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Bio-protocol Jun 2024Many studies on mosquito biology rely on laboratory-reared colonies, emphasizing the need for standardized protocols to investigate critical aspects such as disease...
Many studies on mosquito biology rely on laboratory-reared colonies, emphasizing the need for standardized protocols to investigate critical aspects such as disease biology, mosquito behavior, and vector control methods. While much knowledge is derived from anthropophilic species from genera like , and , there is a growing interest in studying mosquitoes that feed on non-human hosts. This interest stems from the desire to gain a deeper understanding of the evolution of diverse host range use and host specificity. However, there is currently a limited number of comprehensive protocols for studying such species. Considering this gap, we present a protocol for rearing , a mosquito species specialized in feeding on anuran amphibians by eavesdropping on host-emitted sound cues. Additionally, we provide instructions for successfully shipping live specimens to promote research on this species and similar ones. This protocol helps fill the current gap in comprehensive guidelines for rearing and maintaining colonies of anuran host-biting mosquitoes. It serves as a valuable resource for researchers seeking to establish colonies of mosquito species from the Uranotaeniini tribe. Ultimately, this protocol may facilitate research on the evolutionary ecology of Culicidae, as this family has recently been proposed to have originated from a frog-feeding ancestor. Key features • Rearing and maintenance of colonies of non-human host-biting mosquitoes that feed on frogs using host-emitted acoustic cues. • Provides shipping guidelines aimed to enhance the establishment of colonies by new research groups and specimen exchanges between labs.
PubMed: 38873019
DOI: 10.21769/BioProtoc.4996 -
Integrative Zoology Jun 2024Chytridiomycosis, an infectious skin disease caused by the chytrid fungi, Batrachochytrium dendrobatidis and B. salamandrivorans, poses a significant threat to amphibian...
Environmental factors and host sex influence the skin microbiota structure of Hong Kong newt (Paramesotriton hongkongensis) in a coldspot of chytridiomycosis in subtropical East Asia.
Chytridiomycosis, an infectious skin disease caused by the chytrid fungi, Batrachochytrium dendrobatidis and B. salamandrivorans, poses a significant threat to amphibian biodiversity worldwide. Antifungal bacteria found on the skin of chytrid-resistant amphibians could potentially provide defense against chytridiomycosis and lower mortality rates among resistant individuals. The Hong Kong newt (Paramesotriton hongkongensis) is native to East Asia, a region suspected to be the origin of chytrids, and has exhibited asymptomatic infection, suggesting a long-term coexistence with the chytrids. Therefore, the skin microbiota of this resistant species warrant investigation, along with other factors that can affect the microbiota. Among the 149 newts sampled in their natural habitats in Hong Kong, China, putative antifungal bacteria were found in all individuals. There were 314 amplicon sequence variants distributed over 25 genera of putative antifungal bacteria; abundant ones included Acinetobacter, Flavobacterium, and Novosphingobium spp. The skin microbiota compositions were strongly influenced by the inter-site geographical distances. Despite inter-site differences, we identified some core skin microbes across sites that could be vital to P. hongkongensis. The dominant cores included the family Comamonadaceae, family Chitinophagaceae, and class Betaproteobacteria. Moreover, habitat elevation and host sex also exhibited significant effects on skin microbiota compositions. The antifungal bacteria found on these newts offer an important resource for conservation against chytridiomycosis, such as developing probiotic treatments for susceptible species.
PubMed: 38872359
DOI: 10.1111/1749-4877.12855 -
Scientific Reports Jun 2024Decreases in body sizes of animals related to recent climate warming can affect population persistence and stability. However, direct observations of average sizes over...
Decreases in body sizes of animals related to recent climate warming can affect population persistence and stability. However, direct observations of average sizes over time and their interrelationships with underlying density-dependent and density-independent processes remain poorly understood owing to the lack of appropriate long-term datasets. We measured body size of two species common to headwater streams in coastal and Cascades ecoregions of the Pacific Northwest of North America over multiple decades, comparing old-growth and managed forests. We found consistent decreases in median length of Coastal Cutthroat Trout Oncorhynchus clarkii clarkii, but a coexisting species, the Coastal Giant Salamander Dicamptodon tenebrosus, appears to be more resilient to size changes over time. Based on observed trends, adult trout have decreased in length by 6-13% over the last 30 years. Length decreased more in larger compared to smaller animals, suggesting that these effects reflect changes in growth trajectories. Results from a model-selection approach that included hydroclimatic and biological information as covariates in one of our study ecoregions demonstrated that stream temperature alone did not explain observed length reductions. Rather, a combination of density-dependent (animal abundances) and local density-independent factors (temperature, habitat, and streamflow) explained observed patterns of size. Continued decreases in size could lead to trophic cascades, biodiversity loss, or in extreme cases, species extirpation. However, the intricate links between density-independent and density-dependent factors in controlling population-level processes in streams need further attention.
Topics: Animals; Urodela; Body Size; Trout; Ecosystem; Rivers; Climate Change; Temperature
PubMed: 38871823
DOI: 10.1038/s41598-024-64145-x -
Chemosphere Aug 2024Ciprofloxacin (CIP) and levofloxacin (LEV) are broad-spectrum antibiotics with potent antibacterial activity. Although many studies have shown that antibiotics can lead...
Ciprofloxacin (CIP) and levofloxacin (LEV) are broad-spectrum antibiotics with potent antibacterial activity. Although many studies have shown that antibiotics can lead to gut microbiota disruption, the effects of CIP and LEV on gut microbial colonization at the embryonic stage remain poorly characterized. Here, we evaluated the response of Bufo gargarizans embryos in terms of gut microbiota colonization, growth and developmental stages to CIP and LEV exposure. Embryos treated with 100 μg/L CIP and LEV exhibited significantly reduced diversity and richness of the gut microbiota, as well as altered community structure. Both CIP and LEV treatments resulted in an increase in the pathogenic bacteria Bosea and Aeromonas, and they appeared to be more resistant to CIP than LEV. Additionally, CIP exposure caused reduced total length and delayed the development in B. gargarizans embryos, while LEV increased the total length and promoted embryonic development. The present study revealed the adverse effects of CIP and LEV exposure on host gut microbiota, growth and development during the embryonic stage, and contributed new perspectives to the evaluation of early aquatic ecological risk under CIP and LEV exposure.
Topics: Ciprofloxacin; Gastrointestinal Microbiome; Animals; Levofloxacin; Anti-Bacterial Agents; Bufonidae; Water Pollutants, Chemical; Embryo, Nonmammalian; Bacteria
PubMed: 38871193
DOI: 10.1016/j.chemosphere.2024.142587 -
PloS One 2024The chytrid fungus Batrachochytrium salamandrivorans [Bsal] is causing declines in the amphibian populations. After a decade of mapping the pathogen in Europe, where it...
The chytrid fungus Batrachochytrium salamandrivorans [Bsal] is causing declines in the amphibian populations. After a decade of mapping the pathogen in Europe, where it is causing dramatic outbreaks, and North America, where its arrival would affect to the salamander's biodiversity hotspot, little is known about its current status in Asia, from presumably is native. Japan has several species considered as potential carriers, but no regulation is implemented against Bsal spreading. Previous Bsal known presence detected various cases on the Okinawa Island, southwestern Japan. Previous studies on its sister species, B. dendrobatidis presented a high genomic variation in this area and particularly on Cynops ensicauda. Here, we have done the largest monitoring to date in Japan on the Cynops genus, focusing on Okinawa Island and updating its distribution and providing more information to unravel the still unknown origin of Bsal. Interestingly, we have provided revealing facts about different detectability depending on the used molecular techniques and changes in its Japanese distribution. All in all, the Bsal presence in Japan, together with its low variability in the sequenced amplicons, and the lack of apparent mortalities, may indicate that this part of Asia has a high diversity of chytrids.
Topics: Animals; Japan; Urodela; Batrachochytrium; Phylogeny; Genetic Variation; Biodiversity; Chytridiomycota; Mycoses; East Asian People
PubMed: 38870137
DOI: 10.1371/journal.pone.0305228 -
Scientific Reports Jun 2024Microplastic pollution is a significant global environmental issue, and impacts span from individual organisms to the entire ecosystems. This study investigated the... (Comparative Study)
Comparative Study
Microplastic pollution is a significant global environmental issue, and impacts span from individual organisms to the entire ecosystems. This study investigated the properties of microplastics in amphibian larvae, shedding light on their environmental interactions and potential ecological consequences. We examined microplastics extracted from amphibian larvae of 10 taxa, sampled from sites experiencing different levels of human impact. Our findings revealed a predominance of blue microplastics and fibres, each comprising 53% of the total microplastics in amphibian larvae. Microplastic fibres were also notably longer than other morphological types of microplastics. Furthermore, we observed variations in the surface area of microplastics among different amphibian families. An interesting observation from our research is the apparent positive relationship between the size of amphibian larvae and the length of granular and flake-shaped microplastics. Conversely, we observed a negative relationship between the length of these microplastics and human environmental impact. These insights significantly contribute to the understanding of microplastic pollution in freshwater environments, highlighting its complexities beyond marine ecosystems. Our research emphasises the intricate relationships between microplastics and freshwater organisms, underscoring the need for comprehensive strategies to mitigate microplastic pollution.
Topics: Microplastics; Animals; Larva; Humans; Amphibians; Water Pollutants, Chemical; Ecosystem; Environmental Monitoring; Human Activities
PubMed: 38866833
DOI: 10.1038/s41598-024-61432-5 -
Reproductive Toxicology (Elmsford, N.Y.) Jun 2024Due to its endocrine disruptive activity, the plastic additive Bisphenol A (BPA) is classified as substance of very high concern (EU ECHA 2017). A correlation between...
Due to its endocrine disruptive activity, the plastic additive Bisphenol A (BPA) is classified as substance of very high concern (EU ECHA 2017). A correlation between environmental exposure to BPA and congenital defects has been described in humans and in experimental species including the amphibian Xenopus laevis, where severe branchial defects were associated to lethality. The exposure of X. laevis embryos to the BPA analogue bisphenol B (BPB) was recently linked to similar teratogenic effects, with BPB having relative potency about 3 times higher than BPA. The combined BPA-BPB exposure is realistic as both BPA and BPB are detected in human samples and environment. Limited experimental data are available on the combined developmental toxicity of BPA and BPB. The aim of the present work is to evaluate the effects of BPA and BPB mixture in the X. laevis development model, using R-FETAX procedure. The exposure was limited to the first day of development (corresponding to the phylotypic developmental period, common to all vertebrates). Samples were monitored for lethal effects during the full six-day test period and the external morphology was evaluated at the end of the test. Mixture effects were described by modelling, using the PROAST software package. Overall data modelling showed that dose-addiction could not be rejected, suggesting a health concern for co-exposure.
PubMed: 38866257
DOI: 10.1016/j.reprotox.2024.108614 -
Proceedings of the National Academy of... Jun 2024Legacy effects describe the persistent, long-term impacts on an ecosystem following the removal of an abiotic or biotic feature. Redlining, a policy that codified racial...
Legacy effects describe the persistent, long-term impacts on an ecosystem following the removal of an abiotic or biotic feature. Redlining, a policy that codified racial segregation and disinvestment in minoritized neighborhoods, has produced legacy effects with profound impacts on urban ecosystem structure and health. These legacies have detrimentally impacted public health outcomes, socioeconomic stability, and environmental health. However, the collateral impacts of redlining on wildlife communities are uncertain. Here, we investigated whether faunal biodiversity was associated with redlining. We used home-owner loan corporation (HOLC) maps [grades A (i.e., "best" and "greenlined"), B, C, and D (i.e., "hazardous" and "redlined")] across four cities in California and contributory science data (iNaturalist) to estimate alpha and beta diversity across six clades (mammals, birds, insects, arachnids, reptiles, and amphibians) as a function of HOLC grade. We found that in greenlined neighborhoods, unique species were detected with less sampling effort, with redlined neighborhoods needing over 8,000 observations to detect the same number of unique species. Historically redlined neighborhoods had lower native and nonnative species richness compared to greenlined neighborhoods across each city, with disparities remaining at the clade level. Further, community composition (i.e., beta diversity) consistently differed among HOLC grades for all cities, including large differences in species assemblage observed between green and redlined neighborhoods. Our work spotlights the lasting effects of social injustices on the community ecology of cities, emphasizing that urban conservation and management efforts must incorporate an antiracist, justice-informed lens to improve biodiversity in urban environments.
Topics: Biodiversity; Animals; California; Cities; Animals, Wild; Ecosystem; Humans; Conservation of Natural Resources
PubMed: 38861597
DOI: 10.1073/pnas.2321441121 -
The ISME Journal Jan 2024Phylosymbiosis is an association between host-associated microbiome composition and host phylogeny. This pattern can arise via the evolution of host traits, habitat...
Phylosymbiosis is an association between host-associated microbiome composition and host phylogeny. This pattern can arise via the evolution of host traits, habitat preferences, diets, and the co-diversification of hosts and microbes. Understanding the drivers of phylosymbiosis is vital for modelling disease-microbiome interactions and manipulating microbiomes in multi-host systems. This study quantifies phylosymbiosis in Appalachian salamander skin in the context of infection by the fungal pathogen Batrachochytrium dendrobatidis (Bd), while accounting for environmental microbiome exposure. We sampled ten salamander species representing >150M years of divergence, assessed their Bd infection status, and analysed their skin and environmental microbiomes. Our results reveal a significant signal of phylosymbiosis, whereas the local environmental pool of microbes, climate, geography, and Bd infection load had a smaller impact. Host-microbe co-speciation was not evident, indicating that the effect stems from the evolution of host traits influencing microbiome assembly. Bd infection is correlated with host phylogeny and the abundance of Bd-inhibitory bacterial strains, suggesting that the long-term evolutionary dynamics between salamander hosts and their skin microbiomes affect the present-day distribution of the pathogen, along with habitat-linked exposure risk. Five Bd-inhibitory bacterial strains showed unusual generalism: occurring in most host species and habitats. These generalist strains may enhance the likelihood of probiotic manipulations colonising and persisting on hosts. Our results underscore the substantial influence of host-microbiome eco-evolutionary dynamics on environmental health and disease outcomes.
Topics: Animals; Urodela; Microbiota; Skin; Symbiosis; Phylogeny; Batrachochytrium; Bacteria
PubMed: 38861457
DOI: 10.1093/ismejo/wrae104 -
Integrated Environmental Assessment and... Jun 2024Since 2019, the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) has actively developed pesticide environmental risk assessment (ERA)...
Since 2019, the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) has actively developed pesticide environmental risk assessment (ERA) frameworks adapted to Brazil's specific ecological contexts. This endeavor, supported by funding from the Brazilian Ministry of Justice and in partnership with academic institutions, has led to a concerted effort to establish ERA protocols for various taxa, including birds and mammals, soil organisms, aquatic organisms, and reptiles and amphibians. The outcomes of this initiative were conveyed in two workshops held in February and November 2023, during which the agency communicated its findings to the technical-regulatory community. This article represents one of three articles that provide more detailed insights into the ERA propositions for all taxa. In this article, we summarize the proposals for aquatic organisms presented and discussed during the workshops, which can be used as an informational source by the technical-regulatory community. Integr Environ Assess Manag 2024;00:1-6. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
PubMed: 38860613
DOI: 10.1002/ieam.4967