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1.
Ecol Appl ; 34(3): e2950, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38404050

RESUMEN

Forest cover has been a pivotal indicator of biological conservation and carrying capacity for wildlife in forest ecoregions. Such a relationship underpins policies focused on the extension of protected lands. Here, we estimate aboveground biomass (AGB) as a proxy for habitat quality in seminatural rural patches and provide a comparison with approaches that only consider forest cover. We hypothesize that recommendations for biological conservation in agricultural landscapes are substantially improved if habitat quality is also taken into account, and thus consider the possibility of forest quality being modulated by land-use amount, type, and age. We assessed AGB in a densely farmed Brazilian region using a straightforward approach designed to be affordable at large scales, focusing on two expanding and contrasting land uses: sugarcane, and eucalyptus plantations. At a detailed scale, we confirmed through field surveys and AGB estimation using 3D-multispectral imagery (i.e., AGB = 0.842 × vegetation heightNDVI+1) that AGB variation could be predicted with forest degradation classes that are visually distinguishable with high-resolution images: 9.33 t ha-1 (90% predictive intervals [PI] = [3.23, 26.97]) in regenerating fields (RF), 31.12 t ha-1 (90% PI = [10.77, 89.90]) in pioneer woods (PW), and 149.04 t ha-1 (90% PI = [51.59, 430.58]) in dense forests (DF). Applying these values to land units sampled across the study region, we found an average land use of 88.5%, together with 11.5% of land set aside for conservation, which reduced AGB to less than 4.2% of its potential (averages of 5.85 t ha-1 in sugarcane-dominated areas and 6.56 t ha-1 in eucalyptus-dominated areas, with secondary forests averaging 149.04 t ha-1). This imbalance between forest cover and AGB resulted from forest quality decay, which was similarly severe among land-use types, ages, and extensions. Therefore, the shortage of trophic resources is likely more critical to wildlife than spatial limitations in vastly deforested tropical ecoregions, where AGB and carbon sinks can be more than doubled just by restoring forests in lands currently spared by agriculture.


Asunto(s)
Ecosistema , Bosques , Biomasa , Conservación de los Recursos Naturales , Agricultura , Árboles
2.
J Fish Biol ; 102(1): 248-257, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36273252

RESUMEN

The present study compares the trophic ecology of two guitarfishes (Pseudobatos percellens and Pseudobatos horkelii) from the continental shelf of the São Paulo State, Brazil, caught by the bottom pair trawls between 2007 and 2009. These two sympatric species are under different threat categories, "Vulnerable" and "Critically Endangered," respectively, according to Brazilian agencies. Thus, any study considering trophic ecology parameters is pivotal in understanding the trophic ecology role of such species in the ecosystem. The authors analysed 500 stomachs of P. percellens and 108 of P. horkelii, quantifying with dietary indexes: numerical (%N), gravimetric (%W), frequency of occurrence (%FO) and the prey-specific index of relative importance (%PSIRI). For P. percellens and P. horkelii, 26 and 14 different prey items were found, respectively. Crustacea and Teleostei were the most important prey items for both species, indicating a specialist feeding behaviour due to their low niche amplitude. The results provide evidence related to ontogenetic dietary shift in P. percellens and individual-level diet specialization in both species. These two benthic-demersal elasmobranchs are important mesopredators (3,7 for P. percellens, and 3,5 for P. horkelii) in the study area, with high trophic-level values.


Asunto(s)
Ecosistema , Rajidae , Animales , Brasil , Simpatría , Ecología , Estado Nutricional , Conducta Alimentaria , Dieta/veterinaria
3.
Microbiol Spectr ; 10(5): e0128522, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36005767

RESUMEN

Brazil accounted for a total number of 1,276,194 reported cases of chikungunya fever between 2014 and 2022. Additionally, since 2015, the country has experienced an increasing death toll, in which the Northeast and Southeast regions appear to report the worst scenarios. Although the CHIKV transmission dynamics have been studied in many parts of the country since its introduction in 2014, little is still known about chikungunya virus (CHIKV) transmission and genetic diversity in the state of Minas Gerais, located in southeast Brazil. Moreover, no studies have been published characterizing CHIKV genomic surveillance in this state. Thus, to retrospectively explore the CHIKV epidemic in Minas Gerais, we generated 40 genomes from clinical samples using Nanopore sequencing. Phylogenetic analysis indicated that multiple introductions of CHIKV occurred, likely from the northeastern Brazilian states, with the most recent common ancestral strain dating to early March 2016, which is in agreement with local epidemiological reports. Additionally, epidemiological data reveals a decline in the number of reported cases from 2017 to 2021, indicating that population immunity or changes in vector activity may have contributed to the decreasing waves of CHIKV infection. Together, our results shed light on the dispersion dynamics of CHIKV and show that infections decreased from March 2017 to January 2021 despite multiple introductions into Minas Gerais State. In conclusion, our study highlights the importance of combining genomic and epidemiological data in order to assist public health laboratories in monitoring and understanding the patterns and diversity of mosquito-borne viral epidemics. IMPORTANCE Arbovirus infections in Brazil, including chikungunya, dengue, yellow fever, and Zika, result in considerable morbidity and mortality and are pressing public health concerns. However, our understanding of these outbreaks is hampered by the limited availability of genomic data. In this study, we combine epidemiological analysis and portable genome sequencing to retrospectively describe the CHIKV epidemic in Minas Gerais between 2017 and 2021. Our results indicate that the East/Central/South African (ECSA) CHIKV lineage was introduced into Minas Gerais by three distinct events, likely from the North and Northeast regions of Brazil. Our study provides an understanding of how CHIKV initiates transmission in the region and illustrates that genomics in the field can augment traditional approaches to infectious disease surveillance and control.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Infección por el Virus Zika , Virus Zika , Animales , Humanos , Fiebre Chikungunya/epidemiología , Brasil/epidemiología , Estudios Retrospectivos , Filogenia , Virus Chikungunya/genética , Genómica
4.
Sci Total Environ ; 802: 149882, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34464788

RESUMEN

The Doce River mouth (DRM) was severely impacted by the rupture of the Fundão Dam in 2015, considered the greatest Brazilian environmental tragedy in terms of tailings volume released (>40 million m3) and traveled distance (~600 km until the Atlantic Ocean). Environmental monitoring has been performed since then, but background levels are scarce or absent to Persistent Organic Pollutants (POPs), making impact assessments difficult. In the current study, we presented the baseline levels, inventories, and risk assessment of the POPs polychlorinated biphenyl (PCBs) and organochlorinated pesticides (OCPs), in surface sediment of the DRM. Samples were collected in December 2010 and July 2011, i.e., four years before the Fundão dam failure. The total PCBs and the OCPs (Aldrin, HCHs, and Chlordanes) were detected in both sampling campaigns, with levels up to 9.50 and 1.64, 0.28, and 0.63 ng g-1, respectively. The decrease of the Doce River flow was the main factor contributing to seasonal variations in the spatial distribution, and to a slight decline in the levels and frequency of the analyzed POPs in sediments collected in the dry season (July 2011). Environmental risk assessment, inventories, and total mass results suggest a low potential of PCBs and OCPs accumulation before the dam failure. This is the first POPs assessment in the study area that helped identify some unexpected impacts of the Fundão dam failure and contributed to the understanding of POPs cycles in the Southern Atlantic, data that are still scarce in the region.


Asunto(s)
Hidrocarburos Clorados , Plaguicidas , Bifenilos Policlorados , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Hidrocarburos Clorados/análisis , Contaminantes Orgánicos Persistentes , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Ríos , Contaminantes Químicos del Agua/análisis
5.
Zoologia (Curitiba, Impr.) ; 39: e22025, 2022. tab, graf, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1410376

RESUMEN

Altitudinal migration in birds comprises seasonal movements between breeding and non-breeding areas in mountainous regions, attributed to biotic and abiotic factors. Different authors have suggested the existence of altitudinal migration between high and low areas of the mountains of the Atlantic Forest, with movement from high to low during the winter when birds would be fleeing the cold and in search of food, but there is no documented evidence. Through recaptures of understory birds, we investigated possible altitudinal migration in a region of the Atlantic Forest in Southeast Brazil. Twenty mist-nets were set at four locations between 15 and 729 m a.s.l. during 143 days of field work, distributed over 54 months and covering all seasons of the year. A total of 1946 birds (98 species) were captured/banded with 558 being recaptured (28.6%; 45 species). However, only 42 of the recaptures were at a different elevation. Most of the movements were of short distances and performed only once by birds, showing no seasonal pattern. These movements may be better interpreted as daily movements undertaken by birds of mixed-species flocks looking for food or moving around their respective home-ranges. Our results show that mist-nets may not be an effective tool in detecting altitudinal movements of birds and that other methods should be evaluated for this purpose.


Asunto(s)
Animales , Aves , Migración Animal , Sistemas de Identificación Animal , Brasil
6.
Mult Scler Relat Disord ; 50: 102807, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33609926

RESUMEN

BACKGROUND: Studies on the prevalence of neuromyelitis optica spectrum disorder (NMOSD) are still scarce. The aim of the current study was to determine the prevalence rate of NMOSD in Belo Horizonte, southeast Brazil, where the prevalence rate of multiple sclerosis (MS) has already been established. METHODS: For this observational study, eligible patients had to meet the 2015 International Panel for Neuromyelitis Optica Diagnosis, be seen at the study center between January 2000 and February 2019 and live in Belo Horizonte. The prevalence rate of NMOSD was estimated based on the number of MS and NMOSD patients seen at same Center during the same period, and the previously established prevalence of MS in Belo Horizonte. RESULTS: During the study period, there were 69 patients with NMOSD, 60 (87.0%) of whom were females, and 44 (63.8%) non-whites. The median age at disease onset was 36.7 (4-72) years, the mean EDSS score 4.78±2.36, and the mean ARR 0.57±0.43. Anti-aquaporin-4 immunoglobulin testing was available for 61 (88.4%) patients, of whom 41 (67.2%) had a positive result. During the same period, 280 MS patients were seen. Considering the local known prevalence rate of MS of 18.1/100,000 inhabitants, the estimated NMOSD prevalence rate in Belo Horizonte was 4.52/100,000 (95% CI 3.72-5.43) inhabitants. CONCLUSION: The prevalence rate of NMOSD in Belo Horizonte is high as compared with those found in most of the studies reported to date.


Asunto(s)
Esclerosis Múltiple , Neuromielitis Óptica , Acuaporina 4 , Brasil/epidemiología , Femenino , Humanos , Masculino , Esclerosis Múltiple/epidemiología , Neuromielitis Óptica/epidemiología , Prevalencia
7.
Mar Pollut Bull ; 162: 111910, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33338926

RESUMEN

Drought periods may change mangrove litterfall production through water deprivation and increasing tree evapotranspiration, but these impacts have been rarely estimated. In Brazil, an intense drought and strong winds impacted mangrove forests leading to mass tree mortality in 2016, suggesting that forest productivity also declined rapidly. Fifteen months after the initial impact, we started to monitor and quantify litterfall production in paired transects from disturbed and undisturbed mangroves. The litterfall production of the undisturbed forests (575 ± 28 Kg C ha-1 y-1) was 31- to 3-fold higher than that at the disturbed mangrove forests (18 to 169 Kg C ha-1 y-1). The strong decline in litterfall production may have implications to the export of nutrients to estuarine ecosystems. Our baseline suggests that mangrove forests are greatly vulnerable to climate impacts and that the litterfall production collapse in dead mangrove forests may impair marine ecosystem food webs.


Asunto(s)
Ecosistema , Bosques , Brasil , Árboles , Humedales
8.
Mar Environ Res ; 162: 105190, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33137596

RESUMEN

We examined trophic relationships in estuarine planktonic food webs by focusing on the assemblages and functional groups of copepods and their effects on prey and predator. We also studied the relationship between biodiversity and ecosystem functioning in estuaries using different taxonomic and functional diversity indices of copepod assemblages and copepod biomass as a proxy of ecosystem functioning. We collected samples every 2 months over a 2-year period in four Brazilian estuaries. Taxonomic diversity indices showed a positive and negative relationship with chaetognath densities and ecosystem functioning, respectively. The functional indices were negatively related to the effect of predator diversity on prey. Different functional groups of copepods were positively correlated with chaetognath density, consistent with their generalist feeding habits. Thus, multifaceted approaches that use different indices and functional groups are recommended to provide a more realistic view of the trophic relationships and ecosystem functioning in estuaries.


Asunto(s)
Copépodos , Ecosistema , Animales , Biodiversidad , Biomasa , Brasil , Estuarios , Cadena Alimentaria
9.
Emerg Microbes Infect ; 9(1): 1824-1834, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32726185

RESUMEN

The recent emergence of a coronavirus (SARS-CoV-2), first identified in the Chinese city of Wuhan in December 2019, has had major public health and economic consequences. Although 61,888 confirmed cases were reported in Brazil by 28 April 2020, little is known about the SARS-CoV-2 epidemic in this country. To better understand the recent epidemic in the second most populous state in southeast Brazil - Minas Gerais (MG) - we sequenced 40 complete SARS-CoV-2 genomes from MG cases and examined epidemiological data from three Brazilian states. Both the genome analyses and the geographical distribution of reported cases indicate for multiple independent introductions into MG. Epidemiological estimates of the reproductive number (R) using different data sources and theoretical assumptions suggest the potential for sustained virus transmission despite a reduction in R from the first reported case to the end of April 2020. The estimated date of SARS-CoV-2 introduction into Brazil was consistent with epidemiological data from the first case of a returned traveller from Lombardy, Italy. These findings highlight the nature of the COVID-19 epidemic in MG and reinforce the need for real-time and continued genomic surveillance strategies to better understand and prepare for the epidemic spread of emerging viral pathogens..


Asunto(s)
Betacoronavirus/genética , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Genoma Viral , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , Adulto , Anciano , Brasil/epidemiología , COVID-19 , Femenino , Geografía , Humanos , Masculino , Persona de Mediana Edad , Pandemias , SARS-CoV-2 , Secuenciación Completa del Genoma , Adulto Joven
10.
J Wildl Dis ; 56(3): 693-697, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32216679

RESUMEN

Tick-borne protozoans of the genus Hepatozoon are obligate hemoparasites that can infect domestic and wild terrestrial vertebrates. Main hepatozoonosis affects canids and involves mainly Hepatozoon canis and Hepatozoon americanum. However, molecular studies revealed the capacity of H. canis to infect a wide range of wild mammals. In July 2018, we conducted an epidemiological survey for tick-borne pathogens in wild hosts, assaying Hepatozoon sp. occurrence in 34 bats captured in different habitats within a conservation unit in the state of Espírito Santo, southeastern Brazil. Blood and spleen tissue DNA samples were submitted to PCR amplifications of Babesia/Theileria and Hepatozoon 18S rRNA gene and 21% (7/34) were positive for Hepatozoon sp. Phylogenetic inferences grouped the obtained sequences from Seba's short-tailed bat (Carollia perspicillata) with the H. canis cluster, and from the great fruit-eating bat (Artibeus lituratus) with rodent-associated Hepatozoon cluster. Further studies are needed to characterize the epidemiological role of Seba's short-tailed bat and the great fruit-eating bat in the wild transmission cycle of these hemoparasites in Brazil.


Asunto(s)
Apicomplexa/genética , Quirópteros/parasitología , Infecciones Protozoarias en Animales/parasitología , Enfermedades por Picaduras de Garrapatas/veterinaria , Animales , Apicomplexa/aislamiento & purificación , Brasil/epidemiología , Filogenia , Infecciones Protozoarias en Animales/epidemiología , Bosque Lluvioso , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/parasitología
11.
Zoologia (Curitiba, Impr.) ; 37: e54982, Feb. 7, 2020. map, ilus, tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1504603

RESUMEN

Leptopanchax opalescens (Myers, 1942) is a small seasonal killifish endemic to coastal drainages in the state of Rio de Janeiro, Brazil. Leptopanchax opalescens was recaptured in temporary open vegetation pools (22°42.35S, 43°41.59W) in the hydrographic basin of the Guandu River, state of Rio de Janeiro, Brazil, after eight years without records. Information on habitat and population parameters (Capture per unit area (CPUA), size, sex ratio and length-weight relationship (LWR)) are given to provide subsidies for the conservation of this species. Specimens were captured during the rainy season (January-April 2020) in shallow pools (mean depth = 21 ± 12 s.d. cm), with relatively acidic pH (5.2 ± 0.8) and low concentrations of dissolved oxygen (3.5 ± 1 mg/L). The estimated CPUA of the population was 0.89 fish/m2. The total length (TL) of males ranged from 21.1 to 28.8 cm, and females ranged from 17.0 to 31.2 mm. Males were significantly larger (t-test = 2.04, p 0.05) than females, which were in greater proportion (2.83Female: 1Male, p 0.001). A positive allometric coefficient (b = 3.19) was found through length-weight relationship curve, indicating that individuals of the species gain proportionally more increment in weight than in length. Leptopanchax opalescens is a critically endangered species, and the results of this study contribute to the knowledge of the distribution, population structure and conservation of the species and its natural habitats.


Asunto(s)
Animales , Biodiversidad , Especies en Peligro de Extinción , Peces
12.
Zoologia (Curitiba) ; 37: e54982, 2020. mapas, ilus, tab, graf
Artículo en Inglés | VETINDEX | ID: vti-30544

RESUMEN

Leptopanchax opalescens (Myers, 1942) is a small seasonal killifish endemic to coastal drainages in the state of Rio de Janeiro, Brazil. Leptopanchax opalescens was recaptured in temporary open vegetation pools (22°42.35S, 43°41.59W) in the hydrographic basin of the Guandu River, state of Rio de Janeiro, Brazil, after eight years without records. Information on habitat and population parameters (Capture per unit area (CPUA), size, sex ratio and length-weight relationship (LWR)) are given to provide subsidies for the conservation of this species. Specimens were captured during the rainy season (January-April 2020) in shallow pools (mean depth = 21 ± 12 s.d. cm), with relatively acidic pH (5.2 ± 0.8) and low concentrations of dissolved oxygen (3.5 ± 1 mg/L). The estimated CPUA of the population was 0.89 fish/m2. The total length (TL) of males ranged from 21.1 to 28.8 cm, and females ranged from 17.0 to 31.2 mm. Males were significantly larger (t-test = 2.04, p 0.05) than females, which were in greater proportion (2.83Female: 1Male, p 0.001). A positive allometric coefficient (b = 3.19) was found through length-weight relationship curve, indicating that individuals of the species gain proportionally more increment in weight than in length. Leptopanchax opalescens is a critically endangered species, and the results of this study contribute to the knowledge of the distribution, population structure and conservation of the species and its natural habitats.(AU)


Asunto(s)
Animales , Especies en Peligro de Extinción , Peces , Biodiversidad
13.
J Virol ; 94(1)2019 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-31597773

RESUMEN

The recent reemergence of yellow fever virus (YFV) in Brazil has raised serious concerns due to the rapid dissemination of the virus in the southeastern region. To better understand YFV genetic diversity and dynamics during the recent outbreak in southeastern Brazil, we generated 18 complete and nearly complete genomes from the peak of the epidemic curve from nonhuman primates (NHPs) and human infected cases across the Espírito Santo and Rio de Janeiro states. Genomic sequencing of 18 YFV genomes revealed the estimated timing, source, and likely routes of yellow fever virus transmission and dispersion during one of the largest outbreaks ever registered in Brazil. We showed that during the recent epidemic, YFV was reintroduced from Minas Gerais to the Espírito Santo and Rio de Janeiro states multiple times between 2016 and 2019. The analysis of data from portable sequencing could identify the corridor of spread of YFV. These findings reinforce the idea that continued genomic surveillance strategies can provide information on virus genetic diversity and transmission dynamics that might assist in understanding arbovirus epidemics.IMPORTANCE Arbovirus infections in Brazil, including yellow fever, dengue, zika, and chikungunya, result in considerable morbidity and mortality and are pressing public health concerns. However, our understanding of these outbreaks is hampered by the limited availability of genomic data. In this study, we investigated the genetic diversity and spatial distribution of YFV during the current outbreak by analyzing genomic data from areas in southeastern Brazil not covered by other previous studies. To gain insights into the routes of YFV introduction and dispersion, we tracked the virus by sequencing YFV genomes sampled from nonhuman primates and infected patients from the southeastern region. Our study provides an understanding of how YFV initiates transmission in new Brazilian regions and illustrates that genomics in the field can augment traditional approaches to infectious disease surveillance and control.


Asunto(s)
Brotes de Enfermedades , Genoma Viral , Fiebre Amarilla/epidemiología , Fiebre Amarilla/transmisión , Virus de la Fiebre Amarilla/genética , Aedes/virología , Alouatta/virología , Animales , Brasil/epidemiología , Callithrix/virología , Cebus/virología , Femenino , Variación Genética , Humanos , Incidencia , Leontopithecus/virología , Masculino , Mosquitos Vectores/virología , Filogenia , Filogeografía , Secuenciación Completa del Genoma , Fiebre Amarilla/virología , Virus de la Fiebre Amarilla/clasificación , Virus de la Fiebre Amarilla/aislamiento & purificación , Virus de la Fiebre Amarilla/patogenicidad
14.
Bol. Inst. Pesca (Impr.) ; 45(2): e426, 2019. map, ilus, graf, tab
Artículo en Inglés | VETINDEX | ID: biblio-1465404

RESUMEN

The Brazilian codling Urophycis mystacea (Phycidae-Gadiformes) is a demersal-benthic species, present at the outer shelf and slope of Southeastern Brazil. Its stock has been declining since 2001, when it became a target species for the bottom trawling fleet, which went fishing between the outer shelf and the upper slope. In this study, we present results on the annual periodicity and deposition time of otolith rings, age, growth parameters and, relationships between otolith morphometric variables and age. Males were 1 to 6 years old, and females were 1 to 12 years old. The maximum likelihood ratio test proved that von Bertalanffy growth equations obtained for males and females were significantly different; respectively, Ct =419.33[1-exp-0.35(t-(-0.55))] and Ct=629.89[1-exp-0.17(t-(-0.89))]. The Potential Model presented the best fit for the relationship between the otolith morphometric variables and the fish age and its robustness, verified by the coefficient of determination values (R2). The otolith weight, followed by length, was the most adequate variables to estimate age.


A Abrótea-de-profundidade, Urophycis mystacea, é uma espécie demersal-bentônica, presente na plataforma externa e no talude da Região Sudeste-Sul do Brasil. Seu estoque vem diminuindo desde 2001, quando se tornou alvo da frota de arrasto de fundo, que passou a operar entre a plataforma externa e o talude superior. No presente estudo, investigamos o crescimento da espécie apresentando resultados sobre: periodicidade anual e época de formação dos anéis nos otólitos, idade e parâmetros de crescimento, além de relações entre variáveis morfométricas dos otólitos e idade. Foram encontrados machos com 1 a 6 anos e fêmeas com 1 a 12 anos de idade. A equação de crescimento de von Bertalanffy obtida para machos foi Ct = 419,33[1-exp-0,35(t-(-0,55))] e, para fêmeas, Ct = 629,89[1-exp-0,17(t-(-0,89))]. O teste da razão de máxima verossimilhança revelou diferenças significativas no crescimento entre sexos. A relação entre variáveis morfométricas dos otólitos e idade foi melhor representada pelo Modelo Potencial, e sua robustez, verificada através do valor do coeficiente de determinação (R2). O peso do otólito, seguido do comprimento, foram as mais adequadas para predizer a idade dos exemplares.


Asunto(s)
Animales , Gadiformes/crecimiento & desarrollo , Membrana Otolítica , Pesos y Medidas Corporales , Fauna Béntica
15.
B. Inst. Pesca ; 45(2): e426, 2019. mapas, ilus, graf, tab
Artículo en Inglés | VETINDEX | ID: vti-23683

RESUMEN

The Brazilian codling Urophycis mystacea (Phycidae-Gadiformes) is a demersal-benthic species, present at the outer shelf and slope of Southeastern Brazil. Its stock has been declining since 2001, when it became a target species for the bottom trawling fleet, which went fishing between the outer shelf and the upper slope. In this study, we present results on the annual periodicity and deposition time of otolith rings, age, growth parameters and, relationships between otolith morphometric variables and age. Males were 1 to 6 years old, and females were 1 to 12 years old. The maximum likelihood ratio test proved that von Bertalanffy growth equations obtained for males and females were significantly different; respectively, Ct =419.33[1-exp-0.35(t-(-0.55))] and Ct=629.89[1-exp-0.17(t-(-0.89))]. The Potential Model presented the best fit for the relationship between the otolith morphometric variables and the fish age and its robustness, verified by the coefficient of determination values (R2). The otolith weight, followed by length, was the most adequate variables to estimate age.(AU)


A Abrótea-de-profundidade, Urophycis mystacea, é uma espécie demersal-bentônica, presente na plataforma externa e no talude da Região Sudeste-Sul do Brasil. Seu estoque vem diminuindo desde 2001, quando se tornou alvo da frota de arrasto de fundo, que passou a operar entre a plataforma externa e o talude superior. No presente estudo, investigamos o crescimento da espécie apresentando resultados sobre: periodicidade anual e época de formação dos anéis nos otólitos, idade e parâmetros de crescimento, além de relações entre variáveis morfométricas dos otólitos e idade. Foram encontrados machos com 1 a 6 anos e fêmeas com 1 a 12 anos de idade. A equação de crescimento de von Bertalanffy obtida para machos foi Ct = 419,33[1-exp-0,35(t-(-0,55))] e, para fêmeas, Ct = 629,89[1-exp-0,17(t-(-0,89))]. O teste da razão de máxima verossimilhança revelou diferenças significativas no crescimento entre sexos. A relação entre variáveis morfométricas dos otólitos e idade foi melhor representada pelo Modelo Potencial, e sua robustez, verificada através do valor do coeficiente de determinação (R2). O peso do otólito, seguido do comprimento, foram as mais adequadas para predizer a idade dos exemplares.(AU)


Asunto(s)
Animales , Gadiformes/crecimiento & desarrollo , Membrana Otolítica , Pesos y Medidas Corporales , Fauna Béntica
16.
Zootaxa ; 4442(1): 137-152, 2018 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-30313987

RESUMEN

Two new species of Hemimycale from Southeastern Brazil are described in this study with the use of morphological and molecular data. Hemimycale oxeata sp. nov. is orange salmon colored in life and has unique oxeote like tornote spicules in addition to the typical (subtylo-)strongyles of the genus. Hemimycale ceadensis sp. nov. is reddish orange in life and has raised, tiny pore sieves, and subtylostrongyles with asymmetrical ends and raphides as microscleres. The diagnosis of the genus Hemimycale was slightly modified for the inclusion of the new species. Maximum-Likelihood analyses of 18S rRNA and COI sequences resulted in the clustering of both new species with the type species of the genus, thus confirming our morphological identification. The value of anatomical characters of pore sieves for diagnosing species and the genus is discussed. A key for species identification is also furnished.


Asunto(s)
Poríferos , Animales , Brasil , ARN Ribosómico 18S
17.
Transfus Apher Sci ; 57(1): 71-75, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29330014

RESUMEN

BACKGROUND AND OBJECTIVES: The frequency of red blood cell (RBC) antigens in Brazil varies due to differences in the ethnic groups in different regions; however, these studies have not been performed in Minas Gerais, where African admixture is more prevalent in comparison with other states. Due to these facts, this study aimed to determine the frequency of RBC genotypes on Rh, Kell, Duffy and Kidd systems in blood donors and multi-transfused patients from Minas Gerais, Southeast Brazil. METHODS: Blood samples were collected from 170 donors and 117 patients with different diagnosis and at least three RBC transfusions. DNA was extracted from leukocytes and genotyped by PCR-SSP, Multiplex or RFLP to alleles of the referred systems. The results were compared by the Chi-Square test, with a significance level of 5%. RESULTS: The most frequent genotypes were: RHD+, RHCE*ce/RHCE*ce, KEL*2/KEL*2, FY*B-67T/FY*B-67T and JK*A/JK*B. FY*B-67C/FY*B-67C, RHD*Ψ and JK*A/JK*A genotypes were more prevalent in sickle cell disease (SCD) patients than in donors. Many differences in RBC genotype frequencies were observed in comparison with studies from other states and countries. CONCLUSION: The results reinforce the importance of determining RBC genotypes of blood donors and patients in different regions of Brazil and the world, improving the transfusion safety of individuals requiring chronic RBC transfusions, especially those with SCD, due to ethnic differences in relation to donors.


Asunto(s)
Donantes de Sangre , Antígenos de Grupos Sanguíneos/genética , Transfusión de Eritrocitos , Eritrocitos , Genotipo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
Ticks Tick Borne Dis ; 9(1): 67-71, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29050834

RESUMEN

Brazilian spotted fever (BSF) is a potentially lethal human disease caused by Rickettsia rickettsii transmitted by ticks, including Amblyomma sculptum. However, in Southeast Brazil, where most BSF cases occur, capybaras are key hosts for both A. sculptum and Amblyomma dubitatum. We therefore compared the risk of human exposure to these ticks at a non-endemic anthropogenic site in Southeast Brazil where both tick species are maintained by capybaras and occur at high abundance. Cloth dragging, human baits and CO2 traps were used to assess tick abundance and risk for human exposure. The two tick species displayed profound differences in behavior and microhabitat use. Notably, A. sculptum but not A. dubitatum quested for hosts openly from vegetation (ambush behavior) and infested human baits. Furthermore, A. dubitatum was more aggregated at a specific site whereas A. sculptum was more widespread along differing and drier microhabitats. Adults and nymphs of both species were infected with Rickettsia bellii. Overall, the results indicate that even though both species co-existed in the same area, A. sculptum posed a greater risk for biting humans and thus also for transmitting tick-borne pathogens.


Asunto(s)
Distribución Animal , Conducta Animal , Ecosistema , Interacciones Huésped-Parásitos , Ixodidae/fisiología , Rickettsia , Fiebre Maculosa de las Montañas Rocosas/epidemiología , Animales , Brasil/epidemiología , Humanos , Ixodidae/crecimiento & desarrollo , Ixodidae/microbiología , Ninfa/crecimiento & desarrollo , Ninfa/microbiología , Ninfa/fisiología , Prevalencia , Medición de Riesgo , Fiebre Maculosa de las Montañas Rocosas/microbiología , Fiebre Maculosa de las Montañas Rocosas/parasitología , Roedores/fisiología , Especificidad de la Especie
19.
Environ Pollut ; 221: 116-129, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27914858

RESUMEN

We evaluated concentrations of eight heavy metals Cr, Zn, Pb, Ni, Cu, Cd, Co and V, in tissues of representative macrofauna species from 68 sandy beaches from the coast of Rio de Janeiro state. The links between contamination levels and community descriptors such as diversity, evenness, density and biomass, were also investigated. Metal concentrations from macrofaunal tissues were compared to maximum permissible limits for human ingestion stipulated by the Brazilian regulatory agency (ANVISA). Generalized linear models (GLM's) were used to investigate the variability in macrofauna density, richness, eveness and biomass in the seven different regions. A non-metric multidimensional scaling analysis (n-MDS) was used to investigate the spatial pattern of heavy metal concentrations along the seven regions of Rio de Janeiro coast. Variation partitioning was applied to evaluate the variance in the community assemblage explained by the environmental variables and the heavy metal concentrations. Our data suggested high spatial variation in the concentration of heavy metals in macrofauna species from the beaches of Rio de Janeiro. This result highlighted a diffuse source of contamination along the coast. Most of the metals concentrations were under the limits established by ANVISA. The variability in community descriptors was related to morphodynamic variables, but not with metal contamination values, indicating the lack of direct relationships at the community level. Concentration levels of eight heavy metals in macrofauna species from 68 sandy beaches on Rio de Janeiro coast (Brazil) were spatially correlated with anthropogenic activities such as industrialization and urbanization.


Asunto(s)
Monitoreo del Ambiente , Invertebrados/metabolismo , Metales Pesados/análisis , Contaminantes Químicos del Agua/metabolismo , Animales , Playas , Brasil , Ecosistema , Monitoreo del Ambiente/métodos , Metales Pesados/metabolismo , Urbanización , Contaminantes Químicos del Agua/análisis
20.
Mar Pollut Bull ; 115(1-2): 412-420, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28017366

RESUMEN

We examined the relationship between pollution and structure of copepod assemblages in estuaries, using sampling standardization of salinity range to reduce the effects of "Estuarine Quality Paradox". Copepod assemblages were analyzed in four Southeast Brazilian estuaries with different water quality levels and different hydrodynamic characteristics. The pollution negatively impacted the descriptors of the assemblage structure. The distribution of structure of copepod assemblages also showed a main separation trend between the most polluted estuaries and those less polluted. Temperature was the main factor affecting the assemblage structuring in the four estuaries. This factor acted in synergism with the effects of pollution impact and physical characteristics of the estuaries on the structure of copepod assemblages, supporting the potential vulnerability of coastal environments due to nutrient enrichment associated with climate change. Our study demonstrated the importance of sampling standardization of the salinity range in estuaries for reliable analysis of pollution effects on biota.


Asunto(s)
Copépodos , Estuarios , Animales , Brasil , Cambio Climático , Monitoreo del Ambiente , Hidrodinámica , Salinidad , Temperatura , Contaminación del Agua
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