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1.
Dis Aquat Organ ; 144: 133-142, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33955851

RESUMO

Complex interactions among hosts, pathogens, and the environment affect the vulnerability of amphibians to the emergence of infectious diseases such as chytridiomycosis, caused by Batrachochytrium dendrobatidis (Bd). Boana curupi is a forest-dwelling amphibian endemic to the southern Atlantic Forest of South America, a severely fragmented region. Here, we evaluated whether abiotic factors (including air and water temperature, relative air humidity, and landscape) are correlated with chytrid infection intensity and prevalence in B. curupi. We found individuals infected with Bd in all populations sampled. Prevalence ranged from 25-86%, and the infection burden ranged from 1 to over 130000 zoospore genomic equivalents (g.e.) (mean ± SD: 4913 ± 18081 g.e.). The infection load differed among populations and was influenced by forest cover at scales of 100, 500, and 1000 m, with the highest infection rates recorded in areas with a higher proportion of forest cover. Our results suggest that the fungus is widely distributed in the populations of B. curupi in southern Brazil. Population and disease monitoring are necessary to better understand the relationships between host, pathogen, and environment, especially when, as in the case of B. curupi, threatened species are involved.


Assuntos
Quitridiomicetos , Micoses , Anfíbios , Animais , Anuros , Brasil/epidemiologia , Florestas , Micoses/epidemiologia , Micoses/veterinária
2.
Vet Clin North Am Exot Anim Pract ; 24(2): 397-418, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33892893

RESUMO

This article is aimed to help the reader to understand better how to diagnose and treat different respiratory diseases in Psittaciformes (parrot-like birds). The article starts from a review of avian respiratory anatomy and physiology, and then moves forward into diagnostic techniques, most common diseases, split in species and anatomic location, and common treatment regimens.


Assuntos
Infecções Bacterianas/veterinária , Doenças das Aves/diagnóstico , Micoses/veterinária , Papagaios/anatomia & histologia , Viroses/veterinária , Animais , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Infecções Bacterianas/patologia , Doenças das Aves/microbiologia , Doenças das Aves/patologia , Micoses/diagnóstico , Micoses/microbiologia , Micoses/patologia , Papagaios/fisiologia , Viroses/diagnóstico , Viroses/patologia , Viroses/virologia
3.
J Zoo Wildl Med ; 52(1): 300-305, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33827189

RESUMO

Batrachochytrium dendrobatidis (Bd) is an important fungal pathogen present in wild hellbender (Cryptobranchus alleganiensis) populations that appears to cause disease during novel exposure and acute stress. Hellbender repatriation efforts are ongoing to combat declining populations, but mortality by chytridiomycosis (disease from Bd) after release has been reported. The goal was to determine whether a safe antifungal agent could be administered and provide prolonged plasma concentrations without repeated handling. A subcutaneous implant impregnated with 24.5 mg of terbinafine was tested in three juvenile eastern hellbenders (C. a. alleganiensis) raised in human care, and plasma terbinafine concentrations were recorded from weekly to biweekly for 141 days. Plasma concentrations were variable, with peak plasma concentrations of 1,610, 112, and 66 ng/ml between 28 and 56 days postimplant. Although all hellbenders achieved plasma concentrations above the published minimum inhibitory concentration for terbinafine against Bd zoospores (63 ng/ml) at several time points, only one individual remained above this threshold for more than two consecutive time intervals. Results show the potential for these implants as a prophylaxis for chytridiomycosis in captive-to-wild hellbender releases. However, further investigation will be needed to determine the plasma concentrations required to achieve prophylaxis in vivo and implant reliability.


Assuntos
Antifúngicos/uso terapêutico , Micoses/veterinária , Terbinafina/uso terapêutico , Urodelos , Animais , Antifúngicos/administração & dosagem , Antifúngicos/sangue , Implantes de Medicamento , Micoses/prevenção & controle , Absorção Subcutânea , Terbinafina/administração & dosagem , Terbinafina/sangue
4.
J Zoo Wildl Med ; 52(1): 373-378, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33827201

RESUMO

Thirteen wild-caught hellbenders (Cryptobranchus alleganiensis) were treated for Batrachochytrium dendrobatidis with continuous chloramphenicol baths at concentrations of 20 mg/L for 14 days and 200 mg/L for 14 days. Clinical signs and deaths continued after treatment with 20 mg/L chloramphenicol but ceased after treatment with 200 mg/L chloramphenicol. No evidence of toxicity was found on hematologic tests, necropsy, or histopathologic examination. Lower infection burdens were detected after treatment with chloramphenicol, but infection rates were unchanged. Chloramphenicol may be useful as a treatment for B. dendrobatidis in hellbenders but did not clear hellbenders of infection.


Assuntos
Anfíbios/microbiologia , Antibacterianos/uso terapêutico , Cloranfenicol/uso terapêutico , Micoses/veterinária , Animais , Micoses/tratamento farmacológico
5.
J Zoo Wildl Med ; 52(1): 379-388, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33827202

RESUMO

This case series describes six confirmed cases of mycotic encephalitis and/or mycotic pneumonia in southern pudu (Pudu puda). One case involved a 10.5-yr-old intact female that presented with an inability to stand, eventually progressing to grand mal seizures. Magnetic resonance imaging showed a lesion within the cerebellar vermis with edema causing cerebellar herniation. The animal was euthanized based on a grave prognosis. Gross and histologic examination revealed primary central nervous system phaeohyphomycosis. Curvularia spicifera was sequenced from the cerebellar tissue. This is the first time this fungus has been reported as a primary central nervous system infection in an artiodactyl species. The remaining five cases occurred in neonates between 17 and 67 days old. Clinical signs varied widely, including facial swelling, weakness, posterior paresis, and sudden death. Antifungal therapy was initiated in three neonatal animals but was unsuccessful in each case. All neonates had active mycotic pneumonia caused by Aspergillus fumigatus or Mucor spp. at time of death; four of these animals also had disseminated disease that caused mycotic encephalitis. This case series indicates that fungal disease should be included in the differential diagnosis list of any pudu presenting for neurologic or respiratory clinical signs.


Assuntos
Cervos , Encefalite/veterinária , Fungos/isolamento & purificação , Micoses/veterinária , Pneumonia/microbiologia , Animais , Animais Recém-Nascidos , Animais de Zoológico , Encefalite/microbiologia , Feminino , Fungos/classificação , Masculino , Micoses/epidemiologia , Micoses/microbiologia
6.
Dis Aquat Organ ; 144: 99-106, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33830073

RESUMO

Environmental variation along elevational gradients shapes conditions for pathogen development, which influences disease outcomes. Chytridiomycosis is a non-vectored disease caused by the aquatic fungus Batrachochytrium dendrobatidis (Bd) and is responsible for massive declines of amphibian populations all over the world. Several biotic and abiotic factors are known to influence Bd infection dynamics in amphibians, including temperature and host species richness. Here, we quantified Bd prevalence and load along an elevational gradient in the Caparaó National Park (CNP), Brazil, and tested for associations of Bd infections with elevation, temperature, and species richness. We hypothesized that Bd infections would increase as local species richness decreased with elevation. We detected Bd along the entire elevational gradient and found a negative association between infection load and elevation. We did not detect significant associations between infection prevalence and elevation. Our findings are consistent with other wide elevational gradient studies, but are contrary to 2 other studies performed in the Atlantic Forest. We did not find the minimum elevational range that should be sampled to detect the influence of elevation on Bd variation. Our study represents the widest elevational gradient that has been sampled in Brazil and contributes to a better understanding of Bd distribution and dynamics in natural systems.


Assuntos
Quitridiomicetos , Micoses , Anfíbios , Animais , Brasil/epidemiologia , Florestas , Micoses/epidemiologia , Micoses/veterinária
7.
Dis Aquat Organ ; 143: 101-108, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33570043

RESUMO

Wildlife disease is a major cause of global biodiversity loss. Amongst the most devastating is the disease chytridiomycosis, caused by the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd). This disease has contributed to declines and extinctions in hundreds of amphibian species, but not all species are affected equally. Some amphibian hosts are capable of carrying high levels of Bd infection without population declines, acting as reservoir species for the pathogen and driving population declines in sympatric species. In Australia, several species have been proposed as reservoir species; however, our understanding of Bd is derived from studies that are highly geographically and taxonomically biased, and our ability to extrapolate from these systems is unknown. We examined the prevalence and intensity of Bd infection in 3 frog species in a previously unstudied host-pathogen system in temperate eastern Australia: the Blue Mountains tree frog Litoria citropa, a poorly-known species predicted to be susceptible to Bd infection; and the common eastern froglet Crinia signifera and the stony creek frog L. lesueuri, which have both been identified as reservoir species in other regions. We found that L. citropa and L. lesueuri were infected with Bd at a high prevalence and often high intensity, while the reverse was true for C. signifera. All species were detected at moderate abundance and there was no evidence of morbidity and mortality. Our findings do not support C. signifera and L. lesueuri being reservoir species in this system, highlighting the importance of region-specific studies to inform conservation management.


Assuntos
Quitridiomicetos , Micoses , Animais , Anuros , Austrália/epidemiologia , Micoses/epidemiologia , Micoses/veterinária
8.
J Zoo Wildl Med ; 51(4): 789-798, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33480559

RESUMO

Two- and three-toed sloths (Choloepus spp. and Bradypus spp.) have become popular animals in American culture and in American zoos, where they are frequently used as animal ambassadors. Despite the increased focus on sloth species, the prevalence of infectious diseases in sloth populations and the associated clinical consequences are relatively unknown. This study reviewed all published literature from 1809 to 2019 that examined infectious agents in both captive and wild populations of either two- or three-toed sloths. Online databases were electronically searched for relevant manuscripts using strings of inclusion and exclusion terms, resulting in an initial identification of 5,364 articles. After removing duplications and conducting two relevance screenings, 57 manuscripts were included in the full review. A total of 1,769 individual two-toed sloths and 879 individual three-toed sloths were accounted for in the included studies, with evidence of infection or exposure to infectious agents in 647 (36.6%) and 222 (25.3%) individual two- and three-toed sloths, respectively. Approximately 74% of documented infections were cryptic fungal, parasitic, and viral infections. The remaining 26% of infections represent those that were associated with clinical signs of disease. The infectious agents reported were bacterial (84), parasitic (20), viral (9), and fungal (4). Significant knowledge gaps remain regarding clinical and subclinical infectious disease prevalence and impact in both free-ranging and captive sloths.


Assuntos
Infecções Bacterianas/veterinária , Micoses/veterinária , Doenças Parasitárias em Animais/parasitologia , Bichos-Preguiça , Viroses/veterinária , Animais , Infecções Bacterianas/microbiologia , Micoses/microbiologia , Viroses/virologia
9.
Crit Rev Microbiol ; 47(3): 275-289, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33513315

RESUMO

The global scenario of antimicrobial resistance is alarming, and the development of new drugs has not appeared to make substantial progress. The constraints on drug discovery are due to difficulties in finding new targets for therapy, the high cost of development, and the mismatch between the time of drug introduction in a clinic and microorganism adaptation to a drug. Policies to address neglected diseases miss the broad spectrum of mycosis. Society is not aware of the actual threat represented by fungi to human health, food security, and biodiversity. The evidence discussed here is critical for warning governments to establish effective surveillance policies for fungi.HIGHLIGHTSFungal diseases are ignored even among neglected disease classifications.There are few options to treat mycoses, which is an increasing concern regarding fungal resistance to drugs, as evidenced by the spread of Candida auris.Fungal diseases represent a real threat to human health and food security.Investment in research to investigate the potential of repurposing drugs already in use could obtain results in the short term.


Assuntos
Antifúngicos/uso terapêutico , Fungos/efeitos dos fármacos , Micoses/veterinária , Animais , Farmacorresistência Fúngica , Fungos/genética , Fungos/fisiologia , Humanos , Micoses/microbiologia
10.
Dis Aquat Organ ; 142: 171-176, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33331284

RESUMO

Infection by the chytrid fungus Batrachochytrium dendrobatidis (Bd) is a major threat to amphibians and has caused catastrophic global declines of amphibian populations. Some studies have detected a seasonal pattern of infection associated with the local climate, and although most of them have focused on investigating the seasonality of Bd in relation to its impacts on amphibians, fewer have aimed to understand the chytrid persistence in the amphibian assemblage over seasons by investigating reservoir hosts. Since tadpoles are generally tolerant to Bd infection, they often play a relevant role in local disease dynamics. Thus, we hypothesized that tadpoles of Boana faber, a species that can be found in permanent ponds throughout the seasons, would function as Bd reservoirs. We therefore investigated Bd infection prevalence in tadpoles of this species over 2 yr in a nature reserve. As expected, we detected a seasonal variation of Bd infection, with a higher prevalence of Bd during the coldest months (winter) when compared to the warmer months (summer). Interestingly, our seasonal-trend decomposition analysis showed that Bd prevalence is increasing annually in the area, which could represent either a natural fluctuation of this pathogen, or an imminent threat to that anuran assemblage. With this study, we highlight the tadpole of B. faber as a potential reservoir for Bd, and we suggest that monitoring Bd in such hosts could be a powerful tool for identifying priority areas for amphibian conservation.


Assuntos
Quitridiomicetos , Micoses , Anfíbios , Animais , Larva , Micoses/epidemiologia , Micoses/veterinária , Lagoas , Prevalência , Estações do Ano
11.
Dis Aquat Organ ; 142: 177-187, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33331285

RESUMO

Amphibians have been facing a pandemic caused by the deadly fungus Batrachochytrium dendrobatidis (Bd). Although studies have elucidated cutaneous and homeostatic disturbances, it is still unknown if the hepatic function can be affected or if hepatic effects differ among host species. Thus, we evaluated the effects of an experimental Bd infection on the liver (histopathology and the hepatosomatic index) of 2 anuran species (Xenopus laevis and Physalaemus albonotatus) with different susceptibilities to Bd infection and compared them to uninfected controls. Bd infection increased the melanomacrophage cell area and induced leukocyte infiltration in both species. The effects were more pronounced in the sensitive species, P. albonotatus, which showed severe reduction in glycogen stores and liver atrophy, due to energetic imbalance. Hepatocytes of P. albonotatus also showed ballooning degeneration (vacuolization), which could lead to cell death and liver failure. Our results provide evidence that although the sensitive species showed more severe effects, the tolerant species also had hepatic responses to the infection. These findings indicate that hepatic function can play an important role in detoxification and in immune responses to chytridiomycosis, and that it may be used as a new biomarker of health status in chytrid infections.


Assuntos
Quitridiomicetos , Micoses , Anfíbios , Animais , Anuros , Suscetibilidade a Doenças/veterinária , Fígado , Micoses/veterinária
12.
Dis Aquat Organ ; 142: 225-237, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33331290

RESUMO

The chytrid fungus Batrachochytrium dendrobatidis (Bd) infects numerous amphibian species worldwide and is suggested to drive population declines and extinction events. We report a study of Bd infection at the northernmost distribution of the European yellow-bellied toad Bombina variegata. A total of 577 individuals from ponds in 16 study sites were sampled for DNA and Bd throughout the breeding season. Microsatellite genotyping revealed 3 genetic clusters for the host B. variegata with an overall low genetic diversity. One of the clusters displayed a low microsatellite heterozygosity, a high inbreeding coefficient as well as high Bd infection prevalence and intensities. Multi-model estimates identified site, time of sampling, and heterozygosity to be important predictors of an individual's Bd infection status, and identified a strong effect of site on individual Bd infection intensity. The study site effects are suggestive of localized infection peaks, and the increase of individual Bd infection probabilities towards the end of the sampling period suggests cumulative infection during the breeding season. This study highlights the need for regular monitoring of Bd infection variables at multiple localities and times to gain insights into Bd dynamics. Due to the detected relationship between individual Bd infection status and heterozygosity, conservation measures should focus on the maintenance of high genetic diversity and connectivity within and among amphibian populations.


Assuntos
Quitridiomicetos , Micoses , Animais , Anuros , Bufonidae , Quitridiomicetos/genética , Repetições de Microssatélites , Micoses/epidemiologia , Micoses/veterinária
13.
Nat Commun ; 11(1): 5393, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33106491

RESUMO

Wildlife diseases are contributing to the current Earth's sixth mass extinction; one disease, chytridiomycosis, has caused mass amphibian die-offs. While global spread of a hypervirulent lineage of the fungus Batrachochytrium dendrobatidis (BdGPL) causes unprecedented loss of vertebrate diversity by decimating amphibian populations, its impact on amphibian communities is highly variable across regions. Here, we combine field data with in vitro and in vivo trials that demonstrate the presence of a markedly diverse variety of low virulence isolates of BdGPL in northern European amphibian communities. Pre-exposure to some of these low virulence isolates protects against disease following subsequent exposure to highly virulent BdGPL in midwife toads (Alytes obstetricans) and alters infection dynamics of its sister species B. salamandrivorans in newts (Triturus marmoratus), but not in salamanders (Salamandra salamandra). The key role of pathogen virulence in the complex host-pathogen-environment interaction supports efforts to limit pathogen pollution in a globalized world.


Assuntos
Anuros/microbiologia , Quitridiomicetos/patogenicidade , Micoses/veterinária , Salamandridae/microbiologia , Urodelos/microbiologia , Animais , Quitridiomicetos/classificação , Quitridiomicetos/fisiologia , Micoses/microbiologia , Virulência
15.
Dis Aquat Organ ; 141: 1-14, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32940246

RESUMO

This study investigated the antifungal activity of 5 essential oils (EOs) towards yeasts recovered from diseased fishes; and focused on the efficacy of one EO (carvacrol) on growth performance, non-specific immunity, and disease resistance of Nile tilapia Oreochromis niloticus against Cryptococcus uniguttulatus challenge. Thymoquinone, thymol, carvacrol, eugenol, and cinnamon were first tested in vitro against 20 clinical yeast strains in comparison with antifungal drugs (fluconazole, ketoconazole, itraconazole, amphotericin B, nystatin, and clotrimazole) using disc diffusion and broth microdilution methods. For the in vivo challenge, fish (n = 150) were divided into 5 groups (carvacrol prophylaxis, carvacrol treatment, itraconazole treatment, unchallenged control, and positive control; 30 fish group-1) with 3 replicates. Phagocytic activity, reactive oxygen species production, reactive nitrogen species production, myeloperoxidase, lysozyme activity, and total immunoglobulins were tested before and after challenge. Relative percent survival (RPS) and mortality percent were determined as indicators for functional immunity. EOs displayed divergent degrees of antifungal activity, and carvacrol was the most effective against the tested yeasts. The dietary additive of carvacrol significantly enhanced growth performance, all immunological parameters, and the RPS values (90%) compared to other treatments. This unique experimental model indicates that carvacrol seems promising not only for enhancing immunity and promoting fish growth, but also for controlling emerging fungal infections. Future studies should investigate different concentrations of carvacrol as well as its antifungal activity in different fish species.


Assuntos
Ciclídeos , Criptococose/veterinária , Cryptococcus , Doenças dos Peixes , Micoses/veterinária , Animais , Cimenos , Dieta , Óleos Voláteis
16.
Dis Aquat Organ ; 140: 209-218, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32880378

RESUMO

The chytrid fungus Batrachochytrium dendrobatidis (Bd) has caused worldwide declines in amphibian populations. While Bd is widespread in southern and central Europe, its occurrence and distribution in northernmost Europe is mostly unknown. We surveyed for Bd in breeding anurans in Sweden by sampling 1917 amphibians from 101 localities and 3 regions in Sweden (southern, northern and central). We found that Bd was widespread in southern and central Sweden, occurring in all 9 investigated species and in 45.5% of the 101 localities with an overall prevalence of 13.8%. No infected individuals were found in the 4 northern sites sampled. The records from central Sweden represent the northernmost records of Bd in Europe. While the proportion of sites positive for Bd was similar between the southern and central regions, prevalence was much higher in the southern region. This was because southern species with a distribution mainly restricted to southernmost Sweden had a higher prevalence than widespread generalist species. The nationally red-listed green toad Bufotes variabilis and the fire-bellied toad Bombina bombina had the highest prevalence (61.4 and 48.9%, respectively). Across species, Bd prevalence was strongly positively, correlated with water temperature at the start of egg laying. However, no individuals showing visual signs of chytridiomycosis were found in the field. These results indicate that Bd is widespread and common in southern and central Sweden with southern species, breeding in higher temperatures and with longer breeding periods, having higher prevalence. However, the impact of Bd on amphibian populations in northernmost Europe remains unknown.


Assuntos
Quitridiomicetos , Micoses/veterinária , Anfíbios , Animais , Europa (Continente) , Prevalência , Suécia
17.
PLoS One ; 15(9): e0235370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915779

RESUMO

Controlled experiments are one approach to understanding the pathogenicity of etiologic agents to susceptible hosts. The recently discovered fungal pathogen, Batrachochytrium salamandrivorans (Bsal), has resulted in a surge of experimental investigations because of its potential to impact global salamander biodiversity. However, variation in experimental methodologies could thwart knowledge advancement by introducing confounding factors that make comparisons difficult among studies. Thus, our objective was to evaluate if variation in experimental methods changed inferences made on the pathogenicity of Bsal. We tested whether passage duration of Bsal culture, exposure method of the host to Bsal (water bath vs. skin inoculation), Bsal culturing method (liquid vs. plated), host husbandry conditions (aquatic vs. terrestrial), and skin swabbing frequency influenced diseased-induced mortality in a susceptible host species, the eastern newt (Notophthalmus viridescens). We found that disease-induced mortality was faster for eastern newts when exposed to a low passage isolate, when newts were housed in terrestrial environments, and if exposure to zoospores occurred via water bath. We did not detect differences in disease-induced mortality between culturing methods or swabbing frequencies. Our results illustrate the need to standardize methods among Bsal experiments. We provide suggestions for future Bsal experiments in the context of hypothesis testing and discuss the ecological implications of our results.


Assuntos
Quitridiomicetos/patogenicidade , Micoses/veterinária , Urodelos/microbiologia , Animais , Técnicas de Cultura de Células , Quitridiomicetos/isolamento & purificação , Quitridiomicetos/fisiologia , Micoses/microbiologia , Micoses/patologia , Pele/microbiologia , Pele/patologia , Coloração e Rotulagem , Urodelos/fisiologia
18.
PLoS One ; 15(9): e0239001, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915896

RESUMO

White-nose syndrome is a fungal disease responsible for the rapid decline of North American bat populations. This study addressed a novel method for inactivating Pseudogymnoascus destructans, the causative agent of WNS, using ultraviolet A (UVA) or B (UVB) radiation in combination with methoxsalen, a photosensitizer from the furanocoumarin family of compounds. Fungal spore suspensions were diluted in micromolar concentrations of methoxsalen (50-500 µM), then exposed to fixed doses of UVA radiation (500-5000 mJ/cm2), followed by plating on germination media. These plates were examined for two to four weeks for evidence of spore germination or inactivation, along with resultant growth or inhibition of P. destructans colonies. Pretreatment of fungal spores with low doses of methoxsalen resulted in a UVA dose-dependent inactivation of the P. destructans spores. All doses of methoxsalen paired with 500 mJ/cm2 of UVA led to an approximate two-log10 (~99%) reduction in spore viability, and when paired with 1000 mJ/cm2, a four-log10 or greater (>99.99%) reduction in spore viability was observed. Additionally, actively growing P. destructans colonies treated directly with methoxsalen and either UVA or UVB radiation demonstrated UV dose-dependent inhibition and termination of colony growth. This novel approach of using a photosensitizer in combination with UV radiation to control fungal growth may have broad, practical application in the future.


Assuntos
Ascomicetos/efeitos da radiação , Quirópteros/microbiologia , Metoxaleno/administração & dosagem , Micoses/veterinária , Fármacos Fotossensibilizantes/administração & dosagem , Terapia Ultravioleta , Animais , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , Micoses/radioterapia , Esporos Fúngicos/patogenicidade , Esporos Fúngicos/efeitos da radiação , Síndrome
19.
Mol Ecol ; 29(17): 3167-3169, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32745298

RESUMO

What happens when two emergent diseases infect the same host? In a From the Cover article in this issue of Molecular Ecology, McDonald et al. (2020) compare transcriptomic responses to co-infection by the two chytrid fungi in the skin, liver and spleen of Eastern newts (Notophthalmus viridescens). Novel molecular tools, such as high-throughput DNA sequencing for genome discovery and transcriptomics, have revolutionized our understanding of host-pathogen interactions and disease ecology (Güimil et al. 2005; Rosenblum et al. 2012). For example, epidemiologists are using genomic data to track the spread of the emergent SARS-CoV-2 in real time, both locally and globally. RNA sequencing (RNA-Seq) is routinely employed to study response to disease in humans, improving disease diagnostics, profiling and development of intervention strategies. Transcriptomic profiles may be particularly informative for emergent diseases, whose pathologies and effect on host phenotype are poorly known. Fungal pathogens increasingly threaten a variety of wild and domesticated organisms (Fisher et al. 2012), and two chytrid fungi attacking amphibians are causing one of the worst losses of vertebrate biodiversity ever recorded (Scheele et al. 2019).


Assuntos
Quitridiomicetos/imunologia , Micoses/veterinária , Salamandridae/imunologia , Animais , Coinfecção/imunologia , Perfilação da Expressão Gênica , Humanos , Fígado/microbiologia , Micoses/imunologia , Micoses/microbiologia , Salamandridae/genética , Salamandridae/microbiologia , Pele/microbiologia , Baço/microbiologia , Transcriptoma/genética
20.
PLoS One ; 15(8): e0238252, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857797

RESUMO

We report on aerobic "environmental" bacteria isolated from European honey bees (Apis mellifera). We determined the number of culturable aerobic bacteria in the gut of nurse bees sampled from locations around Australia. Bees from healthy colonies had 107-108 aerobic bacteria per g of bee gut, while bees from colonies with chalkbrood consistently had significantly fewer bacteria (104-105 bacteria per g). When colonies recovered from chalkbrood, bacterial numbers returned to normal levels, suggesting that counting aerobic bacteria in the gut could be used to predict an outbreak of the disease. Furthermore, Western Australian bees from the "Better Bees" program (bred to promote hygienic behaviour) had significantly higher numbers of aerobic gut bacteria compared to regular bees from healthy colonies. Bacteria with the ability to inhibit the chalkbrood pathogen were found in most bees from regular colonies (> 60%) but only in a few "Better Bees" (10%). Phylogenetic analysis of aerobic bacterial isolates that inhibited the chalkbrood pathogen revealed a close relationship (>97% sequence identity) to the genera Bacillus, Klebsiella, Pantoea, Hafnia, and Enterobacter (bacteria that have previously been isolated from honey bees), but we also isolated Maccrococcus and Frigoribacterium species (bacteria that were not previously identified in bees). Finally, we investigated the ability of bacteria to inhibit the chalkbrood fungus Ascosphaera apis. Mass spectroscopy analysis revealed that the bee gut isolates Frigoribacterium sp. and Bacillus senegalensis produce gluconic acid. We further found that this simple sugar is involved in chalkbrood fungal hyphal lysis and cytoplasmic leakage. Our findings suggest that "environmental" gut bacteria may help bees to control the chalkbrood pathogen.


Assuntos
Abelhas/microbiologia , Microbioma Gastrointestinal , Micoses/veterinária , Animais , Austrália , Bactérias/genética , Bactérias/metabolismo , Criação de Abelhas , Micoses/microbiologia , Filogenia
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