Artículos de revistas: "Intra-species conservation"

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Clarke, Declan, Anurag Sethi, Shantao Li, Sushant Kumar, Richard W. F. Chang, Jieming Chen y Mark Gerstein. "Identifying Allosteric Hotspots with Dynamics: Application to Inter- and Intra-species Conservation". Structure 24, n.º 5 (mayo de 2016): 826–37. http://dx.doi.org/10.1016/j.str.2016.03.008.

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CRONIN, MATTHEW A. "A Proposal to Eliminate Redundant Terminology for Intra-Species Groups". Wildlife Society Bulletin 34, n.º 1 (marzo de 2006): 237–41. http://dx.doi.org/10.2193/0091-7648(2006)34[237:aptert]2.0.co;2.

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Huang, Hongwen. "671 Genetic Diversity in Actinidia and Conservation Strategy". HortScience 35, n.º 3 (junio de 2000): 514C—514. http://dx.doi.org/10.21273/hortsci.35.3.514c.

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The genus Actinidia contains more than 66 species and 118 taxa. The best-known species is A. deliciosa C.F. Liang et A.R. Ferguson, the commercially developed kiwifruit. The natural range of Actinidia is remarkably wide, extending from the tropics (latitude 0°0′) to cold temperate regions (500°N). However, the original distribution of most taxa of Actinidia is centered around the mountains and hills of south-central and southeast China, with the QinLing mountain as its northern boundary and the HengDuan mountain as its western boundary. Sixty-two species, 114 taxa have been found in China. Genetic variation ranging from morphological traits to DNA is discussed in here. 1) Morphological variation (mainly horticulturally important traits): fruit size varies from 2 to 100 g, fruit skin color ranges from brown to green to white to purple, fruit surface from setose to villose, and flesh color from green to purple. 2) Nutritional value and flavor: vitamin C content varies from 10 mg/100 g to 1000 mg/100 g fresh fruit, soluble solids ranges from 2% to 22%, and flavor includes variation form bitter and astringent to desirable sour-sweet. 3) Gender variation includes six phenotype/genotypes of female, inconstant female, male, fruiting male, neuter and hermaphrodite. 4) Ploidy variation is consist of 2x, 4x, 6x, 8x in both intra- and inter-taxa variation. 5) Isozyme genetic variation: high polymorphisms were detected in commercial cultivated species and 28 wild species. 6) Genetic diversity was evaluated by RAPD, SSR, PCR-RFLP of mtDNA and cpDNA, a high level of genetic diversity was found in both inter-taxa and intra-taxa. Conservation strategy for diverse genetic resources of Actinidia in China is also discussed.

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Heneidy, Selim Z., Marwa W. A. Halmy, Soliman M. Toto, Sania K. Hamouda, Amal M. Fakhry, Laila M. Bidak, Ebrahem M. Eid y Yassin M. Al-Sodany. "Pattern of Urban Flora in Intra-City Railway Habitats (Alexandria, Egypt): A Conservation Perspective". Biology 10, n.º 8 (22 de julio de 2021): 698. http://dx.doi.org/10.3390/biology10080698.

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Intra-city railway areas are deemed large greenspaces and are believed to be key in enhancing the diversity and dynamics of urban flora. In the current study, the floristic composition and diversity along intra-city railway and tram tracks in Alexandria were surveyed. The floristic composition of the plant communities in relation to environmental factors, ecological indicators, and level of human impact was analyzed using multivariate analysis (two-way indicator species analysis (TWINSPAN) for classification and detrended correspondence analysis (DECORANA) for ordination. The multivariate ordination techniques (CCA) revealed differences in the environmental factors and climatic factors influencing the floristic composition of the railway and tram track habitats. Tram tracks suffered higher human impact while maintaining higher vitality and cover compared to train tracks. Species recorded were mainly therophytes, followed by phanerophytes and hemicryptophytes dominated by native species; however, invasive species’ contribution was higher compared to surrounding regions. The number of invasive species was greater in railway areas compared to tram track areas (19 and 15, respectively). The occurrence of two endemic species (Sinapis allionii and Sonchus macrocarpus) with limited national distribution highlights the importance of these habitats as valuable refuge areas for rare and endangered species worthy of conservation action.

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Larson, Eric R., Magalie Castelin, Bronwyn W. Williams, Julian D. Olden y Cathryn L. Abbott. "Phylogenetic species delimitation for crayfishes of the genusPacifastacus". PeerJ 4 (18 de abril de 2016): e1915. http://dx.doi.org/10.7717/peerj.1915.

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Molecular genetic approaches are playing an increasing role in conservation science by identifying biodiversity that may not be evident by morphology-based taxonomy and systematics. So-called cryptic species are particularly prevalent in freshwater environments, where isolation of dispersal-limited species, such as crayfishes, within dendritic river networks often gives rise to high intra- and inter-specific genetic divergence. We apply here a multi-gene molecular approach to investigate relationships among extant species of the crayfish genusPacifastacus, representing the first comprehensive phylogenetic study of this taxonomic group. Importantly,Pacifastacusincludes both the widely invasive signal crayfishPacifastacus leniusculus,as well as several species of conservation concern like the Shasta crayfishPacifastacus fortis. Our analysis used 83 individuals sampled across the four extantPacifastacusspecies (omitting the extinctPacifastacus nigrescens), representing the known taxonomic diversity and geographic distributions within this genus as comprehensively as possible. We reconstructed phylogenetic trees from mitochondrial (16S, COI) and nuclear genes (GAPDH), both separately and using a combined or concatenated dataset, and performed several species delimitation analyses (PTP, ABGD, GMYC) on the COI phylogeny to propose Primary Species Hypotheses (PSHs) within the genus. All phylogenies recovered the genusPacifastacusas monophyletic, within which we identified a range of six to 21 PSHs; more abundant PSHs delimitations from GMYC and ABGD were always nested within PSHs delimited by the more conservative PTP method.Pacifastacus leniusculusincluded the majority of PSHs and was not monophyletic relative to the otherPacifastacusspecies considered. Several of these highly distinctP. leniusculusPSHs likely require urgent conservation attention. Our results identify research needs and conservation priorities forPacifastacuscrayfishes in western North America, and may inform better understanding and management ofP. leniusculusin regions where it is invasive, such as Europe and Japan.

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Smith, Zoë F., Elizabeth A. James y Cassandra B. McLean. "In situ morphometric study of the Diuris punctata species complex (Orchidaceae), with implications for conservation". Australian Systematic Botany 21, n.º 4 (2008): 289. http://dx.doi.org/10.1071/sb08014.

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Taxa within the Diuris punctata species complex exhibit high levels of variation at both species and population level. Morphometric data collected in situ were used to investigate species boundaries of four Victorian Diuris species within the Diuris punctata species complex. Morphological characters and taxonomic groups identified in the present study were compared to those described under the current taxonomic treatment. Sixty-five multistate and continuous characters, including seven vegetative and 58 floral characters, were measured in situ across the range of each species within Victoria. The importance of flower colour in distinguishing taxa was highlighted but characters used were generally indiscrete. Certain characters used in current taxonomic descriptions, e.g. floral fragrance, were found to be uninformative. D. fragrantissima was confirmed as a separate taxon within the D. punctata group, justifying its recognition as a unique entity for conservation. Clustering of D. daltonii within D. punctata suggests that the recent elevation of the D. punctata var. daltonii to species level is not justified. The in situ measurement of morphological characters made it possible to incorporate sufficient sampling to encompass intra-specific and intra-population variation and is a feasible method to overcome sampling limitations encountered when herbarium specimens and limited destructive sampling are used.

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Moore, Abigail Mary, Samliok Ndobe y Inayah Yasir. "Importance of monitoring an endangered endemic species - intra-species biodiversity perspectives on the Banggai cardinalfish conservation and trade". IOP Conference Series: Earth and Environmental Science 681, n.º 1 (1 de marzo de 2021): 012120. http://dx.doi.org/10.1088/1755-1315/681/1/012120.

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Isajev, Vasilije, Vladan Ivetic, Aleksandar Lucic y Ljubinko Rakonjac. "Gene pool conservation and tree improvement in Serbia". Genetika 41, n.º 3 (2009): 309–27. http://dx.doi.org/10.2298/gensr0903309i.

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This paper presents the concepts applied in the gene pool conservation and tree improvement in Serbia. Gene pool conservation of tree species in Serbia includes a series of activities aiming at the sustainability and protection of genetic and species variability. This implies the investigation of genetic resources and their identification through the research of the genetic structure and the breeding system of individual species. Paper also includes the study of intra- and inter-population variability in experiments - provenance tests, progeny tests, half- and full-sib lines, etc. The increased use of the genetic potential in tree improvement in Serbia should be intensified by the following activities: improvement of production of normal forest seed, application of the concept of new selections directed primarily to the improvement of only one character, because in that case the result would be certain, establishment and management of seed orchards as specialized plantations for long-term production of genetically good-quality forest seeds, and the shortening of the improvement process by introducing new techniques and methods (molecular markers, somaclonal variation, genetic engineering, protoplast fusion, micropropagation, etc.).

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Youk, Seungyeon, Mingue Kang, Byeongyong Ahn, Yangmo Koo y Chankyu Park. "Genetic Diversity and Sequence Conservation of Peptide-Binding Regions of MHC Class I Genes in Pig, Cattle, Chimpanzee, and Human". Genes 15, n.º 1 (20 de diciembre de 2023): 7. http://dx.doi.org/10.3390/genes15010007.

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Comparative analyses of MHC gene diversity and evolution across different species could offer valuable insights into the evolution of MHC genes. Intra- and inter-species sequence diversity and conservation of 12 classical major histocompatibility complex (MHC) class I genes from cattle, chimpanzees, pigs, and humans was analyzed using 20 representative allelic groups for each gene. The combined analysis of paralogous loci for each species revealed that intra-locus amino-acid sequence variations in the peptide-binding region (PBR) of MHC I genes did not differ significantly between species, ranging from 8.44% for SLA to 10.75% for BoLA class I genes. In contrast, intraspecies differences in the non-PBRs of these paralogous genes were more pronounced, varying from 4.59% for SLA to 16.89% for HLA. Interestingly, the Shannon diversity index and rate of nonsynonymous substitutions for PBR were significantly higher in SLA and BoLA than those in Patr and HLA. Analysis of peptide-binding pockets across all analyzed MHC class I genes of the four species indicated that pockets A and E showed the lowest and highest diversity, respectively. The estimated divergence times suggest that primate and artiodactyl MHC class I genes diverged 60.41 Mya, and BoLA and SLA genes diverged 35.34 Mya. These results offer new insights into the conservation and diversity of MHC class I genes in various mammalian species.

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Malekian, Mansoureh. "Morphological assessment raises the possibility of cryptic species within the Luristan newt, Neurergus kaiseri (Amphibia: Salamandridae)". Herpetological Journal, Volume 29, Number 4 (1 de octubre de 2019): 237–44. http://dx.doi.org/10.33256/29.4.237244.

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One of the main challenges in the conservation of biodiversity is to overcome inadequate knowledge about species and their intra-specific diversity. In the present study, we attempted to assess morphological distinction of the two previously identified genetic clades within the Luristan newt (Neurergus kaiseri, Schmidt 1952) endemic to Iran, which is essential for its conservation planning. Signals of the morphological variation in N. kaiseri were evaluated using landmark-based geometric morphometrics of body shape and characters of osteological structures. Morphological approaches revealed consistent groupings within the species, confirming the presence of two distinct lineages (previously named as the northern and southern clades). The morphological and genetic data provide evidence for the possible co-existence of two species in N. kaiseri and we recommend assigning the newly recognised forms to the species level.

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Berger-Tal, Oded y David Saltz. "Invisible barriers: anthropogenic impacts on inter- and intra-specific interactions as drivers of landscape-independent fragmentation". Philosophical Transactions of the Royal Society B: Biological Sciences 374, n.º 1781 (29 de julio de 2019): 20180049. http://dx.doi.org/10.1098/rstb.2018.0049.

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Anthropogenically induced fragmentation constitutes a major threat to biodiversity. Presently, conservation research and actions focus predominantly on fragmentation caused directly by physical transformation of the landscape (e.g. deforestation, agriculture, urbanization, roads, etc.). While there is no doubt that landscape features play a key role in fragmenting populations or enhancing connectivity, fragmentation may also come about by processes other than the transformation of the landscape and which may not be readily visible. Such landscape-independent fragmentation (LIF) usually comes about when anthropogenic disturbance alters the inter- and intra-specific interactions among and within species. LIF and its drivers have received little attention in the scientific literature and in the management of wildlife populations. We discuss three major classes of LIF processes and their relevance for the conservation and management of species and habitats: (i) interspecific dispersal dependency, in which populations of species that rely on other species for transport and propagation become fragmented as the transporting species declines; (ii) interspecific avoidance induction, where species are excluded from habitats and corridors owing to interspecific interactions resulting from anthropogenically induced changes in community structure (e.g. exclusions by increased predation pressure); and (iii) intraspecific behavioural divergence, where populations become segregated owing to anthropogenically induced behavioural differentiation among them. This article is part of the theme issue ‘Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation'.

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Norman, Janette y Les Christidis. "Genetics and the conservation of Australian birds". Pacific Conservation Biology 3, n.º 3 (1997): 306. http://dx.doi.org/10.1071/pc970306.

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Molecular genetic techniques can be used to address a wide array of contemporary conservation problems encountered in the management of captive and wild bird populations. Most applications pertain to issues relevant to the management of populations or species. These range from sex identification in breeding programmes involving species in which the sexes are phenotypically monomorphic, to the identification of taxonomic diversity at the level of species, subspecies and populations. Additionally, comparative analyses of intra-population variation provide a means of identifying populations more at risk from inbreeding and a loss of diversity. This provides a more tractable approach for the conservation and management of genetic diversity than derived from theoretical considerations about the genetic consequences of small population size. A recent development away from these traditional species-based approaches is the use of information revealed by studies of comparative phylogeography to address issues relevant to the management of entire communities and ecosystems. Molecular studies of non-threatened taxa are also an important tool for wildlife management. Nonthreatened species can be used as indicators of regional biodiversity or to provide information which will assist in the conservation of a closely related species. Molecular studies of apparently widespread and abundant species may also reveal previously unrecognized taxonomic diversity of significance for conservation. With the impressive array of molecular tools now available for addressing issues in conservation biology it is important that they not be applied indiscriminately. Careful consideration needs to be given to the specific needs of wildlife management and the appropriateness of genetic studies should be evaluated on a case by case basis. In some instances molecular studies may not be warranted, providing little information beyond that which has been obtained from ecological and demographic studies or contained in traditional taxonomies.

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D’Iglio, Claudio, Sabrina Natale, Marco Albano, Serena Savoca, Sergio Famulari, Claudio Gervasi, Giovanni Lanteri, Giuseppe Panarello, Nunziacarla Spanò y Gioele Capillo. "Otolith Analyses Highlight Morpho-Functional Differences of Three Species of Mullet (Mugilidae) from Transitional Water". Sustainability 14, n.º 1 (31 de diciembre de 2021): 398. http://dx.doi.org/10.3390/su14010398.

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Otoliths are used in taxonomy and ichthyology as they can provide a wide range of information about specimens. They are an essential tool to monitor the most sensitive species for a sustainable exploitation level. Despite the increasing use of sagittae in research, their inter- and intra-specific variability and eco-functionality are still poorly explored. This paper aims to investigate the inter- and intra-specific variability of Mugilidae sagittae using morphological and morphometrical analysis, as well as scanning electron microscopy and shape analysis. The sagittae of 74 specimens belonging to three different Mugilidae species, collected from a coastal lagoon, were analyzed to give an accurate description of their morphology, morphometry, shape and crystalline habits. The results highlighted the intra- and inter-specific variability of sagittae, showing morphometrical differences among species and slight differences between left and right sagittae in C. labrosus individuals. Moreover, SEM images showed a peculiar crystal organization, with several different crystal habits and polymorphs. This study provides an accurate description of sagittae in the studied species, deepening the knowledge on inter- and intra-specific variations and crystal habits and providing data which will be useful for future studies on otoliths. With this data, it will be possible to improve conservation and exploitation sustainability in sensitive habitats.

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Bertoni, Bianca Waléria, Ana Valéria de Souza, Ronaldo Biondo, Suzelei de C. França, Mariana PC Telles y Ana Maria S. Pereira. "Genetic diversity among natural populations of Mandevilla velutina". Horticultura Brasileira 28, n.º 2 (junio de 2010): 209–13. http://dx.doi.org/10.1590/s0102-05362010000200012.

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Mandevilla velutina (Mart. Ex Stadelm) Woodson (Apocynaceae) is an endemic species in the Cerrado (Brazilian Savannah), whose alcoholic extracts and root infusions are extensively used in the popular medicine to treat inflammatory diseases and against snake bites. Currently, this species has been pointed out as crucial in conservation programs. Therefore, studies on its genetic diversity, as well as the development of methodology for in vitro conservation in germplasm banks are imperative to avoid its extinction. The objective of this work was to investigate the intra- and inter-populational genetic variability of M. velutina to enhance the representativeness of germplasm banks. To this aim, we used RAPD molecular markers. The analysis of molecular variance (AMOVA) indicated that the intra-populational (81.25%) was higher than the inter-populational (18.75%) variability, which was confirmed by the Nei's Diversity Index. The PHIst (0.188) and qP (0.1586) values of genetic variation indicated high population structuring. There seems to be no direct correlation between geographic distances and genetic similarity among the three studied populations.

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Vitule, Jean R. S., Thiago V. T. Occhi, Bin Kang, Shin-Ichiro Matsuzaki, Luis Artur Bezerra, Vanessa S. Daga, Larissa Faria, Fabrício de A. Frehse, Felipe Walter y André A. Padial. "Intra-country introductions unraveling global hotspots of alien fish species". Biodiversity and Conservation 28, n.º 11 (2 de julio de 2019): 3037–43. http://dx.doi.org/10.1007/s10531-019-01815-7.

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Lee, Jennifer E. y Steven L. Chown. "Quantification of intra-regional propagule movements in the Antarctic". Antarctic Science 23, n.º 4 (3 de marzo de 2011): 337–42. http://dx.doi.org/10.1017/s0954102011000198.

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AbstractManagement of non-native species introductions is a conservation priority in the Antarctic region. However, despite the recognised importance of intra-regional propagule transfer, the majority of studies have focused on inter-regional pathways (i.e. from outside of the Antarctic region). Here we quantify the number of seeds carried by expeditioners who have visited sub-Antarctic Marion Island. We recorded 420 seeds from 225 items of clothing, with seeds found on 52% of the items and soil on 45% of them. The median number of seeds for field-based and station-based personnel was 20.5 and 3 per person, respectively. Waterproof trousers and socks, particularly those of field workers, carry the greatest number of propagules (for field workers, medians of 5 and 6.5, respectively) and therefore should be the focus of intra-regional management interventions. Amongst the seeds found entrained within clothing several were from species which are widespread aliens in the Antarctic region including Agrostis stolonifera, Poa annua and Sagina procumbens, and indigenous zoochorous species (Acaena magellanica, Uncinia compacta) were also well represented. The present data provide quantitative evidence in support of previous, largely hypothetical concerns about the risks of intra-regional propagule transfer in the Antarctic.

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Scarano, Fabio Rubio, Cláudia Franca Barros, Roberta Kuan Tchuen Loh, Eduardo Arcoverde de Mattos y Tânia Wendt. "Plant morpho-physiological variation under distinct environmental extremes in restinga vegetation". Rodriguésia 60, n.º 1 (marzo de 2009): 221–35. http://dx.doi.org/10.1590/2175-7860200960113.

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ABSTRACT This paper is a synthesis of over ten years of research on inter- and intra-population variation in morphophysiology of six plant species at the Jacarepiá restinga: the shrubs Alchornea triplinervia, Andira legalis, Clusia fluminensis and Myrsine parvifolia, the bromeliad Aechmea maasii (formerly identified as Aechmea bromeliifolia, now recognized as a species only found in Central Brazil) and the geophyte palm Allagoptera arenaria. Individual shape, stature and growth, leaf anatomy, photoinhibition, and carbon, nitrogen and water use were the main parameters studied. The isolated study of intra-specific variation in one or a few of the above-mentioned traits often does not allow a distinction between acclimation and stress symptoms. Thus, we used an approach that integrated morphology, anatomy, physiology and also population parameters. Variation in morphological, anatomical and physiological traits was found for the majority of these species, and often indicated great acclimation capacity to distinct environmental extremes. This acclimation capacity may be partly responsible for the broad colonization success of extreme habitats in restingas, by species often originating in mesic forest environments. This phenomenon is an additional element to be accounted for as an important component of the high biodiversity of the Atlantic forest complex. Finally, we discuss implications for biodiversity conservation of intra-specific variation at the population level.

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VAN DUSEN, M. ERIC y J. EDWARD TAYLOR. "Missing markets and crop diversity: evidence from Mexico". Environment and Development Economics 10, n.º 4 (18 de julio de 2005): 513–31. http://dx.doi.org/10.1017/s1355770x05002317.

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Recent micro-economic studies of in situ conservation of crop diversity focus on competition between modern and traditional varieties of major food crops. Our paper offers a different, crop system, approach and a limited-dependent variable econometric technique to model in situ conservation of both intra- and infra-species crop diversity in a context of heterogeneous ecological and market environments, using unique household-farm data from Mexico. Our findings reject separability and indicate that market integration significantly reduces crop diversity. They underline the importance of studying diversity in the context of larger cropping systems and economic environments.

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Paredes, Estefanía, Sara Campos, Alba Lago, Tracy Bueno, Julien Constensoux y Damian Costas. "Handling, Reproducing and Cryopreserving Five European Sea Urchins (Echinodermata, Klein, 1778) for Biodiversity Conservation Purposes". Animals 12, n.º 22 (16 de noviembre de 2022): 3161. http://dx.doi.org/10.3390/ani12223161.

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In this work, five local sea urchin species found in European waters were studied. Four were regular species: Sphaerechinus granularis, Psammechinus miliaris, Echinus esculentus (Linnaeus, 1758) and the edible sea urchin Paracentrotus lividus; and one was an irregular species, Echinocardium cordatum. These five species of sea urchins have been studied regarding their fertility, toxicity of cryoprotecting agents, cryopreservation of different cell types and chilling injury. The baseline fertility is similar in P. lividus, P. miliaris and S. granularis. Nonetheless, the sperm:egg ratio, contact time and development of the fertilization envelope would need to be studied further on a case-by-case basis. Sperm can be maintained inactively in the gonad (4 °C), and oocytes also maintain quality in sea water (4 °C), even after 72 h. Sperm was cryopreserved for four species with some post-thaw intra specific variability, and embryo cryopreservation was only possible for S. granularis. Overall, this study provided a wider vision of the biology and reproduction of these species that will help us develop tools for their biodiversity conservation through cryopreservation.

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Junqing, Li. "Studies on intra and inter species gene diversity of Chinese beeches". Biodiversity Science 04, n.º 2 (1996): 63–68. http://dx.doi.org/10.17520/biods.1996010.

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Sarasa, M. "Trophy hunting, size, rarity and willingness to pay: inter–specific analyses of trophy prices require reliable specific data". Animal Biodiversity and Conservation 36, n.º 2 (diciembre de 2013): 165–75. http://dx.doi.org/10.32800/abc.2013.36.0165.

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Awareness of the importance of the wildlife trade and human perception in animal conservation is growing. Recent studies carried out on a continental and world scale have analysed the associations between trophy score, rarity and prices. As a large range of ungulates are legally hunted throughout the world and numerous ungulate taxa are threatened, the relationship between rarity and trophy prices has been studied in several species. This article briefly reviews verifiable data on species and trophy prices and compares findings with data used in recent articles. The findings show that several elements of intra–specific data were inadequately addressed and that the trophy prices considered were not necessarily representative of real trophy prices. Furthermore, the body mass used for numerous taxa did not fit current knowledge of species, and several subspecies and rarity indexes that were considered disagreed with recognized subspecies or with the real conservation status of taxa. Thus, caution should be taken when considering some reported results. To improve our understanding of the associations between wildlife trade and wildlife conservation, further studies should take into account reliable specific data, such as that from government agencies, rather than publicity data.

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Ford, Bruce A., Anne C. Worley, Robert F. C. Naczi y Habibollah Ghazvini. "Amplified fragment length polymorphism analysis reveals high genetic variation in the Ouachita Mountain endemic Carex latebracteata (Cyperaceae)". Botany 87, n.º 8 (agosto de 2009): 770–79. http://dx.doi.org/10.1139/b09-034.

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Species with limited geographic ranges are often of conservation concern because they may possess low levels of genetic variability and thus have a reduced ability to respond to stochastic events. As a consequence, an important conservation strategy is to maximize a species’ adaptive potential by preserving natural levels of genetic variation. With this goal in mind, we assessed genetic variation within and among six populations of the Ouachita Mountain endemic Carex latebracteata Waterfall using 653 amplified fragment length polymorphism (AFLP) loci. Indices of genetic variation [% polymorphic loci, expected heterozygosity (HE), population differentiation (ΦPT)] were most consistent with an outcrossing or mixed mating system despite an inflorescence morphology that seems conducive to self-pollination. An analysis of molecular variance (AMOVA) showed that >80% of the variation occurred within populations, suggesting high levels of gene flow. The close geographic proximity of most populations, which are often adjacent to streams, may facilitate long-distance seed dispersal and help to maintain high intra-population genetic variation. Conservation strategies focused on maintaining the ecological integrity of rivers and streams, and the provision of naturally vegetated buffers would likely assist in the conservation of this and other Ouachita Mountain endemics.

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Rodrigues, Luanna Lorenna Vieira y Alexsandra Fernandes Pereira. "Potential and Reality of Cryopreserving Somatic Cells of Wild Felids for Conservation". Cryoletters 44, n.º 5 (1 de septiembre de 2023): 249–57. http://dx.doi.org/10.54680/fr23510110112.

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The loss of biodiversity caused by anthropogenic actions is also a reality for the members of the Felidae family. Except for the domestic cat, all felid species have some degree of threat of extinction in their natural habitat. For this reason, felids have been included in conservation-related studies. This scenario has aroused increasing interest in the formation of somatic cell banks, which when efficiently implemented can be used in preservation strategies for the species. Nevertheless, one of the important steps in the formation of these banks is the understanding of the technical principles and variations involved in cryopreservation techniques, especially because cryopreservation increases the possibilities for Assisted Reproduction Technologies (ARTs) by making the use of biological materials independent of time and space. In wild felids, several species already have promising results in the formation of somatic cell banks, and studies aimed at better viability rates have been constantly proposed, as well as new species have been studied. In some species, aspects involved in successful cryopreservation are already well defined, and slow freezing associated with cryoprotectant solutions composed of intra- and extracellular substances is the most useful approach. The aim of this review was to present the main parameters involved in the elaboration of a somatic cell cryopreservation protocol and their effects, as well as to address the main results achieved for different wild felids.

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Dutt Joshi, B., G. Jabin, A. Sharief, V. Kumar, T. Mukherjee, M. Kumar, A. Singh et al. "Genetic evidence for allopatric speciation of the Siberian ibex Capra sibirica in India". Endangered Species Research 42 (14 de mayo de 2020): 1–5. http://dx.doi.org/10.3354/esr01034.

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Montane systems, formed by a series of climatic oscillations and temporal topographic metamorphoses, have broken up the contiguous distribution of widespread species and accelerated allopatric speciation. We used a partial fragment of the mitochondrial cytochrome b (cytb) gene to address speciation across the entire range of the Siberian ibex Capra sibirica. We demonstrated that the Siberian ibex is a polytypic species, plausibly formed by a combination of at least 2 species and/or 3 to 4 sub-species. Bayesian phylogeny showed that the Indian-Tajikistan (I-T) clade is adequately diverged from the other clades based on the mean intra-specific distance criterion, and warrants recognition as a distinct species. We provide pragmatic evidence for the endorsement of the I-T clade as a distinct species of Siberian ibex and urge prioritization of the conservation of this species at global and regional scales.

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Rajičić, Tatjana Sretenović, Theo van Hintum, Aleš Lebeda y Klaus J. Dehmer. "Analysis of wild Lactuca accessions: conservation and identification of redundancy". Plant Genetic Resources: Characterization and Utilization 6, n.º 02 (25 de junio de 2008): 153–63. http://dx.doi.org/10.1017/s1479262108993163.

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Germplasm accessions of wildLactucaspecies are maintained worldwide inex situcollections as gene reservoirs for quality and disease resistance traits for cultivated lettuce. Accessions of 12Lactucaspecies from 6 genebanks were compared via morphological characterization and AFLP (Amplified Fragment Length Polymorphism)-based profiling to estimate the extent of duplication. A method of assessing redundancy within very similar, but not identical accessions, is proposed, based on 352 polymorphic AFLP products. Seven duplication groups showed a high level of AFLP similarity, and one pair ofLactuca salignaaccessions displayed identical AFLP profiles. In several cases, the morphological assessment indicated that a taxonomic reclassification of accessions was necessary. Candidate duplicates were identified using population parameters and inter- and intra-accession variability. The implications of these findings on the conservation of wild species are discussed.

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Mayr, B., D. Schweizer, M. Mendelak, J. Krutzler, W. Schleger, M. Kalat y H. Auer. "Levels of conservation and variation of heterochromatin and nucleolus organizers in the Bovidae". Canadian Journal of Genetics and Cytology 27, n.º 6 (1 de diciembre de 1985): 665–82. http://dx.doi.org/10.1139/g85-101.

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Chromomycin A3 banding of the mitotic sets of 10 species of Bovidac (cattle, wisent, yak, banteng, gaur, red buffalo, swamp buffalo, sheep, mufflon, and goat) serves to demarcate both centromeric constitutive heterochromatin and R-banding patterns capable of identifying all the chromosomes within a given complement. In all species significant amounts of chromomycin-bright heterochromatin are present at the centromeres of all autosomes, though there was a high degree of intra- and inter-individual variation in the size of the heterochromatic blocks. Marked interspecies differences in the centromeric patterns were evident. The X chromosomes contained appreciable amounts of centromeric heterochromatin only in the two buffaloes. All the animals studied lacked distamycin A – diamidinophenylindole type heterochromatin. AgNO3 staining was applied sequentially to detect the location of active nucleolus organizer regions (NORs). The distribution of NORs was reasonably conservative in most of the species. An exceptional situation was found in the two buffaloes, where only one NOR pair matched with the standard karyotype of the Bovidae.Key words: heterochromatin, chromomycin A3 fluorescence, nucleolus organizers, Bovidae.

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27

Coelho, Marcos Vinícius, Camila Cupello, Paulo M. Brito y Olga Otero. "Living Taxa and Their Importance in Understanding the Extinct Diversity: A Look at Polypterid Pinnules". Diversity 15, n.º 4 (3 de abril de 2023): 517. http://dx.doi.org/10.3390/d15040517.

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Pinnules are the peculiar, impaired spines that carry each of the numerous finlets that constitute the dorsal fins of polypterid fishes (Cladistia and Polypteriformes). Previous studies, including a recent detailed paper on the comparative analysis of the morphology of pinnules in most of the extant species (genera Polypterus and Erpetoichthys), suggest that they display unique characteristics that allow for species identification. Since most of the polypterid fossil records are composed of scales that lack specific characteristics and isolated pinnules, this work aims to test their taxonomic relevance before comparing the fossil pinnule morphologies across the fossil records in order to evaluate polypterid paleodiversity. Therefore, we describe the intra-individual and intra-specific morphological variations of the pinnules in the extant species Polypterus bichir. Furthermore, we compared it with the various morphologies described in the Polypteridae family. We report intra-individual variability related to the anteroposterior axis of the dorsal fin. We also report morphological differences in the pinnules among specimens that overlap those anticipated among different species, concluding that the pinnule morphology cannot support taxonomic purposes in polypterid fishes in their current state.

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28

Dillon, Sally L., Peter K. Lawrence y Robert J. Henry. "The new use of Sorghum bicolor-derived SSR markers to evaluate genetic diversity in 17 Australian Sorghum species". Plant Genetic Resources 3, n.º 1 (abril de 2005): 19–28. http://dx.doi.org/10.1079/pgr200454.

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The Sorghum genus is extremely diverse both morphologically and geographically, however, relatively few of the 25 recognized species have been evaluated genetically. The apparent lack of basic knowledge pertaining to the levels of genetic diversity both within and between the 17 Australian wild species is a major obstacle to both their effective conservation and potential use in breeding programmes. Twelve Sorghum bicolor-derived simple sequence repeat (SSR) markers were evaluated for cross-species amplification in all 25 Sorghum species. The SSR markers were highly polymorphic, with diversity indices ranging from 0.59 to 0.99 with mean of 0.91. Five markers combined were able to differentiate 24 of the 25 Sorghum species, with intra-species polymorphism apparent. Sorghum bicolor-derived SSRs have proven to be an efficient source of markers for genetic diversity studies of the relatively poorly characterized Australian indigenous Sorghum species.

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29

Orozco-terWengel, Pablo, Ylenia Chiari, David R. Vieites, Miguel Pedrono y Edward Louis Jr. "Isolation and characterization of six polymorphic microsatellite loci for the Malagasy spider tortoise, Pyxis arachnoides and cross-amplification in Pyxis planicauda". Amphibia-Reptilia 34, n.º 1 (2013): 125–28. http://dx.doi.org/10.1163/15685381-00002866.

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Pyxis arachnoides is a Critically Endangered Malagasy tortoise for which little data about its natural history and genetic variation are available. This lack of knowledge complicates undertaking conservation measures considering Pyxis genetic diversity. Here, we describe six new microsatellites for Pyxis arachnoides from wild specimens and several localities, and the cross amplification of two Astrochelys radiata microsatellites. Of these microsatellites, two are monomorphic among the three distinct subspecies and a closely related species, while the remaining six are polymorphic. Microsatellite data are needed for this species to study the inter- and intra-subspecies genetic diversity, especially for the highly endangered subspecies P. a. brygooi, which currently occurs only in remote localities. The availability of polymorphic microsatellites will allow identifying the population of origin of individuals and will aid in justifying their management as separate evolutionary lineages for conservation purposes. The rationale is to preserve both evolutionary processes and adaptive potential.

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30

Habil, Gyorgy Deak, Elena Holban, Abdulhusei Jawdhari y Isabela Sadîca. "Review on Polypodium Hydriforme Infestation of Sturgeon Eggs and Its Implications in Species Conservation". E3S Web of Conferences 437 (2023): 02007. http://dx.doi.org/10.1051/e3sconf/202343702007.

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Polypodium hydriforme is the only known parasite adapted to intra-cellular parasitism of sturgeon oocytes, thus affecting the delicate life balance of these endangered species. Aquatic ecosystems are often shaped by intricate interactions between various organisms, each playing a distinct role in the overall health and sustainability of the environment, parasites on the other hand pose no beneficial roles and are a threat especially for fragile or declining species. Sturgeons, which are endangered and ecologically important fish species, serve as hosts for this parasite during their crucial reproductive phase. The presence of Polypodium hydriforme in sturgeon eggs has prompted investigations into its effects on both the host’s reproductive success and the broader aquatic ecosystem. Stating the intricacies of this parasitic interaction is essential not only for unravelling its evolutive adaptations but also for ensuring the conservation of sturgeon populations and the preservation of aquatic biodiversity as a whole.

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31

Mossi, AJ, RL Cansian, O. Leontiev-Orlov, EM Zanin, CH Oliveira, ML Cechet, AZ Carvalho y S. Echeverrigaray. "Intra and inter populational genetic variability in Maytenus ilicifolia Mart. ex Reiss. 1861, through RAPD markers". Brazilian Journal of Biology 67, n.º 4 suppl (diciembre de 2007): 957–61. http://dx.doi.org/10.1590/s1519-69842007000500022.

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Maytenus ilicifolia is a medicinal plant largely used in the South Brazilian folk medicine. The aim of this study was to quantify the intra and inter populational genetic variability in three populations of M. ilicifolia, focusing on the genetic conservation of this species, which has been threatened by anthropic action. RAPD (Random Amplified Polymorphic DNA) markers were used to analyze 30 plants of each of the three populations collected in the Alto Uruguai Gaúcho region. Fourteen selected primers generated a total of 158 bands, 71.5% of which were polymorphic. The comparison of Jaccard’s distances showed that the intra populational variation was higher than the inter populational variability, and cluster analysis allowed the separation of the three populations. Just 7.6% of the bands were specific of at least two populations. Data indicate that the analyzed M. ilicifolia populations represent a single genetic pool, and therefore any of the population thoroughly can represent the overall genetic variability of the species in the sampled region.

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32

Naim, Adnan, Surya Kanta Mishra, Anjan Sahoo y Indra mani Nath. "Male Gonads Transplantation from Kadaknath Chicken to Chicken and Duck Surrogates". Genes 14, n.º 5 (16 de mayo de 2023): 1094. http://dx.doi.org/10.3390/genes14051094.

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Transplantation of the gonadal tissue of male and female avian species, such as chicken, onto suitable surrogates and production of live offspring has been successfully demonstrated as a strategy for the conservation and re-constitution of valuable chicken germplasm. The main objective of this study was to establish and develop the male gonadal tissue transplantation technology for the conservation of the indigenous chicken germplasm. The male gonads of the Indian native chicken breed, Kadaknath (KN), were transplanted from a day-old donor to a recipient white leghorn (WL) chicken, and Khaki Campbell (KC) ducks, as surrogates. All the surgical interventions were performed under permitted general anaesthesia, and the chicks, upon recovery, were reared with and without immunosuppressant. The recipient surrogates for the donor KN gonads were housed and reared for 10–14 weeks, and post-sacrifice, developed gonadal tissues were harvested to squeeze out the fluid to perform artificial insemination (AI). The AI-entailed fertility test using the recovered seminal extract from the transplanted KN testes from both surrogate species (KC ducks and WL males), used against KN purebred females, remained very close to the percent fertility realised from purebred KN chickens (controls). These initial results revealed from this trial study suggest definitively that, Kadaknath male gonads were readily accepted and grown inside the intra- and inter-species surrogate host, WL chicken and KC ducks, demonstrating a suitable intra- and inter-species donor-host system. Furthermore, the developed transplanted male gonads of KN chicken into the surrogates were found to have the potential to fertilise the egg and give rise to pure-line KN chicks.

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33

Bertuzzi, Tania, Diego López-Spahr, Carlos A. Gómez, Silvia Sühring, Gisela Malagrina, Carol C. Baskin y Guadalupe Galíndez. "Variation in Seed Dormancy of Chaco Seasonally Dry Forest Species: Effects of Seed Traits and Population Environmental Conditions". Plants 12, n.º 9 (27 de abril de 2023): 1790. http://dx.doi.org/10.3390/plants12091790.

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The persistence of subtropical seasonally dry forests urgently requires the implementation of ex situ conservation and restoration programs. We studied variation in seed traits and dormancy of six native species growing in seasonally dry Chaco forests of Argentina. We documented high intra- and interspecific variability in seed traits and dormancy. Fresh seeds of Geoffroea decorticans and Parasenegalia visco (Fabaceae) were water-permeable and nondormant (ND), while those of Parkinsonia praecox and Vachellia aroma (Fabaceae) were water-impermeable and had physical dormancy (PY). Seeds of Schnopsis lorentzii (Anacardiaceae) and Sarcomphalus mistol (Rhamnaceae) were water-permeable and had physiological dormancy (PD). Mechanical and chemical scarification were the most effective methods to break PY, and dry storage for 3 months was effective in breaking PD. Seeds of large-seeded species were ND or had PD, and those of small-seeded species had PY. Species inhabiting moist habitats had ND seeds, whereas those from seasonally dry habitats had seeds with PY or PD. These results suggest that seed traits and dormancy are species-specific and that intraspecific variation in seed traits is likely associated with high phenotypic plasticity of species in response to local environmental heterogeneity. These findings should be considered at the time of implementation of conservation techniques and for seed sourcing decisions for restoration.

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34

Acharya, Gobinda Chandra, Sansuta Mohanty, Madhumita Dasgupta, Supriya Sahu, Satyapriya Singh, Ayyagari V. V. Koundinya, Meenu Kumari, Ponnam Naresh y Manas Ranjan Sahoo. "Molecular Phylogeny, DNA Barcoding, and ITS2 Secondary Structure Predictions in the Medicinally Important Eryngium Genotypes of East Coast Region of India". Genes 13, n.º 9 (19 de septiembre de 2022): 1678. http://dx.doi.org/10.3390/genes13091678.

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Commercial interest in the culinary herb, Eryngium foetidum L., has increased worldwide due to its typical pungency, similar to coriander or cilantro, with immense pharmaceutical components. The molecular delimitation and taxonomic classification of this lesser-known medicinal plant are restricted to conventional phenotyping and DNA-based marker evaluation, which hinders accurate identification, genetic conservation, and safe utilization. This study focused on species discrimination using DNA sequencing with chloroplast–plastid genes (matK, Kim matK, and rbcL) and the nuclear ITS2 gene in two Eryngium genotypes collected from the east coast region of India. The results revealed that matK discriminated between two genotypes, however, Kim matK, rbcL, and ITS2 identified these genotypes as E. foetidum. The ribosomal nuclear ITS2 region exhibited significant inter- and intra-specific divergence, depicted in the DNA barcodes and the secondary structures derived based on the minimum free energy. Although the efficiency of matK genes is better in species discrimination, ITS2 demonstrated polyphyletic phylogeny, and could be used as a reliable marker for genetic divergence studies understanding the mechanisms of RNA molecules. The results of this study provide insights into the scientific basis of species identification, genetic conservation, and safe utilization of this important medicinal plant species.

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35

Wasko, Adriane Pinto y Pedro Manoel Galetti Jr. "Mapping 18S ribosomal genes in fish of the genus Brycon (Characidae) by fluorescence in situ hybridization (FISH)". Genetics and Molecular Biology 23, n.º 1 (marzo de 2000): 135–38. http://dx.doi.org/10.1590/s1415-47572000000100025.

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The present study provides data on the nucleolar organizer regions (NORs) of seven Brycon species based on mapping of the 18S rRNA genes by fluorescence in situ hybridization (FISH). Fluorescent signals were observed on the telomere of the long arm of two large submetacentric chromosomes, thus confirming the number and location of NORs previously revealed by other classical cytogenetic techniques. Although there were no inter- or intra-individual variations in the number and location of the 18S loci, NOR size polymorphism was observed between homologous chromosomes. The clustering and conservation of NORs in a single chromosome pair indicates a high level of NOR stability among species of the genus Brycon.

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36

Eisenberg, Tobias, Ahmad Fawzy, Ute Kaim, Anne Nesseler, Karin Riße, Iris Völker, Silke Hechinger et al. "Chronic wasting associated with Chlamydia pneumoniae in three ex situ breeding facilities for tropical frogs". Antonie van Leeuwenhoek 113, n.º 12 (5 de noviembre de 2020): 2139–54. http://dx.doi.org/10.1007/s10482-020-01483-6.

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AbstractA number of different Chlamydia spp. have been detected in the class Amphibia with C. pneumoniae being the predominant species involved. Chlamydiae have been linked to mass mortality events, thereby representing significant pathogens that deserve attention with respect to worldwide amphibian decline. We here present six cases of chlamydiosis and asymptomatic chlamydial infections in different frog species from three ex situ amphibian conservation facilities. Clinical signs predominantly characterised by regurgitation, chronic wasting, lethargy and suspended breeding were associated with C. pneumoniae infection. Despite various treatment regimens, it was not possible to clear infections. However, intra vitam diagnostics succeeded from skin, faeces and urine for the first time.

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37

Pérez-Méndez, Néstor, Airam Rodríguez y Manuel Nogales. "Intra-specific downsizing of frugivores affects seed germination of fleshy-fruited plant species". Acta Oecologica 86 (enero de 2018): 38–41. http://dx.doi.org/10.1016/j.actao.2017.11.017.

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38

Allen, Maximilian L., Alexandra C. Avrin, Morgan J. Farmer, Laura S. Whipple, Emmarie P. Alexander, Alyson M. Cervantes y Javan M. Bauder. "Limitations of current knowledge about the ecology of Grey Foxes hamper conservation efforts". Journal of Threatened Taxa 13, n.º 8 (26 de julio de 2021): 19079–92. http://dx.doi.org/10.11609/jott.7102.13.8.19079-19092.

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Species-specific conservation is important for maintaining the integrity of ecological communities but is dependent on sufficiently understanding multiple aspects of a species’ ecology. Species-specific data are commonly lacking for species in geographic areas with little research and species perceived to have insufficient charisma or economic importance. Despite their widespread distribution across central and North America and status as a furbearing mammal, little is known about the ecology of Grey Foxes Urocyon cinereoargenteus compared to other species of furbearing mammals. To understand what is known about this species, especially factors affecting population dynamics, we performed a systematic review of the scientific literature. We found 234 studies about Grey Foxes, with studies increasing substantially over time but with geographic gaps in the Great Plains and most of Mexico and central America. Most studies we reviewed examined relative abundance or occupancy (n= 35), habitat associations (n= 30), primarily as part of larger mammalian community studies, or spatiotemporal effects of other mammalian carnivores (n= 19), predominately Coyote Canis latrans. Grey Foxes were primarily forest-associated although associations with specific forest communities or anthropogenically disturbed habitats varied among studies. Multiple studies across ecoregions reported this fox as among both the most- and least-abundant mammalian carnivore. The inter-specific effects of Coyote were often, but not exclusively, negative and were likely mediated by landscape composition and human development. Importantly, very few studies examined population-effects of coyotes on Grey Foxes. Studies of population trends, demographics, and space use of Grey Foxes were comparatively rare and small inter- and intra-study sample sizes limited our ability to infer broader patterns. We suggest multiple avenues for future research to better understand the population status of this species throughout their range.

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39

Brambilla, M. y D. Rubolini. "Intra-seasonal changes in distribution and habitat associations of a multi-brooded bird species: implications for conservation planning". Animal Conservation 12, n.º 1 (febrero de 2009): 71–77. http://dx.doi.org/10.1111/j.1469-1795.2008.00226.x.

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40

Lorenz, Heike, Thorsten Reinsch, Christof Kluß, Friedhelm Taube y Ralf Loges. "Does the Admixture of Forage Herbs Affect the Yield Performance, Yield Stability and Forage Quality of a Grass Clover Ley?" Sustainability 12, n.º 14 (20 de julio de 2020): 5842. http://dx.doi.org/10.3390/su12145842.

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It is unclear whether the use of multi-species swards is a suitable measure for climate change adaptation by achieving high and stable dry matter (DM) production and good forage quality in grazing systems. The objective of the study is to evaluate whether a complex rather than a simple grass clover mixture enhances performance under nitrogen (N)-deficient conditions due to greater diversity in plant functional traits. During a four-year field experiment, a three-species and a seven-species grass clover mixture were compared under one cutting-for-conservation and two simulated grazing (defoliation every three or four weeks) treatments. The results revealed a similarity in the DM yields of both seed mixtures, indicating that in the given conditions the species in the simple mixture already offered crucial yield-determining functional traits. Different growth patterns, however, led to higher intra-annual yield stability in the complex mixture. In the cutting-for-conservation system, DM yields were higher, but this came at the expense of reduced metabolisable energy and crude protein contents and lower inter-annual yield stability. We conclude that higher seeding costs for multi-species mixtures are compensated by greater yield stability while offering the potential for additional eco-system services like enhanced carbon sequestration and diverse food for pollinators.

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41

Moura, Teresa, Mónica C. Silva, Ivone Figueiredo, Ana Neves, Pablo Durán Muñoz, Maria Manuela Coelho y Leonel S. Gordo. "Molecular barcoding of north-east Atlantic deep-water sharks: species identification and application to fisheries management and conservation". Marine and Freshwater Research 59, n.º 3 (2008): 214. http://dx.doi.org/10.1071/mf07192.

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Two genera of elasmobranchii, Centrophorus and Centroscymnus, include species that represent the highest landings of deep-water sharks caught by fishing fleets operating in the north-east Atlantic. There are morphology-based identification problems among and within genera, and landings of processed shark products further prevent an objective assessment of these species. The present study is the first attempt to test the suitability of using a DNA barcode approach to discriminate accurately among the four most important commercial deep-water shark species: Centrophorus squamosus, Centrophorus granulosus, Centroscymnus coelolepis and, recently discovered in Portuguese ports, Centroscymnus owstoni. Sequence analyses of the mitochondrial DNA cytochrome c oxidase subunit I (COI) gene revealed low levels of haplotypic and genetic diversities. Higher levels of inter-specific relative to intra-specific divergences allowed discrimination among species, which form reciprocally monophyletic clades. Inclusion of published COI sequences from other species within the same genera revealed haplotype sharing among species, which calls into question the current taxonomy and accuracy of fisheries data available. Amplification of the COI gene coupled with MboI restriction digests was found to be a fast and inexpensive strategy to resolve within genera identification problems. Molecular barcoding constitutes a critical tool for the assessment and implementation of urgent management policies for this group of species.

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42

Prowse, Thomas A. A. y Barry W. Brook. "Climate change, Variability and Conservation impacts in Australia." Pacific Conservation Biology 17, n.º 3 (2011): 168. http://dx.doi.org/10.1071/pc110168.

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Australian conservation scientists, managers and decision makers must come to grips with anthropogenic climate change, imposed upon an already variable regional climate system. Pre- and post-instrumental records and climate proxies indicate that Australia has experienced wet and dry cycles over intra-decadal to millennial time scales. Precipitation variation across Australia is correlated with different climate features but reliable tools for seasonal rainfall prediction are still some years away. Atmosphere-Ocean General Circulation Models predict a widening of the Hadley circulation and strengthening of the Southern Annular Mode, which should result in reduced cool season rainfall over southern Australia. Shifts in the Australian climate over the Holocene epoch, most notably increased ENSO variability after 5 000 years ago, are associated with substantial vegetation change and indicate the speed at which ecosystems may be altered. The CO2 fertilization of plant biomes may mitigate increasing aridity to some extent but, in general, climate change is expected to negatively affect native vegetation and agricultural productivity. Sea-level rise is predicted to be substantial over this century and, when coupled with increased storm intensity, poses threats in the form of erosion, salinization and flooding. The best chance of building adaptable ecosystems and preserving ecosystem services requires the extension, integration and possibly optimization of reserve systems, in concert with improved management of other threatening processes (habitat loss, invasive species, overexploitation, pollution and disease). In addition, a price on carbon dioxide emissions would provide incentives for privately funded reforestation schemes, but additional incentives promoting mixed species over monoculture plantings would be required to assure maximum biodiversity benefits.

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43

Shuai, Fangmin, Shixiao Yu, Sovan Lek y Xinhui Li. "Habitat effects on intra-species variation in functional morphology: Evidence from freshwater fish". Ecology and Evolution 8, n.º 22 (25 de octubre de 2018): 10902–13. http://dx.doi.org/10.1002/ece3.4555.

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44

Lv, Ting, Rong Zhao, Ning-jie Wang, Lei Xie, Yue-yao Feng, Yao Li, Hui Ding y Yan-ming Fang. "Spatial distributions of intra-community tree species under topographically variable conditions". Journal of Mountain Science 20, n.º 2 (febrero de 2023): 391–402. http://dx.doi.org/10.1007/s11629-022-7642-9.

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45

Sheidai, Masoud, Mona Naji, Zahra Noormohammadi, Maryam Nouroozi y Somayeh Ghasemzadeh-Baraki. "Contemporary inter-specific hybridization between Cirsium aduncum and C. haussknechtii (Asteraceae): Evidence from molecular and morphological data". Genetika 48, n.º 2 (2016): 497–514. http://dx.doi.org/10.2298/gensr1602497s.

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Cirsium aduncum Fisch. & C.A.Mey. Ex DC. and C. haussknechtii Boiss., (Asteraceae) are important medicinal plant species that grow in different geographical regions of Iran. We had no knowledge about population genetic structure, intra-specific and inter-specific gene flow and the presence of hybrid zone for this two species in Iran. Therefore, in order to provide data for conservation of these two medicinally important species, the population genetic analysis and morphometric studies were performed in 18 geographical populations of these species. ANOVA and MDS analyses revealed significant morphological difference among the studied populations in either species, while MDS plot showed morphological overlap in plants of these two species. AMOVA test revealed significant genetic difference among the studied populations. Mantel test showed positive significant correlation between genetic and geographical distances and the occurrence of isolation by distance. Population assignment test and STRUCTURE plot of genetic data revealed inter-specific introgression between these species.

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46

Affonso, PRAM y PM Galetti Jr. "Genetic diversity of three ornamental reef fishes (Families Pomacanthidae and Chaetodontidae) from the Brazilian coast". Brazilian Journal of Biology 67, n.º 4 suppl (diciembre de 2007): 925–33. http://dx.doi.org/10.1590/s1519-69842007000500017.

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Reef fishes of the families Pomacanthidae (angelfish) and Chaetodontidae (butterflyfish) are popular ornamental species, intensively harvested for the aquarium trade. The impacts of such activity on intra-specific diversity and reef ecosystems are still poorly understood in the south Atlantic. In the present work, a fine-scale genetic analysis using RAPD markers was performed in distinct samples of the queen angelfish (Holacanthus ciliaris), French angelfish (Pomacanthus paru), and banded butterflyfish (Chaetodon striatus) along the Brazilian coast. Most of the genetic variation in the three species was related to intra-population diversity. However, AMOVA results demonstrated that H. ciliaris presents a subtle population structure (sigmast = 0.132, P = 0.003), while P. paru and C. striatus present low genetic differentiation, especially remarkable in the latter (sigmast = 0.090, P = 0.001 and sigmast = 0.041, P = 0.028, respectively). Gene flow (Nm) was also higher in C. striatus than in the angelfish species. The reported patterns of genetic differentiation contrast with the similar pelagic stage of the selected species, suggesting that larval dispersal per se is a poor predictor of population structure in these reef fishes. Ecological features coupled with biogeographic history and distinct local selective pressures might play a major role on the genetic composition of each species. Although preliminary, the present results provide a baseline for monitoring the genetic variability in these reef species. These differences in the genetic structure among co-occurring species should be taken into consideration for the conservation of eventual evolutionary units along the Brazilian Province.

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Fagundes, Valéria. "Conservation genetics of the muriqui: past, present and future". Neotropical Primates 13, Supplement (1 de diciembre de 2005): 85–91. http://dx.doi.org/10.62015/np.2005.v13.627.

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Our understanding of the genetics of the muriqui have increased in recent decades. In the mid 1980’s the first data was obtained from polymorphisms of allozymes of 10 individuals of B. hypoxanthus (northern muriqui) from Minas Gerais, and two individuals of B. arachnoides (southern muriqui) from São Paulo. All specimens were considered to be of a single species. The DNA was extracted from blood samples, which required capture and anesthesia of animals. We can now extract mitochondrial DNA from feces samples. Analyzing more than 120 individuals of the northern muriqui from two populations, we are now able make inferences about genetic variability, population distinctiveness as well as intra- and interpopulation gene flow. DNA sampling through feces is reliable, efficient, and economic, and does not risk the physical integrity of the animals, and furnishes enough DNA that is easily reproducible for PCR amplification. Using this method it is possible to sample a greater number of individuals in nature than would be possible if live capture were necessary. A muriqui feces and DNA bank has been set up, and currently has samples of 230 individuals from seven of the twelve known populations of northern muriqui. The samples resulted from field studies, but more coordinated and systematic efforts among fieldworkers at the different muriqui sites are needed to improve representation across populations and species. Future perspectives include the use of new genetic markers (nuclear and mitochondrial DNA) to identify parents, offspring, and closely related individuals in captive and wild populations; to define units for conservation and the gene flow between them; to quantify genetic variability in the populations; to assess the rate at which genetic variation has been lost over time; to estimate the degree of inbreeding in the population; and to understand better the genetic differentiation of the two species.

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Khan, Muhammad Khalil Ullah, Noor Muhammad, Nisar Uddin, Niaz Ali, Muhammad Umer y Shariat Ullah. "Genetic diversity in threatened plant species Alnus nitida (Spach.) Endel". Plant Science Today 7, n.º 3 (1 de julio de 2020): 314–18. http://dx.doi.org/10.14719/pst.2020.7.3.759.

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Alnus nitida (Spach) Endl. is an ethnobotanically important threatened plant species. The genetic diversity among the 50 different genotypes of Alnus nitida was carried out using sodium dodecyl sulfate poly acrylamide gel electrophoresis (SDS-PAGE) characterization. A considerable amount of genetic diversity (90%) was observed among the genotypes of A. nitida. The protein characterization was carried out on 12% gel electrophoresis. A total of 10 protein bands were detected in A. nitida genotypes. SDS-PAGE procedure is a useful method for the investigation of both genetic diversity and phylogenetic relationship. Especially, B-5 was monomorphic in A. nitida genotypes and was considered as species specific. All other bands/loci were polymorphic. These polymorphic bands displayed 12, 16, 72, 88, 2, 44, 84, 54 and 12 percent variation respectively. In the present examination, the high intra-specific diversity was observed representing SDS-PAGE is a powerful tool for determining the genetically diverse germplasms in A. nitida. The results obtained by this study could be helpful in the identification and selection of desired genotypes of Alnus nitida for conservation programmes in future. Today, there is still a need to assess genetic variation and protect genetic resources, especially of wild species for prospective benefits in plant conservation programmes.

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Buchenrieder, Gertrud y Roland Azibo Balgah. "Sustaining livelihoods around community forests. What is the potential contribution of wildlife domestication?" Journal of Modern African Studies 51, n.º 1 (25 de febrero de 2013): 57–84. http://dx.doi.org/10.1017/s0022278x12000596.

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ABSTRACTCommunity forest management is often advanced as a remedy for failing top-down approaches to nature conservation. Contingent on the property rights theory, it assumes that local participation in natural resource management results in sustainable structures. There is, however, insufficient empirical evidence on the intra-community dynamics – especially when households have unequal access to the local institutions managing the natural resource. This paper looks at the socio-cultural, economic and institutional situation of households with and without access to management institutions in communities around the Kilum-Ijim Mountain Forest in Cameroon and analyses whether livelihood differences are associated with variations in management patterns. The analysis reveals differences by household type and a mixed picture of the evolution of species in the community forests over time, questioning the role of the community in natural resource conservation. Furthermore, the paper discusses the potentials of wildlife domestication for livelihoods and conservation in forest communities. The results are important in the light of ongoing conservation efforts in natural resource hot-spots in sub-Saharan Africa.

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Ings, Kate y Daniela Denk. "Avian Malaria in Penguins: Diagnostics and Future Direction in the Context of Climate Change". Animals 12, n.º 5 (28 de febrero de 2022): 600. http://dx.doi.org/10.3390/ani12050600.

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Avian malaria is caused by infection with haemoprotozoa of the genus Plasmodium. Infection is endemic in large parts of the world and is typically subclinical in birds that are native to these regions. Several penguin species have evolved in non-endemic regions without the selective pressure that these parasites exert and are highly susceptible to infection when transplanted to endemic regions, for example, in the context of zoological collections or rehabilitation centers. Avian malaria in penguins typically causes acute mortality without premonitory signs, or less commonly, nonspecific signs of morbidity, followed by mortality. Additionally, infection is reported in wild penguins, though the significance of these infections remains equivocal. As global temperatures continue to increase, avian malaria is likely to pose a continued and further threat to conservation efforts in captive environments. Intra vitam diagnosis currently relies on the evaluation of blood smears and molecular methods. The former is unreliable in penguins, as the acute clinical course typically does not allow the development of parasitemia. This absence of parasitemia also makes speciation challenging. Current molecular methods typically target the Cytochrome B or 18s subunit and have proven variably sensitive and specific. Reliable intra vitam diagnosis of avian malaria and further information about the causative agents at a species level would be very valuable in understanding the epidemiology and likely future course of avian malaria infection in penguins, and in particular, the implications avian malaria may have for conservation efforts. This paper provides an overview of malaria in penguins, discusses its changing impact on management and conservation, offers a summary of current diagnostics, and suggests future direction for the development of diagnostic tests. The latter will be key in understanding and managing this disease.

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