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1.
Sci Rep ; 13(1): 592, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36631510

RESUMO

Encephalomyocarditis virus (Picornaviridae, Cardiovirus A) is the causative agent of the homonymous disease, which may induce myocarditis, encephalitis and reproductive disorders in various mammals, especially in swine. Despite the disease occurred endemically in pig farms since 1997, the recent increase of death experimented in Northern Italy prompted to furtherly investigate the evolution of the virus and the actual spread of the infection. Italian EMC viruses, collected between 2013 and 2019, showed an overall antigenic stability. The in-house ELISA Monoclonal Antibodies based, able to reveal changes in seven different antigenic sites, showed only sporadic and occasional mutations in considered samples and the subsequent phylogenetic analysis confirmed antigenic panel's remarks. All the isolates could be classified within a unique lineage, which comprise other European strains and confirm that the viruses currently circulating in Italy developed from a unique common ancestor. Despite the demonstrated stability of virus, some putative newly emerged variants were detected through antigenic profile analysis and phylogenesis. Finally, the serosurvey proved that spread of EMCV is greater than the diffusion of fatal infections would suggest, due to subclinical circulation of EMCV. It demonstrated an increase in the proportion of seropositive farms, if compared with previous data with no remarkable differences between farms with and without clinical evidence of disease.


Assuntos
Grupos de População Animal , Infecções por Cardiovirus , Doenças dos Suínos , Animais , Suínos , Vírus da Encefalomiocardite/genética , Filogenia , Infecções por Cardiovirus/epidemiologia , Infecções por Cardiovirus/veterinária , Itália/epidemiologia , Mamíferos
2.
Sci Rep ; 12(1): 2011, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35132116

RESUMO

Camera traps are a powerful tool for wildlife surveys. However, camera traps may not always detect animals passing in front. This constraint may create a substantial bias in estimating critical parameters such as the density of unmarked populations. We proposed the 'double-observer approach' with camera traps to counter the constraint, which involves setting up a paired camera trap at a station and correcting imperfect detection with a reformulated hierarchical capture-recapture model for stratified populations. We performed simulations to evaluate this approach's reliability and determine how to obtain desirable data for this approach. We then applied it to 12 mammals in Japan and Cameroon. The results showed that the model assuming a beta-binomial distribution as detection processes could correct imperfect detection as long as paired camera traps detect animals nearly independently (Correlation coefficient ≤ 0.2). Camera traps should be installed to monitor a predefined small focal area from different directions to satisfy this requirement. The field surveys showed that camera trap could miss animals by 3-40%, suggesting that current density estimation models relying on perfect detection may underestimate animal density by the same order of magnitude. We hope that our approach will be incorporated into existing density estimation models to improve their accuracy.


Assuntos
Grupos de População Animal , Animais Selvagens , Mamíferos , Fotografação/métodos , Densidade Demográfica , Animais , Camarões , Japão , Reprodutibilidade dos Testes
3.
Adv Sci (Weinh) ; 9(4): e2103388, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34894204

RESUMO

There has been increasing concern that the overuse of antibiotics in livestock farming is contributing to the burden of antimicrobial resistance in people. Farmed animals in Europe and North America, particularly pigs, provide a reservoir for livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA ST398 lineage) found in people. This study is designed to investigate the contribution of MRSA from Chinese pig farms to human infection. A collection of 483 MRSA are isolated from 55 farms and 4 hospitals in central China, a high pig farming density area. CC9 MRSA accounts for 97.2% of all farm isolates, but is not present in hospital isolates. ST398 isolates are found on farms and hospitals, but none of them formed part of the "LA-MRSA ST398 lineage" present in Europe and North America. The hospital ST398 MRSA isolate form a clade that is clearly separate from the farm ST398 isolates. Despite the presence of high levels of MRSA found on Chinese pig farms, the authors find no evidence of them spilling over to the human population. Nevertheless, the ST398 MRSA obtained from hospitals appear to be part of a widely distributed lineage in China. The new animal-adapted ST398 lineage that has emerged in China is of concern.


Assuntos
Fazendas/estatística & dados numéricos , Gado/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/epidemiologia , Doenças dos Suínos/epidemiologia , Grupos de População Animal , Animais , China/epidemiologia , Humanos , Suínos
4.
PLoS One ; 16(7): e0255025, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34324547

RESUMO

BACKGROUND: Florida's waters are a reservoir for a host of pathogens and toxins. Many of these microorganisms cause water-related diseases in people that are reportable to the Florida Department of Health. Our objective in this review was to ascertain which water-related pathogens and toxins of public health importance have been found in animal populations in Florida over the last twenty years. METHODS: Nineteen databases were searched, including PubMed and Web of Science Core Collection, using keywords and search terms for the waterborne diseases, water-related vector-borne diseases, and water-based toxins reportable to the Florida Department of Health. For inclusion, peer-reviewed journal articles were to be written in English, published between January 1, 1999 and December 31, 2019, and contain primary research findings documenting at least one of the water-related pathogens or toxins of interest in an animal population within Florida during this same time frame. RESULTS: Of over eight thousand initial search results, 65 studies were included for final analysis. The most common animal types implicated in the diseases of interest included marine mammals, fish and shellfish, wild birds, and livestock. Toxins or pathogens most often associated with these animals included toxin-producer Karenia brevis, vibriosis, Escherichia coli, and Salmonellosis. DISCUSSION/CONCLUSION: Findings from this review elucidate the water-related disease-causing pathogens and toxins which have been reported within animal populations in recent Florida history. As most of these diseases are zoonotic, our results suggest a One Health approach is necessary to support and maintain healthy water systems throughout the state of Florida for the protection of both human and animal populations.


Assuntos
Doenças Transmitidas pela Água , Grupos de População Animal , Animais , Gerenciamento de Dados , Dinoflagelados , Florida , Saúde Pública
5.
Anim Sci J ; 92(1): e13525, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33599382

RESUMO

Maintaining genetic diversity and inbreeding control are important in Japanese Black cattle production, especially in remote areas such as the islands of Okinawa Prefecture. Using a single-nucleotide polymorphism (SNP) array, we evaluated the genetic diversity and genomic inbreeding in Japanese Black cows from the islands of Okinawa Prefecture and compared them to those from other locations across Japan. Linkage disequilibrium decay was slower in cows in the islands of Okinawa Prefecture. The estimated effective population size declined over time in both populations. The genomic inbreeding coefficient (FROH ) was estimated using long stretches of consecutive homozygous SNPs (runs of homozygosity; ROH). FROH was higher in the cows on the islands of Okinawa Prefecture than on other locations. In total, 818 ROH fragments, including those containing NCAPG and PLAG1, which are major quantitative trait loci for carcass weight in Japanese Black cattle, were present at significantly higher frequencies in cows in the islands of Okinawa Prefecture. This suggests that the ROH fragments are under strong selection and that cows in the islands of Okinawa Prefecture have low genetic diversity and high genomic inbreeding relative to those at other locations. SNP arrays are useful tools for evaluating genetic diversity and genomic inbreeding in cattle.


Assuntos
Grupos de População Animal/genética , Bovinos/genética , Variação Genética , Genética Populacional/métodos , Genômica , Endogamia , Polimorfismo de Nucleotídeo Único/genética , Animais , Feminino , Homozigoto , Japão , Desequilíbrio de Ligação
6.
Biometrics ; 77(1): 352-361, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32243577

RESUMO

State-space models (SSMs) are a popular tool for modeling animal abundances. Inference difficulties for simple linear SSMs are well known, particularly in relation to simultaneous estimation of process and observation variances. Several remedies to overcome estimation problems have been studied for relatively simple SSMs, but whether these challenges and proposed remedies apply for nonlinear stage-structured SSMs, an important class of ecological models, is less well understood. Here we identify improvements for inference about nonlinear stage-structured SSMs fit with biased sequential life stage data. Theoretical analyses indicate parameter identifiability requires covariates in the state processes. Simulation studies show that plugging in externally estimated observation variances, as opposed to jointly estimating them with other parameters, reduces bias and standard error of estimates. In contrast to previous results for simple linear SSMs, strong confounding between jointly estimated process and observation variance parameters was not found in the models explored here. However, when observation variance was also estimated in the motivating case study, the resulting process variance estimates were implausibly low (near-zero). As SSMs are used in increasingly complex ways, understanding when inference can be expected to be successful, and what aids it, becomes more important. Our study illustrates (a) the need for relevant process covariates and (b) the benefits of using externally estimated observation variances for inference about nonlinear stage-structured SSMs.


Assuntos
Grupos de População Animal , Dinâmica não Linear , Animais , Modelos Teóricos , Dinâmica Populacional , Simulação de Ambiente Espacial
7.
PLoS One ; 15(1): e0227948, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31961885

RESUMO

Globally, many millions of animals are used by humans every year and much of this usage causes public concern. A new scale, devised to measure attitudes to animal use in relation to the purpose of use and species, the Animal Purpose Questionnaire (APQ), was completed by in total 483 participants, 415 British nationals and 68 participants from 39 other countries. The APQ was presented in two survey formats, alongside an established Animal Attitudes Scale (AAS). In both surveys, participants also provided demographic details to provide a context to their attitudes to animals. As might be expected, and consistent with the validity of the new scale, overall scores on the AAS and APQ were highly correlated. However, the APQ provided a more differentiated measure of attitudes to animal use across a variety of settings. The results showed that there was overall higher levels of agreement with the use of animals in medical research and basic science, less endorsement for food production and pest control, and the use of animals for other cultural practices was generally disapproved of, irrespective of species. Participants overall disagreed with the use of rabbits, monkeys, badgers, tree shrews (survey 1), chimpanzees, dogs, dolphins and parrots (survey 2), but were neutral about the use of rats, mice, pigs, octopus, chickens, zebrafish (survey 1), carp, chickens, pigs, pigeons, rabbits and rats (survey 2). Interactions between species and purpose were largely driven by the consideration of using diverse species for food production. In general, females and vegetarians expressed less agreement with the use of animals with some differences by purpose of use. Pet keeping consistently predicted reduced willingness to use animals for basic science (only). The APQ provides a new tool to unpack how public attitudes depend on the intersectionality of demographics, species and purpose of use.


Assuntos
Grupos de População Animal/psicologia , Atitude , Opinião Pública , Adolescente , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
8.
Sci Rep ; 9(1): 18720, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822695

RESUMO

A new family of paratanaoidean Tanaidacea - Paranarthrurellidae fam. nov. - is erected to accommodate two genera without family classification (Paratanaoidea incertae sedis), namely Armatognathia Kudinova-Pasternak, 1987 and Paranarthrurella Lang, 1971. Seven new species of Paranarthrurella and two of Armatognathia are described from material taken in different deep-sea areas of the Atlantic and Pacific oceans. The type species of Paranarthrurella - P. caudata (Kudinova-Pasternak, 1965) - is redescribed based on the paratype. The genus Cheliasetosatanais Larsen and Araújo-Silva, 2014 originally classified within Colletteidae is synonymised with Paranarthrurella, and Arthrura shiinoi Kudinova-Pasternak, 1973 is transferred to Armatognathia. Amended diagnoses of Armatognathia and Paranarthrurella genera are given. Choosing characters for distinguishing and defining both genera was supported by Principal Component Analysis. Designation of the new family is supported by molecular phylogenetic analysis of COI and 18S datasets. The distribution of all species currently included in the new family was visualised and their bathymetric distribution analysed.


Assuntos
Crustáceos/classificação , Filogenia , Anatomia Comparada/métodos , Distribuição Animal , Grupos de População Animal/classificação , Animais , Oceano Atlântico , Ecologia/métodos , Oceano Pacífico , Fisiologia Comparada/métodos , Análise de Componente Principal , Especificidade da Espécie
9.
Nat Commun ; 10(1): 5414, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784508

RESUMO

Coral reefs worldwide are increasingly damaged by anthropogenic stressors, necessitating novel approaches for their management. Maintaining healthy fish communities counteracts reef degradation, but degraded reefs smell and sound less attractive to settlement-stage fishes than their healthy states. Here, using a six-week field experiment, we demonstrate that playback of healthy reef sound can increase fish settlement and retention to degraded habitat. We compare fish community development on acoustically enriched coral-rubble patch reefs with acoustically unmanipulated controls. Acoustic enrichment enhances fish community development across all major trophic guilds, with a doubling in overall abundance and 50% greater species richness. If combined with active habitat restoration and effective conservation measures, rebuilding fish communities in this manner might accelerate ecosystem recovery at multiple spatial and temporal scales. Acoustic enrichment shows promise as a novel tool for the active management of degraded coral reefs.


Assuntos
Estimulação Acústica/métodos , Recifes de Corais , Ecossistema , Recuperação e Remediação Ambiental , Peixes , Migração Animal , Grupos de População Animal , Animais , Biodiversidade
10.
J Theor Biol ; 460: 13-17, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30296446

RESUMO

Matrix Population Models (MPM) are among the most widely used tools in ecology and evolution. These models consider the life cycle of an individual as composed by states to construct a matrix containing the likelihood of transitions between these states as well as sexual and/or asexual per-capita offspring contributions. When individuals are identifiable one can parametrize an MPM based on survival and fertility data and average development times for every state, but some of this information is absent or incomplete for non-cohort data, or for cohort data when individuals are not identifiable. Here we introduce a simple procedure for the parameterization of an MPM that can be used with cohort data when individuals are non-identifiable; among other aspects our procedure is a novelty in that it does not require information on stage development (or stage residence) times, which current procedures require to be estimated externally, and it is a frequent source of error. We exemplify the procedure with a laboratory cohort dataset from Eratyrus mucronatus (Reduviidae, Triatominae). We also show that even if individuals are identifiable and the duration of each stage is externally estimated with no error, our procedure is simpler to use and yields the same MPM parameter estimates.


Assuntos
Estágios do Ciclo de Vida , Modelos Biológicos , Grupos de População Animal , Animais , Humanos , Triatominae
11.
Chemosphere ; 215: 206-213, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30317091

RESUMO

Halogenated polycyclic aromatic hydrocarbons (HPAHs) were identified in biological samples from the Alberta Oil-Sands Region (AOSR) using gas chromatography coupled with high-resolution time-of-flight mass spectrometry (GC-HRTOF-MS) at a resolving power of 25,000. Knowledge of the electron ionization (EI) fragmentation behavior of individual HPAH isomers, achieved by injecting authentic standards in full-scan MS mode, was paramount in identifying a suite of HPAHs in samples from the AOSR. Confirmation of compounds in biological samples was based on the measured mass accuracy (±3 ppm) of 2 characteristic ions prominent in the EI mass spectra of each compound. Numerous compounds were detected in the high resolution total ion chromatogram in liver extracts of 4 biological species from the AOSR: river otter (Lontra Canadensis), northern pike (Esox lucius), lake whitefish (Coregonus clupeaformis) and snails (Gastropod sp.) many of which remain unidentified. Careful examination of the high-resolution accurate mass data suggests that dichloro-anthracene/phenanthrene, bromo-anthracene/phenanthrene and dibromo-fluorene were present in the biological samples. Lipid corrected concentrations of dichloro-PAHs were estimated to be 16.3 ±â€¯11.4 (n = 4) and 5.5 (n = 1) ng/g in lake whitefish and river otter, respectively. Concentrations of mono-bromo-PAHs were an order of magnitude greater in snails (170.5 ng/g) than in northern pike (12.5 ng/g) while concentrations of dibromo-PAHs were 4 times greater in snails than in northern pike. The detection of these compounds in biota implies that these compounds are bioaccumulative. The liver-based biomagnification factor of the dichloro-PAH congener in the river otter/lake whitefish feeding relationship is much smaller than 1 implying that this compound does not biomagnify.


Assuntos
Biota , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Alberta , Grupos de População Animal , Animais , Antracenos/análise , Fluorenos/análise , Halogenação , Fígado/metabolismo , Fenantrenos/análise
12.
PLoS One ; 13(9): e0202814, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30231048

RESUMO

Rainfall exerts a controlling influence on the availability and quality of vegetation and surface water for herbivores in African terrestrial ecosystems. We analyse temporal trends and variation in rainfall in the Maasai Mara ecosystem of East Africa and infer their implications for animal population and biodiversity dynamics. The data originated from 15 rain gauges in the Mara region (1965-2015) and one station in Narok Town (1913-2015), in Kenya's Narok County. This is the first comprehensive and most detailed analysis of changes in rainfall in the region of its kind. Our results do not support the current predictions of the International Panel of Climate Change (IPCC) of very likely increases of rainfall over parts of Eastern Africa. The dry season rainfall component increased during 1935-2015 but annual rainfall decreased during 1962-2015 in Narok Town. Monthly rainfall was more stable and higher in the Mara than in Narok Town, likely because the Mara lies closer to the high-precipitation areas along the shores of Lake Victoria. Predominantly deterministic and persistent inter-annual cycles and extremely stable seasonal rainfall oscillations characterize rainfall in the Mara and Narok regions. The frequency of severe droughts increased and floods intensified in the Mara but droughts became less frequent and less severe in Narok Town. The timings of extreme droughts and floods coincided with significant periodicity in rainfall oscillations, implicating strong influences of global atmospheric and oceanic circulation patterns on regional rainfall variability. These changing rainfall patterns have implications for animal population dynamics. The increase in dry season rainfall during 1935-2015 possibly counterbalanced the impacts of resource scarcity generated by the declining annual rainfall during 1965-2015 in Narok Town. However, the increasing rainfall extremes in the Mara can be expected to create conditions conducive to outbreaks of infectious animal diseases and reduced vegetation quality for herbivores, particularly when droughts and floods persist over multiple years. The more extreme wet season rainfall may also alter herbivore space use, including migration patterns.


Assuntos
Biodiversidade , Dinâmica Populacional , Grupos de População Animal , Animais , Mudança Climática , Ecossistema , Chuva
13.
Genetica ; 146(4-5): 393-402, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30046930

RESUMO

The greater amberjack (Seriola dumerili) is a commercially and recreationally important marine fish species in the southeastern United States, where it has been historically managed as two non-mixing stocks (Gulf of Mexico and Atlantic). Mark-recapture studies and analysis of mitochondrial DNA have suggested the two stocks are demographically independent; however, little is currently known about when and where spawning occurs in Gulf of Mexico amberjack, and whether stock mixture occurs on breeding grounds. The primary objective of this study was to quantify stock mixture among breeding populations of amberjack collected from the Atlantic and Gulf of Mexico. Genetic data based on 11 loci identified very low, though statistically significant differentiation among Gulf of Mexico samples (GST = 0.007, [Formula: see text] = 0.009; all P = 0.001) and between reproductive adults collected from two spawning areas (GST = 0.007, [Formula: see text] = 0.014; all P = 0.001). Naïve Bayesian mixture analysis supported a single genetic cluster [p(S|data) = 0.734] whereas trained clustering (using Atlantic and Gulf spawning fish) gave the highest support to a two-cluster model (p(S|data) = 1.0). Our results support the argument that the genetic structuring of greater amberjack is more complex than the previously assumed two, non-mixing stock model. Although our data provide evidence of limited population structure, we argue in favour of non-panmixia among reproductive fish collected from the Gulf of Mexico and Florida Keys.


Assuntos
Demografia/métodos , Perciformes/genética , Reprodução/genética , Grupos de População Animal/genética , Animais , Oceano Atlântico , Teorema de Bayes , Cruzamento , Análise por Conglomerados , DNA Mitocondrial/genética , Variação Genética/genética , Genética Populacional/métodos , Golfo do México , Repetições de Microssatélites/genética , Filogeografia/métodos , Locos de Características Quantitativas/genética
14.
Biometrics ; 74(2): 411-420, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28834536

RESUMO

Sightings of previously marked animals can extend a capture-recapture dataset without the added cost of capturing new animals for marking. Combined marking and resighting methods are therefore an attractive option in animal population studies, and there exist various likelihood-based non-spatial models, and some spatial versions fitted by Markov chain Monte Carlo sampling. As implemented to date, the focus has been on modeling sightings only, which requires that the spatial distribution of pre-marked animals is known. We develop a suite of likelihood-based spatial mark-resight models that either include the marking phase ("capture-mark-resight" models) or require a known distribution of marked animals (narrow-sense "mark-resight"). The new models sacrifice some information in the covariance structure of the counts of unmarked animals; estimation is by maximizing a pseudolikelihood with a simulation-based adjustment for overdispersion in the sightings of unmarked animals. Simulations suggest that the resulting estimates of population density have low bias and adequate confidence interval coverage under typical sampling conditions. Further work is needed to specify the conditions under which ignoring covariance results in unacceptable loss of precision, or to modify the pseudolikelihood to include that information. The methods are applied to a study of ship rats Rattus rattus using live traps and video cameras in a New Zealand forest, and to previously published data.


Assuntos
Grupos de População Animal , Animais , Conjuntos de Dados como Assunto , Funções Verossimilhança , Cadeias de Markov , Método de Monte Carlo , Nova Zelândia , Densidade Demográfica , Ratos , Análise Espacial , Gravação em Vídeo
15.
J Am Assoc Lab Anim Sci ; 56(4): 390-395, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28724488

RESUMO

Effective colony management is critical to guarantee the availability of captive NHP as subjects for biomedical research. Pigtailed macaques (Macaca nemestrina) are an important model for the study of human and nonhuman primate diseases and behavior. Johns Hopkins University hosts one of the largest captive colonies of pigtailed macaques in the United States. In this study, we used 56 single-nucleotide polymorphisms (SNP) to characterize this population of pigtailed macaques, understand their population structure, and assess the effectiveness of their colony management. The results demonstrate that the colony has maintained a high level of genetic diversity, with no loss of heterozygosity since its origin, and low levels of inbreeding and genetic subdivision.


Assuntos
Animais de Laboratório , Macaca nemestrina/genética , Polimorfismo de Nucleotídeo Único , Grupos de População Animal , Animais , Feminino , Variação Genética , Masculino
16.
J Am Assoc Lab Anim Sci ; 56(4): 396-401, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28724489

RESUMO

The rhesus macaque population at Cayo Santiago increases annually and is in urgent need of control. In-depth assessments of the colony's population genetic and pedigree structures provide a starting point for improving the colony's long-term management program. We evaluated the degree of genetic variation and coefficients of inbreeding and kinship of the Cayo Santiago colony by using pedigree and short tandem repeat (STR) data from 4738 rhesus macaques, which represent 7 extant social groups and a group of migrant males. Information on each animal's parentage, sex, birth date, and date of death or removal from the island were used to generate estimates of mean kinship, kinship value, gene value, genome uniqueness (GU), founder equivalents (fe), and founder genome equivalents (fg). Pedigree and STR analyses revealed that the social groups have not differentiated genetically from each other due to male-mediated gene flow (that is, FST estimates were in the negative range) and exhibit sufficient genetic variation, with mean estimates of allele numbers and observed and expected heterozygosity of 6.57, 0.72, and 0.70, respectively. Estimates of GU, fe, and fg show that a high effective number of founders has affected the colony's current genetic structure in a positive manner. As demographic changes occur, genetic and pedigree matrices need to be monitored consistently to ensure the health and wellbeing of the Cayo Santiago colony.


Assuntos
Macaca mulatta/genética , Grupos de População Animal , Animais , Animais Selvagens , Feminino , Variação Genética , Genética Populacional , Ilhas , Masculino , Repetições de Microssatélites , Linhagem , Porto Rico
17.
Zoolog Sci ; 33(5): 476-484, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27715415

RESUMO

Salamanders are expected to differentiate genetically among local populations due to their low dispersal ability, and are potentially susceptible to loss of genetic diversity if the population is isolated by habitat fragmentation. The salamander Hynobius tokyoensis is a lowland lentic breeder and endemic to a narrow area of central Japan. In this urban area, H. tokyoensis habitats are extensively fragmented and several populations are threatened with extinction, but information on genetic divergence and loss of genetic diversity is scarce. We performed mitochondrial (cyt b) and microsatellite (five loci) DNA analyses of 815 individuals from 46 populations in 12 regions across their entire distribution range. As a result, populations were clearly separated into northern and southern groups, and genetic differentiation among the 12 regions was also evident. Regional differentiation appears to be affected by a complex geographical history, but the genetic diversity of each population may have also been affected by recent habitat fragmentation. There were positive correlations between the mitochondrial and microsatellite DNA diversities. Some populations have lost genetic diversity in both mitochondrial and microsatellite DNAs; all such populations were at the peripheral edges of the species distribution range. Thus, even in attempts to restore genetic diversity in a small population by the transfer of outside individuals, efforts must be made to avoid genetic pollution.


Assuntos
Variação Genética , Urodelos/genética , Distribuição Animal , Grupos de População Animal , Animais , DNA Mitocondrial/genética , Ecossistema , Feminino , Repetições de Microssatélites , Filogenia , Tóquio , Urodelos/fisiologia
18.
J Proteomics ; 144: 51-62, 2016 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-27240975

RESUMO

UNLABELLED: Snake venom is a highly variable phenotypic character, and its variation and rapid evolution are important because of human health implications. Because much snake antivenom is produced from captive animals, understanding the effects of captivity on venom composition is important. Here, we have evaluated toxin profiles from six long-term (LT) captive and six recently wild-caught (RC) eastern brown snakes, Pseudonaja textilis, utilizing gel electrophoresis, HPLC-MS, and shotgun proteomics. We identified proteins belonging to the three-finger toxins, group C prothrombin activators, Kunitz-type serine protease inhibitors, and phospholipases A2, among others. Although crude venom HPLC analysis showed LT snakes to be higher in some small molecular weight toxins, presence/absence patterns showed no correlation with time in captivity. Shotgun proteomics indicated the presence of similar toxin families among individuals but with variation in protein species. Although no venom sample contained all the phospholipase A2 subunits that form the textilotoxin, all did contain both prothrombin activator subunits. This study indicates that captivity has limited effects on venom composition, that venom variation is high, and that venom composition may be correlated to geographic distribution. BIOLOGICAL SIGNIFICANCE: Through proteomic comparisons, we show that protein variation within LT and RC groups of snakes (Pseudonaja textilis) is high, thereby resulting in no discernible differences in venom composition between groups. We utilize complementary techniques to characterize the venom proteomes of 12 individual snakes from our study area, and indicate that individuals captured close to one another have more similar venom gel electrophoresis patterns than those captured at more distant locations. These data are important for understanding natural variation in and potential effects of captivity on venom composition.


Assuntos
Venenos Elapídicos/química , Elapidae , Proteômica/métodos , Estresse Fisiológico , Grupos de População Animal , Animais , Fosfolipases A2/análise , Proteômica/instrumentação , Protrombina/agonistas , Inibidores de Serino Proteinase/análise
19.
J Math Biol ; 73(1): 123-59, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26520857

RESUMO

We consider the extra clustering model which was introduced by Durand et al. (J Theor Biol 249(2):262-270, 2007) in order to describe the grouping of social animals and to test whether genetic relatedness is the main driving force behind the group formation process. Durand and François (J Math Biol 60(3):451-468, 2010) provided a first stochastic analysis of this model by deriving (amongst other things) asymptotic expansions for the mean value of the number of groups. In this paper, we will give a much finer analysis of the number of groups. More precisely, we will derive asymptotic expansions for all higher moments and give a complete characterization of the possible limit laws. In the most interesting case (neutral model), we will prove a central limit theorem with a surprising normalization. In the remaining cases, the limit law will be either a mixture of a discrete and continuous law or a discrete law. Our results show that, except of in degenerate cases, strong concentration around the mean value takes place only for the neutral model, whereas in the remaining cases there is also mass concentration away from the mean.


Assuntos
Grupos de População Animal , Modelos Biológicos , Grupos de População Animal/genética , Animais , Análise por Conglomerados , Processos Estocásticos
20.
Int J Parasitol ; 46(1): 59-66, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26475963

RESUMO

Parasites can significantly impact animal populations by changing host behaviour, reproduction and survival. Detecting and quantifying these impacts is critical for understanding disease dynamics and managing wild animal populations. However, for wild hosts infected with macroparasites, it is notoriously difficult to quantify the fatal parasite load and number of animals that have died due to disease. When ethical or logistical constraints prohibit experimental determination of these values, examination of parasite intensity and distribution data may offer an alternative solution. In this study we introduce a novel method for using intensity data to detect and quantify parasite-induced mortality in wildlife populations. We use simulations to show that this method is more reliable than previously proposed methods while providing quantitative estimates of parasite-induced mortality from empirical data that are consistent with previously published qualitative estimates. However this method, and all techniques that estimate parasite-induced mortality from intensity data alone, have several important assumptions that must be scrutinised before applying those to real-world data. Given that these assumptions are met, our method is a new exploratory tool that can help inform more rigorous studies of parasite-induced host mortality.


Assuntos
Interações Hospedeiro-Parasita , Modelos Estatísticos , Parasitos/patogenicidade , Doenças Parasitárias em Animais/mortalidade , Grupos de População Animal , Animais , Animais Selvagens/parasitologia , Comportamento Animal , Distribuição Binomial , Simulação por Computador , Dose Letal Mediana , Funções Verossimilhança , Doenças Parasitárias em Animais/parasitologia , Reprodução , Estatística como Assunto/métodos , Taxa de Sobrevida
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