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1.
Environ Pollut ; 361: 124920, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39251122

RESUMEN

Per- and polyfluoroalkyl substances (PFASs) are severely polluted in aquatic environments and can harm aquatic organisms. Due to the limitation of conducting toxicity experiments directly on threatened and endangered (T&E) species, their toxicity data is scarce, hindering accurate risk assessments. The development of computational toxicology makes it possible to assess the risk of pollutants to T&E fishes. This study innovatively combined machine learning models, including random forest (RF), artificial neural network (ANN), and XGBoost, and the QSAR-ICE model to predict chronic developmental toxicity data of PFASs to T&E fishes. Among these, the XGBoost model exhibited superior performance, with R2 of 0.95 and 0.81 for the training and testing sets, respectively. Internal and external validation further confirmed that the XGBoost model is robust and reliable. Subsequently, it was used to predict chronic developmental toxicity data for seven priority PFASs to T&E fishes in the Yangtze River. Acipenseridae fishes (e.g., Acipenser dabryanus and Acipenser sinensis) showed high sensitivity to PFASs, possibly due to their unique lifestyle and physiological characteristics. Based on these data, the predicted no-effect concentration (PNEC) of individual PFASs was calculated, and the risk for T&E fishes in the Yangtze River was assessed. The results indicated that the risk of PFASs to T&E fishes is low (3.85 × 10-9∼8.20 × 10-4), with perfluorohexanoic acid (PFHxA) and perfluorooctanoic acid (PFOA) as the high-risk pollutants. The risk in the middle and lower reaches of the river is higher than in the upper reaches. This study provides a new approach for obtaining chronic toxicity data and conducting risk assessments for T&E species, advancing the protection of T&E species worldwide.

2.
Plants (Basel) ; 13(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39273892

RESUMEN

Cryopreservation, storing biological material in liquid nitrogen (LN, -196 °C), offers a valuable option for the long-term conservation of non-orthodox seeds and vegetatively propagated species in the sector of agrobiodiversity and wild flora. Although the large-scale cryobanking of germplasm collections has been increasing worldwide, the wide application of cryopreservation protocols in wild flora is hampered by difficulties in vitro propagation and a lack of universal cryopreservation protocols, among others. This study established a systematic approach to developing an in vitro culture and droplet-vitrification cryopreservation procedure for shoot tips of Scrophularia kakudensis. The standard procedure includes a two-step preculture with 10% sucrose for 31 h and with 17.5% sucrose for 16 h, osmoprotection with loading solution C4-35% (17.5% glycerol + 17.5% sucrose, w/v) for 30 min, cryoprotection with A3-80% (33.3% glycerol + 13.3% dimethyl sulfoxide + 13.3% ethylene glycol + 20.1% sucrose, w/v) at 0 °C for 60 min, and cooling and rewarming using aluminum foil strips. After unloading, a three-step regrowth procedure starting with an ammonium-free medium with growth regulators was essential for developing normal plantlets from cryopreserved shoot tips. Liquid overlay on the gelled medium two weeks after inoculation resulted in vigorous growth during subcultures. Moreover, liquid overlay increased LN regeneration by up to 80%, i.e., 23% higher than no liquid overlay.

3.
Animals (Basel) ; 14(17)2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39272316

RESUMEN

Freshwater mussels (order: Unionida) are highly imperiled globally and are increasingly the focus of captive propagation efforts to protect and restore wild populations. The Upper Tennessee River Basin (UTRB) in Virginia is a freshwater biodiversity hotspot hosting at least 45 of North America's ~300 species of freshwater mussels, including 21 threatened and endangered species listed under the U.S. Endangered Species Act. Recent studies have documented that viruses and other microbes have contributed to freshwater mussel population declines in the UTRB. We conducted a multi-year longitudinal study of captive-reared hatchery mussels released to restoration sites throughout the UTRB to evaluate their viromes and compare them to captive hatchery environments. We documented 681 viruses from 27 families. The hatchery mussels had significantly less viruses than those deployed to wild sites, with only 20 viruses unique to the hatchery mussels. After the hatchery mussels were released into the wild, their number of viruses initially spiked and then increased steadily over time, with 451 viruses in total unique to the mussels in the wild. We found Clinch densovirus 1 (CDNV-1), a virus previously associated with mass mortality events in the Clinch River, in all samples, but the wild site mussels consistently had significantly higher CDNV-1 levels than those held in the hatchery. Our data document substantial differences between the viruses in the mussels in the hatchery and wild environments and rapid virome shifts after the mussels are released to the wild sites. These findings indicate that mussel release programs might benefit from acclimatization periods or other measures to mitigate the potential negative effects of rapid exposure to infectious agents found in natural environments.

4.
Animals (Basel) ; 14(17)2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39272377

RESUMEN

The Formosan pangolin (Manis pentadactyla pentadactyla) is an endemic animal of Taiwan. Due to their reduced population and behavior, very little is known about this enigmatic species. To unravel male pangolin reproduction, in the present study, we built a complete genomic database of the male Formosan pangolin reproductive tract and revealed highly expressing genes as well as critical signaling pathways and their associated biological processes in both the testis and the epididymis. Moreover, we evaluated the domestic cat (Felis catus) as a potential model species for male pangolin reproduction by comparing their testicular transcriptomes. We demonstrated a clear tissue-specific gene expression supporting the unique biological signature of each reproductive tissue and identified critical genes of the different reproductive organs. Pathway enrichment analysis revealed unique pathways in the testis as well as a clear epididymal transition. Furthermore, domestic cats, despite being the closest domestic species to pangolin, demonstrated their unfitness as a male reproduction model species as clear differences in spermatid differentiation and metabolism were observed. These results enable a better understanding of male pangolin reproduction characteristics and may inspire improvements in in Formosan pangolin conservation strategies.

5.
G3 (Bethesda) ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39268723

RESUMEN

Advancements in genome sequencing technology have brought unprecedented accessibility of high-throughput sequencing to species of conservation interest. The potential knowledge gained from application of these techniques is maximized by availability of high-quality, annotated reference genomes for endangered species. However, these vital resources are often lacking for endangered minnows of North America (Cypriniformes: Leuciscidae). One such endangered species, Colorado pikeminnow (Ptychocheilus lucius) is the largest North American minnow and the top-level native aquatic predator in the Colorado River Basin of the southwestern United States and northwestern Mexico. Over the past century Colorado pikeminnow has suffered habitat loss and population declines due to anthropogenic habitat modifications and invasive species introductions. The lack of genetic resources for Colorado pikeminnow has hindered conservation genomic study of this unique organism. This study seeks to remedy this issue by presenting a high-quality reference genome for Colorado pikeminnow developed from Pacific Biosciences HiFi sequencing and Hi-C scaffolding. The final assembly was a 1.1 Gb genome comprised of 305 contigs including 25 chromosome-sized scaffolds. Measures of quality, contiguity, and completeness met or exceeded those observed for Danio rerio (Danionidae) and two other Colorado River Basin leuciscids (Meda fulgida and Tiaroga cobitis). Comparative genomic analyses identified enrichment of gene families for growth, development, immune activity, and gene transcription; all of which are important for a large-bodied piscivorous fish living in a dynamic environment. This reference genome will provide a basis for important conservation genomic study of Colorado pikeminnow and help efforts to better understand the evolution of desert fishes.

6.
FEBS Open Bio ; 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39275913

RESUMEN

Recent advances in DNA sequencing technology have dramatically improved our understanding of the gut microbiota of various animal species. However, research on the gut microbiota of birds lags behind that of many other vertebrates, and information about the gut microbiota of wild birds such as migratory waterfowl is particularly lacking. Because the ecology of migratory waterfowl (e.g., lifestyle, diet, physiological characteristics) differs from that of other birds, the gut microbiota of migratory waterfowl likely also differs, but much is still unknown. The hooded crane (Grus monacha) is an important representative migratory waterbird species and is listed as endangered on the International Union for Conservation of Nature and Natural Resources Red List of Threatened Species. In this study, we analyzed the bacterial and viral microbiota in the gut of hooded cranes by using deep sequencing data from fecal samples of hooded cranes that winter on the Izumi plain in Japan, and found that Cetobacterium, Clupeiformes, and Pbunavirus were clearly present in the fecal samples of hooded cranes. These findings advance our understanding of the ecology of hooded cranes.

7.
Conserv Biol ; : e14370, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225270

RESUMEN

Expert judgment underpins assessment of threatened ecosystems. However, experts are often narrowly defined, and variability in their judgments may be substantial. Models built from structured elicitation with large diverse expert panels can contribute to more consistent and transparent decision-making. We conducted a structured elicitation under a broad definition of expertise to examine variation in judgments of ecosystem viability and collapse in a critically endangered ecosystem. We explored whether variation in judgments among 83 experts was related to affiliation and management expertise and assessed performance of an average model based on common ecosystem indicators. There were systematic differences among individuals, much of which were not explained by affiliation or expertise. However, of the individuals affiliated with government, those in conservation and environmental departments were more likely to determine a patch was viable than those in agriculture and rural land management. Classification errors from an average model, in which all individuals were weighted equally, were highest among government agriculture experts (27%) and lowest among government conservation experts (12%). Differences were mostly cases in which the average model predicted a patch was viable but the individual thought it was not. These differences arose primarily for areas that were grazed or cleared of mature trees. These areas are often the target of restoration, but they are also valuable for agriculture. These results highlight the potential for conflicting advice and disagreement about policies and actions for conserving and restoring threatened ecosystems. Although adoption of an average model can improve consistency of ecosystem assessment, it can fail to capture and convey diverse opinions held by experts. Structured elicitation and models of ecosystem viability play an important role in providing data-driven evidence of where differences arise among experts to support engagement and discussion among stakeholders and decision makers and to improve the management of threatened ecosystems.


Análisis de los modelos de opiniones de expertos para informar la evaluación de la viabilidad y el colapso ambiental Resumen La evaluación de los ecosistemas amenazados se basa en la opinión de los expertos. Sin embargo, la definición de experto suele ser limitada y la variabilidad de sus juicios puede ser considerable. Los modelos elaborados a partir de consultas estructuradas con grupos de expertos amplios y diversos pueden contribuir a una toma de decisiones más coherente y transparente. Realizamos una consulta estructurada con una definición amplia de experto para analizar la variación en los juicios sobre la viabilidad y el colapso de un ecosistema en peligro crítico. Exploramos si la variación en los juicios entre 83 expertos estaba relacionada con la afiliación y la experiencia en gestión y evaluamos el rendimiento de un modelo medio basado en indicadores comunes del ecosistema. Observamos diferencias sistemáticas entre los expertos, gran parte de las cuales no se explicaban por la afiliación o la experiencia. Sin embargo, entre los expertos vinculados a la administración pública, los de los departamentos de conservación y medio ambiente tenían más probabilidades de determinar que una parcela era viable que los de agricultura y gestión de tierras rurales. Los errores de clasificación de un modelo medio con todos los individuos ponderados por igual, fueron mayores entre los expertos gubernamentales en agricultura (27%) y menores entre los expertos gubernamentales en conservación (12%). En la mayoría de los casos, las diferencias se debían a que el modelo medio predecía que una parcela era viable, pero el individuo pensaba que no lo era. Estas diferencias surgieron sobre todo en zonas que habían sido pastoreadas o con una tala total de árboles maduros. Estas zonas suelen ser objeto de restauración, pero también son valiosas para la agricultura. Estos resultados ponen de manifiesto la posibilidad de que se produzcan consejos contradictorios y desacuerdos sobre las políticas y acciones de conservación y restauración de los ecosistemas pastoreados y forestales. Si bien la adopción de un modelo medio puede mejorar la coherencia de la evaluación de los ecosistemas, también puede fallar a la hora de captar y transmitir las diversas opiniones de los expertos. Las consultas estructuradas y los modelos de viabilidad de los ecosistemas desempeñan un papel importante a la hora de aportar pruebas basadas en datos de dónde surgen las diferencias entre los expertos para apoyar el compromiso y el debate entre las partes interesadas y los responsables de la toma de decisiones, así como para mejorar la gestión de los ecosistemas amenazados.

8.
Zoo Biol ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39228291

RESUMEN

Maintaining a diverse gene pool is important in the captive management of zoo populations, especially in endangered species such as the pink pigeon (Nesoenas mayeri). However, due to the limited number of breeding individuals and relaxed natural selection, the loss of variation and accumulation of harmful variants is inevitable. Inbreeding results in a loss of fitness (i.e., inbreeding depression), principally because related parents are more likely to transmit a copy of the same recessive deleterious genetic variant to their offspring. Genomics-informed captive breeding can manage harmful variants by artificial selection, reducing the genetic load by avoiding the inheritance of two copies of the same harmful variant. To explain this concept in an interactive way to zoo visitors, we developed a sonification game to represent the fitness impacts of harmful variants by detuning notes in a familiar musical melody (i.e., Beethoven's Für Elise). Conceptually, zoo visitors play a game aiming to create the most optimal pink pigeon offspring in terms of inbreeding depression. They select virtual crosses between pink pigeon individuals and listen for the detuning of the melody, which represents the realised load of the resultant offspring. Here we present the sonification algorithm and the results of an online survey to see whether participants could identify the most and least optimal offspring from three potential pink pigeon offspring. Of our 98 respondents, 85 (86.7%) correctly identified the least optimal offspring, 73 (74.5%) correctly identified the most optimal, and 62 (63.3%) identified both the most and least optimal offspring using only the sonification.

9.
Conserv Biol ; 38(5): e14358, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39248733

RESUMEN

Monitoring wildlife trade dynamics is an important initial step for conservation action and demand reduction campaigns to reduce illegal wildlife trade. Studies often rely on one data source to assess a species' trade, such as seizures or the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) trade data. Each database provides useful information but is often incomplete. Combining information from multiple sources helps provide a more complete understanding of trade. A recent rapid increase in demand for helmeted hornbill (Rhinoplax vigil) casques (a brightly colored, solid keratinous rostrum) led to its uplisting to critically endangered on the International Union for Conservation of Nature Red List in 2015. However, there is little current information on what factors influence trade trends and what current levels of demand are. We combined data from CITES, seizure records, and previously underused, yet abundant, art and antique auction data to examine the global trade in helmeted hornbill casque products (HHPs). Three decades of auction data revealed that 1027 individual HHPs had been auctioned since 1992; total auction sales were over US$3 million from 1992 to 2021. The number of HHPs auctioned was greatest from 2011 to 2014, just after the global art boom (2009-2011), followed by a decline in volume and price. The auction data also revealed 2 possible markets for HHPs: true antique and speculative, defined by era, price, and trade patterns. Trends in illegal trade matched those of the auction market, but legal trade remained consistently low. Combining data sources from legal, illegal, and gray markets provided an overview of the dynamics of illegal trade in an endangered species. This approach can be applied to other wildlife markets to provide a more complete understanding of trade and demand at the market level to inform future demand reduction campaigns.


Análisis del comercio ornamental legal, ilegal y gris del cálao con casco, especie en peligro crítico Resumen El monitoreo de la dinámica del comercio de especies silvestres es un paso inicial importante para las acciones de conservación y las campañas de reducción de la demanda destinadas a reducir el comercio ilegal de especies silvestres. Los estudios suelen basarse en una sola fuente de datos para evaluar el comercio de una especie, como las incautaciones o los datos comerciales de la Convención sobre el Comercio Internacional de Especies Amenazadas de Fauna y Flora Silvestres (CITES). Cada base de datos proporciona información útil, pero a menudo incompleta. La combinación de información procedente de varias fuentes ayuda a comprender mejor el comercio. Un reciente y rápido aumento de la demanda de cascos (un casquete queratinoso, sólido y de colores brillantes) de cálao con casco (Rhinoplax vigil) hizo que en 2015 se incluyera en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza como especie en peligro crítico. Sin embargo, existe poca información actual sobre los factores que influyen en las tendencias del comercio y cuáles son los niveles actuales de demanda. Combinamos datos de CITES, registros de incautaciones y datos de subastas de arte y antigüedades previamente poco utilizados, aunque abundantes, para examinar el comercio mundial de productos de casquetes de cálao con casco (CCC). Tres décadas de datos de subastas revelaron que se habían subastado 1,027 CCC individuales desde 1992; las ventas totales en subasta superaron los tres millones de dólares entre 1992 y 2021. El número de CCC subastados fue mayor entre 2011 y 2014, justo después del boom del arte (2009­2011), seguido de un descenso en volumen y precio. Los datos de las subastas también revelaron dos posibles mercados para los CCC: el de las verdaderas antigüedades y el especulativo, definidos por la época, el precio y los patrones de comercio. Las tendencias del comercio ilegal coincidieron con las del mercado de subastas, pero el comercio legal se mantuvo bajo con constancia. Con la combinación de fuentes de datos de mercados legales, ilegales y grises, nuestros datos proporcionaron una visión general de la dinámica del comercio ilegal de una especie amenazada. Este enfoque puede aplicarse a otros mercados de especies silvestres para obtener un conocimiento más completo del comercio y la demanda a nivel de mercado que sirva de base a futuras campañas de reducción de la demanda.


Asunto(s)
Comercio , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Especies en Peligro de Extinción/legislación & jurisprudencia , Conservación de los Recursos Naturales/legislación & jurisprudencia , Animales , Comercio/legislación & jurisprudencia , Crimen/prevención & control
10.
Conserv Biol ; 38(5): e14339, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39248763

RESUMEN

Environmental regulations restricting the use of a natural resource or species often have unintended consequences. One example is prohibitions on the international trade in culturally important endangered wildlife. Trade restrictions may artificially increase scarcity and, consequently, value. In China, international trade restrictions may trigger bouts of speculative investment that have the opposite effect of the restrictions' intent. We examined how China's speculative economy and cultural history have together led to unintended consequences when regulating wildlife trade. In China, wildlife markets occupy a legal gray area that can make regulations ineffectual or even counterproductive. In extreme cases, prohibiting trade can provoke market booms. Further unintended consequences include potential cultural backlash. In China and across the Global South, international trade restrictions are sometimes considered a continuation of a longstanding history of Western intervention and thus may not be enforced as strongly or may generate resentment. This pushback has contributed to rising calls to decolonialize conservation and may lead to growing alliances between China and other Global South countries when negotiating international wildlife trade restrictions in the future.


Especulación financiera y herencia cultural en los mercados de fauna de China Resumen Las regulaciones ambientales que restringen el uso de un recurso natural o una especie suelen tener consecuencias accidentales. Un ejemplo son las prohibiciones para el mercado internacional de fauna en peligro con importancia cultural. Las restricciones pueden incrementar de manera artificial la escasez y, como consecuencia, el valor. En China, las restricciones internacionales del mercado pueden detonar episodios de inversión especulativa que tienen el efecto opuesto a lo que se pretende con las restricciones. Analizamos cómo la economía especulativa y la historia cultural de China han, en conjunto, derivado en consecuencias accidentales cuando se regula el mercado de fauna. En este país, los mercados de fauna ocupan un área legal gris que puede volver ineficaces a las regulaciones o incluso contraproducentes. En casos extremos, prohibir el mercado puede provocar un auge de este. Otra consecuencia accidental es el potencial rechazo cultural. En China y en todo el Sur Global, algunas veces se consideran las restricciones del mercado internacional como una continuación de la historia de intervenciones occidentales y por lo tanto puede que no se apliquen con tanta fuerza o que generen resentimiento. Esta resistencia ha contribuido al incremento de llamados para descolonizar la conservación y podría llevar al aumento de alianzas entre China y otros países del Sur Global cuando se negocien restricciones para el mercado internacional de fauna en el futuro.


Asunto(s)
Animales Salvajes , Comercio , Conservación de los Recursos Naturales , China , Conservación de los Recursos Naturales/legislación & jurisprudencia , Conservación de los Recursos Naturales/economía , Animales , Especies en Peligro de Extinción , Cultura
11.
Heliyon ; 10(16): e35875, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39247277

RESUMEN

Assessing the degree of genetic diversity and differentiation of rare or endangered endemic species is essential to evaluate the conservation status of populations and successively implement appropriate conservation strategies. We investigated the population structure of Salvia ceratophylloides Ard., a scapose hemicryptophyte endemic to Calabria (southern Italy), both to answer questions about its genetic structure and to determine whether the actual population size has undergone significant demographic changes in the near past. The data obtained from the census showed that the populations are characterised by a greater number of adult individuals than juveniles and are on declining. The genetic analysis carried out on 99 individuals from four populations of the species under study, shows a mean expected heterozygosity value of 0.50 and an overall differentiation value of 0.083. The population structure shows that the four studied populations are distinct genetic units, genetically linked to four different ancestral gene pools. Bayesian analysis based on ABC models indicates that the present populations underwent a significant reduction in size in the past. This corresponds to the demographic decline at the end of the 19th century, which according to the literature, was due to the strong anthropic pressure (agriculture, grazing, fire and plantations) of Reggio Calabria suburbs. We can therefore conclude that populations are not affected by inbreeding and low genetic diversity and that there is no immediate danger of genetic erosion, and that the problems associated with population decline, past and present, are exclusively due to anthropogenic causes.

12.
Mol Ecol ; : e17533, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39262289

RESUMEN

Habitat fragmentation reduces gene flow, causing genetic differentiation and diversity loss in endangered species through genetic drift and inbreeding. However, the impact of habitat fragmentation on ectomycorrhizal (ECM) fungi remains unexplored, despite their critical roles in forest ecosystems. Here, we investigated the population genetic structure and the demographic history of Rhizopogon togasawarius, the ECM fungus specifically colonizing the host tree Pseudotsuga japonica, across its entire distribution range (>200 km). These two species are designated as endangered species on the IUCN Red List since they are found only in small, fragmented forests in Japan. We analysed 236 R. togasawarius individuals from five remaining populations across the Kii Peninsula and the Shikoku Island, separated by a sea channel. Simple sequence repeat analyses using 20 loci revealed strong genetic differentiation among populations (FST = 0.255), even significant in the nearest population pair separated by a distance of only 8 km (FST = 0.075), indicating extremely limited gene flow between populations. DIYABC-RF analyses implied that population divergence occurred approximately 6000 generations ago between the two regions, and nearly 1500 generations ago between the nearest populations within Shikoku Island, related to past climate events. Because of prolonged genetic isolation, significant inbreeding was confirmed in four of five populations, where effective population sizes became very small (Ne = 9.0-58.0). Although evaluation of extinction risks for microorganisms is challenging, our conservation genetic results indicated that habitat fragmentation increases extinction risk through population genetic mechanisms, and therefore should not be overlooked in biodiversity conservation efforts.

13.
Front Microbiol ; 15: 1420305, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39165571

RESUMEN

The gut microbiome plays important roles in metabolic and immune system related to the health of host. This study applied non-invasive sampling and 16S rDNA high-throughput sequencing to study the gut microbiota structure of red pandas (Ailurus fulgens) for the first time under different geographical latitudes in captivity. The results showed that the two predominant phyla Firmicutes (59.30%) and Proteobacteria (38.58%) constituted 97.88% of the total microbiota in all the fecal samples from north group (red pandas from Tianjin Zoo and Jinan Zoo) and south group (red pandas from Nanjing Hongshan Forest Zoo). The relative abundance of Cyanobacteria in north group was significantly higher than that in south group. At the genus level, Escherichia-Shigella (24.82%) and Clostridium_sensu_stricto_1 (23.00%) were common dominant genera. The relative abundance of norank_f__norank_o__Chloroplast, Terrisporobacter and Anaeroplasma from south group was significantly higher than that of north group. Alpha and Beta analysis consistently showed significant differences between north group and south group, however, the main functions of intestinal microbiota were basically the same, which play an important role in metabolic pathways, biosynthesis of secondary metabolites, microbial metabolism in different environments, and amino acid biosynthesis. The variations in gut microbiota between the northern and southern populations of the same species, both kept in captivity, which are primarily driven by significant differences in climate and diet. These findings provide a deeper understanding of the gut microbiota in red pandas and have important implications for their conservation, particularly in optimizing diet and environmental conditions in captivity.

14.
Plant Environ Interact ; 5(4): e70001, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39183980

RESUMEN

Functional traits are important in understanding how plants respond and adapt to their immediate environment. Parrotia subaequalis is a highly endangered arbor species found throughout eastern China, primarily inhabiting hillsides and valleys, yet, little is known about the variation in leaf traits across these environments. In the present study, we tested this by comparing leaf surface area, leaf weight, leaf length, leaf symmetry and leaf mass per unit area, as well as the relationship between leaf traits and environmental factors and the scaling relationship between leaf surface area versus leaf dry mass. We observed significant differences in leaf surface area, weight, and length among the population sites, and these variables were strongly affected by environmental factors, especially high mean annual temperatures in hillside habitats and high mean annual precipitation in valley habitats. The scaling exponents remained numerically variant among the 10 populations, with different slopes greater than 1.0, and the scaling exponents increased significantly with hillside habitats. These metrics correlated with soil thickness associated with different habitat types. The areal ratio (AR) values in all populations deviated from 1, indicating that the two lamina sides were asymmetrical. The standardized symmetry index (SI) values displayed significant variation, especially in leaves from hillside habitats with a high degree of asymmetry. Collectively, our findings demonstrated that leaf functional traits exhibit considerable variability in response to different environmental contexts and provide valuable reference data that could be useful for conserving this endangered species.

15.
Ecol Evol ; 14(8): e70227, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39193167

RESUMEN

The Pinna nobilis, a Mediterranean mollusc, has suffered population declines due to a massive mortality event associated with various factors including the parasite Haplosporidium pinnae. Some populations show resilience, possibly due to local environmental conditions. In this study, a molecular multiplex PCR method was developed using species-specific primers targeting Internal Transcribed Spacer (ITS) regions of P. nobilis and P. rudis, allowing accurate species identification and hybrid detection. Samples from Mediterranean areas were analysed, including putative hybrids and individuals from five other bivalve species. DNA was isolated, ITS regions were amplified and sequenced, and phylogenetic analyses confirmed species differentiation and primer specificity. The multiplex-PCR successfully identified P. nobilis, P. rudis, and their hybrids based on distinct amplicon patterns. This study highlights the value of molecular tools in species conservation, especially for monitoring and managing hybridization, supporting effective biodiversity conservation strategies.

16.
J Vet Diagn Invest ; : 10406387241267850, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39175363

RESUMEN

Rabbit hemorrhagic disease virus 2 (RHDV2; Caliciviridae, Lagovirus europaeus), the cause of a highly transmissible and fatal lagomorph disease, has spread rapidly through the western United States and Mexico, resulting in substantial mortality in domestic and wild rabbits. The disease was first detected in California in May 2020, prompting an interagency/zoo/academia/nonprofit team to implement emergency conservation actions to protect endangered riparian brush rabbits (Sylvilagus bachmani riparius) from RHDV2. Prior to vaccinating wild rabbits, we conducted a vaccine safety trial by giving a single SC dose of Filavac VHD K C+V (Filavie) vaccine to 19 adult wild riparian brush rabbits captured and temporarily held in captivity. Rabbits were monitored for adverse effects, and serum was collected before vaccination, and at 7-10, 14-20, and 60 d post-vaccination. Sera were tested using an ELISA to determine antibody response and timing of seroconversion. Reverse-transcription quantitative real-time PCR (RT-qPCR) was performed on rectal swabs to evaluate infection status. No adverse effects from the vaccine were observed. Before vaccination, 18 of 19 rabbits were seronegative, and RHDV2 was not detected by RT-qPCR on any rectal swabs. After vaccination, all rabbits developed an antibody response, with titers of 1:10-1:160. Seroconversion generally occurred at 7-10 d. The duration of antibody response was ≥60 d in 12 of 13 rabbits. Sixteen animals were released and 4 were recaptured several months later, offering a glimpse into longer duration immune response. Our study has informed vaccination strategies for this species and serves as a model for protecting other vulnerable lagomorphs against RHDV2.

17.
Mol Ecol Resour ; : e14009, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39152661

RESUMEN

More efficient methods for extensive biodiversity monitoring are required to support rapid measures to address the biodiversity crisis. While environmental DNA (eDNA) metabarcoding and quantitative PCR (qPCR) methods offer advantages over traditional monitoring approaches, their large-scale application is limited by the time and labour required for developing assays and/or for analysis. CRISPR (clustered regularly interspaced short palindromic repeats) diagnostic technologies (Dx) may overcome some of these limitations, but they have been used solely with species-specific primers, restricting their versatility for biodiversity monitoring. Here, we demonstrate the feasibility of designing species-specific CRISPR-Dx assays in silico within a short metabarcoding fragment using a general primer set, a methodology we term 'ampliscanning', for 18 of the 22 amphibian species in Switzerland. We sub-selected nine species, including three classified as regionally endangered, to test the methodology using eDNA sampled from ponds at nine sites. We compared the ampliscanning detections to data from traditional monitoring at these sites. Ampliscanning was successful at detecting target species with different prevalences across the landscape. With only one visit, we detected more species per site than three traditional monitoring visits (visual and acoustic detections by trained experts), in particular more elusive species and previously undocumented but expected populations. Ampliscanning detected 25 species/site combinations compared to 12 with traditional monitoring. Sensitivity analyses showed that larger numbers of field visits and PCR replicates are more important for reliable detection than many technical replicates at the CRISPR-Dx assay level. Given the reduced sampling and analysis effort, our results highlight the benefits of eDNA and CRISPR-Dx combined with universal primers for large-scale monitoring of multiple endangered species across landscapes to inform conservation measures.

18.
PhytoKeys ; 244: 271-283, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39086737

RESUMEN

A new variety of hornwort from northern Thailand, Phaeocerosperpusillusvar.scabrellus is described based on morphological characters and molecular phylogenetic analyses. In this study, phylogenetic analyses supported that the new variety is closely related to P.perpusillusvar.perpusillus. Morphologically, it is distinguished from the autonimic variety in nearly smooth spores under light microscope. A taxonomic description, illustrations, and light and scanning electron micrographs are provided. In addition, the new variety is assessed as Endangered (EN), demonstrating its rarity by being currently known from only three subpopulations.

19.
Evol Appl ; 17(8): e13765, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39091352

RESUMEN

Conservation and sustainable management of lineages providing non-timber forest products are imperative under the current global biodiversity loss. Most non-timber forest species, however, lack genomic studies that characterize their intraspecific variation and evolutionary history, which inform species' conservation practices. Contrary to many lineages in the Andean biodiversity hotspot that exhibit high diversification, the genus Parajubaea (Arecaceae) has only three species despite the genus' origin 22 million years ago. Two of the three palm species, P. torallyi and P. sunkha, are non-timber forest species endemic to the Andes of Bolivia and are listed as IUCN endangered. The third species, P. cocoides, is a vulnerable species with unknown wild populations. We investigated the evolutionary relationships of Parajubaea species and the genetic diversity and structure of wild Bolivian populations. Sequencing of five low-copy nuclear genes (3753 bp) challenged the hypothesis that P. cocoides is a cultigen that originated from the wild Bolivian species. We further obtained up to 15,134 de novo single-nucleotide polymorphism markers by genotyping-by-sequencing of 194 wild Parajubaea individuals. Our total DNA sequencing effort rejected the taxonomic separation of the two Bolivian species. As expected for narrow endemic species, we observed low genetic diversity, but no inbreeding signal. We found three genetic clusters shaped by geographic distance, which we use to propose three management units. Different percentages of missing genotypic data did not impact the genetic structure of populations. We use the management units to recommend in situ conservation by creating new protected areas, and ex situ conservation through seed collection.

20.
Animals (Basel) ; 14(15)2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39123714

RESUMEN

The Medog in southeastern Tibet is home to a diverse range of wild animals. However, research on these mammals' species directories, distribution, and conservation status remains insufficient, despite their crucial role in maintaining ecological balance. The study carried out a camera-trapping survey to assess mammal biodiversity and the significance of mammal protection in their natural habitats in Gedang, Medog. Future directions and application prospects of the study for wildlife conservation in the southeastern Tibetan mountains were also discussed. The survey, spanning from April 2023 to May 2024, with 19,754 camera trap days, revealed 25 mammalian species across five orders and 14 families. Among these, four classified as Endangered, five as Vulnerable, two as Near Threatened on the IUCN Red List, nine were categorized as Critically Endangered or Endangered on the Red List of China's Vertebrates, and seven were China's national first-class key protected wildlife. The order Carnivora exhibited the highest diversity, comprising 12 species. Furthermore, the study filled the knowledge gap regarding the underrepresentation of Gongshan muntjac Muntiacus gongshanensis in IUCN and provided new insights into the recorded coexistence of the Himalayan red panda Ailurus fulgens and Chinese red panda Ailurus styani along the Yarlung Zangbo River for the first time, and also documented new upper elevation limits for four large to medium-sized species. Regarding the relative abundance indices (RAI) captured by camera traps, the most prevalent species identified was the White-cheeked macaque Macaca leucogenys, followed by the Gongshan muntjac and Himalayan serow Capricornis thar. The monitoring also captured a number of domestic dogs and livestock, as well as human disturbances. These findings underscore the importance of conserving these mammals and emphasize the need for conservation efforts to protect their habitats and reduce human activities that threaten their survival, thereby maintaining the ecological balance of the region. Additionally, the research highlighted Gedang's significance to global conservation efforts for mammalian diversity, providing essential data for effective wildlife conservation strategies.

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