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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.
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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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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.
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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.
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Population genomics can reveal cryptic biological diversity that may impact fitness while simultaneously serving to delineate relevant conservation units. Here, we leverage the power of whole-genome resequencing for conservation by studying 433 individual lesser prairie-chicken (Tympanuchus pallidicinctus; LEPC, a federally endangered species of conservation concern in the United States) and greater prairie-chicken (Tympanuchus cupido; GRPC, a legally huntable species throughout much of its range). The genomic diversity of two formally recognized distinct population segments (DPSs) of LEPCs is similar, but they are genetically distinct. Neither DPS is depleted of its genomic diversity, neither is especially inbred, and temporal diversity is relatively stable in both conservation units. Interspecific differentiation between the two species was only slightly higher than that observed between LEPC DPSs, due largely to bidirectional introgression. The high resolution provided by our dataset identified a genomic continuum between the two species such that individuals sampled from the hybrid zone were imperfectly assigned to their presumptive species when considering only their physical characteristics. The admixture between the two species is reflected in the spectrum of individual ancestry coefficients, which has legal implications for the "take" of individuals under the Endangered Species Act. Overall, our data highlight the recurring dissonance between static policies and dynamic species boundaries that are increasingly obvious in the population genomic era.
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Freshwater bivalve mussels in the order Unionida are highly endangered ecosystem engineers with a parasitic lifecycle necessitating a fish host to metamorphose from larval glochidia to juvenile mussel. While many species are broadcast spawners and release a large number of glochidia into the water column, many other species have a variety of highly evolved lure mechanisms and mantle displays to attract hosts to ensure a more targeted infestation. Almost all lure mussels are found exclusively in North America, with only one European species (Unio crassus) occasionally displaying a host attraction behaviour referred to as larval spurting. Here, I present evidence that the depressed river mussel (Pseudanodonta complanata) exhibits mantle displays to attract fish to gravid mussels for a targeted infestation, the first description of mantle displays in Europe.
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The volcano rabbit (Romerolagus diazi) is a lagomorph endemic to the central mountains of the Trans-Mexican Volcanic Belt and is classified as threatened at extinction risk. It is a habitat specialist in bunchgrass communities. The annual wildfires that occur throughout its distribution range are a vulnerability factor for the species. However, the effects of wildfires on volcano rabbit populations are not fully understood. We evaluated the occupancy and change in the volcano rabbit relative abundance index in the burned bunchgrass communities of the Ajusco-Chichinautzin Mountain Range during an annual cycle of wildfire events. Additionally, we assessed the factors that favor and limit occupation and reoccupation by the volcano rabbit using the relative abundance index in burned plots as an indicator of these processes. The explanatory factors for the response of the volcano rabbit were its presence in the nearby unburned bunchgrasses, the height of three species of bunchgrass communities, the proportion of different types of vegetation cover within a 500 m radius around the burned plots, heterogeneity of the vegetation cover, and the extent of the wildfire. Statistical analyses indicated possible reoccupation in less than a year in burned bunchgrass communities adjacent to unburned bunchgrass communities with volcano rabbits. The relative abundance index of volcano rabbits was not favored when the maximum height of the Muhlenbergia macroura bunchgrass community was less than 0.77 m. When the vegetation around the burned plots was dominated by forest (cover >30% of the buffer) and the fire was extensive, the number of latrines decreased per month but increased when the bunchgrass and shrub cover was greater around the burned plots. While the statistical results are not conclusive, our findings indicate a direction for future projects, considering extensive monitoring to obtain a greater number of samples that contribute to consolidating the models presented.
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Ecosistema , Incendios Forestales , Animales , México , Lagomorpha , Conejos , PoaceaeRESUMEN
Prior to the arrival of Europeans in North America, forest and grasslands individually covered a 3rd of the conterminous United States; however, following the colonial and pioneer periods, respectively, these land cover categories were reduced to 70% and 50% of their original prominence. The dominant driving force for native land conversion was agriculture, which expanded exponentially from the Atlantic to the Pacific, comprising over half the total land area of America at its peak in 1950. However, farmland area has subsequently declined by 25%, so what has been driving native plant declines north of the 30th latitudinal parallel over the past 75 years? Analysis of recovery plans issued by the U.S. Fish and Wildlife Service indicates that of the over 900 plant species "listed" as threatened and endangered the primary driver of decline was invasive species, followed by habitat alteration, and development, which collectively accounted for 93.2% of the primary drivers for listed species. In Canada, these three drivers of decline were the primary drivers for 81% of listed species. Comparatively, herbicides were identified as the primary or secondary driver in 13 out of 1124 cases (1.2%). Given that agricultural land area is contracting in the U.S. and Canada, there appears to be a misconception that agrochemicals are the seminal cause of native plant decline. Here, we explore the individual contribution of drivers relative to the historical events of North America to provide context and perspective as well as focus and prioritize conservation efforts accordingly.
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Ecosistema , América del Norte , Agricultura , Plantas , Conservación de los Recursos Naturales , Especies Introducidas , CanadáRESUMEN
In 2019, there was an environmental catastrophe in Brazil, when more than 5000 tons of unknown origin crude oil invaded beaches and mangroves. Two years later, two monitoring areas were selected to study seahorses' offspring: Massangana River estuary (apparently healthy area) and Cocaia Island (affected area). Thirty-six reproductive events of Hippocampus reidi (Syngnathidae) couples from these two areas were monitored to analyze the offspring. At the apparently healthy area, no newborns with malformations were found. However, the offspring from Cocaia Island showed a mean of 19.73% (±5.23) malformations in newborns. It is argued that the toxic/teratogenic effects of polycyclic aromatic hydrocarbons have affected the population in two ways: directly through the induction of mutations in the germ cells of the species and through a drastic reduction of the population (bottleneck effect) whose density observed today recovered through consanguineous couplings, potentiating deleterious genotypes in the offspring. Environ Toxicol Chem 2024;43:1996-2004. © 2024 SETAC.
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Contaminación por Petróleo , Smegmamorpha , Contaminantes Químicos del Agua , Animales , Brasil , Contaminantes Químicos del Agua/toxicidad , Masculino , Femenino , Hidrocarburos Policíclicos Aromáticos/toxicidad , Monitoreo del AmbienteRESUMEN
Although conservation efforts have reduced threats, the endangered smalltooth sawfish, Pristis pectinata, is still at risk from anthropogenic effects such as entanglement in recreational and commercial fishing gear. From 2017 to 2021, data from field research and the public in Florida documented 176 individuals that were entangled, injured, or killed by debris or human interactions. While entanglements in fishing gear (e.g., trawls, fishing tackle) remain the most frequent threat, interactions with household items have increased. Since 2017, 30 sawfish were reported with encircling debris (e.g., monofilament loops, rubber bands, ball bungee cords) around anterior parts of their bodies. Ball bungee cords have emerged as a problem, likely related to the popularity of their use in securing boat lift canopy covers. Collectively, encircling items have interfered with eye, spiracle, gill, and mouth function. Continued outreach is a priority to address these pollutants, their sources (e.g., manufacturers), and their effects on recovery.
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Residuos , Animales , Humanos , Florida , Explotaciones Pesqueras , Conservación de los Recursos NaturalesRESUMEN
Anticoagulant rodenticides (ARs) are one of the most toxic groups of compounds currently used worldwide for rodent pest control. Toxic baits are often, directly or indirectly, ingested by non-target animals, resulting in secondary poisoning and frequently affecting apex predators. Their presence in many species of raptors is quite common, particularly scavenger species, with some of these acting as sentinels for the presence of these substances in the environment. However, there is less data on the presence of ARs in Bonelli's eagle, one of the most endangered eagle species in Spain and which is experiencing a negative population trend in Europe. This medium-sized eagle feeds predominantly on live species, and rarely consumes carrion. In this study, 17 carcasses of Bonelli's eagles from the Eastern Spain were necropsied. Both first and second generation ARs in their livers were analyzed by HPLC-MS-TOF revealing that all the eagles studied had been exposed to at least 5 ARs, out of a total of 10 ARs analyzed, with 7 being the highest number of ARs detected in a sample. Second generation ARs were the most prevalent, particularly bromadiolone and brodifacoum, with the highest concentrations in 94% of the cases. More than a third of the eagles presented a liver concentration of greater than 200 ng/g ARs, suggesting AR poisoning. The elevated presence of these compounds in Bonelli's eagles could be a new cause of mortality for this species or could explain other causes of death, such as the increased mortality in power lines, and should be taken into account for their conservation. At the same time, the presence of these compounds in the environment also represents a risk to public health, as the most frequent species in the diet of Bonelli's eagle (rabbits and partridges) are also hunted and consumed by hunters and their families.
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Anticoagulantes , Águilas , Especies en Peligro de Extinción , Rodenticidas , Animales , Rodenticidas/metabolismo , España , Agricultura , 4-Hidroxicumarinas/metabolismo , Monitoreo del AmbienteRESUMEN
Species identification of stony corals (Scleractinia), which are regulated under the Convention on International Trade in Endangered Species of Wild Fauna and Flora, is critical for effective control of harvest quotas, enforcement of trade regulations and species conservation in general. DNA barcoding has the potential to enhance species identification success, depending on the specific taxon concerned and genetic markers used. For Acropora, DNA barcoding, based on the mitochondrial putative control region (mtCR) and the nuclear PaxC intron (PaxC), has been commonly used for species identification and delimitation, but the reliability and robustness of these loci remain contentious. Therefore, we sought to verify the applicability of this approach. In this study, we obtained 127 Acropora colonies from the aquarium trade to test the effectiveness of barcoding mtCR and PaxC for species identification. We were able to recover sequences for both loci in over half of the samples (n = 68), while gene amplification and sequencing of mtCR (n = 125) outperformed PaxC (n = 70). Amongst the 68 samples with both loci recovered, just a single sample could be unambiguously identified to species. Preliminary identities, based on only one gene, were assigned for 40 and 65 samples with mtCR and PaxC, respectively. Further analyses of 110 complete mitochondrial genomes obtained from GenBank showed that, despite the full length of the sequences, only eight species were delimited, of which only three species were correspondingly monophyletic. Therefore, we conclude that the commonly used DNA barcoding markers for Acropora are ineffective for accurate species assignments due to limited variability in both markers and even across the entire mitochondrial genome. Therefore, we propose that barcoding markers should generally not be the only means for identifying corals.
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Prosthechea karwinskii is an orchid endemic to Mexico, threatened by the destruction of its habitat and the extraction of specimens to meet its demand for ornamental and religious use. Most of its populations, including the most locally abundant ones, are found in Oaxaca state. Variations in some floral traits have been observed in these populations. We implemented a morphometric analysis to assess their floral variation and identify the most significant characters in the morphological patterns of this orchid. Floral samples were collected from 17 populations of P. karwinskii in Oaxaca, as well as from specimens used as ornaments during Easter in an Oaxacan community (Zaachila), whose origin is unknown. Sampling of natural populations covered the environmental, geographic, and morphological variation of the species. We performed an analysis of variance (ANOVA), principal component analysis (PCA), canonical variate analysis (CVA), and cluster analysis, including 185 individuals and 45 variables (12 of them were discarded in the multivariate analyses due to high correlation). Characters of the column, lateral sepal, and labellum were most informative for the observed morphological patterns. Albarradas showed the greatest morphological differentiation, mainly due to the column. In general, individuals from the same locality tended to overlap more, especially the populations of Jaltianguis and Yahuiche, which were different from the geographically close population of Etla. Teposcolula presented the highest values in perianth characters, unlike Sola_Rancho Viejo. The specimens recovered from religious ornaments were morphologically more similar to those from Yanhuitlan and Etla. This morphometric analysis identified characters as potential taxonomic markers for P. karwinskii and related species, showing its potential to associate specimens of unknown origin with their probable geographical region. Our work encourages working on collaborative conservation strategies to ensure the long-term permanence of both the species and its traditional uses.
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Melastoma (Melastomataceae) includes ca. 100 species across tropical to subtropical regions of Asia and Oceania. The Bonin Islands harbor three endemic taxa: M. tetramerum, M. tetramerum var. pentapetalum, and M. candidum var. alessandrense. Of these, M. tetramerum is critically endangered and faces near extinction in the wild. This study investigates the phylogenetic relationships among these endemic Melastoma species in the Bonin Islands based on the whole chloroplast genome and nuclear SNPs. The results revealed that M. candidum var. alessandrense was placed in the clade of the widespread East Asian M. candidum and has a distinct evolutionary origin from the other two taxa. The population genomics analyses (heterozygosity, rates of deleterious mutations, and numbers and lengths of runs of homozygosity) indicated lower genetic diversity and more vulnerable genomes of endemic Melastoma, especially M. tetramerum var. pentapetalum. M. tetramerum var. pentapetalum is not a target of any protection programs, however, conservation plans might be required for this variety because M. tetramerum var. pentapetalum would have a more vulnerable genome than M. tetramerum, which faces near extinction in the wild. This information can facilitate the development of effective conservation strategies in a precautionary way that anticipates imminent threats to the survival of the species.
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Melastomataceae , Filogenia , Melastomataceae/genética , Polimorfismo de Nucleótido Simple , Especies en Peligro de Extinción , Genoma del Cloroplasto , Genómica/métodos , Islas , Variación Genética , Genoma de PlantaRESUMEN
The Seychelles magpie-robin's (SMR) five island populations exhibit some of the lowest recorded levels of genetic diversity among endangered birds, and high levels of inbreeding. These populations collapsed during the 20th century, and the species was listed as Critically Endangered in the IUCN Red List in 1994. An assisted translocation-for-recovery program initiated in the 1990s increased the number of mature individuals, resulting in its downlisting to Endangered in 2005. Here, we explore the temporal genomic erosion of the SMR based on a dataset of 201 re-sequenced whole genomes that span the past ~150 years. Our sample set includes individuals that predate the bottleneck by up to 100 years, as well as individuals from contemporary populations established during the species recovery program. Despite the SMR's recent demographic recovery, our data reveal a marked increase in both the genetic load and realized load in the extant populations when compared to the historical samples. Conservation management may have reduced the intensity of selection by increasing juvenile survival and relaxing intraspecific competition between individuals, resulting in the accumulation of loss-of-function mutations (i.e. severely deleterious variants) in the rapidly recovering population. In addition, we found a 3-fold decrease in genetic diversity between temporal samples. While the low genetic diversity in modern populations may limit the species' adaptability to future environmental changes, future conservation efforts (including IUCN assessments) may also need to assess the threats posed by their high genetic load. Our computer simulations highlight the value of translocations for genetic rescue and show how this could halt genomic erosion in threatened species such as the SMR.
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Climate change reduces snowpack, advances snowmelt phenology, drives summer warming, alters growing season precipitation regimes, and consequently modifies vegetation phenology in mountain systems. Elevational migrants track spatial variation in seasonal plant growth by moving between ranges at different elevations during spring, so climate-driven vegetation change may disrupt historic benefits of migration. Elevational migrants can furthermore cope with short-term environmental variability by undertaking brief vertical movements to refugia when sudden adverse conditions arise. We uncover drivers of fine-scale vertical movement variation during upland migration in an endangered alpine specialist, Sierra Nevada bighorn sheep (Ovis canadensis sierrae) using a 20-year study of GPS collar data collected from 311 unique individuals. We used integrated step-selection analysis to determine factors that promote vertical movements and drive selection of destinations following vertical movements. Our results reveal that relatively high temperatures consistently drive uphill movements, while precipitation likely drives downhill movements. Furthermore, bighorn select destinations at their peak annual biomass and maximal time since snowmelt. These results indicate that although Sierra Nevada bighorn sheep seek out foraging opportunities related to landscape phenology, they compensate for short-term environmental stressors by undertaking brief up- and downslope vertical movements. Migrants may therefore be impacted by future warming and increased storm frequency or intensity, with shifts in annual migration timing, and fine-scale vertical movement responses to environmental variability.
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Migración Animal , Cambio Climático , Estaciones del Año , Animales , Migración Animal/fisiología , Borrego Cimarrón/fisiología , Ecosistema , Ovinos/fisiologíaRESUMEN
Plant cell, tissue, and organ cultures (PCTOC) have been used as experimental systems in basic research, allowing gene function demonstration through gene overexpression or repression and investigating the processes involved in embryogenesis and organogenesis or those related to the potential production of secondary metabolites, among others. On the other hand, PCTOC has also been applied at the commercial level for the vegetative multiplication (micropropagation) of diverse plant species, mainly ornamentals but also horticultural crops such as potato or fruit and tree species, and to produce high-quality disease-free plants. Moreover, PCTOC protocols are important auxiliary systems in crop breeding crops to generate pure lines (homozygous) to produce hybrids for the obtention of polyploid plants with higher yields or better performance. PCTOC has been utilized to preserve and conserve the germplasm of different crops or threatened species. Plant genetic improvement through genetic engineering and genome editing has been only possible thanks to the establishment of efficient in vitro plant regeneration protocols. Different companies currently focus on commercializing plant secondary metabolites with interesting biological activities using in vitro PCTOC. The impact of omics on PCTOC is discussed.
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Células Vegetales , Técnicas de Cultivo de Tejidos , Técnicas de Cultivo de Célula/métodos , Productos Agrícolas/genética , Productos Agrícolas/crecimiento & desarrollo , Fitomejoramiento/métodos , Células Vegetales/metabolismo , Desarrollo de la Planta/genética , Plantas/genética , Plantas/metabolismo , Técnicas de Cultivo de Tejidos/métodosRESUMEN
Introduction: Integrating genetic data into conservation management decisions is a challenging task that requires strong partnerships between researchers and managers. Conservation in Latin America is of crucial relevance worldwide given the high biodiversity levels and the presence of hotspots in this region. Methods: We conducted a survey across Latin America to identify gaps and opportunities between genetic researchers and conservation managers. We aimed to better understand conservation managers' points of view and how genetic research could help conservation practitioners to achieve their goals, by implementing genetic assessments that could effectively inform conservation practices. We distributed an online survey via four regional collaborating organizations and 32 focal points based in 20 Latin American countries. The target respondents were conservation managers of species or areas in Latin America. Results: We collected a total of 468 answered questionnaires from 21 Latin American countries. Most respondents (44%) were from an academic or research institution while non-academics were mainly from non-governmental institutions (30%) and government agencies (25%). Most respondents (65%) have performed or used genetic assessments in their managed area or species, either alone, in partnership, contracting someone else or using published results. For the majority of this group, the genetic results were relevant to their conservation management goals, helping to inform management decisions. Respondents that had not performed genetic assessments (35%) were mainly from the non-academic group, and their main barriers were limited access to funds, genetic lab facilities, and trained personnel to design studies and conduct lab work. Discussion: From the findings, we describe the current situation and provide a general diagnosis of the conservation-genetics gap in Latin America. We describe the gender gap, academic-practitioner co-development of conservation questions and projects, and the nationality and residency of Latin American conservation managers in relation to the countries where they work. We discuss opportunities to co-create research questions and co-develop studies based on conservation practitioners' needs. We offer recommendations for overcoming barriers to integrate genetic information into conservation actions, and advance agendas that fit the needs and realities of the highly heterogeneous, biodiverse and challenging Latin American region.
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Enteric parasites can have wide-ranging effects throughout an ecosystem, often driving coevolutionary and ecological processes. Parasites have long been overlooked in conservation efforts because of the negative impact inflicted on their hosts; however, parasites make up a significant component of Earth's biodiversity and host conservation efforts need to be parasite inclusive. The Vancouver Island marmot (VIM), Marmota vancouverensis, is an endangered alpine rodent endemic to Vancouver Island, British Columbia, Canada. Captive-bred VIMs are released to augment the wild population, but their susceptibility to parasites is unknown. The objectives of this study were to describe the diversity, prevalence, severity, and temporal variation of VIM enteric parasites. Noninvasive fecal samples were collected from wild and captive marmots and analyzed using a modified McMaster fecal egg floatation technique to indicate parasite prevalence and relative mean abundance. We identified oocysts and ova from 3 parasite taxa including a protozoan coccidium not previously described in the VIM (prevalence 68%), an ascarid nematode Baylisascaris laevis (prevalence 82%), and an anoplocephalid cestode Diandrya vancouverensis (prevalence 8%). Depending on the species, comparisons revealed variation in parasite infection by sex, by colony, and between wild and captive VIMs, but not among age classes or by female reproductive status. Finally, captive VIMs displayed significant monthly variation in parasite prevalence and mean egg abundance, suggesting a seasonal influence on parasite egg shedding. This information is critically important for future research investigating the influences of these trends on the health, ecology, and conservation of VIMs and their parasites.
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Especies en Peligro de Extinción , Heces , Parasitosis Intestinales , Marmota , Dinámica Poblacional , Animales , Marmota/parasitología , Colombia Británica/epidemiología , Heces/parasitología , Femenino , Masculino , Prevalencia , Parasitosis Intestinales/veterinaria , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Enfermedades de los Roedores/parasitología , Enfermedades de los Roedores/epidemiología , Estaciones del Año , Animales Salvajes/parasitologíaRESUMEN
Spermatogonia cryopreservation can be a strategy for future conservation actions. The neotropical Siluriformes Pseudopimelodus mangurus was already classified as vulnerable on the Red List of Threatened Species. P. mangurus spermatogonial cells were isolated, assessed, and cryopreserved. Fragments of the testis were enzymatically dissociated, purified using Percoll density gradient, and submitted to differential plating. Fractionated cells were evaluated by microscopy, ddx4 (vasa) relative expression, and alkaline phosphatase activity. Cryopreservation was conducted using ethylene glycol, glycerol, dimethyl sulfoxide (DMSO), dimethylacetamide (DMA), and propanediol at 1 M, 1.5 M, and 2 M. Cell viability was evaluated and cell concentration was determined. Cell fractions from 20 % and 30 % Percoll gradient bands showed the highest concentrations of spermatogonia. The fraction mix showed 54 % purity and 93 % viability. After differential plating, 60 % purity and 92 % viability were obtained. Spermatogonial cells showed high alkaline phosphatase activity compared to spermatocytes and spermatids. The relative spermatogonial ddx4 expression from the Percoll density gradient was about twice as high as in samples from the testis and the differential plating. The increased ddx4 expression indicated the enrichment of spermatogonial cells by density gradient step and dead cells expressing ddx4 in differential plating, or ddx4 decreasing expression during cell culture. For this reason, cells from the Percoll gradient were chosen for cryopreservation. Propanediol at 1 M demonstrated the best condition for spermatogonial cell cryopreservation, presenting 98 % viability, while dimethylacetamide at 2 M represented the least favorable condition, with approximately 47 % viability. These findings are essential for P. mangurus spermatogonial cell cryopreservation, aiming to generate a spermatogonia cryobank for future conservation efforts.