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1.
Artigo em Português | VETINDEX | ID: biblio-1418956

Resumo

A mpox (varíola dos macacos ou monkeypox) é uma zoonose causada por um orthopoxvírus, da espécie Monkeypox virus (MPXV). Historicamente, primatas não humanos (PNHs) e, principalmente, roedores selvagens participam da manutenção do ciclo de transmissão em regiões endêmicas da África. Na atual epidemia de mpox em países não endêmicos, incluindo o Brasil, o ciclo epidemiológico apresenta transmissão direta de MPXV entre seres humanos, sem a participação de PNHs. O objetivo da revisão é apresentar informações históricas e o estado-da-arte da mpox com o intuito de orientar e fornecer subsídios sobre a doença aos médicos-veterinários, outros profissionais de saúde e a população em geral, além de desmitificar a participação dos PNHs, uma vez que estes não participam do ciclo de transmissão da doença em países não endêmicos.(AU)


Mpox (monkeypox) is a zoonotic disease caused by an orthopoxvirus, species Monkeypox virus (MPXV). Historically, non-human primates (NHPs) and wild rodents participate in maintaining the transmission cycle in endemic regions of Africa. In the current epidemic of human mpox in non-endemic countries, including Brazil, the epidemiological cycle of human mpox shows direct transmission of the MPXV between humans, without the participation of NHPs. The objective of this review is to present historical information and the state-of-the-art of human mpox to guide and provide subsidies about the disease to veterinarians, other health professionals and the population in general, in addition to demystifying the participation of PNHs in the HM transmission cycle in non-endemic countries.(AU)


Assuntos
Monkeypox virus/patogenicidade , Mpox/transmissão , Mpox/epidemiologia
2.
Braz. j. biol ; 83: 1-8, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468927

Resumo

The present study was designed to evaluate the strength of association of raised plasma homocysteine concentration as a risk factor for coronary heart disease independent of conventional risk factor. It was a case control study conducted at Punjab Institute of Cardiology Lahore. A total of 210 subjects aged 25 to 60 years comprising of 105 newly admitted patients of CHD as cases and 105 age and sex matched healthy individuals with no history of CHD as control were recruited for the study. Fasting blood samples were obtained from cases and controls. Plasma homocysteine was analyzed by fluorescence polarization immunoassay (FPIA) method on automated immunoassay analyzer (Abbott IMX). Total cholesterol, triglyceride and HDL cholesterol were analyzed using calorimetric kit methods. The concentration of LDL cholesterol was calculated using Friedewald formula. The patients were also assessed for traditional risk factors such as age, sex, family history of CVD, hypertension, smoking and physical activity, and were compared with control subjects. The collected data was entered in SPSS version 24 for analysis and interpretation.The mean age in controls and experimental groups were 43.00± 8.42 years and 44.72± 8.59 years with statistically same distribution (p- value= 0.144). The mean plasma homocysteine for cases was 22.33± 9.22 µmol/L where as it was 12.59±3.73 µmol/L in control group. Highly significant difference was seen between the mean plasma level of homocysteine in cases and controls (p˂0.001).Simple logistic regression indicates a strong association of coronary heart disease with hyperhomocysteinemia (OR 7.45), which remained significantly associated with coronary heart disease by multivariate logistic regression (OR 7.10, 95%C1 3.12-12.83, p=0.000). The present study concludes that elevated levels of Plasma homocysteine is an independent risk factor [...].


O presente estudo foi desenhado para avaliar a força da associação da concentração elevada de homocisteína no plasma como um fator de risco para doença cardíaca coronária independente do fator de risco convencional. Foi um estudo de caso-controle realizado no Punjab Institute of Cardiology Lahore. Um total de 210 indivíduos com idade entre 25 e 60 anos, compreendendo 105 pacientes recém-admitidos de CHD como casos e 105 indivíduos saudáveis pareados por idade e sexo sem histórico de CHD como controle, foi recrutado para o estudo. Amostras de sangue em jejum foram obtidas de casos e controles. A homocisteína plasmática foi analisada pelo método de imunoensaio de polarização de fluorescência (FPIA) em analisador de imunoensaio automatizado (Abbott IMX). Colesterol total, triglicerídeos e colesterol HDL foram analisados usando métodos de kit calorimétrico. A concentração de colesterol LDL foi calculada pela fórmula de Friedewald. Os pacientes também foram avaliados para fatores de risco tradicionais, como idade, sexo, história familiar de DCV, hipertensão, tabagismo e atividade física, e foram comparados com indivíduos de controle. Os dados coletados foram inseridos no SPSS versão 24 para análise e interpretação. A média de idade nos grupos controles e experimentais foi de 43,00 ± 8,42 anos e 44,72 ± 8,59 anos com distribuição estatisticamente igual (p-valor = 0,144). A homocisteína plasmática média para os casos foi de 22,33 ± 9,22 µmol / L, enquanto no grupo controle foi de 12,59 ± 3,73 µmol / L. Diferença altamente significativa foi observada entre o nível plasmático médio de homocisteína em casos e controles (p ˂ 0,001). A regressão logística simples indica uma forte associação de doença cardíaca coronária com hiper-homocisteinemia (OR 7,45), que permaneceu significativamente associada com doença cardíaca coronária por multivariada regressão logística (OR 7,10, 95% C1 3,12-12,83, p = 0,000). O presente estudo conclui [...].


Assuntos
Humanos , Adulto Jovem , Adulto , Doença das Coronárias/prevenção & controle , Doença das Coronárias/sangue , Homocisteína/análise
3.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469143

Resumo

Abstract The present study was designed to evaluate the strength of association of raised plasma homocysteine concentration as a risk factor for coronary heart disease independent of conventional risk factor. It was a case control study conducted at Punjab Institute of Cardiology Lahore. A total of 210 subjects aged 25 to 60 years comprising of 105 newly admitted patients of CHD as cases and 105 age and sex matched healthy individuals with no history of CHD as control were recruited for the study. Fasting blood samples were obtained from cases and controls. Plasma homocysteine was analyzed by fluorescence polarization immunoassay (FPIA) method on automated immunoassay analyzer (Abbott IMX). Total cholesterol, triglyceride and HDL cholesterol were analyzed using calorimetric kit methods. The concentration of LDL cholesterol was calculated using Friedewald formula. The patients were also assessed for traditional risk factors such as age, sex, family history of CVD, hypertension, smoking and physical activity, and were compared with control subjects. The collected data was entered in SPSS version 24 for analysis and interpretation.The mean age in controls and experimental groups were 43.00± 8.42 years and 44.72± 8.59 years with statistically same distribution (p- value= 0.144). The mean plasma homocysteine for cases was 22.33± 9.22 µmol/L where as it was 12.59±3.73 µmol/L in control group. Highly significant difference was seen between the mean plasma level of homocysteine in cases and controls (p0.001).Simple logistic regression indicates a strong association of coronary heart disease with hyperhomocysteinemia (OR 7.45), which remained significantly associated with coronary heart disease by multivariate logistic regression (OR 7.10, 95%C1 3.12-12.83, p=0.000). The present study concludes that elevated levels of Plasma homocysteine is an independent risk factor for coronary heart disease independent of conventional risk factors and can be used as an indicator for predicting the future possibility for the onset of CVD.


Resumo O presente estudo foi desenhado para avaliar a força da associação da concentração elevada de homocisteína no plasma como um fator de risco para doença cardíaca coronária independente do fator de risco convencional. Foi um estudo de caso-controle realizado no Punjab Institute of Cardiology Lahore. Um total de 210 indivíduos com idade entre 25 e 60 anos, compreendendo 105 pacientes recém-admitidos de CHD como casos e 105 indivíduos saudáveis pareados por idade e sexo sem histórico de CHD como controle, foi recrutado para o estudo. Amostras de sangue em jejum foram obtidas de casos e controles. A homocisteína plasmática foi analisada pelo método de imunoensaio de polarização de fluorescência (FPIA) em analisador de imunoensaio automatizado (Abbott IMX). Colesterol total, triglicerídeos e colesterol HDL foram analisados usando métodos de kit calorimétrico. A concentração de colesterol LDL foi calculada pela fórmula de Friedewald. Os pacientes também foram avaliados para fatores de risco tradicionais, como idade, sexo, história familiar de DCV, hipertensão, tabagismo e atividade física, e foram comparados com indivíduos de controle. Os dados coletados foram inseridos no SPSS versão 24 para análise e interpretação. A média de idade nos grupos controles e experimentais foi de 43,00 ± 8,42 anos e 44,72 ± 8,59 anos com distribuição estatisticamente igual (p-valor = 0,144). A homocisteína plasmática média para os casos foi de 22,33 ± 9,22 µmol / L, enquanto no grupo controle foi de 12,59 ± 3,73 µmol / L. Diferença altamente significativa foi observada entre o nível plasmático médio de homocisteína em casos e controles (p 0,001). A regressão logística simples indica uma forte associação de doença cardíaca coronária com hiper-homocisteinemia (OR 7,45), que permaneceu significativamente associada com doença cardíaca coronária por multivariada regressão logística (OR 7,10, 95% C1 3,12-12,83, p = 0,000). O presente estudo conclui que níveis elevados de homocisteína plasmática são fator de risco independente para doença cardíaca coronária, independentemente dos fatores de risco convencionais, e pode ser usado como um indicador para prever a possibilidade futura de aparecimento de DCV.

4.
Braz. j. biol ; 83: e249104, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339389

Resumo

Abstract The present study was designed to evaluate the strength of association of raised plasma homocysteine concentration as a risk factor for coronary heart disease independent of conventional risk factor. It was a case control study conducted at Punjab Institute of Cardiology Lahore. A total of 210 subjects aged 25 to 60 years comprising of 105 newly admitted patients of CHD as cases and 105 age and sex matched healthy individuals with no history of CHD as control were recruited for the study. Fasting blood samples were obtained from cases and controls. Plasma homocysteine was analyzed by fluorescence polarization immunoassay (FPIA) method on automated immunoassay analyzer (Abbott IMX). Total cholesterol, triglyceride and HDL cholesterol were analyzed using calorimetric kit methods. The concentration of LDL cholesterol was calculated using Friedewald formula. The patients were also assessed for traditional risk factors such as age, sex, family history of CVD, hypertension, smoking and physical activity, and were compared with control subjects. The collected data was entered in SPSS version 24 for analysis and interpretation.The mean age in controls and experimental groups were 43.00± 8.42 years and 44.72± 8.59 years with statistically same distribution (p- value= 0.144). The mean plasma homocysteine for cases was 22.33± 9.22 µmol/L where as it was 12.59±3.73 µmol/L in control group. Highly significant difference was seen between the mean plasma level of homocysteine in cases and controls (p˂0.001).Simple logistic regression indicates a strong association of coronary heart disease with hyperhomocysteinemia (OR 7.45), which remained significantly associated with coronary heart disease by multivariate logistic regression (OR 7.10, 95%C1 3.12-12.83, p=0.000). The present study concludes that elevated levels of Plasma homocysteine is an independent risk factor for coronary heart disease independent of conventional risk factors and can be used as an indicator for predicting the future possibility for the onset of CVD.


Resumo O presente estudo foi desenhado para avaliar a força da associação da concentração elevada de homocisteína no plasma como um fator de risco para doença cardíaca coronária independente do fator de risco convencional. Foi um estudo de caso-controle realizado no Punjab Institute of Cardiology Lahore. Um total de 210 indivíduos com idade entre 25 e 60 anos, compreendendo 105 pacientes recém-admitidos de CHD como casos e 105 indivíduos saudáveis ​​pareados por idade e sexo sem histórico de CHD como controle, foi recrutado para o estudo. Amostras de sangue em jejum foram obtidas de casos e controles. A homocisteína plasmática foi analisada pelo método de imunoensaio de polarização de fluorescência (FPIA) em analisador de imunoensaio automatizado (Abbott IMX). Colesterol total, triglicerídeos e colesterol HDL foram analisados ​​usando métodos de kit calorimétrico. A concentração de colesterol LDL foi calculada pela fórmula de Friedewald. Os pacientes também foram avaliados para fatores de risco tradicionais, como idade, sexo, história familiar de DCV, hipertensão, tabagismo e atividade física, e foram comparados com indivíduos de controle. Os dados coletados foram inseridos no SPSS versão 24 para análise e interpretação. A média de idade nos grupos controles e experimentais foi de 43,00 ± 8,42 anos e 44,72 ± 8,59 anos com distribuição estatisticamente igual (p-valor = 0,144). A homocisteína plasmática média para os casos foi de 22,33 ± 9,22 µmol / L, enquanto no grupo controle foi de 12,59 ± 3,73 µmol / L. Diferença altamente significativa foi observada entre o nível plasmático médio de homocisteína em casos e controles (p ˂ 0,001). A regressão logística simples indica uma forte associação de doença cardíaca coronária com hiper-homocisteinemia (OR 7,45), que permaneceu significativamente associada com doença cardíaca coronária por multivariada regressão logística (OR 7,10, 95% C1 3,12-12,83, p = 0,000). O presente estudo conclui que níveis elevados de homocisteína plasmática são fator de risco independente para doença cardíaca coronária, independentemente dos fatores de risco convencionais, e pode ser usado como um indicador para prever a possibilidade futura de aparecimento de DCV.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Doença das Coronárias/embriologia , Hiper-Homocisteinemia/diagnóstico , Hiper-Homocisteinemia/epidemiologia , Estudos de Casos e Controles , Fatores de Risco , Jejum
5.
Neotrop. ichthyol ; 21(1): e220103, 2023. mapas, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1418883

Resumo

Data obtained by direct observation of organisms in their natural habitats can provide valuable contributions regarding intra- and inter-specific interactions, as well as spatial distribution and trophic relationships. However, relatively few such data are available for the Neotropical ichthyofauna relative to the great species diversity of this region. We present data on the ichthyofauna in karst environments of the Serra da Bodoquena, Upper Paraguay River basin regarding their categorization into functional trophic groups. We used direct observations that focused on the most frequent feeding tactics and their spatial (vertical and horizontal) distribution in the channel. We observed 83 fish species in 17 functional trophic groups. The greatest species richness was concentrated in the Characidae and Loricariidae in the categories Diurnal Backwater Drift Feeders and Grazers, respectively. Regarding horizontal depth stratification, we found a positive relationship between the association of small fish with the shallow marginal habitats. This work represents a contribution to a region known for its high tourist potential and to the important diversity of the entire ichthyofauna of the Upper Paraguay basin region that requires proper conservation strategies for sustaining these species.(AU)


Dados obtidos pela observação direta dos organismos em seus hábitats naturais podem fornecer valiosas contribuições com relação a interações intra e inter-específicas, além de distribuição espacial e relações tróficas. Entretanto, relativamente poucos dados estão disponíveis no que diz respeito à ictiofauna neotropical dada à grande diversidade dessa região. Apresentamos dados sobre a ictiofauna em ambientes cársticos da Serra da Bodoquena, bacia do alto rio Paraguai e a categorização das mesmas em grupos tróficos funcionais baseada em observações diretas relacionadas às táticas alimentares mais frequentes e à sua distribuição espacial (vertical e horizontal) no canal. Assim sendo, observamos 83 espécies de peixes alocadas em 17 grupos tróficos funcionais. A maior riqueza de espécies concentrou-se nas famílias Characidae e Loricariidae, abrangendo as categorias Catadores Diurnos de Itens Arrastados pela Corrente e Pastadores, respectivamente. Com relação à estratificação horizontal, encontramos a relação positiva entre a associação de peixes de pequeno porte com relação aos hábitats marginais. Esse trabalho representa uma contribuição a uma região conhecida pelo seu alto potencial turístico e à importante diversidade da ictiofauna da região da bacia do alto Paraguai que requer estratégias de conservação adequadas para sustentar essas espécies.(AU)


Assuntos
Animais , Cadeia Alimentar , Comportamento Alimentar , Peixes/fisiologia , Brasil , Ecossistema , Níveis Tróficos
6.
Braz. J. Biol. ; 83: 1-8, 2023. tab
Artigo em Inglês | VETINDEX | ID: vti-765504

Resumo

The present study was designed to evaluate the strength of association of raised plasma homocysteine concentration as a risk factor for coronary heart disease independent of conventional risk factor. It was a case control study conducted at Punjab Institute of Cardiology Lahore. A total of 210 subjects aged 25 to 60 years comprising of 105 newly admitted patients of CHD as cases and 105 age and sex matched healthy individuals with no history of CHD as control were recruited for the study. Fasting blood samples were obtained from cases and controls. Plasma homocysteine was analyzed by fluorescence polarization immunoassay (FPIA) method on automated immunoassay analyzer (Abbott IMX). Total cholesterol, triglyceride and HDL cholesterol were analyzed using calorimetric kit methods. The concentration of LDL cholesterol was calculated using Friedewald formula. The patients were also assessed for traditional risk factors such as age, sex, family history of CVD, hypertension, smoking and physical activity, and were compared with control subjects. The collected data was entered in SPSS version 24 for analysis and interpretation.The mean age in controls and experimental groups were 43.00± 8.42 years and 44.72± 8.59 years with statistically same distribution (p- value= 0.144). The mean plasma homocysteine for cases was 22.33± 9.22 µmol/L where as it was 12.59±3.73 µmol/L in control group. Highly significant difference was seen between the mean plasma level of homocysteine in cases and controls (p˂0.001).Simple logistic regression indicates a strong association of coronary heart disease with hyperhomocysteinemia (OR 7.45), which remained significantly associated with coronary heart disease by multivariate logistic regression (OR 7.10, 95%C1 3.12-12.83, p=0.000). The present study concludes that elevated levels of Plasma homocysteine is an independent risk factor [...].(AU)


O presente estudo foi desenhado para avaliar a força da associação da concentração elevada de homocisteína no plasma como um fator de risco para doença cardíaca coronária independente do fator de risco convencional. Foi um estudo de caso-controle realizado no Punjab Institute of Cardiology Lahore. Um total de 210 indivíduos com idade entre 25 e 60 anos, compreendendo 105 pacientes recém-admitidos de CHD como casos e 105 indivíduos saudáveis pareados por idade e sexo sem histórico de CHD como controle, foi recrutado para o estudo. Amostras de sangue em jejum foram obtidas de casos e controles. A homocisteína plasmática foi analisada pelo método de imunoensaio de polarização de fluorescência (FPIA) em analisador de imunoensaio automatizado (Abbott IMX). Colesterol total, triglicerídeos e colesterol HDL foram analisados usando métodos de kit calorimétrico. A concentração de colesterol LDL foi calculada pela fórmula de Friedewald. Os pacientes também foram avaliados para fatores de risco tradicionais, como idade, sexo, história familiar de DCV, hipertensão, tabagismo e atividade física, e foram comparados com indivíduos de controle. Os dados coletados foram inseridos no SPSS versão 24 para análise e interpretação. A média de idade nos grupos controles e experimentais foi de 43,00 ± 8,42 anos e 44,72 ± 8,59 anos com distribuição estatisticamente igual (p-valor = 0,144). A homocisteína plasmática média para os casos foi de 22,33 ± 9,22 µmol / L, enquanto no grupo controle foi de 12,59 ± 3,73 µmol / L. Diferença altamente significativa foi observada entre o nível plasmático médio de homocisteína em casos e controles (p ˂ 0,001). A regressão logística simples indica uma forte associação de doença cardíaca coronária com hiper-homocisteinemia (OR 7,45), que permaneceu significativamente associada com doença cardíaca coronária por multivariada regressão logística (OR 7,10, 95% C1 3,12-12,83, p = 0,000). O presente estudo conclui [...].(AU)


Assuntos
Humanos , Adulto Jovem , Adulto , Doença das Coronárias/sangue , Doença das Coronárias/prevenção & controle , Homocisteína/análise
7.
Iheringia, Sér. zool ; 112: e2022019, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1405118

Resumo

The effect of climatic conditions on the structure of populations has been perceived for different orders of insects and families of beetles. Here we described the population dynamics of Euspilotus azureus (Sahlberg, 1823) and determined its relationship with climatic variables. The specimens were collected monthly for one year in an area of Seasonal Semideciduous Forest, in Viçosa, Brazil. The seasonality of the population and of sexes was estimated through the absolute frequency of occurrence (AF) and the percentage frequency of occurrence (FO%) of the population and each sex, which were determined monthly. To test whether the changes in monthly AF of the population and of each sex are correlated with climatic variables, Spearman correlation tests were performed. To identify whether there are temporal fluctuations in the sex ratio, considering months and seasons, and within each season, we performed Chi-square tests. A total of 3,126 individuals (1,009 females and 2,117 males) were collected. The population had the highest abundance in spring and summer, and the lowest in autumn and winter. The highest AF and FO were found in December and January, and the lowest in June and July. The sex ratio of the population did not differ in the months of the year, but in the spring there was a marked predominance of males. For E. azureus, the temporal fluctuation in abundance of the population and in the sex ratio is related to the climatic variables of maximum temperature, humidity, and precipitation. Climatic variables, especially the temperature, provided a greater abundance of the population in the hottest and rainiest periods of the year for inducing reproductive activity and altering the population's sex ratio.


O efeito das condições climáticas na estrutura das populações tem sido percebido para diferentes ordens de insetos e famílias de besouros. Nós descrevemos a dinâmica populacional temporal de Euspilotus azureus (Sahlberg, 1823) e determinamos sua relação com as variáveis climáticas. Os espécimes foram coletados durante um ano em uma área de Floresta Semidecidual Sazonal, em Viçosa, Brasil. A sazonalidade da população e dos sexos foi estimada através da frequência de ocorrência absoluta (FA) e da frequência de ocorrência percentual (FO%) da população, as quais foram determinadas mensalmente. Para testar se as mudanças mensais na FA da população e de cada sexo estão correlacionadas com as variáveis climáticas, testes de correlação de Spearman foram realizados. Para identificar se há oscilações temporais na razão sexual considerando meses e estações, e dentro de cada estação, foram realizados testes de Qui-quadrado. Um total de 3.126 indivíduos (1.009 fêmeas e 2.117 machos) foram coletados. A população teve maior abundância na primavera e verão, e menor no outono e inverno. As maiores FA e FO foram em dezembro e janeiro, e a menores em junho e julho. A razão sexual da população não diferiu nos meses do ano, mas na primavera houve uma predominância marcante de machos. Para E. azureus, a flutuação temporal na abundância da população e na razão sexual é explicada pelas variáveis climáticas de temperatura máxima, umidade e precipitação. As variáveis climáticas, especialmente a temperatura, propiciaram uma maior abundância da população nos períodos os mais quentes e chuvosos do ano por induzirem a atividade reprodutiva e a alterar da razão sexual da população.


Assuntos
Animais , Besouros , Estações do Ano , Razão de Masculinidade , Brasil , Dinâmica Populacional
8.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487438

Resumo

Abstract New World bats are involved in key ecological processes and are good indicators of environmental changes. Recently, trait-based approaches have been used in several taxa to better understand mechanisms underlying species assemblages, biotic interactions, environmental relationships and ecosystem functions. However, despite the relevance of bats on ecosystem dynamics, so far, there is no conceptual framework that relies on the measurement of bat traits to address functional studies. Here, we present a set of 50 bat biological traits, which are suitable to assess environmental stressors and can potentially affect ecological processes. Several examples were provided to show the applicability of this framework in the study of Neotropical bat ecology. We suggest some considerations regarding trait-based approach including the importance of intraspecific variation, correlations between traits, response-effect framework, global dataset, and future directions to assess the reliability of functional relations across species and Neotropical regions by using traits. This could be helpful in tackling ecological questions associated with community assembly and habitat filtering, species diversity patterns along environmental gradients, and ecological processes. We envision this paper as a first step toward an integrative bat functional trait protocol held up with solid evidence.

9.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487484

Resumo

Abstract The high mountain environment is a tough habitat that imposes many challenges to reptiles. As temperature decreases with altitude and has a dramatic variation throughout the day in the tropical mountains, ectotherms must cope with these harsh conditions. We studied the use of microhabitat and activity patterns of Stenocercus trachycephalus in the eastern Andes mountain range of Colombia. Three localities were sampled across the wide altitudinal distribution of this lizard species, in a range from 2,670 to 3,950 m a.s.l. The initial hypothesis was that these natural history traits would change with altitude but instead, we found that they remained roughly consistent, showing the great plasticity of this species. The results support that this lizard is a microhabitat-generalist using principally herb across the gradient, rarely shifting to specific plants or microhabitats such as rocks depending on availability. Regarding the activity pattern, this species was active throughout the day from 8:00 to 16:00 with a similar pattern along the gradient. Nevertheless, some differences were detected across localities. The activity pattern shifted from bimodal in the lower locality to unimodal in the higher ones. As expected, a correlation between temperature and activity patterns was found in one of the study sites. However, this was not the case for the lower and mid-elevation localities, where there was no correlation between these variables. The mid-elevation study site was the most interesting locality as the use of microhabitat relied virtually just on the herb stratum and the activity was constrained to the morning hours. These findings may be the result of the synergic effects of other ecological variables (weather variability, human impact, predation, population structure, or reproductive season). Our study gives the basis for a better understanding of how behavior (microhabitat choice and hours of activity) of ectotherms can help to counter thermal constraints in the neotropics when facing an altitudinal gradient. Further studies should focus on the thermal biology of this species, considering the influence of anthropic impact on these lizards populations.

10.
Pap. avulsos zool ; 61: e20216124, 2021. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1287459

Resumo

Abstract New World bats are involved in key ecological processes and are good indicators of environmental changes. Recently, trait-based approaches have been used in several taxa to better understand mechanisms underlying species assemblages, biotic interactions, environmental relationships and ecosystem functions. However, despite the relevance of bats on ecosystem dynamics, so far, there is no conceptual framework that relies on the measurement of bat traits to address functional studies. Here, we present a set of 50 bat biological traits, which are suitable to assess environmental stressors and can potentially affect ecological processes. Several examples were provided to show the applicability of this framework in the study of Neotropical bat ecology. We suggest some considerations regarding trait-based approach including the importance of intraspecific variation, correlations between traits, response-effect framework, global dataset, and future directions to assess the reliability of functional relations across species and Neotropical regions by using traits. This could be helpful in tackling ecological questions associated with community assembly and habitat filtering, species diversity patterns along environmental gradients, and ecological processes. We envision this paper as a first step toward an integrative bat functional trait protocol held up with solid evidence.

11.
Pap. avulsos zool ; 61: e20216170, 2021. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1340294

Resumo

Abstract The high mountain environment is a tough habitat that imposes many challenges to reptiles. As temperature decreases with altitude and has a dramatic variation throughout the day in the tropical mountains, ectotherms must cope with these harsh conditions. We studied the use of microhabitat and activity patterns of Stenocercus trachycephalus in the eastern Andes mountain range of Colombia. Three localities were sampled across the wide altitudinal distribution of this lizard species, in a range from 2,670 to 3,950 m a.s.l. The initial hypothesis was that these natural history traits would change with altitude but instead, we found that they remained roughly consistent, showing the great plasticity of this species. The results support that this lizard is a microhabitat-generalist using principally herb across the gradient, rarely shifting to specific plants or microhabitats such as rocks depending on availability. Regarding the activity pattern, this species was active throughout the day from 8:00 to 16:00 with a similar pattern along the gradient. Nevertheless, some differences were detected across localities. The activity pattern shifted from bimodal in the lower locality to unimodal in the higher ones. As expected, a correlation between temperature and activity patterns was found in one of the study sites. However, this was not the case for the lower and mid-elevation localities, where there was no correlation between these variables. The mid-elevation study site was the most interesting locality as the use of microhabitat relied virtually just on the herb stratum and the activity was constrained to the morning hours. These findings may be the result of the synergic effects of other ecological variables (weather variability, human impact, predation, population structure, or reproductive season). Our study gives the basis for a better understanding of how behavior (microhabitat choice and hours of activity) of ectotherms can help to counter thermal constraints in the neotropics when facing an altitudinal gradient. Further studies should focus on the thermal biology of this species, considering the influence of anthropic impact on these lizards' populations.

12.
Pap. avulsos Zool. ; 61: e20216124, 2021. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-765689

Resumo

New World bats are involved in key ecological processes and are good indicators of environmental changes. Recently, trait-based approaches have been used in several taxa to better understand mechanisms underlying species assemblages, biotic interactions, environmental relationships and ecosystem functions. However, despite the relevance of bats on ecosystem dynamics, so far, there is no conceptual framework that relies on the measurement of bat traits to address functional studies. Here, we present a set of 50 bat biological traits, which are suitable to assess environmental stressors and can potentially affect ecological processes. Several examples were provided to show the applicability of this framework in the study of Neotropical bat ecology. We suggest some considerations regarding trait-based approach including the importance of intraspecific variation, correlations between traits, response-effect framework, global dataset, and future directions to assess the reliability of functional relations across species and Neotropical regions by using traits. This could be helpful in tackling ecological questions associated with community assembly and habitat filtering, species diversity patterns along environmental gradients, and ecological processes. We envision this paper as a first step toward an integrative bat functional trait protocol held up with solid evidence.(AU)


Assuntos
Animais , Quirópteros/crescimento & desenvolvimento , Ecossistema , Características de História de Vida , Biomarcadores Ambientais
13.
Pap. avulsos Zool. ; 61: e20216170, 2021. mapas, ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-33279

Resumo

The high mountain environment is a tough habitat that imposes many challenges to reptiles. As temperature decreases with altitude and has a dramatic variation throughout the day in the tropical mountains, ectotherms must cope with these harsh conditions. We studied the use of microhabitat and activity patterns of Stenocercus trachycephalus in the eastern Andes mountain range of Colombia. Three localities were sampled across the wide altitudinal distribution of this lizard species, in a range from 2,670 to 3,950 m a.s.l. The initial hypothesis was that these natural history traits would change with altitude but instead, we found that they remained roughly consistent, showing the great plasticity of this species. The results support that this lizard is a microhabitat-generalist using principally herb across the gradient, rarely shifting to specific plants or microhabitats such as rocks depending on availability. Regarding the activity pattern, this species was active throughout the day from 8:00 to 16:00 with a similar pattern along the gradient. Nevertheless, some differences were detected across localities. The activity pattern shifted from bimodal in the lower locality to unimodal in the higher ones. As expected, a correlation between temperature and activity patterns was found in one of the study sites. However, this was not the case for the lower and mid-elevation localities, where there was no correlation between these variables. The mid-elevation study site was the most interesting locality as the use of microhabitat relied virtually just on the herb stratum and the activity was constrained to the morning hours. These findings may be the result of the synergic effects of other ecological variables (weather variability, human impact, predation, population structure, or reproductive season). Our study gives the basis for a better understanding of how behavior (microhabitat choice and hours of activity) of ectotherms can help to counter thermal constraints in the neotropics when facing an altitudinal gradient. Further studies should focus on the thermal biology of this species, considering the influence of anthropic impact on these lizards populations.(AU)


Assuntos
Animais , Iguanas/anatomia & histologia , Iguanas/classificação , Ecossistema , Ecologia
14.
Neotrop. ichthyol ; 19(2): e200075, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1279476

Resumo

Electrophorus spp. generate high-voltage electric discharges for defense and hunting, and low-voltage electric discharges (as other Gymnotiformes) for electrolocation and communication. Despite intense interest in the unusual electrogenic and electroreceptive capacities of electric eels, the other sensory systems of Electrophorus spp. are relatively poorly known. Here we describe the ontogenetic development and organization of the cephalic lateral-line canals in the lowland electric eel, Electrophorus varii. Preserved specimens of larvae, juveniles, and adults were examined to describe the spatial distribution of the canals and pores. Ontogenetic shifts of the cephalic lateral line formation were observed for each canal and support a hypothesis of non-synchronized development. The morphogenesis of cephalic canals in larvae and juveniles begins just before the onset of exogenous feeding. In adults, the cephalic sensory canals are formed separately from the skull and overlay cranial and mandibular bones and muscles. This study provides the first detailed description of the development and organization of the cephalic lateral-line system in Electrophorus varii.(AU)


Electrophorus spp. geram descargas elétricas de alta voltagem, usadas para defesa e caça, e (como os demais Gymnotiformes) descargas elétricas de baixa voltagem para eletrolocalização e comunicação. Apesar do grande interesse nas capacidades eletrogênicas e eletrorreceptivas incomuns dos poraquês, os outros sistemas sensoriais de Electrophorus spp. são relativamente pouco conhecidos. Aqui nós descrevemos o desenvolvimento ontogenético e a organização dos canais da linha lateral cefálica no poraquê da planície Electrophorus varii. Exemplares preservados de larvas, juvenis e adultos foram analisados para descrever a distribuição espacial dos canais e poros. Variações ontogenéticas na formação da linha lateral cefálica foram observadas para cada canal, apresentando um desenvolvimento não-sincronizado. Variações ontogenéticas da formação da linha lateral cefálica foram observadas para cada canal e suportam uma hipótese de desenvolvimento assincrônico. A morfogênese dos canais cefálicos em larvas e juvenis precede o início da alimentação exógena. Nos adultos, os canais sensoriais cefálicos se formam separadamente do crânio e sobrepõem os ossos e músculos cranianos e mandibulares. Este estudo fornece a primeira descrição detalhada do desenvolvimento e organização do sistema da linha lateral cefálica de Electrophorus varii.(AU)


Assuntos
Animais , Gimnotiformes , Enguias , Sistema da Linha Lateral , Estágios do Ciclo de Vida , Características de Residência , Músculos
15.
Neotrop. ichthyol ; 19(2): e200075, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-31440

Resumo

Electrophorus spp. generate high-voltage electric discharges for defense and hunting, and low-voltage electric discharges (as other Gymnotiformes) for electrolocation and communication. Despite intense interest in the unusual electrogenic and electroreceptive capacities of electric eels, the other sensory systems of Electrophorus spp. are relatively poorly known. Here we describe the ontogenetic development and organization of the cephalic lateral-line canals in the lowland electric eel, Electrophorus varii. Preserved specimens of larvae, juveniles, and adults were examined to describe the spatial distribution of the canals and pores. Ontogenetic shifts of the cephalic lateral line formation were observed for each canal and support a hypothesis of non-synchronized development. The morphogenesis of cephalic canals in larvae and juveniles begins just before the onset of exogenous feeding. In adults, the cephalic sensory canals are formed separately from the skull and overlay cranial and mandibular bones and muscles. This study provides the first detailed description of the development and organization of the cephalic lateral-line system in Electrophorus varii.(AU)


Electrophorus spp. geram descargas elétricas de alta voltagem, usadas para defesa e caça, e (como os demais Gymnotiformes) descargas elétricas de baixa voltagem para eletrolocalização e comunicação. Apesar do grande interesse nas capacidades eletrogênicas e eletrorreceptivas incomuns dos poraquês, os outros sistemas sensoriais de Electrophorus spp. são relativamente pouco conhecidos. Aqui nós descrevemos o desenvolvimento ontogenético e a organização dos canais da linha lateral cefálica no poraquê da planície Electrophorus varii. Exemplares preservados de larvas, juvenis e adultos foram analisados para descrever a distribuição espacial dos canais e poros. Variações ontogenéticas na formação da linha lateral cefálica foram observadas para cada canal, apresentando um desenvolvimento não-sincronizado. Variações ontogenéticas da formação da linha lateral cefálica foram observadas para cada canal e suportam uma hipótese de desenvolvimento assincrônico. A morfogênese dos canais cefálicos em larvas e juvenis precede o início da alimentação exógena. Nos adultos, os canais sensoriais cefálicos se formam separadamente do crânio e sobrepõem os ossos e músculos cranianos e mandibulares. Este estudo fornece a primeira descrição detalhada do desenvolvimento e organização do sistema da linha lateral cefálica de Electrophorus varii.(AU)


Assuntos
Animais , Gimnotiformes , Enguias , Sistema da Linha Lateral , Estágios do Ciclo de Vida , Características de Residência , Músculos
16.
Bol. Inst. Pesca (Impr.) ; 47: e640, 2021. map, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1465491

Resumo

The length–weight relationship (LWR) is an important tool for ichthyology. It is very useful to demonstrate the environmental influence on growth. In this study we estimate the LWR of the Atherinella brasiliensis in the shallow areas of the São Francisco River estuary and compare the growth of this specie in different environments of the Brazilian coast. Specimens of Brazilian silverside (A. brasiliensis, n = 3483), between 2.1 and 13.6 cm in length, were caught in the shallow areas of the São Francisco River estuary between May 2017 and April 2018. The length-weight ratio of the species was represented by the equation y = 0.0047x3.0913. Frequency distribution indicates that the species is present in the studied area in all its ontogenetic stages and apparently reproduces throughout the year with constant input of recruits into the population. Von Bertalanffy’s growth model and longevity were adjusted to reach asymptotic length (L∞) of 14.7 cm, growth coefficient (K) of 0.91 year-1 and longevity (A95) of 3.25 years. The analysis of variance revealed differences for the maximum total length. However, the differences found between the present study and data available in the literature appear to be caused by environmental and methodological differences.


A relação peso-comprimento (LWR) é uma ferramenta importante para a ictiologia, muito utilizada para demonstrar a influência ambiental no crescimento. Neste estudo estimamos o LWR de Atherinella brasiliensis em áreas rasas do estuário do rio São Francisco e comparamos o crescimento desta espécie em diferentes ambientes do litoral brasileiro. Espécimes do peixe-rei (A. brasiliensis, n = 3483), entre 2,1 e 13,6 cm de comprimento, foram capturados nas áreas rasas do estuário do rio São Francisco entre maio de 2017 e abril de 2018. A relação peso-comprimento das espécies foi representada por a equação y = 0,0047x3,0913. A distribuição de frequência indica que a espécie está presente na área estudada em todos os seus estágios ontogenéticos e aparentemente se reproduz ao longo do ano com entrada constante de recrutas na população. Os modelos de crescimento e longevidade de Von Bertalanffy foram ajustados para atingir comprimento assintótico (L∞) de 14,7 cm, coeficiente de crescimento (K) de 0,91 ano-1 e longevidade (A95) de 3,25 anos. A análise de variância revelou diferenças para o comprimento total máximo. No entanto, as diferenças encontradas entre o presente estudo e os dados disponíveis na literatura parecem ser causadas por diferenças ambientais e metodológicas.


Assuntos
Animais , Peixes/crescimento & desenvolvimento , Peixes/genética
17.
Neotrop. ichthyol ; 19(4): e200105, 2021. graf, mapas, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1351159

Resumo

The semi-anadromous sea catfish species Cathorops tuyra (Ariidae, Besudo sea catfish) from the Tropical Eastern Pacific has been found reproductively active in the freshwater rivers and lakes of the Panama Canal. Despite growing concerns for biodiversity, reports on natural history are lacking for many Neotropical sea catfishes. We aimed to provide data on the diet and seasonal timing of spawning of C. tuyra for an autochthonous, semi-anadromous, brackish water population from Rio Santa Maria and an allochthonous freshwater non-migrating population from Rio Chagres, an affluent to the Panama Canal, to understand how changing from semi-anadromous to residential lifestyle affects the natural history of a species. Fish from both sampling sites were dissected and information on stomach content, size, weight, parasitic load, sex, maturity, and number of eggs were recorded. In Rio Chagres, there was a female bias and individuals were larger and in pre-spawning mode compared to Rio Santa Maria. Parasite prevalence was low in Rio Chagres and zero in Rio Santa Maria. The diets were very similar between populations: gastropods, bivalves, and insects were the most important prey items in both rivers representing a diverse omnivorous diet that is similar to that of other catfishes.(AU)


El bagre de mar semi-anádromo Cathorops tuyra (Ariidae, Bagre besudo) del Pacífico Oriental Tropical se encuentra reproductivamente activa en los ríos y lagos del Canal de Panamá. A pesar de la creciente preocupación por la biodiversidad, faltan informes sobre la historia natural de muchos de los bagres Neotropicales. Nuestro objetivo es proporcionar datos básicos sobre la dieta y el momento del desove estacional de C. tuyra para una población autóctona semi-anádroma de agua salobre de Río Santa María y una población alóctona residente de agua dulce de Río Chagres para comprender cómo el cambio de un estilo de vida semi-anádromo a residencial afecta la historia natural de una especie. Se disecaron peces de ambos sitios de muestreo y se registró la información de contenido del estómago, tamaño, peso, carga parasitaria, sexo, madurez y número de huevos. En Río Chagres hubo un sesgo femenino y los individuos eran más grandes y estaban en modo pre-desove que en Río Santa María. La prevalencia de parásitos fue baja en el Río Chagres y cero en Río Santa María. Las dietas fueron muy similares entre poblaciones: gasterópodos, bivalvos e insectos fueron las presas más importantes en ambos ríos, lo que representa una dieta omnívora diversa, que es similar a la de otros bagres.(AU)


Assuntos
Animais , Peixes-Gato/classificação , História Natural/educação , Biodiversidade , Barragens , Relatório de Pesquisa
18.
Neotrop. ichthyol ; 19(4): e200105, 2021. graf, mapas, ilus
Artigo em Inglês | VETINDEX | ID: vti-765888

Resumo

The semi-anadromous sea catfish species Cathorops tuyra (Ariidae, Besudo sea catfish) from the Tropical Eastern Pacific has been found reproductively active in the freshwater rivers and lakes of the Panama Canal. Despite growing concerns for biodiversity, reports on natural history are lacking for many Neotropical sea catfishes. We aimed to provide data on the diet and seasonal timing of spawning of C. tuyra for an autochthonous, semi-anadromous, brackish water population from Rio Santa Maria and an allochthonous freshwater non-migrating population from Rio Chagres, an affluent to the Panama Canal, to understand how changing from semi-anadromous to residential lifestyle affects the natural history of a species. Fish from both sampling sites were dissected and information on stomach content, size, weight, parasitic load, sex, maturity, and number of eggs were recorded. In Rio Chagres, there was a female bias and individuals were larger and in pre-spawning mode compared to Rio Santa Maria. Parasite prevalence was low in Rio Chagres and zero in Rio Santa Maria. The diets were very similar between populations: gastropods, bivalves, and insects were the most important prey items in both rivers representing a diverse omnivorous diet that is similar to that of other catfishes.(AU)


El bagre de mar semi-anádromo Cathorops tuyra (Ariidae, Bagre besudo) del Pacífico Oriental Tropical se encuentra reproductivamente activa en los ríos y lagos del Canal de Panamá. A pesar de la creciente preocupación por la biodiversidad, faltan informes sobre la historia natural de muchos de los bagres Neotropicales. Nuestro objetivo es proporcionar datos básicos sobre la dieta y el momento del desove estacional de C. tuyra para una población autóctona semi-anádroma de agua salobre de Río Santa María y una población alóctona residente de agua dulce de Río Chagres para comprender cómo el cambio de un estilo de vida semi-anádromo a residencial afecta la historia natural de una especie. Se disecaron peces de ambos sitios de muestreo y se registró la información de contenido del estómago, tamaño, peso, carga parasitaria, sexo, madurez y número de huevos. En Río Chagres hubo un sesgo femenino y los individuos eran más grandes y estaban en modo pre-desove que en Río Santa María. La prevalencia de parásitos fue baja en el Río Chagres y cero en Río Santa María. Las dietas fueron muy similares entre poblaciones: gasterópodos, bivalvos e insectos fueron las presas más importantes en ambos ríos, lo que representa una dieta omnívora diversa, que es similar a la de otros bagres.(AU)


Assuntos
Animais , Peixes-Gato/classificação , História Natural/educação , Biodiversidade , Barragens , Relatório de Pesquisa
19.
B. Inst. Pesca ; 47: 1-9, 2021. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-764688

Resumo

The length–weight relationship (LWR) is an important tool for ichthyology. It is very useful to demonstrate the environmental influence on growth. In this study we estimate the LWR of the Atherinella brasiliensis in the shallow areas of the São Francisco River estuary and compare the growth of this specie in different environments of the Brazilian coast. Specimens of Brazilian silverside (A. brasiliensis, n = 3483), between 2.1 and 13.6 cm in length, were caught in the shallow areas of the São Francisco River estuary between May 2017 and April 2018. The length-weight ratio of the species was represented by the equation y = 0.0047x3.0913. Frequency distribution indicates that the species is present in the studied area in all its ontogenetic stages and apparently reproduces throughout the year with constant input of recruits into the population. Von Bertalanffys growth model and longevity were adjusted to reach asymptotic length (L∞) of 14.7 cm, growth coefficient (K) of 0.91 year-1 and longevity (A95) of 3.25 years. The analysis of variance revealed differences for the maximum total length. However, the differences found between the present study and data available in the literature appear to be caused by environmental and methodological differences.(AU)


A relação peso-comprimento (LWR) é uma ferramenta importante para a ictiologia, muito utilizada para demonstrar a influência ambiental no crescimento. Neste estudo estimamos o LWR de Atherinella brasiliensis em áreas rasas do estuário do rio São Francisco e comparamos o crescimento desta espécie em diferentes ambientes do litoral brasileiro. Espécimes do peixe-rei (A. brasiliensis, n = 3483), entre 2,1 e 13,6 cm de comprimento, foram capturados nas áreas rasas do estuário do rio São Francisco entre maio de 2017 e abril de 2018. A relação peso-comprimento das espécies foi representada por a equação y = 0,0047x3,0913. A distribuição de frequência indica que a espécie está presente na área estudada em todos os seus estágios ontogenéticos e aparentemente se reproduz ao longo do ano com entrada constante de recrutas na população. Os modelos de crescimento e longevidade de Von Bertalanffy foram ajustados para atingir comprimento assintótico (L∞) de 14,7 cm, coeficiente de crescimento (K) de 0,91 ano-1 e longevidade (A95) de 3,25 anos. A análise de variância revelou diferenças para o comprimento total máximo. No entanto, as diferenças encontradas entre o presente estudo e os dados disponíveis na literatura parecem ser causadas por diferenças ambientais e metodológicas.(AU)


Assuntos
Animais , Peixes/crescimento & desenvolvimento , Peixes/genética
20.
Neotrop. ichthyol ; 19(4)2021.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1485615

Resumo

RESUMEN La estrategia reproductiva de una especie debe ajustarse a las variaciones de las condiciones ambientales para garantizar el equilibrio poblacional. En los riachos amazónicos de tierra firme las fluctuaciones hidrológicas están controladas principalmente por las lluvias locales, predominando especies de peces de pequeño porte. Investigamos la estrategia reproductiva de Helogenes marmoratus y la influencia de variables ambientales (e.g., lluvia, conductividad, descriptores del hábitat) en su actividad reproductiva. Colectamos mensualmente entre marzo de 2019 y marzo de 2020 en una microcuenca del río Guamá, en la Amazonia oriental brasileña. Identificamos un período reproductivo prolongado entre julio de 2019 y marzo de 2020. Los machos comienzan a reproducirse con un menor tamaño ( = 27.41; = 31.36 mm). Confirmamos desove parcial, baja fecundidad (59.55 ± 22.76 ovócitos) y ovócitos grandes (1.24 ± 0.15 mm). La estrategia reproductiva de H. marmoratus ocupa un lugar intermedio entre el gradiente oportunista y de equilibrio. Regresiones múltiples destacan la importancia de la profundidad, la conductividad eléctrica, los bancos de hojas y la lluvia como reguladores de la actividad reproductiva de las hembras, explicando 32% de la variación del IGS. Nuestro estudio proporciona evidencia de una respuesta reproductiva diferenciada entre los sexos a las variables ambientales.


ABSTRACT The reproductive strategy of a species must be adjusted to variations in environmental conditions to guarantee population balance. Hydrological fluctuations in Amazonian streams of terra firme (non-flooded) are controlled primarily by local rainfall. Fish assemblages are composed predominantly of species of small size. We investigated the reproductive strategy of the cryptic catfish Helogenes marmoratus and assessed the influence of environmental variables (e.g., rainfall, conductivity, habitat descriptors) on its reproductive activity in a catchment of the Guamá River in the eastern Brazilian Amazon. Through monthly collections between March 2019 and March 2020, we identified an extended reproductive period between July 2019 and March 2020. Males mature at smaller sizes than females ( = 27.41 mm; = 31.36 mm). We confirmed batch spawning, low fecundity (59.55 ± 22.76 stage IV oocytes), and large oocytes (1.24 ± 0.15 mm). Our results indicated that H. marmoratus strategy occupies an intermediate place between opportunistic and equilibrium gradient. Multiple regressions showed that thalweg depth, electrical conductivity, leaf litter, and rainfall are important drivers of reproductive activity of females of H. marmoratus, explaining 32% of the variation of the GSI. Our study provides evidence of differentiated reproductive response between the sexes to environmental variables.

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