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1.
Anim Reprod Sci ; 188: 1-12, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29233618

RESUMO

Changes in the nutritional plan have been shown to affect oocyte quality, crucial to oocyte donors animals used in cloning. This study aimed to evaluate the impact of diets with increasing nutritional levels (maintenance diet=M; 1.3M; 1.6M; 1.9M) fed to goats for four weeks on follicular fluid composition, gene expression and oocyte competence used to cloning in goats. Donor females were superovulated for the retrieval of matured oocytes and physical measurements reported. After four weeks, groups receiving diets above maintenance increased thickness of subcutaneous adipose tissue and body weight, with higher values in 1.9M Group (P<0.05). Treatments did not affect follicular density, number of aspirated follicles, retrieved and matured oocytes. Animals from 1.3M group had lower (P<0.05) maturation rate (44.0%) and number of viable oocytes (65.3%) than M (68.8%) and 1.9M (76.0%). Follicular fluid glucose concentrations increased with nutritional levels (P=0.010), with a difference (P<0.05) between groups 1.9M (11.4±2.6mg/dL) and M (2.6±0.5mg/dL). The diet did not affect the expression of GDF9, BMP15, and BAX genes in oocytes, but BCL2 and apoptotic index were significantly higher (P<0.05) in the 1.3M and 1.6M groups than the other groups. Following the transfer of cloned embryos, one fetus was born live of a twin pregnancy in the 1.9M Group. The association between energy intake and oocyte quality suggests better nutritional use by oocytes when the maximum flow was used (1.9M), but the optimal feeding level in cloning still needs refinement.


Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Desenvolvimento Embrionário/fisiologia , Cabras/embriologia , Animais , Clonagem de Organismos , Transferência Embrionária/veterinária , Ingestão de Energia , Feminino , Fertilização in vitro/veterinária , Líquido Folicular/química , Regulação da Expressão Gênica/fisiologia , Cabras/metabolismo , Técnicas de Maturação in Vitro de Oócitos/veterinária , Técnicas de Transferência Nuclear/veterinária , Recuperação de Oócitos , Gravidez , Superovulação
2.
Braz. j. biol ; Braz. j. biol;77(1): 162-169, Jan-Mar. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839156

RESUMO

Abstract Predatory mites that belong to the Phytoseiidae family are one of the main natural enemies of phytophagous mites, thus allowing for their use as a biological control. Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae) is among the main species of predatory mites used for this purpose. Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) is considered to be one of the most important species of mite pests and has been described as attacking over 1,100 species of plants in 140 families with economic value. The objective of the present study was to investigate, in the laboratory, the reproductive parameters of the predatory mite P. macropilis when fed T. urticae. Experiments were conducted under laboratory conditions at 25 ± 2 °C of temperature, 70 ± 10% RH and 14 hours of photophase. In addition, biological aspects were evaluated and a fertility life table was established. The results of these experiments demonstrated that the longevity of adult female was 27.5 days and adult male was 29.0 days. The population was estimated to increase approximately 27 times (Ro) in mean generation time (T), which was 17.7 days. Lastly, the mite population grew 1.2 times/day (λ) and doubled every 3.7 days (TD).


Resumo Os ácaros predadores pertencentes à família Phytoseiidae constituem um dos principais inimigos naturais de ácaros fitófagos, o que possibilita o seu uso em controle biológico. Entre as principais espécies destaca-se Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae). O ácaro Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) é considerado uma das espécies de ácaros-praga mais importantes, atacando mais de 1.100 espécies de plantas em 140 famílias de valor econômico. Este trabalho foi realizado com o objetivo de estudar, em laboratório, os parâmetros reprodutivos do ácaro predador P. macropilis, quando alimentado com T. urticae. Os estudos foram conduzidos em laboratório à temperatura de 25 ± 2 °C, 70 ± 10% de UR e 14 horas de fotofase e foram avaliados os aspectos biológicos e confeccionada a tabela de vida de fertilidade. Foi constatada uma longevidade de 27,5 dias para fêmeas adultas e 29,0 dias para machos. A população foi estimada em aumentar aproximadamente 27 vezes (Ro) no período médio de duração de geração (T) que foi de 17,7 dias. A população do ácaro cresceu 1,2vezes/dia (λ) e dobrou a cada 3,7 dias (TD).


Assuntos
Animais , Masculino , Feminino , Reprodução , Tetranychidae , Longevidade , Ácaros/fisiologia
3.
Braz. J. Biol. ; 77(1): 162-169, jan.-mar. 2017. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-734878

RESUMO

Predatory mites that belong to the Phytoseiidae family are one of the main natural enemies of phytophagous mites, thus allowing for their use as a biological control. Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae) is among the main species of predatory mites used for this purpose. Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) is considered to be one of the most important species of mite pests and has been described as attacking over 1,100 species of plants in 140 families with economic value. The objective of the present study was to investigate, in the laboratory, the reproductive parameters of the predatory mite P. macropilis when fed T. urticae.Experiments were conducted under laboratory conditions at 25 ± 2 °C of temperature, 70 ± 10% RH and 14 hours of photophase. In addition, biological aspects were evaluated and a fertility life table was established. The results of these experiments demonstrated that the longevity of adult female was 27.5 days and adult male was 29.0 days. The population was estimated to increase approximately 27 times (Ro) in mean generation time (T), which was 17.7 days. Lastly, the mite population grew 1.2 times/day (λ) and doubled every 3.7 days (TD).(AU)


Os ácaros predadores pertencentes à família Phytoseiidae constituem um dos principais inimigos naturais de ácaros fitófagos, o que possibilita o seu uso em controle biológico. Entre as principais espécies destaca-se Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae). O ácaro Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) é considerado uma das espécies de ácaros-praga mais importantes, atacando mais de 1.100 espécies de plantas em 140 famílias de valor econômico. Este trabalho foi realizado com o objetivo de estudar, em laboratório, os parâmetros reprodutivos do ácaro predador P. macropilis, quando alimentado com T. urticae. Os estudos foram conduzidos em laboratório à temperatura de 25 ± 2 °C, 70 ± 10% de UR e 14 horas de fotofase e foram avaliados os aspectos biológicos e confeccionada a tabela de vida de fertilidade. Foi constatada uma longevidade de 27,5 dias para fêmeas adultas e 29,0 dias para machos. A população foi estimada em aumentar aproximadamente 27 vezes (Ro) no período médio de duração de geração (T) que foi de 17,7 dias. A população do ácaro cresceu 1,2vezes/dia (λ) e dobrou a cada 3,7 dias (TD).(AU)


Assuntos
Ácaros/embriologia , Ácaros/crescimento & desenvolvimento , Controle Biológico de Vetores , Estágios do Ciclo de Vida , Tábuas de Vida , Comportamento Predatório , Fertilidade
4.
Braz J Biol ; 0: 0, 2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27409230

RESUMO

Predatory mites that belong to the Phytoseiidae family are one of the main natural enemies of phytophagous mites, thus allowing for their use as a biological control. Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae) is among the main species of predatory mites used for this purpose. Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) is considered to be one of the most important species of mite pests and has been described as attacking over 1,100 species of plants in 140 families with economic value. The objective of the present study was to investigate, in the laboratory, the reproductive parameters of the predatory mite P. macropilis when fed T. urticae. Experiments were conducted under laboratory conditions at 25 ± 2 °C of temperature, 70 ± 10% RH and 14 hours of photophase. In addition, biological aspects were evaluated and a fertility life table was established. The results of these experiments demonstrated that the longevity of adult female was 27.5 days and adult male was 29.0 days. The population was estimated to increase approximately 27 times (Ro) in mean generation time (T), which was 17.7 days. Lastly, the mite population grew 1.2 times/day (λ) and doubled every 3.7 days (TD).


Assuntos
Longevidade , Ácaros/fisiologia , Reprodução , Tetranychidae , Animais , Feminino , Masculino
5.
Anim. Reprod. ; 12(2): 291-297, Apr.-June.2015. graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-745443

RESUMO

Lipotoxicity is characterized by excessive saturated fatty acids in the blood, increasing storage in non-adipose cells, which leads to changes in the expression pattern of genes related to endoplasmic reticulum stress (e.g., ATF4, ATF6, CHOP, And GRP78), pro- and anti-apoptotic pathways (e.g., Baxand Bcl-2, and protein stability, including heat shock proteins, e.g., HSP70). A negative sub-cellular effect is usually an end result, which also occurs in the ovarian follicular population, affecting granulosa cells and cumulus-oocyte complexes (COCs), which leads to adecrease in oocyte quality and mitochondrial activity, and increased apoptosis. The addition of high doses of non-esterified fatty acids to oocyte in vitro maturation medium has been shown to slow the progression of meio sis, hampering oocyte maturation and subsequent in vitro embryo development. Due to its importance in the control of cellular lipid droplets and expression correlation with cytosolic lipid accumulation, the expression of the Plin 2 (Perilipin 2) Protein is also highlighted. The aim of this Review is to discuss some reproductive implications of dietary li pid supplementation in ruminant females, and the potential effects of lipotoxicityon oocyte qualityand reproduction, and the main mechanisms involved in the expression of genes related to endoplasmic reticulum stress and cellular lipid accumulation.(AU)


Assuntos
Animais , Feminino , Mamíferos/embriologia , Ácidos Graxos/sangue , Ácidos Graxos/toxicidade , Embrião de Mamíferos , Técnicas Reprodutivas/veterinária
6.
Anim. Reprod. (Online) ; 12(2): 291-297, Apr.-June.2015. graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1461151

RESUMO

Lipotoxicity is characterized by excessive saturated fatty acids in the blood, increasing storage in non-adipose cells, which leads to changes in the expression pattern of genes related to endoplasmic reticulum stress (e.g., ATF4, ATF6, CHOP, And GRP78), pro- and anti-apoptotic pathways (e.g., Baxand Bcl-2, and protein stability, including heat shock proteins, e.g., HSP70). A negative sub-cellular effect is usually an end result, which also occurs in the ovarian follicular population, affecting granulosa cells and cumulus-oocyte complexes (COCs), which leads to adecrease in oocyte quality and mitochondrial activity, and increased apoptosis. The addition of high doses of non-esterified fatty acids to oocyte in vitro maturation medium has been shown to slow the progression of meio sis, hampering oocyte maturation and subsequent in vitro embryo development. Due to its importance in the control of cellular lipid droplets and expression correlation with cytosolic lipid accumulation, the expression of the Plin 2 (Perilipin 2) Protein is also highlighted. The aim of this Review is to discuss some reproductive implications of dietary li pid supplementation in ruminant females, and the potential effects of lipotoxicityon oocyte qualityand reproduction, and the main mechanisms involved in the expression of genes related to endoplasmic reticulum stress and cellular lipid accumulation.


Assuntos
Feminino , Animais , Embrião de Mamíferos , Mamíferos/embriologia , Ácidos Graxos/sangue , Ácidos Graxos/toxicidade , Técnicas Reprodutivas/veterinária
7.
Arq. bras. med. vet. zootec ; 66(2): 563-572, jan.-abr. 2014. graf, tab
Artigo em Português | VETINDEX | ID: vti-10751

RESUMO

O presente estudo foi conduzido para determinar o consumo e a digestibilidade dos nutrientes, bem como o comportamento ingestivo de cordeiros Somalis Brasileira, alimentados com diferentes níveis de energia metabolizável (EM). Foram utilizados 40 animais, não castrados, com peso vivo médio de 13,47±1,76kg. Os animais foram distribuídos em delineamento em blocos ao acaso, com cinco dietas com diferentes níveis de energia metabolizável (1,18; 2,07; 2,25; 2,42 e 2,69Mcal/kg de MS). O consumo de MS, PB, FDN, CF (g/dia), MS (g/kg0,75) e FDN (%PC e g/kg0,75) apresentaram efeito quadrático (P<0,05), assim como os coeficientes de digestibilidade (P<0,05) da PB, da FDN e dos CF. Foi averiguado efeito linear crescente (P<0,05) para digestibilidade da MS, da MO e dos CNF com o aumento da EM na dieta. Os tempos de alimentação e ócio (h/dia) foram influenciados pelos níveis de energia (P<0,05), e as eficiências de alimentação e ruminação (g FDN/h) apresentaram efeito quadrático (P<0,05). Conclui-se que o aumento dos níveis de EM das rações influencia o consumo e a digestibilidade dos nutrientes, bem como o comportamento ingestivo de cordeiros Somalis Brasileira.(AU)


The study was conducted to determine the intake, nutrient digestibility and ingestive behavior of Brazilian Somali lambs fed different levels of metabolizable energy (ME). Forty non-castrated Brazilian Somali lambs with average weight of 13.47±1.76kg were used. The animals were assigned to a randomized block design with eight replications per block and five diets with increasing metabolizable energy (1.18, 2.07, 2.25, 2.42 and 2.69 Mcal/kg DM). The quadratic effect (P<0.05) of the ME level was determined for DM, CP, NDF and FC (g/day) and DM (g/kg0,75) and NDF(%PC and g/kg0,75) intake, as well as the digestibility coefficients (P<0.05) for CP, NDF and CF. A linear effect (P<0.05) was observed for digestibility of DM, OM and NFC with the increase of ME in the diet. Eating and idle results (hours/day) were influenced by the energy levels (P<0.05) and efficiencies of feeding and rumination (g NDF/h) showed a quadratic effect (P<0.05). It is concluded that the increase of ME levels in the diet influences intatke, nutrient digestibility and ingestive behavior of Brazilian Somali lambs.(AU)


Assuntos
Animais , Ovinos/metabolismo , Ração Animal , Ingestão de Alimentos , Fenômenos Fisiológicos da Nutrição Animal , Metabolismo Energético/fisiologia , Nutrientes , Digestão/fisiologia , Absorção , Fatores de Tempo
8.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);66(2): 563-572, Jan.-Apr. 2014. graf, tab
Artigo em Português | LILACS | ID: lil-709298

RESUMO

O presente estudo foi conduzido para determinar o consumo e a digestibilidade dos nutrientes, bem como o comportamento ingestivo de cordeiros Somalis Brasileira, alimentados com diferentes níveis de energia metabolizável (EM). Foram utilizados 40 animais, não castrados, com peso vivo médio de 13,47±1,76kg. Os animais foram distribuídos em delineamento em blocos ao acaso, com cinco dietas com diferentes níveis de energia metabolizável (1,18; 2,07; 2,25; 2,42 e 2,69Mcal/kg de MS). O consumo de MS, PB, FDN, CF (g/dia), MS (g/kg0,75) e FDN (%PC e g/kg0,75) apresentaram efeito quadrático (P<0,05), assim como os coeficientes de digestibilidade (P<0,05) da PB, da FDN e dos CF. Foi averiguado efeito linear crescente (P<0,05) para digestibilidade da MS, da MO e dos CNF com o aumento da EM na dieta. Os tempos de alimentação e ócio (h/dia) foram influenciados pelos níveis de energia (P<0,05), e as eficiências de alimentação e ruminação (g FDN/h) apresentaram efeito quadrático (P<0,05). Conclui-se que o aumento dos níveis de EM das rações influencia o consumo e a digestibilidade dos nutrientes, bem como o comportamento ingestivo de cordeiros Somalis Brasileira...


The study was conducted to determine the intake, nutrient digestibility and ingestive behavior of Brazilian Somali lambs fed different levels of metabolizable energy (ME). Forty non-castrated Brazilian Somali lambs with average weight of 13.47±1.76kg were used. The animals were assigned to a randomized block design with eight replications per block and five diets with increasing metabolizable energy (1.18, 2.07, 2.25, 2.42 and 2.69 Mcal/kg DM). The quadratic effect (P<0.05) of the ME level was determined for DM, CP, NDF and FC (g/day) and DM (g/kg0,75) and NDF(%PC and g/kg0,75) intake, as well as the digestibility coefficients (P<0.05) for CP, NDF and CF. A linear effect (P<0.05) was observed for digestibility of DM, OM and NFC with the increase of ME in the diet. Eating and idle results (hours/day) were influenced by the energy levels (P<0.05) and efficiencies of feeding and rumination (g NDF/h) showed a quadratic effect (P<0.05). It is concluded that the increase of ME levels in the diet influences intatke, nutrient digestibility and ingestive behavior of Brazilian Somali lambs...


Assuntos
Animais , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Ingestão de Alimentos , Metabolismo Energético/fisiologia , Nutrientes , Ovinos/metabolismo , Absorção , Digestão/fisiologia , Fatores de Tempo
9.
Environ Monit Assess ; 185(7): 6173-85, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23224644

RESUMO

The three-stage sequential extraction procedure for the fractionation of Cd, Cr, Cu, Ni, Pb, and Zn, proposed by the Commission of the European Communities Bureau of Reference, was applied to sediment five samples collected from the Sal estuary, Sergipe State, northeast Brazil, in September 2009. The method showed satisfactory recoveries, detection limits, and standard deviations for determinations of trace metals in the sediments. Cd and Pb were the metals most prevalent in the bioavailable fractions (carbonates, Fe and Mn oxides, organic matter, and sulfides), while Ni, Zn, Cu, and Cr showed higher percentages in the inert fraction. The order of mobility of the metals was Cd (66%) > Pb (65%) > Zn (59%) > Ni (57%) = Cr (57%) > Cu (56%). Possible toxicity related to these metals was examined using the risk assessment code, and by comparing the chemical data with sediment quality guideline ERL-ERM values. Results obtained using the two methods were in agreement, and showed low to medium risk for all metals, indicating that adverse effects on aquatic biota should rarely occur.


Assuntos
Estuários , Sedimentos Geológicos/química , Metais/análise , Modelos Químicos , Poluentes Químicos da Água/análise , Brasil , Monitoramento Ambiental , Medição de Risco
10.
Plant Biol (Stuttg) ; 13(4): 602-10, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21668601

RESUMO

Pollen transport to a receptive stigma can be facilitated through different pollinators, which submits the pollen to different selection pressures. This study aimed to associate pollen and stigma morphology with zoophily in species of the tribe Phaseoleae. Species of the genera Erythrina, Macroptilium and Mucuna with different pollinators were chosen. Pollen grains and stigmas were examined under light microscopy (anatomy), scanning electronic microscopy (surface analyses) and transmission electronic microscopy (ultrastructure). The three genera differ in terms of pollen wall ornamentation, pollen size, pollen aperture, thickness of the pollen wall, amount of pollenkitt, pollen hydration status and dominant reserves within the pollen grain, while species within each genus are very similar in most studied characteristics. Most of these features lack relationships to pollinator type, especially in Erythrina and Mucuna. Pollen reserves are discussed on a broad scale, according to the occurrence of protein in the pollen of invertebrate- or vertebrate-pollinated species. Some pollen characteristics are more associated to semi-dry stigma requirements. This apical, compact, cuticularised and secretory stigma occurs in all species investigated. We conclude that data on pollen and stigma structure should be included together with those on floral morphology and pollinator behaviour for the establishment of functional pollination classes.


Assuntos
Fabaceae/anatomia & histologia , Flores/anatomia & histologia , Pólen/ultraestrutura , Polinização , Animais , Fabaceae/química , Fabaceae/classificação , Flores/química , Proteínas de Plantas/análise , Pólen/química , Reprodução , Especificidade da Espécie
11.
J Chromatogr Sci ; 47(9): 822-4, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19835697

RESUMO

Agricultural development and its associated impacts on the environment are resulting in increasingly restrictive guidelines and legislation concerning the use of chemicals in agro-ecosystems. The herbicide glyphosate is widely used for weed control in both cultivated and uncultivated areas and is considered to show low toxicity to mammals. It is highly water-soluble, and its monitoring in surface, underground, and potable waters is recommended by the United States Environmental Protection Agency. This work presents a method for the inclusion of glyphosate determination within routine anion analysis using ion chromatography in water sampler without any kind of extraction, clean-up, or preconcentration step. The equipment used was a Dionex Model ICS-3000 ion chromatograph fitted with a 25-microL loop, Ion Pac AG19 guard and AS19 analytical columns, ASRS-300 (2 mm) suppressor, and conductivity detector. The method showed a linear response to glyphosate between 0.05-0.75 mg/L with a correlation coefficient of 0.999, and a detection limit below the maximum levels permitted by Brazilian legislation. Recoveries in the range 90-105% were achieved in tests using surface, well, potable, and ultrapure water samples.

12.
J Hazard Mater ; 163(2-3): 517-23, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18722053

RESUMO

The physicochemical characteristics of three Brazilian peats were investigated using elemental analysis, scanning electron microscopy (SEM), X-ray diffractometry (XRD) and studies of Cr(III) biosorption based on adsorption isotherms. Adsorption of Cr(III) by in natura peat from Santo Amaro das Brotas (Sergipe State) was much greater than by peats from either Ribeirão Preto (São Paulo State) or Itabaiana (Sergipe State), with adsorption capacities (q) of 4.90+/-0.01, 1.70+/-0.01 and 1.40+/-0.01 mg g(-1), respectively. Pre-treatments with HCl and NaOH+HCl reduced adsorption by the Santo Amaro das Brotas peat, showing that adsorption efficiency was associated with the amount of organic matter present. Conversely, increase in the mineral content following pre-treatment increased adsorption of Cr(III) by the Ribeirão Preto and Itabaiana peats. Highest adsorption (retention >95.0%) was achieved at equilibrium pH 4.0 using the Santo Amaro das Brotas peat. Experimental data for the adsorption of Cr(III) from aqueous solution onto this peat were fitted to the Langmuir equation, from which an equilibrium adsorption capacity, q(max), of 5.60 mg g(-1) was obtained, which was close to the experimentally determined value.


Assuntos
Cromo/isolamento & purificação , Solo/normas , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Resíduos Industriais , Purificação da Água/métodos
13.
Braz. j. biol ; Braz. j. biol;68(4): 751-762, Nov. 2008. ilus, graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-504492

RESUMO

Micro- and mesozooplankton were studied in the Sergipe estuary, northeastern Brazil, in order to assess the temporal variability in abundance and biodiversity under stressed conditions (urban pollution). Zooplankton samples and abiotic data were collected at one station during a full tidal cycle in July 2001 and in February 2002, corresponding to the rainy and dry seasons, respectively. The salinity regime was euhaline-polyhaline. Phosphate and dissolved oxygen were higher in July 2001, and nitrite, nitrate and ammonia in February 2002. Chlorophyll-a concentrations were low as a result of light limitation, with 1.18 ± 0.88 µg.m-3 in February and 1.53 ± 1.48 µg.m-3 in July. Fifty-nine zooplankton taxa were identified. Microzooplankton were abundant, mainly the tintinnid Favella ehrenbergii, and ranged from 18,649 ind.m-3 in July to 678,009 ind.m-3 in February. Mesozooplankton ranged from 1,537 ind.m-3 in July to 37,062 ind.m-3 in February and were dominated by barnacle nauplii in July and by copepods in February. The cluster analysis by taxa revealed the existence of three distinct groups: resilient species, characteristic of estuarine areas and occurring during all the year; species mainly more abundant in July (indicators of a healthier environmental condition); and species more abundant in February (tolerant to poor water quality).


O micro-e o mesozooplâncton foram estudados no estuário do rio Sergipe, Nordeste do Brasil para conhecer a variação temporal em abundância e biodiversidade sob condições de estresse. Amostras do zooplâncton e dados abióticos foram coletados em uma estação durante um ciclo completo de marés em julho de 2001 e em fevereiro de 2002, correspondendo aos períodos chuvoso e seco, respectivamente. O regime de salinidade variou de euhalino a polihalino. O fosfato e o oxigênio dissolvidos foram mais elevados em julho 2001, e o nitrito, o nitrato e a amônia, em fevereiro 2002. As concentrações de clorofila-a foram baixas devido à limitação da luz, com valores médios de 1,18 ± 0,88 µg.m-3 em fevereiro e 1,53 ± 1,48 µg.m-3 em julho. Foram identificados 59 taxa zooplanctônicos. O microzooplâncton foi abundante, principalmente o tintinídeo Favella ehrenbergii, que variou de 18.649 ind.m-3 em julho a 678.009 ind.m-3 em fevereiro. O mesozooplâncton variou de 1.537 ind.m-3 em julho a 37.062 ind.m-3 em fevereiro e foi dominado por náuplios de Cirripedia em julho e por Copepoda em fevereiro. A análise de agrupamento por taxa revelou a existência de três grupos: espécies resilientes, características de áreas estuarinas de ocorrência contínua; espécies que dominaram em julho (indicadores de uma melhor condição ambiental); e espécies mais abundantes em fevereiro (tolerantes à baixa qualidade da água).


Assuntos
Animais , Biodiversidade , Estações do Ano , Zooplâncton/fisiologia , Brasil , Densidade Demográfica , Dinâmica Populacional , Zooplâncton/classificação
14.
Braz J Biol ; 68(4): 751-62, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19197492

RESUMO

Micro- and mesozooplankton were studied in the Sergipe estuary, northeastern Brazil, in order to assess the temporal variability in abundance and biodiversity under stressed conditions (urban pollution). Zooplankton samples and abiotic data were collected at one station during a full tidal cycle in July 2001 and in February 2002, corresponding to the rainy and dry seasons, respectively. The salinity regime was euhaline-polyhaline. Phosphate and dissolved oxygen were higher in July 2001, and nitrite, nitrate and ammonia in February 2002. Chlorophyll-a concentrations were low as a result of light limitation, with 1.18 +/- 0.88 microg x m(-3) in February and 1.53 +/- 1.48 microg x m(-3) in July. Fifty-nine zooplankton taxa were identified. Microzooplankton were abundant, mainly the tintinnid Favella ehrenbergii, and ranged from 18,649 ind x m(-3) in July to 678,009 ind x m(-3) in February. Mesozooplankton ranged from 1,537 ind x m(-3) in July to 37,062 ind x m(-3) in February and were dominated by barnacle nauplii in July and by copepods in February. The cluster analysis by taxa revealed the existence of three distinct groups: resilient species, characteristic of estuarine areas and occurring during all the year; species mainly more abundant in July (indicators of a healthier environmental condition); and species more abundant in February (tolerant to poor water quality).


Assuntos
Biodiversidade , Estações do Ano , Zooplâncton/fisiologia , Animais , Brasil , Densidade Demográfica , Dinâmica Populacional , Zooplâncton/classificação
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