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1.
Int J Food Microbiol ; 331: 108628, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32535523

RESUMO

A mycotoxicological survey was conducted in breakfast (n = 172) and infant (n = 43) cereals commercialized in Brazil. Samples were collected in 2018 for analyses of: aflatoxins (AFs) B1 (AFB1), B2, G1 and G2; fumonisins (FBs) B1 (FB1) and B2; zearalenone (ZEN); the trichothecenes (TRCs) deoxynivalenol (DON), T-2 toxin, HT-2 toxin, nivalenol, fusarenon X, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol and diacetoxyscirpenol; and ochratoxin A. FB1 was the most prevalent metabolite in breakfast cereals, being detected in 26.7% of the samples (mean 105 µg/kg); ZEN had the second highest positivity, 14.8% (mean 17 µg/kg), followed by DON with 10% (mean 44 µg/kg). In infant cereals, FB1 also had the highest incidence, 27.8% (mean 55 µg/kg), followed by DON with 10.3% (mean 36 µg/kg) and ZEN with 6.9% (mean 3 µg/kg). Mycotoxins contamination was found in 31.4% (n = 54) of the breakfast cereals and in 18.6% (n = 8) of the infant cereals. In these positive samples, co-occurrence of two or three mycotoxins was detected in 31.5% (n = 17) of the breakfast cereals and in 25% (n = 2) of the infant cereals. The mycotoxins found co-contaminating the breakfast cereals belong to the genera Aspergillus and Fusarium; ZEN, followed by AFB1, were the most prevalent ones. As for the infant cereals, the associated fungal metabolites are produced by the genus Fusarium; the highest incidence was seen for ZEN. Low contamination and positivity of mycotoxins were found herein; nonetheless, in some samples these substances were present at levels which transgress those preconized in the Brazilian legislation. Therefore, mycotoxicological monitoring of this type of product throughout the nation is crucial in order to identify the potential risk to which the Brazilian population is exposed, particularly the children.


Assuntos
Desjejum , Grão Comestível/química , Contaminação de Alimentos/análise , Micotoxinas/análise , Brasil , Criança , Humanos , Lactente
2.
Res Vet Sci ; 117: 150-160, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29275218

RESUMO

The effects of pre-transport handling and addition of essential oil of Myrcia sylvatica (EOMS) during transport on stress pathways activation in Rhamdia quelen were investigated. Fish (n=400, 25.2±2.9g) were captured in production ponds and transferred to 100-L tank (density 100g L-1). After 24h, 10 fish were sampled (before transport group). The remaining fish were placed in plastic bags (n=30 or 32 fish per bag, density 150g L-1) containing 5L of water (control), ethanol (315µLL-1, vehicle) or EOMS (25 or 35µLL-1), in triplicate, transported for 6h and sampled (n=10 animals per group). Indicators of stress and metabolism, as well as mRNA expression of brain hormones were evaluated. Previously, full-length cDNAs, encoding specific corticotropin-releasing hormone (crh) and proopiomelanocortins (pomca and pomcb), were cloned from whole brain of R. quelen. Crh expression increased after 24h of capture and handling, whereas cortisol and glucose plasmatics enhanced their values in the control group. Transport with EOMS reduced plasma cortisol and lactate levels, while ethanol and EOMS groups increased Na+/K+-ATPase gill activity compared to control. Gene expression of crh, pomcb, prolactin and somatolactin mRNAs were lower after transport with EOMS compared to control. EOMS was able to mitigate the stress pathways activation caused by transport, maintaining a balance in body homeostasis. Thus, EOMS is recommended as sedative in procedures as transport and the pre-transport handling requires greater attention and use of tranquilizers.


Assuntos
Peixes-Gato , Hipnóticos e Sedativos/farmacologia , Óleos Voláteis/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Animais , Peixes-Gato/metabolismo , Peixes-Gato/fisiologia , Brânquias , Hidrocortisona , Meios de Transporte
3.
Vet Anaesth Analg ; 44(3): 555-566, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28566223

RESUMO

OBJECTIVE: To investigate the effects of rapid anesthesia and long-term sedation with the essential oils (EOs) of Myrcia sylvatica (EOMS) and Curcuma longa (EOCL) on biochemical and oxidative parameters in matrinxã. STUDY DESIGN: Prospective, randomized, laboratory experiment. ANIMALS: A total of 72 matrinxã (Brycon amazonicus) adults weighing 404.8 ± 27.9 g were divided into eight groups of nine fish. METHODS: Biochemical and oxidative effects were investigated in plasma and tissues of matrinxã subjected to rapid anesthesia (5 minutes) or long-term sedation (360 minutes, simulating the practice of transport) with EOMS (200 µL L-1 and 10 µL L-1, respectively) and EOCL (500 µL L-1 and 40 µL L-1, respectively). RESULTS: Transport simulation without sedation or anesthesia increased lipid peroxidation levels in the gills and kidney of fish in the control group. Anesthesia and sedation with EOs decreased cortisol concentrations and increased lactate concentrations compared with controls. Lipid peroxidation was lower in the brain, gills, liver and kidney of sedated and anesthetized fish, than in the control group. Anesthesia with EOs increased the activity of superoxide dismutase and glutathione-S-transferase in the brain, and catalase in the liver and gills, compared with controls. Long-term sedation with EOs increased superoxide dismutase, glutathione peroxidase and glutathione reductase activities in the brain, catalase in the liver, glutathione peroxidase and glutathione reductase in the gills and superoxide dismutase in the kidney. In general, nonprotein thiols content and total reactive antioxidant potential of tissues were higher after anesthesia and sedation with EOs compared with the control group. CONCLUSIONS AND CLINICAL RELEVANCE: The concentrations of EOMS and EOCL used were effective at preventing a stress response and excess of reactive oxygen species formation. For these reasons, these substances may be recommended for use in the transportation of fish to improve survival and animal welfare.


Assuntos
Anestésicos/farmacologia , Caraciformes/metabolismo , Curcuma/química , Peroxidação de Lipídeos/efeitos dos fármacos , Myrtaceae/química , Óleos Voláteis/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Meios de Transporte , Animais , Encéfalo/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Peroxidação de Lipídeos/fisiologia , Fígado/metabolismo , Óleos Voláteis/administração & dosagem , Estudos Prospectivos , Distribuição Aleatória , Manejo de Espécimes/métodos , Manejo de Espécimes/veterinária , Estresse Fisiológico , Superóxido Dismutase/metabolismo
4.
J Exp Zool A Ecol Integr Physiol ; 327(8): 504-512, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29356428

RESUMO

The effect of dissolved organic carbon (DOC) against the burden of low pH was assessed in silver catfish Rhamdia quelen through the gills. A commercial humic acid (HA) was used as the source of DOC at 0 (control), 10, 25, and 50 mg/l. For each HA concentration, two pH levels were tested: 6.5 (control) and 5.5. After 40 days of exposure, the gills were removed and morphological variables were analyzed through light and scanning electronic microscopy. The low water pH caused a reduction in the length of filaments, number of lamellae, and gill respiratory surface area (GRSA) and an increase in chloride cells (CCs) number in the filament epithelium. When HA was added to the test water, GRSA increased and CCs proliferated in lamellae, suggesting ionic and respiratory disturbances. Scanning electronic microscopy revealed that CC morphometric variables, that is, apical area, fractional area, and density, were undisturbed by the pH reduction, but increased in the presence of HA. This study indicates that the commercial HA did not protect silver catfish against low pH stress. Instead, it caused changes that may affect vital processes such as ion regulation and ventilation and, consequently, reduce growth.


Assuntos
Peixes-Gato , Brânquias/efeitos dos fármacos , Água/química , Animais , Brânquias/ultraestrutura , Substâncias Húmicas , Concentração de Íons de Hidrogênio
5.
Neotrop. ichthyol ; 15(1): e160076, 2017. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-841874

RESUMO

This study evaluated anesthetic efficacy and possible effects of the essential oils (EOs) of Cunila galioides (EOC) and Origanum majorana (EOO) on ventilatory rate (VR) and ionoregulation in Rhamdia quelen. In the anesthesia assessments, 50, 100, 200 and 300 μL L-1 EOC and 50, 100, 200, 300, 400 and 500 μL L-1 EOO were tested, and time for induction to sedation and anesthesia stages, as well as recovery, were taken. A second trial employed lower concentrations of both EOs, 10, 25, 50 and 100 μL L-1, in order to verify VR and Na+, K+ and Cl- whole body net fluxes. Sedation was achieved with both oils at 100 µL L-1, and anesthesia at ≥ 200 µL L-1. There was no significant difference between control and EO-treated groups regarding VR, but all fish subjected to 100 µL L-1 EOC died within 2 h of exposure. Overall, ionic loss declined in the presence of the EOs. The EOC at 200 - 300 μL L-1 and EOO at 400 - 500 μL L-1 present the potential to promote fast anesthesia in R. quelen.(AU)


No presente estudo foi avaliada a eficácia da anestesia e possíveis efeitos dos óleos essenciais (EOs) de Cunila galioides (EOC) e Origanum majorana (EOO) sobre a taxa ventilatória (VR) e regulação iônica em Rhamdia quelen. Nas avaliações de anestesia, as concentrações de 50, 100, 200 e 300 μL L-1 EOC e 50, 100, 200, 300, 400 e 500 μL L-1 EOO foram testadas, e os tempos para a indução às fases de sedação e de anestesia, assim como recuperação, foram mensurados. Um segundo ensaio empregou concentrações mais baixas de ambos EOs: 10, 25, 50 e 100 μL L-1 a fim de verificar a VR e o fluxo líquido corporal dos íons Na+, K+ and Cl- . A sedação foi alcançada para ambos os óleos em 100 μL L-1, e a anestesia em concentrações ≥ 200 µL L-1. Não houve diferença significativa entre o controle e grupos tratados com EOs em relação a VR, mas todos os peixes submetidos a 100 µL L-1 do EOC morreram dentro de 2 h de exposição. No geral, a perda iônica declinou na presença dos EOs. O EOC em 200 - 300 μL L-1 e o EOO em 400 - 500 μL L-1 apresentam potencial para anestesia rápida em R. quelen.(AU)


Assuntos
Animais , Anestésicos/administração & dosagem , Peixes-Gato/imunologia , Óleos Voláteis/síntese química
6.
Fish Physiol Biochem ; 42(1): 321-33, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26468115

RESUMO

The effects of adding rutin to the diet (0, 0.15 or 0.30%) of silver catfish for 21 days on blood parameters, oxidative stress biomarkers and pituitary hormones expression were investigated. Fish that received the diet containing 0.15% rutin exhibited reduced plasma cortisol levels. The levels of lipid peroxidation were lowered in the all tissues of animals receiving the diet containing rutin. Rutin increased the activity of the superoxide dismutase (SOD), catalase (CAT), nonprotein thiols (NPSH), ascorbic acid content (AA) and total reactive antioxidant potential (TRAP) in the brain; glutathione S-transferase (GST) activity and TRAP in the gills; SOD, CAT and GST activity, NPSH, AA levels and TRAP in the liver; CAT and GST activity and TRAP levels in the kidneys; and glutathione peroxidase activity, NPSH, AA levels and TRAP in the muscle. There were no changes regarding the expression of growth hormone, prolactin and somatolactin in fish fed with the diet containing rutin when compared with the control. The supplementation of rutin to the diet of fish is beneficial because it increases the antioxidant responses of tissues.


Assuntos
Peixes-Gato , Estresse Oxidativo/efeitos dos fármacos , Rutina/farmacologia , Animais , Biomarcadores/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Catalase/metabolismo , Peixes-Gato/sangue , Peixes-Gato/genética , Peixes-Gato/metabolismo , DNA Complementar/genética , Dieta , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Hidrocortisona/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Fenóis/análise , Hormônios Hipofisários/genética , RNA Mensageiro/metabolismo , Superóxido Dismutase/metabolismo
7.
Neotrop. ichthyol ; 13(4): 707-714, Oct.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769845

RESUMO

The aim of this study was to evaluate the effect of the essential oil of Lippia alba (EOLA) as a feed additive on ionoregulatory and metabolic parameters and pituitary hormones expression in silver catfish, Rhamdia quelen , submitted to a stressful condition (stocking density of 10.6 kg m-3 and limited space). Fish were fed with different concentrations of EOLA (0.0 - control, 0.25 and 0.50 mL kg food-1) for 20 days. Metabolic parameters were not affected by the diet, with the exception of alanine aminotransferase, which was higher in the liver of fish fed 0.50 mL EOLA kg food-1. Plasma ions and activity of H+-ATPase did not change, but fish fed 0.25 mL EOLA kg food-1 presented higher Na+/K+-ATPase activity. Somatolactin expression in the pituitary was higher in the fish fed 0.25 mL EOLA kg food -1, but the expression of growth hormone and prolactin did not change. Therefore, dietary EOLA does not exert a protective effect in R. quelen submitted to a stressful situation because it did not alter most measured parameters. The use of 0.25 mL EOLA kg food-1 seems to be more suitable than 0.50 mL EOLA kg food-1 since the latter may be related to liver damage.


O objetivo deste estudo foi avaliar o efeito do óleo essencial de Lippiaalba (OELA) como aditivo em rações na ionoregulação, parâmetros metabólicos e expressão de hormônios hipofisários em jundiás, Rhamdiaquelen, submetidos a uma situação estressante (densidade de estocagem de 10,6 kg m-3 e espaço limitado). Os peixes foram alimentados com diferentes concentrações de OELA (0,0 - controle, 0,25 e 0,50 mL kg de ração-1) durante 20 dias. Parâmetros metabólicos não foram afetados pela dieta, com a exceção da alanina aminotransferase, que foi mais elevada no fígado dos peixes alimentados com 0,50 mL de OELA kg de ração-1. Íons plasmáticos e a atividade da H+-ATPase não apresentaram nenhuma alteração, mas os peixes alimentados com 0,25 mL OELA kg de ração-1 apresentaram maior atividade da Na+/K+-ATPase. A expressão da somatolactina na hipófise de peixes alimentados com 0,25 mL OELA kg de ração-1 aumentou, porém a expressão do hormônio de crescimento e da prolactina não mudou. Portanto, a adição do OELA na ração não tem um efeito protetor em jundiás submetidos a uma situação estressante, pois não influiu na maioria dos parâmetros medidos. O uso de 0,25 mL OELA kg de ração-1 parece ser mais adequado que 0,50 mL OELA kg de ração-1, uma vez que este nível de inclusão pode estar relacionado a danos hepáticos.


Assuntos
Animais , Óleos Voláteis/administração & dosagem , Óleos Voláteis/análise , Óleos Voláteis/efeitos adversos , Ração Animal/análise
8.
J Comp Physiol B ; 184(4): 469-82, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24526310

RESUMO

Aquatic animals are naturally exposed simultaneously to environments with different concentrations of humic acid (HA) and seasonal or daily variations of dissolved oxygen (DO) levels. This study investigated the effects of simultaneous exposure to different HA and DO levels on plasma ion levels and some hematological and oxidative parameters in different tissues of silver catfish (Rhamdia quelen). The fish were exposed to 0, 2.5 or 5 mg L(-1) HA for 120 h. After this period, each group was divided into two groups: normoxia and hypoxia. Exposure to the different DO levels lasted 96 h, totaling 216 h of experimentation. At the end of the experimental period, blood sampling was performed, and the fish were euthanized prior to the excision of the gills and the brain to evaluate hematological and oxidative parameters. To verify the antioxidant capacity of HA, total phenolic compounds were measured. In general, all tissues of silver catfish exposed simultaneously to hypoxia and different HA concentrations showed a reduction in lipid peroxidation levels, as well as a modulation of the antioxidant system. These effects occurred in an HA concentration-dependent manner. Thus, HA is beneficial to silver catfish exposed to hypoxia. These beneficial effects can be attributed, most likely, to the action of the different HA constituents and functional groups, including phenolic compounds, which have antioxidant properties.


Assuntos
Encéfalo/fisiologia , Peixes-Gato/fisiologia , Brânquias/fisiologia , Substâncias Húmicas , Hipóxia/fisiopatologia , Medula Espinal/fisiologia , Animais , Relação Dose-Resposta a Droga , Meio Ambiente , Íons/sangue , Peroxidação de Lipídeos/fisiologia , Oxirredução , Fatores de Tempo
9.
Parasitol Res ; 104(2): 485-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19005679

RESUMO

The aim of this research was to study the gastrointestinal parasitism in 12 adult owls kept in captivity in the Southern region of Brazil. Cloacal contents of the species Rhinoptynx clamator, Tyto alba, Athene cunicularia, Megascops spp., and Bubo virginianus were evaluated. Feces and urine were collected and analyzed by the zinc sulfate centrifugal-flotation method and stained by the modified Ziehl-Neelsen technique. Eggs of Capillaria spp. and Strongylida, oocysts of Cryptosporidium spp., Eimeria spp., and Isospora spp. were observed. The birds showed no clinical signs, probably due to the mild nature of the infection.


Assuntos
Trato Gastrointestinal/parasitologia , Parasitos/classificação , Parasitos/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Brasil , Cloaca/parasitologia , Fezes/parasitologia , Feminino , Masculino , Óvulo/citologia , Urina/parasitologia
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