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1.
Ecotoxicology ; 28(9): 1105-1114, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31587130

RESUMEN

Pyrethroid insecticides are one of the most commonly used pesticide groups, but these compounds have brought risks to non-target species, such as amphibians. This study evaluated the toxicological effects (mortality, swimming activity and oral morphology) caused to a South American species of anuran amphibian, Physalaemus gracilis, exposed to the pyrethroids cypermethrin and deltamethrin. Total spawnings of this anuran were collected in the natural environment and transported to the laboratory where they were kept under controlled conditions. Chronic assays were defined between 0.1 and 0.01 mg L-1 of cypermethrin, and 0.009 and 0.001 mg L-1 of deltamethrin. For cypermethrin, a further chronic toxicity test was performed at 0.05 and 2.0 mg L-1, with hatchlings at stages S.20-S.25. Cypermethrin and deltamethrin were lethal enough to kill over 70% of exposed tadpoles in 1 week at concentrations that can be found in nature (0.01-0.1 mg L-1). The exposure effects also influenced swimming activity and caused changes in oral morphology, which would make it difficult for the animals to survive in their natural habitat. Both pyrethroids presented a risk for P. gracilis, so they should be re-evaluated for non-target wild species.


Asunto(s)
Anuros/fisiología , Insecticidas/toxicidad , Nitrilos/toxicidad , Piretrinas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Larva/efectos de los fármacos , Larva/fisiología , Pruebas de Toxicidad Crónica/veterinaria
2.
Ecology ; 99(11): 2625, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30229895

RESUMEN

Mortality from collision with vehicles is the most visible impact of road traffic on wildlife. Mortality due to roads (hereafter road-kill) can affect the dynamic of populations of many species and can, therefore, increase the risk of local decline or extinction. This is especially true in Brazil, where plans for road network upgrading and expansion overlaps biodiversity hotspot areas, which are of high importance for global conservation. Researchers, conservationists and road planners face the challenge to define a national strategy for road mitigation and wildlife conservation. The main goal of this dataset is a compilation of geo-referenced road-kill data from published and unpublished road surveys. This is the first Data Paper in the BRAZIL series (see ATLANTIC, NEOTROPICAL, and BRAZIL collections of Data Papers published in Ecology), which aims make public road-kill data for species in the Brazilian Regions. The dataset encompasses road-kill records from 45 personal communications and 26 studies published in peer-reviewed journals, theses and reports. The road-kill dataset comprises 21,512 records, 83% of which are identified to the species level (n = 450 species). The dataset includes records of 31 amphibian species, 90 reptile species, 229 bird species, and 99 mammal species. One species is classified as Endangered, eight as Vulnerable and twelve as Near Threatened. The species with the highest number of records are: Didelphis albiventris (n = 1,549), Volatinia jacarina (n = 1,238), Cerdocyon thous (n = 1,135), Helicops infrataeniatus (n = 802), and Rhinella icterica (n = 692). Most of the records came from southern Brazil. However, observations of the road-kill incidence for non-Least Concern species are more spread across the country. This dataset can be used to identify which taxa seems to be vulnerable to traffic, analyze temporal and spatial patterns of road-kill at local, regional and national scales and also used to understand the effects of road-kill on population persistence. It may also contribute to studies that aims to understand the influence of landscape and environmental influences on road-kills, improve our knowledge on road-related strategies on biodiversity conservation and be used as complementary information on large-scale and macroecological studies. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.

3.
Homeopathy ; 105(3): 250-256, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27473546

RESUMEN

BACKGROUND: As a therapeutic system, homeopathy is supported by: i) similitude and experimentation in healthy individuals, ii) potentization. A challenge for researchers consists in looking for signals in water (or vehicle) to explain the storage of information in extremely high dilutions and the transfer of such information to the living systems. Anuran amphibian metamorphosis is controlled by thyroid hormones (TH), including the resorption of the tadpole tail. Apoptosis is a genetically regulated form of cell death that can be triggered by various extracellular and intracellular stimuli resulting in coordinated activation of a family of cysteine proteases called caspases. METHODS: This study was blind and randomized. It performed in three stages: I) the identification of the most effective T3 homeopathic dilution to induce apoptotic reactions in Rana (Lithobates) catesbeianus tadpole tail explants stimulated by T3 in substantial, II) study of different controls and III) detection in explants under the action of the most effective dilution of T3, as established in Stage I. RESULTS: There was no statistically significant difference between tail macroscopic dimensions between the groups. T3 10cH decreased the expression of caspase 3/7 mRNA, in explants treated with T3 20 nM. CONCLUSION: The present experiment is in agreement with the hypothesis that T3, at a 10cH homeopathic dilution, changes the metamorphosis molecular network.


Asunto(s)
Apoptosis/efectos de los fármacos , Larva/efectos de los fármacos , Materia Medica/química , Metamorfosis Biológica/efectos de los fármacos , Triyodotironina/farmacología , Animales , Homeopatía , Técnicas de Cultivo de Órganos , Rana catesbeiana , Cola (estructura animal)/efectos de los fármacos
4.
J Environ Sci Health B ; 50(12): 896-900, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26266476

RESUMEN

In order to avoid that contaminated frog farms animals escaping in the environment and become potential vector of emergent diseases, studies with disinfection protocol are strictly necessary. The formaldehyde is one of the compounds tested in fungal disinfection protocols and also used in aquaculture. This study aimed to determine the median lethal concentration (LC50-96h) of formaldehyde in bullfrog tadpoles and to evaluate the possible genotoxic effects in acute exposition. Accordingly, the animals were exposed to formaldehyde in the concentrations of 6, 9, 12, 15, and 18 mg L(-1), and after 96 h blood samples were drawn for the micronucleus (MN) test. The LC50-96h was 10.53 mg L(-1), and the MN frequency increased in proportion to the formaldehyde concentrations, with an estimated frequency in the negative control being 1.35 MN/individual. We concluded that formaldehyde is genotoxic to tadpoles of bullfrogs in the tested concentrations, and the choice of this chemical should be contemplated before its use in animals in captivity.


Asunto(s)
Formaldehído/toxicidad , Mutágenos/toxicidad , Rana catesbeiana/metabolismo , Contaminantes Químicos del Agua/toxicidad , Animales , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Dosificación Letal Mediana , Pruebas de Micronúcleos , Rana catesbeiana/crecimiento & desarrollo
5.
Rev. colomb. cienc. pecu ; 33(4): 264-272, Oct.-Dec. 2020. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1376897

RESUMEN

Abstract Background: Tropical grasses, such as elephant grass, have high moisture content during its ideal phenological state for silage. High moisture content hinders proper preservation and reduces the nutritive value of silage due to secondary fermentation and production of effluents. Adding feed materials with high dry matter content, such as murumuru (Astrocaryum murumuru) meal, is a potential alternative to improve silage yield. Objective: To determine the effects of including murumuru meal (0, 7, 14, 21, and 28%) on the fermentative characteristics, microbiological activity, aerobic stability, and chemical composition of elephant grass silages. Methods: A completely randomized design with five treatments and five replicates was used. Elephant grass was collected at 60 d of age, minced, and homogenized with murumuru meal. The mass was placed in experimental 15-L silos. The silos were collected and analyzed 45 d later. Results: Effluent production decreased (p<0.05) as the proportions of murumuru meal in silage increased. A quadratic effect (p<0.05) was observed on dry matter recovery. An increase (p<0.05) was observed in dry matter content, a decrease (p<0.05) in the neutral detergent fiber content, and an increase (p<0.05) in the non-fibrous carbohydrate content with the inclusion of murumuru meal. Conclusions: Addition of murumuru meal improves chemical composition and does not affect the fermentative characteristics of elephant grass silage, while it reduces effluent losses. Nevertheless, the inclusion of murumuru meal in the elephant grass silage decreased the time of aerobic stability.


Resumen Antecedentes: los pastos tropicales, tales como el pasto elefante, tienen alto contenido de humedad cuando están en su estado fenológico ideal para ensilar. Esto dificulta su adecuada preservación en el silo, reduciendo el valor nutritivo del ensilaje debido a fermentaciones secundarias y generación de efluentes. Una posible solución sería incluir materiales con alto contenido de materia seca, tales como la torta de murumuru (Astrocaryum murumuru). Objetivo: determinar el efecto de la inclusión de torta de murumuru (0; 7; 14; 21 y 28%) sobre las características fermentativas, microbiológicas, estabilidad aeróbica y composición química de los ensilajes de pasto elefante. Métodos: se utilizó un diseño completamente al azar, con cinco tratamientos y cinco repeticiones. El pasto elefante fue colectado a los 60 días de edad, luego picado y homogeneizado con la torta de murumuru. La masa fue colocada en silos experimentales con capacidad de 15 L. Luego de 45 días de ensilado, los silos fueron abiertos y las muestras fueron colectadas para su posterior análisis. Resultados: hubo reducción (p<0,05) en la producción de efluentes a medida que se incrementó la proporción de torta de murumuru en el ensilado. Se observó un efecto cuadrático (p<0,05) en la recuperación de materia seca. Hubo aumento (p<0,05) en los contenidos de materia seca con la adición de torta de murumuru. Se observó disminución (p<0,05) en el contenido de fibra detergente neutra y aumento (p<0,05) de carbohidratos no fibrosos. Conclusión: La adición de torta de murumuru mejora la composición química, reduce las perdidas por efluentes y no afecta las características fermentativas de ensilado de pasto elefante. Sin embargo, la inclusión de la torta de murumuru en el ensilado de pasto elefante disminuye el tiempo en estabilidad aeróbica.


Resumo Antecedentes: capins tropicais, como por exemplo o capim-elefante apresentam alto teor de umidade quando possuem produtividade compatível e estão no estádio fenológico adequado para ensilagem. Isso dificulta a adequada preservação no silo, ocasionando a redução do valor nutritivo da silagem devido a fermentações secundárias e a produção de efluentes. Uma possível solução seria o uso de aditivos com alto teor de matéria seca, como bolo de murumuru (Astrocaryum murumuru). Objetivo: determinar o efeito da inclusão da torta de murumuru (0; 7; 14; 21 e 28%) na ensilagem de capim-elefante sobre as características fermentativas, microbiológicas, estabilidade aeróbia e a composição química das silagens. Métodos: utilizou- se um delineamento inteiramente casualizado, com cinco tratamentos e cinco repetições. O capim-elefante foi colhido aos 60 dias de idade, o mesmo foi picado e homogeneizado à torta de murumuru. A massa foi ensilada em silos experimentais com capacidade de 15 L. Após 45 dias de ensilagem, os silos foram abertos e amostras foram coletadas para posteriores análises laboratoriais. Resultados: houve redução (p<0,05) na produção de efluentes à medida que se elevaram as proporções da torta de murumuru na ensilagem. Observou-se efeito quadrático (p<0,05) na recuperação de matéria seca. Houve aumento (p<0,05) nos teores de matéria seca com a adição da torta murumuru. Observou-se diminuição (p<0,05) nos teores de fibra em detergente neutro e aumento (p<0,05) nos teores de carboidratos não fibrosos. Conclusão: torta de murumuru como aditivo melhora a composição química, reduz perdas principalmente por efluente e não afeta as características fermentativas de silagens de capim- elefante. Entretanto, a inclusão da torta de murumuru na ensilagem de capim-elefante diminui o tempo em estabilidade aeróbia.

6.
J Aquat Anim Health ; 22(2): 123-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20848887

RESUMEN

There is generally a dearth of information involving reference ranges of health variables for numerous elasmobranch species commonly housed in zoos and aquaria; thus, extrapolation from a few existing elasmobranch studies is commonly used to assess health parameters in these species. The primary objective of this study was to establish baseline complete blood cell count and plasma chemistry reference ranges for captive individuals of the cownose ray Rhinoptera bonasus, an elasmobranch that is widely displayed in zoos and aquaria worldwide. This study was conducted using 18 adult cownose rays currently housed at the Mystic Aquarium and Institute for Exploration in Connecticut. Median blood and plasma values were 550 cells/microL for total white blood cell count; 511,250 cells/microL for total red blood cell count; 31% for packed cell volume; 5.8 g/L for total solids; 2.85 g/dL for total protein; 33 units (U)/L for aspartate aminotransferase; 34 U/L for alkaline phosphatase; 0.2 mg/dL for total bilirubin; 1,155 mg/dL for urea nitrogen; 0.1 mg/dL for creatinine; 0.6 g/dL for albumin; 2.15 g/dL for globulins; 144 mg/dL for cholesterol; 157 mg/dL for triglycerides; 45 mg/dL for glucose; 16.9 mg/dL for calcium; 5.8 mg/dL for phosphorus; 294 mmol/L for sodium; 1.55 mmol/L for potassium; and 270 mmol/L for chloride. Gamma glutamyl transpeptidase, amylase, creatine kinase, and lactate dehydrogenase were below the detectable limits for several samples. In nine samples, alanine aminotransferase levels were below the instrument range (< 4 U/L). No significant differences between sexes were detected. The reference ranges reported in this study should provide a useful guide for routine health monitoring of captive cownose rays.


Asunto(s)
Análisis Químico de la Sangre/veterinaria , Rajidae/sangre , Equilibrio Ácido-Base , Animales , Glucemia/análisis , Proteínas Sanguíneas/análisis , Electrólitos/análisis
7.
Pesqui. vet. bras ; 34(4): 369-373, abr. 2014. tab
Artículo en Inglés | LILACS | ID: lil-712727

RESUMEN

The aim of this study was to evaluate alterations to the physiological profile of cortisol in pro-metamorphose phase tadpoles of Lithobates catesbeianus exposed to hypoxia stressor in a capture experiment and in a crowding experiment. The capture study was performed by the treatments: stress due to individual capture with a hand net, stress due to batch capture with a hand net and stress due to capture by emptying. Three simultaneous replicates was done witch 12 animals were sampled (6 normoxia - immediately blood collection) and 6 hypoxia - blood collection after 15 min of air exposition) in two collection times with 5 days by intervals. The crowding study was performed by the treatments 1 tadpole L-1, 5 tadpoles L-1 and 10 tadpoles L-1. Three simultaneous replicates was done witch 8 animals (4 normoxia and 4 hypoxia) were sampled in the zero moment (ZM) - blood collection before the experiment, 6 animals/treatment (3 normoxia and 3 hypoxia) to 4 and 8 days and 18 animals/treatment (9 normoxia and 9 hypoxia) to 12 days. The average values to plasmatic cortisol varying from 1.7 to 5.1ng mL-1 (capture study) and 1.0 to 4.2ng mL-1 (crowding study). It concludes that the biomarker tested (cortisol) showed no alterations front of the stressor used. Alternatively, a larger response pattern to these stimuli may have been expressed in another level of an unmeasured hormone (corticosterone). And the bullfrog has great ability to adapt to different management compared to other aquatic organisms, which demonstrates the plasticity of these animals.


Avaliou-se o cortisol em girinos de rã-touro (Lithobates catesbeianus), no estágio de pró-metamorfose ao mecanismo estressor de hipóxia juntamente com captura (1º experimento) e adensamento (2º experimento). O experimento de captura foi composto pelos tratamentos: Captura individual com puçá, Captura em massa com puçá e Captura por escoamento, com 3 réplicas simultâneas onde 12 organismos foram amostrados (6 normoxia - coleta imediata de sangue e 6 hipoxia - coleta de sangue após 15 min de exposição ao ar) em 2 tempos de coleta com intervalo de 5 dias. O experimento de densidade foi composto pelos tratamentos: 1 girino L-1, 5 girinos L-1 e 10 girinos L-1, com 3 réplicas simultâneas onde 8 animais (4 normoxia e 4 hipoxia) foram amostrados no momento zero (MZ) - coleta de sangue anterior ao experimento, 6 animais/tratamento (3 normoxia e 3 hipoxia) para 4 e 8 dias e 18 animais/tratamento (9 normoxia e 9 hipoxia) para 12 dias. Os valores médios para o cortisol plasmático foram de 1,7 a 5,1ng mL-1 (Experimento de Captura); e 1,0 a 4,2ng mL-1 (Experimento de Densidade). Conclui-se que o marcador biologico de estresse utilizado (cortisol) não foi alterado pelo agente extressor. Alternativamente a resposta a este estímulo pode ser expressa em outro nível hormonal (corticosterona). E a rã-touro apresenta ótima capacidade de se adaptar aos diferentes manejos se comparados a outros organismos aquáticos, o que demonstra a plasticidade destes animais.


Asunto(s)
Animales , Hipoxia/veterinaria , Estrés Fisiológico/fisiología , Hidrocortisona/análisis , Larva/crecimiento & desarrollo , Rana catesbeiana/fisiología , Hipoxia/complicaciones , Corticosterona , Densidad de Población
8.
Pesqui. vet. bras ; 30(10): 891-896, out. 2010. tab
Artículo en Inglés | LILACS | ID: lil-567929

RESUMEN

The American bullfrog (Rana catesbeiana), recently named Lithobates catesbeianus is currently farmed for commercial purposes throughout various regions of Brazil. Stressful situations such as problems of management, inadequate facilities and environmental changes with consequent reduction of immunity are common in intensive production. The assessments of these situations of stress allow us detect these problems decreasing the injuries causes by confinement. The main objective of this study was to use the biological markers of plasma cortisol and glucose level and hematological parameters to evaluate the response of bullfrog tadpoles submitted to stressed mechanisms of capture and hypoxia. The animals were subjected to three treatments: stress due to individual capture with a hand net; stress due to batch capture with a hand net; and stress due to capture by emptying. The results obtained demonstrated that there were no statistically significant differences in the parameters tested when comparing the treatments with and without exposure to air (normoxia and hypoxia). Based on these results we can conclude that the stressful stimuli tested were not adequate to alter the biomarker tested. For the cortisol, probably this should have occurred due to the synergistic action between this hormone and thyroxin, which induces metamorphosis in these animals.


A rã-touro americana (Rana catesbeiana) recentemente denominada Lithobates catesbeianus é cria da com propósito comercial em várias regiões do Brasil. Situações estressantes tais como problemas de manejo, criação inadequada e alterações ambientais com consequente redução da imunidade são comuns em produções intensivas. A avaliação destas situações de estresse permite-nos detectar estes probemas e diminuir as injurias causadas pelo confinamento. O principal objetivo deste estudo foi utilizar os marcadores biológicos de cortisol, glicemia e dados hematológicos para avaliar a resposta de girinos de rã-touro submetidos aos mecanismos estressores de captura e hipóxia. Os animais foram distribuídosem três tratamentos: estresse por captura individual com puçá; estresse por captura em massa com puçá e estresse por captura por escoamento. Os resultados obtidos demostraram não haver diferenças estatisticamente significativas entre os parametros avaliados quando comparou-se os grupos com e sem exposição ao ar (normoxia e hipoxia). Com base nestes resultados pode-se concluir que os estímulos estressores avaliados não foram adequados para alterar os valores plasmáticos dos marcadores biológicos testados. Para o cortisol, isto ocorreu provavelmente em virtude da ação sinérgica deste hormônio e a tiroxina, que induz a metamorfose nestes animais.


Asunto(s)
Animales , Anfibios/anomalías , Anfibios/fisiología , Anfibios/sangre , Trastornos de Estrés Traumático/diagnóstico
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