ABSTRACT
The species interactions that structure natural communities are increasingly disrupted by radical habitat change resulting from the widespread processes of urbanization and species translocations. Although many species are disadvantaged by these changes, others thrive in these new environments, achieving densities that exceed those in natural habitats. Often the same species that benefit from urbanization are successful invaders in introduced habitats, suggesting that similar processes promote these species in both environments. Both processes may especially benefit certain species by modifying their interactions with harmful parasites ('enemy release'). To detect such modifications, we first need to identify the mechanisms underlying host-parasite associations in natural populations, then test whether they are disrupted in cities and introduced habitats. We studied the interaction between the cane toad Rhinella marina, a globally invasive species native to South America, and its Amblyomma ticks. Our field study of 642 cane toads across 46 sites within their native range in French Guiana revealed that 56% of toads carried ticks, and that toads with ticks were in poor body condition relative to uninfected conspecifics. Across natural and disturbed habitats tick prevalence and abundance increased with toad density, but this association was disrupted in the urban environment, where tick abundance remained low even where toad densities were high, and prevalence decreased with density. Reductions in the abundance of ticks in urban habitats may be attributable to pesticides (which are sprayed for mosquito control but are also lethal to ticks), and our literature review shows that tick abundance is generally lower in cane toads from urban habitats across South America. In the invasive range, ticks were either absent (in 1,960 toads from Puerto Rico, Hawai'i, Japan and Australia) or less abundant (in Florida and the Caribbean; literature review). The positive relationship between host density and parasite abundance is thought to be a key mechanism through which parasites regulate host populations; anthropogenic processes that disrupt this relationship may allow populations in urban and introduced habitats to persist at densities that would otherwise lead to severe impacts from parasites.
Subject(s)
Parasites , Animals , Australia , Bufo marinus , Florida , French Guiana , Introduced Species , Japan , Puerto Rico , South America , UrbanizationABSTRACT
Between mid-May and early June of 1839, members of the United States Exploring Expedition collected diverse anurans in the environs of Valparaíso, Chile, later described by Girard in 1853. Of this set of species, Metaeus timidus, described there as a new genus and species, attracts attention because is a name that practically disappeared from the herpetological literature. Its identification, along with that of the other Chilean taxa collected by the USEE (Cystignathus nebulosus Girard, 1853, Pleurodema bibroni Tschudi, 1838, Pleurodema elegans Bell, 1843, Bufo lugubrosus Girard, 1853, Bufo thaul Lesson, 1826 and Metaeus timidus Girard, 1853) are the main objectives of this contribution.
Subject(s)
Amphibians , Animals , Anura , Chile , Expeditions , United StatesABSTRACT
The morphological and histological structure of the brains of Bufo gargarizans and Cynops orientalis were observed by anatomy and light microscopy. The results show that the brains of Bufo gargarizans and Cynops orientalis are divided into 5 parts which include the telencephalon, diencephalon, mesencephalon, cerebellum and medulla oblongata. The telencephalon consists of the olfactory bulb and the cerebral hemisphere. The olfactory bulb is developed that has two pairs of olfactory nerve. Bufo gargarizan has a symmetrical oval hemisphere optic lobes; Cynops orientalis only has a spherical optic lobe. The cerebellum is situated behind the optic lobe and closely connected with the myelencephalon. In this paper, the morphological and histological differences between the two species are discussed. The proportion of cerebral hemisphere is gradually increasing, which correlated with a progressive increase in the number of neuronal cell classes, and reflected in behavior complexity.
La estructura morfológica e histológica de los cerebros de Bufo gargarizans y Cynops orientalis se observó mediante anatomía y microscopía óptica. Los resultados muestran que los cerebros de Bufo gargarizans y Cynops orientalis se dividen en 5 partes, que incluyen el telencéfalo, diencéfalo, mesencéfalo, cerebelo y mielencéfalo. El telencéfalo consiste en bulbo olfatorio y hemisferio cerebral. El bulbo olfatorio tiene dos pares de nervios olfatorios. Los lóbulos ópticos de Bufo gargarizans son ovalados y simétricos en ambos hemisferios cerebrales; Cynops orientalis tiene solo un lóbulo óptico esférico. El cerebelo está situado detrás del lóbulo óptico y está estrechamente conectado con el mielencéfalo. En este trabajo, se discuten las diferencias morfológicas e histológicas entre las dos especies. El tamaño del hemisferio cerebral aumenta gradualmente, lo que se correlaciona con un aumento progresivo de células neuronales en los núcleos, reflejándose en la complejidad del comportamiento.
Subject(s)
Animals , Salamandridae/anatomy & histology , Brain/anatomy & histology , Bufo bufo/anatomy & histology , Anatomy, Comparative , Telencephalon/anatomy & histology , Mesencephalon/anatomy & histology , Cerebellum/anatomy & histology , Diencephalon/anatomy & histology , Myelencephalon/anatomy & histologyABSTRACT
Pathogens are increasingly implicated in amphibian declines but less is known about parasites and the role they play. We focused on a genus of nematodes (Rhabdias) that is widespread in amphibians and examined their genetic diversity, abundance (prevalence and intensity), and impact in a common toad (Rhinella horribilis) in Panama. Our molecular data show that toads were infected by at least four lineages of Rhabdias, most likely Rhabdias pseudosphaerocephala, and multiple lineages were present in the same geographic locality, the same host and even the same lung. Mean prevalence of infection per site was 63% and mean intensity of infection was 31 worms. There was a significant effect of host size on infection status in the wild: larger toads were more likely to be infected than were smaller conspecifics. Our experimental infections showed that toadlets that were penetrated by many infective Rhabdias larvae grew less than those who were penetrated by few larvae. Exposure to Rhabdias reduced toadlet locomotor performance (both sustained speed and endurance) but did not influence toadlet survival. The effects of Rhabdias infection on their host appear to be primarily sublethal, however, dose-dependent reduction in growth and an overall impaired locomotor performance still represents a significant reduction in host fitness.
Subject(s)
Bufo bufo/parasitology , Lung/parasitology , Rhabdiasoidea/genetics , Animals , Bufo bufo/growth & development , Female , Genetic Variation , Locomotion , Lung/pathology , Male , Panama , Parasite Egg Count , Prevalence , Rhabdiasoidea/pathogenicityABSTRACT
Apesar da alta frequência de intoxicações na clínica médica de pe-quenos animais, acidentes com anfíbios são considerados emergên-cias médicas devido ao elevado potencial tóxico de seu veneno, o qual tende a direcionar o curso clínico do paciente intoxicado para eventos fisiopatológicos, principalmente cardiovasculares e neuro-lógicos. Este estudo tem por finalidade descrever as principais alte-rações clínicas e laboratoriais observadas em um cão intoxicado por veneno de sapo identificado como sendo Rhinella icterica (Anura: Bufonidae), mediante identificação do anfíbio por imagens obtidas pelos tutores. A instituição precoce das estratégias terapêuticas ime-diatas (estabilização clínica) e tardias (terapia intensiva), assim como o estadiamento de lesões em outros órgãos e sistemas pelos exames complementares realizados de maneira simultânea, caracterizaram-se como essenciais para a melhora no prognóstico do animal.(AU)
Despite of the high frequency of intoxications in the small animal practice, amphibian accidents are considered medical emergencies due to the high toxic potential of their venom, which tends to direct the clinical course of the intoxicated patient for cardiovascular and neurological pathophysiological events. The present study aims to describe the clinical and laboratory alterations observed in a dog poisoned by frog venom identified as Rhinella icterica(Anura: Bufonidae), through the diagnostic confirmation made by the identification of the amphibian on the images obtained by the tutors. The early institution of immediate (clinical stabilization) and late (intensive therapy) therapeutic strategies, as well as the staging of injuries in other organs and systems by complementary tests performed simultaneously, were essential for the improvement in the prognosis this case.(AU)
Subject(s)
Animals , Dogs , Dogs/abnormalities , Amphibian Venoms/analysis , Amphibian Venoms/toxicity , Clinical Laboratory Techniques/veterinaryABSTRACT
Apesar da alta frequência de intoxicações na clínica médica de pe-quenos animais, acidentes com anfíbios são considerados emergên-cias médicas devido ao elevado potencial tóxico de seu veneno, o qual tende a direcionar o curso clínico do paciente intoxicado para eventos fisiopatológicos, principalmente cardiovasculares e neuro-lógicos. Este estudo tem por finalidade descrever as principais alte-rações clínicas e laboratoriais observadas em um cão intoxicado por veneno de sapo identificado como sendo Rhinella icterica (Anura: Bufonidae), mediante identificação do anfíbio por imagens obtidas pelos tutores. A instituição precoce das estratégias terapêuticas ime-diatas (estabilização clínica) e tardias (terapia intensiva), assim como o estadiamento de lesões em outros órgãos e sistemas pelos exames complementares realizados de maneira simultânea, caracterizaram-se como essenciais para a melhora no prognóstico do animal.
Despite of the high frequency of intoxications in the small animal practice, amphibian accidents are considered medical emergencies due to the high toxic potential of their venom, which tends to direct the clinical course of the intoxicated patient for cardiovascular and neurological pathophysiological events. The present study aims to describe the clinical and laboratory alterations observed in a dog poisoned by frog venom identified as Rhinella icterica(Anura: Bufonidae), through the diagnostic confirmation made by the identification of the amphibian on the images obtained by the tutors. The early institution of immediate (clinical stabilization) and late (intensive therapy) therapeutic strategies, as well as the staging of injuries in other organs and systems by complementary tests performed simultaneously, were essential for the improvement in the prognosis this case.
Subject(s)
Animals , Dogs , Dogs/abnormalities , Clinical Laboratory Techniques/veterinary , Amphibian Venoms/analysis , Amphibian Venoms/toxicityABSTRACT
5-MeO-DMT is a psychoactive substance found in high concentrations in the bufotoxin of the Colorado River Toad (Bufo alvarius). Emerging evidence suggests that vaporized 5-MeO-DMT may occasion mystical experiences of comparable intensity to those occasioned by more widely studied psychedelics such as psilocybin, but no empirical study has tested this hypothesis. Data was obtained from 20 individuals (M age = 38.9, ± 10.7; male = 55%, Caucasian = 85%) who were administered 5-MeO-DMT as part of a psychospiritual retreat program in Mexico. All participants received 50 mg of inhaled vaporized toad bufotoxin which contains 5-MeO-DMT and completed the Mystical Experience Questionnaire (MEQ30) approximately 4-6 h after their session. Administration of 5-MeO-DMT occasioned strong mystical experiences (MEQ30 Overall M intensity = 4.17, ± 0.64, range 0-5) and the majority (n = 15, 75%) had "a complete mystical experience" (≥60% on all MEQ30 subscales). Compared to a prior laboratory-based psilocybin study, there were no differences in the intensity of mystical effects between 5-MeO-DMT and a high dose (30 mg/70 kg) of psilocybin, but the intensity of mystical effects was significantly higher in the 5-MeO-DMT sample compared to moderate/high dose (20 mg/70 kg) of psilocybin (MEQ30 Total Score: p = 0.02, d = 0.81). Administration of vaporized 5-MeO-DMT reliably occasioned complete mystical experiences in 75% of individuals and was similar in intensity to high dose psilocybin administered in a laboratory setting. The short duration of action may be advantageous for clinical interventions and for studying mystical-type experiences.
ABSTRACT
El uso de biomarcadores hematológicos es importante para poder evaluar riesgos ambientales y la exposición a sustancias químicas potencialmente tóxicas y así poder desarrollar medidas que sirvan como señales de alarma temprana en ambientes contaminados. El objetivo de este trabajo fue determinar biomarcadores hematológicos en el sapo común Bufo (Rhinella) arenarum que proporcionen información para el diagnóstico de la salud de distintos ecosistemas de la provincia de Córdoba. Un total de 93 individuos adultos de Bufo (Rhinella) arenarum fueron capturados en cuatro sitios de la provincia de Córdoba y distintas variables ambientales del agua fueron medidas en cada sitio. Las muestras de sangre se obtuvieron mediante la punción de la vena angularis. Luego fueron teñidas con la tinción diferencial May Gr³nwald-Giemsa y fueron observadas mediante microscopio Zeiss Primo Star iLED para realizar el conteo de glóbulos blancos. Las variables ambientales del agua mostraron diferencias estadísticamente significativas entre las poblaciones, se registraron valores menores en “Alpa Corral”, mientras que “Villa Dálcar” presentó los mayores valores para dichas variables. No se encontraron diferencias estadísticamente significativas entre localidades en el recuento de glóbulos blancos (cada 1000 eritrocitos); sin embargo, en “Villa Dálcar” se registraron los ejemplares con mayor cantidad de leucocitos en el conteo de glóbulos blancos (425,48 ± 481,34). Mientras que para la fórmula leucocitaria, los linfocitos fueron las células más abundantes para los ejemplares de todos los sitios; encontrándose diferencias estadísticamente significativas entre cada localidad y “Alpa Corral”. Los ejemplares de “Villa Dálcar” presentaron diferencias estadísticamente significativas en relación a los monocitos y basófilos, registrándose altos valores para ambas células en los ejemplares de este sitio; mientras que en los ejemplares de “Cultivo” las diferencias se encontraron en eosinófilos y la relación neutrófilos/linfocitos. Estos resultados revelaron que de las cuatro localidades analizadas, “Villa Dálcar” representa la más afectada por las actividades antrópicas. Estas variaciones registradas en los parámetros hematológicos podrían considerarse evidencia de la posible presencia de agentes contaminantes en el lago “Villa Dálcar”.(AU)
Hematologic biomarkers are important to assess the environmental and health risks of exposure to potentially toxic chemicals, and for developing measures that serve as early warning signals in polluted areas. The aim of this study was to determine hematologic biomarkers of common toad Bufo (Rhinella) arenarum that provide information for the diagnosis of the health of ecosystems of Córdoba province. A total of 93 adult individuals of Bufo (Rhinella) arenarum were collected from four sites of Córdoba Province and hydric environmental variables were measured on each site. Blood samples were obtained by angularis vein puncture, smears of fresh blood were stained with May Gr³nwald-Giemsa and observed by using a microscope Carl Zeiss Primo Star (Pack 5), for white blood cell count. Water environmental variables showed statistically significant differences among localities, with the lowest values in “Alpa Corral” and highest values in “Villa Dálcar”. There were no statistically significant differences among individuals of different sites for white blood cells count. However, individuals from "Villa Dálcar" showed the highest number of white cells (425.48 ± 481.34). In the leukocyte formula, lymphocytes were most abundant white blood cells in individuals from all study sites. The blood parameters of toads from all sites showed statistically significant differences with individuals from “Alpa Corral”. "Villa Dálcar" Individuals exhibited significant differences in relation to monocytes and basophils with the highest values for both cell types. “Cultivo” locality showed significant differences for eosinophils and for the relationship neutrophils/ lymphocytes. These results revealed that “Villa Dálcar” represent the site most affected by human activities. In particular, changes recorded in hematological parameters could be giving evidence of the possible presence of contaminants in Lake “Villa Dálcar”.(AU)
ABSTRACT
El uso de biomarcadores hematológicos es importante para poder evaluar riesgos ambientales y la exposición a sustancias químicas potencialmente tóxicas y así poder desarrollar medidas que sirvan como señales de alarma temprana en ambientes contaminados. El objetivo de este trabajo fue determinar biomarcadores hematológicos en el sapo común Bufo (Rhinella) arenarum que proporcionen información para el diagnóstico de la salud de distintos ecosistemas de la provincia de Córdoba. Un total de 93 individuos adultos de Bufo (Rhinella) arenarum fueron capturados en cuatro sitios de la provincia de Córdoba y distintas variables ambientales del agua fueron medidas en cada sitio. Las muestras de sangre se obtuvieron mediante la punción de la vena angularis. Luego fueron teñidas con la tinción diferencial May Grünwald-Giemsa y fueron observadas mediante microscopio Zeiss Primo Star iLED para realizar el conteo de glóbulos blancos. Las variables ambientales del agua mostraron diferencias estadísticamente significativas entre las poblaciones, se registraron valores menores en “Alpa Corral”, mientras que “Villa Dálcar” presentó los mayores valores para dichas variables. No se encontraron diferencias estadísticamente significativas entre localidades en el recuento de glóbulos blancos (cada 1000 eritrocitos); sin embargo, en “Villa Dálcar” se registraron los ejemplares con mayor cantidad de leucocitos en el conteo de glóbulos blancos (425,48 ± 481,34). Mientras que para la fórmula leucocitaria, los linfocitos fueron las células más abundantes para los ejemplares de todos los sitios; encontrándose diferencias estadísticamente significativas entre cada localidad y “Alpa Corral”. Los ejemplares de “Villa Dálcar” presentaron diferencias estadísticamente significativas en relación a los monocitos y basófilos, registrándose altos valores para ambas células en los ejemplares de este sitio; mientras que en los ejemplares de “Cultivo” las diferencias se encontraron en eosinófilos y la relación neutrófilos/linfocitos. Estos resultados revelaron que de las cuatro localidades analizadas, “Villa Dálcar” representa la más afectada por las actividades antrópicas. Estas variaciones registradas en los parámetros hematológicos podrían considerarse evidencia de la posible presencia de agentes contaminantes en el lago “Villa Dálcar”.
Hematologic biomarkers are important to assess the environmental and health risks of exposure to potentially toxic chemicals, and for developing measures that serve as early warning signals in polluted areas. The aim of this study was to determine hematologic biomarkers of common toad Bufo (Rhinella) arenarum that provide information for the diagnosis of the health of ecosystems of Córdoba province. A total of 93 adult individuals of Bufo (Rhinella) arenarum were collected from four sites of Córdoba Province and hydric environmental variables were measured on each site. Blood samples were obtained by angularis vein puncture, smears of fresh blood were stained with May Grünwald-Giemsa and observed by using a microscope Carl Zeiss Primo Star (Pack 5), for white blood cell count. Water environmental variables showed statistically significant differences among localities, with the lowest values in “Alpa Corral” and highest values in “Villa Dálcar”. There were no statistically significant differences among individuals of different sites for white blood cells count. However, individuals from "Villa Dálcar" showed the highest number of white cells (425.48 ± 481.34). In the leukocyte formula, lymphocytes were most abundant white blood cells in individuals from all study sites. The blood parameters of toads from all sites showed statistically significant differences with individuals from “Alpa Corral”. "Villa Dálcar" Individuals exhibited significant differences in relation to monocytes and basophils with the highest values for both cell types. “Cultivo” locality showed significant differences for eosinophils and for the relationship neutrophils/ lymphocytes. These results revealed that “Villa Dálcar” represent the site most affected by human activities. In particular, changes recorded in hematological parameters could be giving evidence of the possible presence of contaminants in Lake “Villa Dálcar”.
Subject(s)
Animals , Bufo arenarum/blood , Leukocyte Count/methods , Argentina , Biomarkers/blood , Environmental Monitoring/methodsABSTRACT
The objective of this study was to explore the relationship between the retinal structure and its life adaptation to the environment of Ctenopharyngodon idella, Cynops orientalis, Bufo bufo gargarizans, Gekko japonicus and Columba livia . Measuring retinal thickness of each layer, the nuclei layer, and the diameter of each nuclear layer of the five animals, the statistical data analysis shows that: the nuclei layers of five animals are all 4, and their structures can be divided to 10 layers when observing with optical microscope. The retinal thickness of Ctenopharyngodon idella was 190.49 mm, Cynops orientalis was 173.07 µm, and the Bufo bufo gargarizans was 195.06 µm, Gekko japonicus was 224.32 µm and Columba livia was 174.10 µm. The number of retinal inner nuclear layers of Bufo bufo gargarizans and Gekko japonicus and Columba livia are more than their outer nuclear layers, on the contrary, retinal inner nuclear layers of Ctenopharyngodon idella and Cynops orientalis are less than their outer nuclear layers. The rod and cone layer of retina of Cynops orientalis were more advanced, but their nerve fiber layer (NFL) degraded highly, revealing a strong photosensitivity but a low visual sensitivity; to Columba livia , their NFL of retina are highly developed, so as their vision. The different structures and functions of the retina of Ctenopharyngodon idella, Cynops orientalis, Bufo bufo gargarizans, Gekko japonicus and Columba livia correspond with their behavioral characteristics and the living environment's change from aquatic to amphibious to land.
El objetivo de este estudio fue explorar la relación entre las estructuras de la retina y su adaptación al medioambiente en Ctenopharyngodon idella, Cynops orientalis, Bufo bufo gargarizans,Gekko japonicus y Columba livia . La medición del espesor de cada capa de la retina, la capa nuclear y su diámetro en los cinco animales, mostró a través del análisis estadístico que las capas nucleares en todos ellos fueron 4, y sus estructuras se pueden dividir en 10 capas cuando se observan con el microscopio óptico. El espesor de la retina de Ctenopharyngodon idella fue 190,49 µm, de Cynops orientalis fue 173,07 µm, de Bufo bufo gargarizans fue 195,06 µm, de Gekko japonicus fue 224,32 µm y de Columba livia fue 174,10 µm. El número de capas nucleares internas de la retina de Bufo gargarizans, Gekko japonicus y Columba livia fue mayor que sus capas nucleares externas, mientras que las capas nucleares internas de Ctenopharyngodon idella y Cynops orientalis fueron menos que las capas nucleares externas. La capa de conos y bastones de la retina de Cynops orientalis fue más desarrollada, pero su capa de fibras nerviosas presentó una elevada degeneración, lo que muestra una gran fotosensibilidad, pero una sensibilidad visual baja. En Columba livia, la capa de fibras nerviosas de la retina estuvo muy desarrollada, y de esta manera, su visión. El grado de desarrollo de las diferentes estructuras y funciones de la retina de Ctenopharyngodon idella, Cynops orientalis, Bufo bufo gargarizans, Gekko japonicus y Columba livia está relacionada con sus características de comportamiento y el cambio de las condiciones de las vidas acuática y anfibia en la tierra.
Subject(s)
Animals , Columbidae/anatomy & histology , Retina/anatomy & histology , Salamandridae/anatomy & histology , Bufo bufo/anatomy & histology , Carps/anatomy & histology , Lizards/anatomy & histology , Adaptation to Disasters , Histology, ComparativeABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Toads known as "cururú" (Rhinella schneideri) have been used in the Brazilian Pantanal and Paraguayan Chaco wetlands to treat erysipelas and cancer. The aim of the study was to assess the antiproliferative effect of the venom obtained from Rhinella schneideri and to identify its constituents by spectroscopic and spectrometric methods. MATERIALS AND METHODS: The venom was obtained by gentle pressing the parotid glands of the toads. The dry crude drug was analyzed by HPLC-MS-MS and chromatographed on Sephadex LH-20 to obtain purified compounds and fractions for spectroscopic analysis. The venom and fractions were evaluated for antiproliferative activity towards normal human lung fibroblasts (MRC-5) and four human cancer cell lines: gastric epithelial adenocarcinoma (AGS), lung cancer (SK-MES-1), bladder carcinoma (J82) and promyelocytic leukemia (HL-60). RESULTS: From the Rhinella schneideri venom, 29 compounds were isolated and/or identified by spectroscopic and spectrometric means. Three known alkaloids and five argininyl diacids were identified in the complex mixture by HPLC-MS-MS. Nine out of fifteen argininyl diacid derivatives of the bufadienolides bufalin, marinobufagin and telocinobufagin are reported for the first time and four argininyl diacids are described for the first time as natural products. The venom and the fractions 9-13 showed a remarkable antiproliferative effect, with IC50 values in the range 0.019-0.022, 0.035-0.040, 0.028-0.064, 0.042-0.056 and 0.044-0.052 µg/mL for MRC-5, AGS, SK-MES-1, J82 and HL-60 cell lines, respectively. Under the same experimental conditions, IC50 values of the reference compound etoposide were 2.296, 0.277, 1.295, 1.884 and 1.059 µg/mL towards MRC-5, AGS, SK-MES-1, J82 and HL-60 cells, respectively. CONCLUSIONS: The venom showed a strong antiproliferative effect towards human cancer cells and presented a high chemical diversity in its constituents, supporting its use as anticancer agent. These findings encourage further work on the chemistry and bioactivity of South American toad venoms.
Subject(s)
Amphibian Venoms/chemistry , Bufanolides/pharmacology , Cell Proliferation/drug effects , Fibroblasts/drug effects , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Brazil , Bufanolides/administration & dosage , Bufanolides/isolation & purification , Bufonidae , Cell Line , Cell Line, Tumor , Chromatography, High Pressure Liquid , Drug Screening Assays, Antitumor , Esters , Fibroblasts/metabolism , HL-60 Cells , Humans , Inhibitory Concentration 50 , Neoplasms/drug therapy , Neoplasms/pathology , Paraguay , Tandem Mass SpectrometryABSTRACT
Los anfibios son constituyentes integrales de ecosistemas naturales y agrícolas, y debido a su sensibilidad pueden ser utilizados como bioindicadores. La frecuencia de micronúcleos se emplea como un biomarcador que evalúa la respuesta a agentes genotóxicos. El objetivo del trabajo fue determinar y comparar la frecuencia de micronúcleos en eritrocitos de Bufo arenarum que habitan ambientes antrópicos de la ciudad de Río Cuarto. Se escogieron tres sitios modificados: un lago urbano Lago Villa Dálcar (33º06´S-64º22´W) y dos sitios de cultivo denominados Cultivo1 (33º05'S-64º26'W) y Cultivo 2 (33º05'S-64º25'W). Como control se escogió un área ubicada en las sierras de Comechingones, en el Campo Experimental Las Guindas (32º35'S- 64º42'W), pertenecientes a la UNRC. En cada sitio se recolectaron ocho individuos utilizando trampas de caída y relevamientos por encuentros visuales. A cada individuo se le extrajo sangre de la vena angularis inmediatamente después de la captura. Se realizaron dos extendidos por cada individuo, se dejaron secar al aire por 24 hs, luego se fijaron con metanol por 20 minutos y se colorearon con Giemsa al 5% durante 10 minutos. Posteriormente los frotis fueron analizados con microscopio (1000X) y se tomaron fotografías con cámara digital. La frecuencia de micronúcleos fue contabilizada para 4000 células por individuo. Se realizaron comparaciones utilizando el test de Kruskal-Wallis. Las frecuencias de micronúcleos encontradas son: Las Guindas: 0,17 ± 0,23; Cultivo1: 0,78 ± 0,28; Cultivo 2: 0,61 ± 0,45 y Villa Dálcar: 0,76 ± 0,47. Existen diferencias significativas entre el control y los demás sitios (p< 0,01). Los resultados obtenidos demuestran la relevancia en la aplicación del test de micronúcleos in vivo en anfibios anuros para comparar distintos ambientes. Estos resultados indicarían la necesidad de nuevas investigaciones y de un monitoreo más prolongado en el tiempo para estos ambientes, incluyendo por ejemplo otros tipos de biomarcadores, así como otras posibles especies representativas de la región.
Amphibians are integral constituents of natural and agricultural ecosystems, and because of their sensitivity can be used as bioindicators. Micronuclei test is used as a biomarker for determining the response to genotoxic agents. The purpose of this study was to determine and compare the frequency of micronuclei in peripheral blood erythrocytes of Bufo arenarum toads that inhabiting anthropic environments for the city of Rio Cuarto. Organisms used in the MN test were collected from three sites modified: an urban lakeVilla Dalcar (33º06´S-64º22´W) and two cultivation sites called Crop 1 (33º05'S-64º26'W) and Crop 2 (33º05'S-64º25'W). As a control site, an area in the mountains of Comechingones, Las Guindas (32º35'S-64º42'W), belonging to the UNRC was sampled. At each site, eight individuals were collected using pitfall traps and by visual encounter surveys. To each individual is bled from the vein angularis immediately after capture. We performed two extended for each individual, air-dried for 24 hours, then fixed with methanol for 20 minutes and stained with 5% Giemsa for 10 minutes. Then the smears were analyzed with microscope (1000X) and took pictures with digital camera. For each individual the frequency of micronuclei for 4000 cells was recorded. Comparisons were made using the Kruskal-Wallis test. Micronuclei frequencies found are: Las Guindas: 0.17± 0.23; Crop 1: 0.78 ± 0.28, Crop 2: 0.61 ± 0.45 and Villa Dalcar: 0.76 ± 0.47. There are significant differences between the control and the other sites (p< 0.01). These findings show the relevance in the application of micronucleus test in vivo for anuran amphibians to compare different environments. These results suggest the need for further research and monitoring longer time for these environments, including such other biomarkers, as well as other possible species representative of the region.
Subject(s)
Animals , Bufo arenarum/blood , Micronucleus Tests/methods , Agrochemicals/toxicity , Mutagenicity Tests , Argentina , Biomarkers/analysis , Environmental Monitoring/methodsABSTRACT
Los anfibios son constituyentes integrales de ecosistemas naturales y agrícolas, y debido a su sensibilidad pueden ser utilizados como bioindicadores. La frecuencia de micronúcleos se emplea como un biomarcador que evalúa la respuesta a agentes genotóxicos. El objetivo del trabajo fue determinar y comparar la frecuencia de micronúcleos en eritrocitos de Bufo arenarum que habitan ambientes antrópicos de la ciudad de Río Cuarto. Se escogieron tres sitios modificados: un lago urbano Lago Villa Dálcar (33º06´S-64º22´W) y dos sitios de cultivo denominados Cultivo1 (33º05S-64º26W) y Cultivo 2 (33º05S-64º25W). Como control se escogió un área ubicada en las sierras de Comechingones, en el Campo Experimental Las Guindas (32º35S- 64º42W), pertenecientes a la UNRC. En cada sitio se recolectaron ocho individuos utilizando trampas de caída y relevamientos por encuentros visuales. A cada individuo se le extrajo sangre de la vena angularis inmediatamente después de la captura. Se realizaron dos extendidos por cada individuo, se dejaron secar al aire por 24 hs, luego se fijaron con metanol por 20 minutos y se colorearon con Giemsa al 5% durante 10 minutos. Posteriormente los frotis fueron analizados con microscopio (1000X) y se tomaron fotografías con cámara digital. La frecuencia de micronúcleos fue contabilizada para 4000 células por individuo. Se realizaron comparaciones utilizando el test de Kruskal-Wallis. Las frecuencias de micronúcleos encontradas son: Las Guindas: 0,17 ± 0,23; Cultivo1: 0,78 ± 0,28; Cultivo 2: 0,61 ± 0,45 y Villa Dálcar: 0,76 ± 0,47. Existen diferencias significativas entre el control y los demás sitios (p< 0,01). Los resultados obtenidos demuestran la relevancia en la aplicación del test de micronúcleos in vivo en anfibios anuros para comparar distintos ambientes. Estos resultados indicarían la necesidad de nuevas investigaciones y de un monitoreo más prolongado en el tiempo para estos ambientes, incluyendo por ejemplo otros tipos de biomarcadores, así como otras posibles especies representativas de la región.(AU)
Amphibians are integral constituents of natural and agricultural ecosystems, and because of their sensitivity can be used as bioindicators. Micronuclei test is used as a biomarker for determining the response to genotoxic agents. The purpose of this study was to determine and compare the frequency of micronuclei in peripheral blood erythrocytes of Bufo arenarum toads that inhabiting anthropic environments for the city of Rio Cuarto. Organisms used in the MN test were collected from three sites modified: an urban lakeVilla Dalcar (33º06´S-64º22´W) and two cultivation sites called Crop 1 (33º05S-64º26W) and Crop 2 (33º05S-64º25W). As a control site, an area in the mountains of Comechingones, Las Guindas (32º35S-64º42W), belonging to the UNRC was sampled. At each site, eight individuals were collected using pitfall traps and by visual encounter surveys. To each individual is bled from the vein angularis immediately after capture. We performed two extended for each individual, air-dried for 24 hours, then fixed with methanol for 20 minutes and stained with 5% Giemsa for 10 minutes. Then the smears were analyzed with microscope (1000X) and took pictures with digital camera. For each individual the frequency of micronuclei for 4000 cells was recorded. Comparisons were made using the Kruskal-Wallis test. Micronuclei frequencies found are: Las Guindas: 0.17± 0.23; Crop 1: 0.78 ± 0.28, Crop 2: 0.61 ± 0.45 and Villa Dalcar: 0.76 ± 0.47. There are significant differences between the control and the other sites (p< 0.01). These findings show the relevance in the application of micronucleus test in vivo for anuran amphibians to compare different environments. These results suggest the need for further research and monitoring longer time for these environments, including such other biomarkers, as well as other possible species representative of the region.(AU)
ABSTRACT
The present paper deals with a histological study of the blood cells of Bufo Bufo gargarizans in different months: January, March, May, July and October. The methods used are by routine blood smear in Wright stain and observation in vivo. We found that in smears and in vivo two main types of cells of the red cells: mitotic as well as amitotic. While amitotic occurs all the year round, particularly in July, mitosis so far had been seen only in July. It is also found that there are plenty of neutrophils in the blood cells of Bufo Bufo gargarizans, furthermore, the nuclei of these cells are polymorphic, especially in January and March. Meanwhile, the concentration of red cells was lowest in May and highest in January; The concentration of white blood cells was highest in October and lowest in March; As to granulocytes, eosinophils in July and October had higher proportion, while neutrophils and basophils in July; in agranulocytes, mononuclear cells reached the highest value in March, lowest in January, lymphocytes and the maximum value appeared in May, the lowest value appeared in July. Morphological changes of thrombocytes were not obvious.
Se realizó el presente estudio histológico de las células sanguíneas de Bufo Bufo gargarizans en diferentes meses del año: enero, marzo, mayo, julio y octubre. Fueron utilizados métodos de rutina por frotis de sangre con tinción de Wright y observación in vivo. Encontramos dos tipos principales de células de glóbulos rojos al frotis como también en células in vivo: mitóticas y amitóticas. Por cuanto amitosis se produce durante todo el año, sobre todo en el mes de julio, la mitosis hasta el momento se había observado solamente en julio. Además, se encontró una gran cantidad de neutrófilos en los glóbulos de Bufo Bufo gargarizans. Los núcleos de estas células son polimórficos, especialmente en enero y marzo. La concentración de glóbulos rojos era más bajo en mayo y más alta en enero; la concentración de las células blancas de la sangre fue mayor en octubre y menor en marzo. En cuanto a los granulocitos, eosinófilos estos presentaron una mayor proporción en julio y octubre, mientras que los neutrófilos y basófilos registraran una mayor proporción en el mes de julio. Los agranulocitos y las células mononucleares alcanzaron el valor más alto en marzo, y el valor más bajo en enero. Los linfocitos y el valor máximo fue registrado en mayo, el valor más bajo fue registrado en julio. No fueron evidentes los cambios morfológicos de trombocitos, lo que podría tener relación con su estabilidad.
Subject(s)
Animals , Bufo bufo/anatomy & histology , Blood Cells/ultrastructure , Time FactorsABSTRACT
Morphometry structure of Sicilian green toad from the Nature Reserve "Monte Pellegrino" (north-western Sicily) was studied. A total of 666 individuals (354 males and 312 females) were captured in 2003 during reproduction period. Meaningful differences have statistically emerged among the two sexes and the body weight is the best parameter (up to 92 percent correct classification), followed by the length of the body (up to 90 percent correct classification). The simultaneous use of all the examined characters only increases of 1percent the probability for correct discrimination of the sex. In comparison to the dimension of other green toad populations studied by other authors, the body size of this sicilian population results elevated, similar to that of Corsica and of Sardinia. It is possible that the high dimension of the Sicilian population is the result of low competition with other amphibians species and/or to the absence of a winter latency.
Se realizó un estudio morfométrico de la estructura del sapo verde siciliano de la Reserva Natural "Monte Pellegrino" (norte-oeste de Sicilia). Un total de 666 individuos (354 machos y 312 hembras) fueron capturados desde el año 2003 durante la época de reproducción. Se encontraron diferencias estadísticamente significativas entre los dos sexos, donde el peso corporal fue el mejor parámetro (hasta 92 por ciento de clasificación correcta), seguido por la longitud corporal (hasta 90 por ciento de clasificación correcta). El uso simultáneo de todos los caracteres examinados solo aumentó un 1 por ciento la probabilidad de una correcta discriminación del sexo. En comparación con la dimensión de otras poblaciones de sapos verdes estudiados por otros autores, el tamaño del cuerpo de esta población siciliana resulta elevado, similar a las poblaciones de Córcega y Cerdeña. Es posible que la gran dimensión de la población siciliana pueda deberse al bajo nivel de competencia con anfibios otras especies y/o a la ausencia de una latencia de invierno.
Subject(s)
Humans , Male , Female , Biometry , Bufonidae/anatomy & histology , ItalyABSTRACT
Cloacal swabs and caecal contents sampled from 58 cane toads (Bufo marinus) in St George's parish, Grenada, during a 7-month period in 2011 were examined by an enrichment and selective culture method for presence of Salmonella spp. Twenty-four (41%) toads were positive for Salmonella spp. of which eight were Salmonella enterica serovar Javiana, and eight were S. enterica serovar Rubislaw. The other serovars were as follows: Montevideo, 6; Arechavaleta, 1; and serovar: IV:43:-:-, 1. The high frequency of isolation of serovar Javiana, an emerging human pathogen associated with several outbreaks in the recent years in the eastern United States, suggests a possible role for cane toads in transmission of this serovar. Although S. Rubislaw has been isolated from lizards, bats and cases of some human infections, there is no report of its carriage by cane toads, and in such high frequency. The rate of carriage of S. Montevideo, a cause for human foodborne outbreaks around the world was also over 10% in the 58 toads sampled in this study. The antimicrobial drug susceptibility tests against amoxicillin-clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, imipenem, nalidixic acid, streptomycin, tetracycline and trimethoprim-sulfamethoxazole showed that drug resistance is minimal and is of little concern. Antimicrobial resistance was limited to ampicillin and amoxicillin-clavulanic acid in one isolate of S. Javiana and one isolate of S. Rubislaw. This is the first report of isolation and antimicrobial susceptibilities of various Salmonella serovars not identified previously in cane toads in Grenada, West Indies.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bufo marinus/microbiology , Drug Resistance, Multiple, Bacterial , Salmonella Infections, Animal/microbiology , Salmonella/drug effects , Salmonella/isolation & purification , Animals , Feces/microbiology , Salmonella Infections, Animal/epidemiology , West Indies/epidemiologyABSTRACT
The water balance and the upper limit of osmotic tolerance of premetamorphic Rhinella arenarum larvae (Gosner's stage 26) was evaluated after semistatic incubation in electrolyte (NaCl) and non-electrolyte (mannitol) media following a protocol of progressively increased osmotic pressure. Wet and dry weights were measured to calculate the water content as a derived variable indicative of the hydric balance. Statistical analysis was performed using univariate and integrated multivariate analysis. Tadpoles survived in electrolyte and non-electrolyte solutions up to 200 mOsm. The discriminant function was the best tool to describe the responses of the animals to external environmental stress under experimental conditions. The results were compared with those obtained in previous studies using a protocol of acute exposure to the same media used in this study. It was concluded that a) multivariate analysis is an appropriate approach to describe the responses of tadpoles to changes in the environmental physicochemical parameters, and b) progressive and acute acclimation to the experimental solutions induced similar responses.(AU)
Avaliou-se o balanço hídrico e o limite superior de tolerância osmótica em larvas pré-metamórficas do Rhinella arenarum (etapa 26 de Gosner) sob condições de incubação semiestáticas, num meio eletrolítico (NaCl) e não eletrolítico (manitol), seguindo um protocolo de aumento progressivo da pressão osmótica do meio. A quantificação das respostas se efetuou por meio da medição dos valores de peso úmido e seco e do cálculo, a partir destes, do conteúdo de água, como variável derivada indicativa do equilíbrio hídrico. A análise estatística foi realizada usando análise univariada e multivariada. As larvas conseguiram sobreviver em soluções eletrolíticas e não eletrolíticas até 200 mOsm. A função discriminante foi a melhor ferramenta para descrever as respostas dos animais ao estresse osmótico ambiental. Os resultados foram comparados com os obtidos em estudos anteriores, usando um protocolo de exposição aguda aos mesmos meios de incubação usados neste estudo. Concluiu-se: a) a análise multivariada é a aproximação adequada para descrever as respostas das larvas às mudanças nos parâmetros físico-químicos do seu meio; e b) tanto a aclimatação progressiva, como as exposições agudas às soluções experimentais induziram as respostas semelhantes.(AU)
Subject(s)
Animals , Bufonidae/physiology , Bufonidae/metabolism , Larva/metabolism , Larva/physiology , Osmolar Concentration , Time FactorsABSTRACT
The water balance and the upper limit of osmotic tolerance of premetamorphic Rhinella arenarum larvae (Gosner's stage 26) was evaluated after semistatic incubation in electrolyte (NaCl) and non-electrolyte (mannitol) media following a protocol of progressively increased osmotic pressure. Wet and dry weights were measured to calculate the water content as a derived variable indicative of the hydric balance. Statistical analysis was performed using univariate and integrated multivariate analysis. Tadpoles survived in electrolyte and non-electrolyte solutions up to 200 mOsm. The discriminant function was the best tool to describe the responses of the animals to external environmental stress under experimental conditions. The results were compared with those obtained in previous studies using a protocol of acute exposure to the same media used in this study. It was concluded that a) multivariate analysis is an appropriate approach to describe the responses of tadpoles to changes in the environmental physicochemical parameters, and b) progressive and acute acclimation to the experimental solutions induced similar responses.
Avaliou-se o balanço hídrico e o limite superior de tolerância osmótica em larvas pré-metamórficas do Rhinella arenarum (etapa 26 de Gosner) sob condições de incubação semiestáticas, num meio eletrolítico (NaCl) e não eletrolítico (manitol), seguindo um protocolo de aumento progressivo da pressão osmótica do meio. A quantificação das respostas se efetuou por meio da medição dos valores de peso úmido e seco e do cálculo, a partir destes, do conteúdo de água, como variável derivada indicativa do equilíbrio hídrico. A análise estatística foi realizada usando análise univariada e multivariada. As larvas conseguiram sobreviver em soluções eletrolíticas e não eletrolíticas até 200 mOsm. A função discriminante foi a melhor ferramenta para descrever as respostas dos animais ao estresse osmótico ambiental. Os resultados foram comparados com os obtidos em estudos anteriores, usando um protocolo de exposição aguda aos mesmos meios de incubação usados neste estudo. Concluiu-se: a) a análise multivariada é a aproximação adequada para descrever as respostas das larvas às mudanças nos parâmetros físico-químicos do seu meio; e b) tanto a aclimatação progressiva, como as exposições agudas às soluções experimentais induziram as respostas semelhantes.
Subject(s)
Animals , Bufonidae/physiology , Water-Electrolyte Balance/physiology , Bufonidae/metabolism , Larva/metabolism , Larva/physiology , Osmolar Concentration , Time FactorsABSTRACT
Toad poisoning is frequent in dogs, but has been infrequently addressed in published case reports and review articles. Dogs can be poisoned when they bite a toad or otherwise ingest the venom. The venom effects manifest soon after the accident, since the toxin is rapidly absorbed by the mucous membrane of the digestive system. Hospital records of three dogs, diagnosed with toad poisoning, were retrospectively reviewed from January 2005 to July 2007. Poisoned dogs may present only local irritation or systemic signs in the gastrointestinal, cardiac and neurological systems. All three cases presented herein had clinical signs of gastrointestinal alterations including vomiting, sialorrhea and diarrhea. Two dogs developed abnormal cardiac rhythm and two exhibited neurological signs. A poisoned animal requires emergency care and symptomatic therapy with intense monitoring of its clinical parameters. Although there have been reports on the low mortality of dogs poisoned by toads, one animal died even after appropriate therapy. The severity of clinical signs and the risk of death must be considered by the veterinarian.(AU)
Subject(s)
Animals , Male , Female , Amphibian Venoms/toxicity , DogsABSTRACT
Toad poisoning is frequent in dogs, but has been infrequently addressed in published case reports and review articles. Dogs can be poisoned when they bite a toad or otherwise ingest the venom. The venom effects manifest soon after the accident, since the toxin is rapidly absorbed by the mucous membrane of the digestive system. Hospital records of three dogs, diagnosed with toad poisoning, were retrospectively reviewed from January 2005 to July 2007. Poisoned dogs may present only local irritation or systemic signs in the gastrointestinal, cardiac and neurological systems. All three cases presented herein had clinical signs of gastrointestinal alterations including vomiting, sialorrhea and diarrhea. Two dogs developed abnormal cardiac rhythm and two exhibited neurological signs. A poisoned animal requires emergency care and symptomatic therapy with intense monitoring of its clinical parameters. Although there have been reports on the low mortality of dogs poisoned by toads, one animal died even after appropriate therapy. The severity of clinical signs and the risk of death must be considered by the veterinarian.