and traffic result in chronic stress that creates an additional threat to population viability. We successfully extracted reliable measures of corticosterone (CORT), a known, commonly used biomarker for physiological stress, from claw trimmings from painted turtles (Chrysemys picta) captured at three study sites (road-impacted site, control site and validation site). Corticosterone levels in claws were evaluated as a measure of chronic stress in turtles because CORT is deposited during growth of the claw and could provide an opportunity to examine past long-term stress levels. While male turtles had higher CORT levels on average than females, there was no difference in the level of CORT between the road-impacted and control site, nor was there a relationship between CORT and turtle body condition. In validating a novel approach for non-invasive measurement of long-term CORT levels in a keratinized tissue in wild reptiles, our study provides a new avenue for research in the field of stress physiology.

Salmonella serotypes in reptiles and humans, French Guiana

In French Guiana, a French overseas territory located in the South American northern coast, nearly 50% of Salmonella serotypes isolated from human infections belong to serotypes rarely encountered in metropolitan France. A reptilian source of contamination has been investigated. Between April and June 2011, in the area around Cayenne, 151 reptiles were collected: 38 lizards, 37 snakes, 32 turtles, 23 green iguanas and 21 caimans. Cloacal swab samples were collected and cultured. Isolated Salmonella strains were identified biochemically and serotyped. The overall carriage frequency of carriage was 23.2% (95% confidence interval: 16.7–30.4) with 23 serotyped strains. The frequency of Salmonella carriage was significantly higher for wild reptiles. Near two-thirds of the Salmonella serotypes isolated from reptiles were also isolated from patients in French Guiana. Our results highlight the risk associated with the handling and consumption of reptiles and their role in the spread of Salmonella in the environment.

Ranaviruses: Not Just for Frogs

Ranaviruses (family Iridoviridae) were discovered serendipitously during an attempt to generate frog kidney cell cultures for the propagation of Lucke herpesvirus, an oncogenic herpesvirus [1]. Unexpectedly, some cultures displayed spontaneous cytopathic effect suggestive of a viral infection. Frog virus (FV)-1 and -2 were recovered from normal kidneys, whereas FV3, isolated from a frog with renal carcinoma, became the focus of further study. A number of “intriguing” features, i.e., a highly methylated genome, ability to rapidly turn-off host macromolecular synthesis, a circularly permuted/terminally redundant genome, the use of both host- and virus-encoded RNA polymerases, and absence of polyadenylated mRNA [2], fueled early FV3 study and provided insight into a poorly characterized family of nuclear, cytoplasmic, large DNA-containing viruses. However, because ranaviruses were not pathogenic for humans or commercially important animals, were not, as originally thought, oncogenic, and did not appear to have adverse long-term impacts on wildlife, FV3 research remained a viral backwater. Recent years have seen renewed interest in ranaviruses and other iridoviruses because they have been increasingly linked to die-offs, often marked, among cultured and wild fish, amphibians, and reptiles. Here, we review ranavirus replication and gene function, then focus on their impact on cold-blooded vertebrates.

Impacts of endocrine disrupting chemicals on reproduction in wildlife.

The European Environment Agency (The Weybridge + 15 (1996-2011) report. EEA Technical report, vol 2. Copenhagen, 2012) and the United Nations Environment programme together with the World Health Organisation (State of the science of endocrine disrupting chemicals-2012. Geneva, Switzerland) both recently published major and highly authoritative reviews of endocrine disrupting chemicals in the natural environment and their effects on reproduction and health in both humans and wildlife. One surprising conclusion to emerge from these reviews was that there are relatively few well documented reports of endocrine disruption (ED) in wild mammals, mainly because much of the available evidence is correlative and does not conclusively demonstrate that the chemicals in question cause the physiological and phenotypic problems attributed to them. However, based on strong evidence from studies of wild birds, reptiles, invertebrates, and laboratory animals, it is difficult to imagine that wild mammals would be the exception. This chapter is therefore included to emphasize the point that the role of reproductive science within wildlife conservation is much broader than a narrow focus on artificial breeding technologies.

Mycoplasmosis in wildlife: a review

Mycoplasma, the smallest self-replicating life-forms, are responsible for a variety of diseases in humans, domestic animals, insects, and plants. Although the exact role of these organisms in wildlife is not available, now it is increasingly recognized that mycoplasmosis is an emerging disease in many wildlife populations. As only scattered data regarding these are available, an attempt has been made to assemble the available literature. To our knowledge, this is the first review paper regarding mycoplasmosis in wildlife. The outbreaks of mycoplasmoses such as contagious pleuropneumonia (CCPP), infectious keratoconjunctivitis (IKC), Mycoplasma ovipneumoniae and Mycoplasma capricolum subspp. capricolum infections, and contagious agalactia in wild ruminants; mycoplasmosis in raccoons; upper respiratory tract disease (URTD) and Mycoplasma crocodyli and Mycoplasma alligatoris infections in wild reptiles; and house finch conjunctivitis are showing that the prevalence of mycoplasmosis in wildlife has reached an alarming level, thus raising concerns for the conservation of many endangered species in captivity and free-ranging populations. These also emphasize the urgent need for increased surveillance and control of mycoplasma in wildlife. Some control approaches that can be followed are prevention of the spillover from domestic livestock and birds, proper quarantine of newly received animals along with mycoplasma screening, isolation of affected and suspected animals, screening of mycoplasmoses before the release of captive animals into free-ranging population, etc. At the same time, the previous dogma that mycoplasma have strict host specificity should be reconsidered in the light of new findings.

Cloacal mycobiota in wild females of Caiman latirostris (Crocodylia: Alligatoridae)

There are few reports of cloacal mycobiota on wild reptiles, and in particular, fungal presence and function in Caiman latirostris remains unknown. Our objective was to describe the fungal community present in the cloaca of wild female broad-snouted caimans during their reproductive season determine whether the number of fungi has some relationship with the female's corporeal condition. Fungi were found in 9 out of 13 cloacal samples and 14 species of fungi were isolated and identified. Three of the species isolated had the highest occurrence values, and 2 of them are pathogenic. In this case, body condition index had no relationship with fungal frequency; the fungi found in this study may have originated from soil habitat and nest substrate that are in constant contact with the cloaca of the C. latirostris females. The findings in this work support the theory that reptiles are facultative carriers of fungi or their spores.

Diversity of Pulsed-Field Gel Electrophoresis Pulsotypes, Serovars, and Antibiotic Resistance AmongSalmonellaIsolates from Wild Amphibians and Reptiles in the California Central Coast

A survey of cold-blooded vertebrates and associated surface waters in a produce-growing region on the Central California Coast was done between May and September 2011 to determine the diversity of Salmonella. Samples from 460 amphibians and reptiles and 119 water samples were collected and cultured for Salmonella. Animals sampled were frogs (n=331), lizards (n=59), newts (n=5), salamanders (n=6), snakes (n=39), and toads (n=20). Salmonella was isolated from 37 individual animals, including frogs, lizards, snakes, and toads. Snakes were the most likely to contain Salmonella, with 59% testing positive followed by 15.3% of lizards, 5% of toads, and 1.2% of frogs. Fifteen water samples (12.6%) were positive. Twenty-two different serovars were identified, and the majority of isolates were S. enterica subsp. IIIb, with subsp. I, II, and IIIa also found. The serovar isolated most frequently was S. enterica subsp. IIIb 16:z₁₀:e,n,x,z₁₅, from snakes and frogs in five different locations. S. enterica subsp. I serovar Typhimurium and the monophasic I 6,8:d:- were isolated from water, and subspecies I Duisburg and its variants were found in animals and water. Some samples contained more than one type of Salmonella. Analysis of pulsed-field gel electrophoresis pulsotypes indicated that some strains persisted in animals and water collected from the same location. Sixty-six isolates displayed antibiotic resistance, with 27 isolates resistant to more than one antibiotic, including a subspecies IIIb isolate from snake having resistance to five different antibiotics. Twenty-three isolates were resistant to more than one class of antibiotic, and six isolates were resistant to three classes. While these subspecies of IIIa and IIIb cause fewer instances of human illness, they may serve as reservoirs of antibiotic resistance, determinants in the environment, and be sources of contamination of leafy greens associated with product recalls.

Occurrence and molecular characterization of reptilian Campylobacter fetus strains isolated in Taiwan

The number of people who raise reptiles as pets has increased, but information about zoonotic Campylobacter carried by reptiles is limited. A survey of zoonotic Campylobacter species isolated from reptiles was undertaken to understand the possibility of this zoonotic bacterial pathogen causing human infection. A total of 179 fresh reptile fecal samples were collected from human-raised, pet shop and wild reptiles to survey the Campylobacter species. Basic biochemical reactions and 16S rRNA gene sequencing were used to identify the Campylobacter species. In the 179 fecal samples, 6.7% (12/179) were Campylobacter positive; all positive samples were identified as Campylobacter fetus. For the different reptile species, the prevalence of C. fetus in turtles was 9.7% (10/103), 1.7% (1/56) in lizards and 5.0% (1/20) in snakes. Based on published C. fetus subspecies-specific sequences, 9 of the C. fetus bacterial isolates were identified as C. fetus subsp. fetus by multiplex PCR. In addition, multilocus sequence typing (MLST) was used to analyze the Campylobacter epidemiology and population genetics. Most of the C. fetus strains isolated from the reptiles were genetically distinct from classical mammalian C. fetus. Only the new type of ST-43, isolated from Chelonoidis carbonaria (turtle), was closely related to mammalian strains. Strain Campy-pet-3 possesses a urease activity in this study is the first to be described in C. fetus and this strain is the only one of lizard origin. This study provides the first information of Campylobacter species distribution in reptilian feces and supports the possibility of zoonotic Campylobacter infectious diseases caused by reptiles.

First report of Amblyomma helvolum (Acari: Ixodidae) from the Taiwan stink snake, Elaphe carinata (Reptilia: Colubridae), collected in southern Taiwan

A Taiwan stink snake (Elaphe carinata) was captured in shrubbery at a fruit farm in southern Taiwan, and 3 female ticks (2 flat, one fully engorged) observed on this snake were collected and identified as Amblyomma helvolum, the first record of this host association in mainland Taiwan. The key morphological characters of female A. helvolum were photographed using a stereomicroscope. This first report of A. helvolum feeding on a reptilian host in Taiwan includes the first color illustrations of adult A. helvolum ever published. The increased international trade in wild reptiles may contribute to accidental transportation of ticks into Taiwan. The host range and vector capacity of A. helvolum for various tick-borne pathogens need to be further clarified.

Diversity of gut methanogens in herbivorous animals

The digestion of plant biomass by symbiotic microbial communities in the gut of herbivore hosts also results in the production of methane, a greenhouse gas that is released into the environment where it contributes to climate change. As methane is exclusively produced by methanogenic archaea, various research groups have devoted their efforts to investigate the population structure of symbiotic methanogens in the gut of herbivores. In this review, we summarized and compared currently available results from 16S rRNA gene clone library studies, which cover a broad range of hosts from ruminant livestock species to wild ruminants, camelids, marsupials, primates, birds and reptiles. Although gut methanogens are very diverse, they tend to be limited to specific phylogenetic groups. Overall, methanogens related to species of the genus Methanobrevibacter are the most highly represented archaea in the gut of herbivores. However, under certain conditions, archaea from more phylogenetically distant groups are the most prevalent, such as methanogens belonging to either the genus Methanosphaera, the order Methanomicrobiales or the Thermoplasmatales-Affiliated Lineage C Comparisons not only highlight the strong influence of host species and diet in the determination of the population structure of symbiotic methanogens, but also reveal other complex relationships, such as wide differences between breeds, as well as unexpected similarities between unrelated species. These observations strongly support the need for high throughput sequencing and metagenomic studies to gain further insight.

Wild Terrestrial Vertebrates Sold as Food in Open Markets in Laos

Spot checks and periodic day-long surveys of the wild mammals, birds, reptiles, and amphibians sold for food were carried out in the Lak Xao market and other markets in Laos. Birds were the predominant offering in terms of number of species, but amphibians, although represented by few species, were predominant in numbers of individuals. Mammals were a significant component of the wares, both in species and numbers of individuals. Reptiles had the lowest representation in both categories. There were slight seasonal changes in numbers of species and individuals being sold. Much of the wildlife sold in Lak Xao was brought from Nape, a village about 20 km distant and located in a different vegetation zone. Few of the birds or amphibians on offer were in high IUCN categories of risk, perhaps because the more vulnerable species had already been extirpated locally, but a considerable proportion of the mammalian and reptilian species were threatened. Some small, secretive species were not represented in the markets.

Pathogenic Parasites of Korean Wild Reptiles and Amphibians: A Study of Implications for Pathogen Transmission in a Changing Climate

Pathogenic Parasites of Korean Wild Reptiles and Amphibians: A Study of Implications for Pathogen Transmission in a Changing Climate