RESUMO
Salinity is harmful to crops when the concentration of soluble salts overcomes the salinity threshold of the crop, causing osmotic stress and limitations in plant growth. In this scenario, adopting tolerant cultivars is the most adequate strategy to minimize agricultural losses. However, the inheritance of tolerance depends on the genotype. From this perspective, this study assessed the tolerance to severe salt stress in 11 cotton cultivars based on gas exchange parameters and the free proline content. The cultivars were grown in a greenhouse and subjected to 34 days of saline irrigation (10 dS m-1), starting 45 days after seedling emergence (B1 phase). Plant growth was monitored weekly until the end of the salt stress period. The treatments consisted of a combination of two factors: eleven cultivars associated with two electrical conductivity levels of irrigation water (ECw: 0.3 and 10.0 dS m-1). The experimental design was in randomized blocks in a 11 × 2 factorial arrangement with three replications (66 plots), with the experimental unit consisting of one plant per plot. Salinity impacted plant growth, being reflected on the gas exchange and free proline data of most cultivars. However, BRS 286, FMT 705, BRS 416, and BRS Acácia, and CNPA 7MH withstood the effects of stress and osmotically adjusted to the salt stress conditions, thus minimizing the damage to growth. Those cultivars are the most indicated for improvement programs aiming at tolerance to salt stress based on the results found in this research.
Assuntos
Estresse Salino , Tolerância ao Sal , Plântula , Salinidade , ProlinaRESUMO
This study aimed to evaluate the productive performance, carcass yield, and intestinal morphometry of broiler chickens subjected to diets with the inclusion of buriti oil. Buriti oil is an energy food that can be used in chicken feed to replace soybean oil, which has a high cost in production, also has its anti-inflammatory, antioxidant, and antimicrobial properties, which can provide benefits in chicken feed. 180 male broilers of the Ross lineage were used, distributed in a completely randomized design with 3 treatments and 6 replicates of 10 birds per experimental unit. The experimental phase took place from 14 to 28 days and levels 0; 0.75 and 1.50% of buriti oil were added to the corn and soybean-based feed. It can be inferred that the buriti oil-based diets in the diet with insertion of levels of 0%, 0.75% and 1.50% did not differ significantly for the productive performance variables, but in relation to the productive yield there was a significant difference for carcass yield accompanied by greater disposition of abdominal fat, thigh and heart fat, a common effect in the use of oils. Although no statistical differences were observed for most of the variables in the assessment of intestinal morphometry, there was an increase in the crypt depth of the duodenum and ileum and an increase in the muscle layer of the duodenum and jejunum, which may have been caused by some injury to the intestine and not by direct effect of buriti oil. In the other variables there was no difference between treatments and it is concluded that buriti oil did not harm the performance, yield and intestinal morphometry of broiler chickens from 14 to 28 days of age.
Objetivou-se, com essa pesquisa, avaliar o desempenho produtivo, o rendimento de carcaça e a morfometria intestinal de frangos de corte com dietas submetidas à inclusão do óleo de buriti. Trata-se de um alimento energético que pode ser utilizado na alimentação de frangos visando substituir o óleo de soja, o qual apresenta alto custo na produção. O óleo de buriti ainda possui suas propriedades anti-inflamatórias, antioxidantes, antimicrobianas, podendo conferir benefícios na alimentação de frangos. Foram utilizados 180 frangos de corte machos, da linhagem Ross, distribuídos em um delineamento inteiramente ao acaso, com três tratamentos e seis repetições de 10 aves por unidade experimental. A fase experimental ocorreu de 14 a 28 dias, e os níveis 0%, 0,75% e 1,50% de óleo de buriti foram inseridos na ração à base de milho e soja. Pode-se inferir que as dietas à base de óleo de buriti na dieta com inserção dos níveis de 0%, 0,75% e 1,50% não diferiram significativamente para as variáveis de desempenho produtivo, mas, em relação ao rendimento produtivo, houve uma diferença significativa para o rendimento de carcaça, acompanhado de maior disposição de gordura abdominal, gordura de sobrecoxa e coração, efeito comum na utilização de óleos. Apesar de não serem observadas diferenças estatísticas para a maioria das variáveis na avaliação da morfometria intestinal, houve aumento na profundidade de cripta do duodeno e do íleo, bem como aumento da camada muscular do duodeno e do jejuno, que podem ter sido provocados por alguma injúria no intestino e não por efeito direto do óleo de buriti. Nas demais variáveis, não houve diferença entre os tratamentos, e conclui-se que o óleo de buriti não causou prejuízo ao desempenho, ao rendimento e à morfometria intestinal de frangos de corte no período de 14 a 28 dias de idade.
Assuntos
Animais , Masculino , Óleos de Plantas , Galinhas/anatomia & histologia , Arecaceae , Dieta/veterinária , Ração Animal/análiseRESUMO
OBJECTIVE: This study aimed to evaluate the effect of hepatic preconditioning with laser light in the presence of methylene blue (MB) in the liver ischemia-reperfusion injury process. METHOD: Forty male Wistar rats were divided into 8 experimental groups (n = 5). Saline (.5 mL) or MB (15 mg/kg) was injected intravenously (inferior vena cava). After 2 minutes, 660 nm laser light was applied at a dose of 112.5 DE. Fifteen minutes after the application of saline or MB, 1 hour partial ischemia followed by 15 minutes of reperfusion was applied when the rats were sacrificed. The mitochondrial function parameters (O2 consumption rates in states 3 and 4 and the respiratory control ratio), osmotic swelling, and determination of malondialdehyde were evaluated. Hepatic function was studied using the serum determination of the alanine aminotransferase and aspartate aminotransferase enzymes. RESULTS AND CONCLUSIONS: MB therapy alone showed the capacity of preserving the rate of oxygen consumption in the mitochondrial respiratory state of the group submitted to ischemia compared to the sham group. However, when combined with low-intensity laser therapy, it failed to replicate the relevant protective effects in relation to oxidative phosphorylation or the mitochondrial membrane ischemia/reperfusion injury. Whether or not MB was combined with laser treatment, it was shown to be efficient in reducing oxidative stress. In relation to alanine aminotransferase enzymes, whether or not laser treatment was combined with MB had a protective effect on the hepatic lesion, whereas in relation to aspartate aminotransferase enzymes only laser treatment was able to provide this protection.
Assuntos
Inibidores Enzimáticos/farmacologia , Lasers , Fígado/efeitos dos fármacos , Fígado/efeitos da radiação , Azul de Metileno/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/efeitos da radiação , Ratos , Ratos WistarRESUMO
The brown stink bug Euschistus heros is the most abundant species of the soybean-sucking bugs, and causes large economic losses. Applying different chemical groups of organosynthetic insecticides for its control increases the potential for resistance. Esterases are a group of enzymes that play a variety of roles in insects, and some of them are related to the metabolism of xenobiotics. The aim of this study was to analyze the esterase isoenzyme system of this species and investigate its response to Engeo™ Pleno (thiamethoxam and lambda-cyhalothrin), which is the most widely used pesticide in soybean crops. Two strains were analyzed: the EB strain, which had been free of insecticides for several generations; and the MA strain, which was collected in a location exposed to agrochemicals. By analyzing the polyacrylamide gel electrophoresis profile, seven different esterases in adults and nymphs of both strains were found. Eight gene loci were responsible for the synthesis of these enzymes. The differences in esterases between the two strains and enzyme changes in insects exposed to Engeo™ Pleno suggest that EST-2 and EST-4 are related to the metabolism of the agrochemical used and are mechanisms of resistance.
Assuntos
Esterases/genética , Hemípteros/enzimologia , Proteínas de Insetos/genética , Inseticidas/farmacologia , Nitrilas/farmacologia , Nitrocompostos/farmacologia , Oxazinas/farmacologia , Piretrinas/farmacologia , Tiazóis/farmacologia , Animais , Inibidores Enzimáticos/química , Esterases/antagonistas & inibidores , Esterases/metabolismo , Genes de Insetos , Loci Gênicos , Hemípteros/efeitos dos fármacos , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Dose Letal Mediana , Neonicotinoides , Ninfa/efeitos dos fármacos , Ninfa/enzimologia , Controle de Pragas , Especificidade por Substrato , TiametoxamRESUMO
The fall armyworm, Spodoptera frugiperda, is the pest that causes the greatest economic losses for both common corn and popcorn crops, and the use of resistant plant genotypes is an important tool for integrated pest management. The goal of the present study was to evaluate the damage caused by S. frugiperda on single-cross popcorn hybrids under field conditions with natural infestation as well as to study the effect of 11 popcorn hybrids on the S. frugiperda life cycle under laboratory conditions. A completely randomized block design with 4 replicates was used for the field experiment, and a completely randomized design with 10 replicates was used for the laboratory experiment. In the field experiment, the damage caused by fall armyworm, grain yield, and popping expansion were quantified, and a diallel analysis was performed to select the best hybrids. For the laboratory experiment, caterpillars were obtained from laboratory cultures kept on an artificial diet and were fed with leaves from the 11 hybrids. Hybrids P7.0 x P9.4, P7.1 x P9.6, P7.2.0 x P9.3, P7.4.0 x P9.1 and P7.4.1 x P9.4 exhibited negative specific combining ability for injury by fall armyworm and positive specific combining ability for yield and popping expansion. In the laboratory experiment, the hybrids influenced the mean larval stage duration, mean larval mass, final larval mass, pupal stage duration, mean pupal mass, and adult longevity.
Assuntos
Resistência à Doença/genética , Doenças das Plantas/genética , Spodoptera/crescimento & desenvolvimento , Zea mays/genética , Animais , Biomassa , Cruzamentos Genéticos , Feminino , Interações Hospedeiro-Parasita , Vigor Híbrido/genética , Hibridização Genética , Larva/crescimento & desenvolvimento , Larva/fisiologia , Estágios do Ciclo de Vida , Masculino , Controle Biológico de Vetores/métodos , Doenças das Plantas/parasitologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Reprodutibilidade dos Testes , Spodoptera/fisiologia , Zea mays/metabolismo , Zea mays/parasitologiaRESUMO
Objetivou-se analisar a viabilidade econômica da terceira ordenha em sistemas de produção de leite que utilizam ordenhadeira mecânica, do tipo circuito aberto, visando fornecer aos técnicos e pecuaristas informações que os auxiliem no processo de tomada de decisões. Especificamente pretendeu-se ainda: a) estimar o custo de uma ordenha; b) estimar, por meio de simulação, o custo da terceira ordenha; c) desenvolver uma equação matemática que permita estimar a quantidade mínima de leite produzido em duas ordenhas, a partir da qual será viável economicamente a realização da terceira ordenha. Os dados foram coletados em três sistemas de produção de leite, em uma rotina de duas ordenhas diárias, sendo realizadas três coletas de dados em cada um, perfazendo um total de nove. Considerando-se os dados médios, seria viável a realização da terceira ordenha se a produtividade média diária das vacas em lactação em duas ordenhas fosse igual ou superior a 38,13kg de leite. A equação matemática desenvolvida pode auxiliar o técnico e o pecuarista a estimarem a quantidade mínima de leite produzido por uma vaca em duas ordenhas, a partir da qual será viável economicamente a realização da terceira ordenha, com precisão e considerável rapidez.
This study aims to analyze the economic viability of the third milking in milk production systems using open circuit milking mechanics, aiming to provide technicians and farmers with information to help in the decision-making process. Specifically intend to a) estimate the cost of a milking; (b) estimate, by means of simulation, the cost of the third milking; (c) develop a mathematical equation that allows estimating the minimum amount of milk produced in two milkings, from which it will be economically feasible to hold the third milking. The data were collected in three milk production systems, in a routine of two milkings per day, with three collections of data in each, a total of nine collections. Considering the average data, it would be feasible to hold the third milking if the productivity of daily average lactating cows is equal or greater than 38.13 kg of milk. The mathematical equation developed may help the technician and the farmer to estimate the minimum quantity of milk produced by a cow in two milkings, from which it will be economically feasible to hold the third milking with precision and considerable speed.
Assuntos
Animais , Bovinos , Animais Domésticos , Economia , Leite , Bovinos/classificaçãoRESUMO
Objetivou-se analisar a viabilidade econômica da terceira ordenha em sistemas de produção de leite que utilizam ordenhadeira mecânica, do tipo circuito aberto, visando fornecer aos técnicos e pecuaristas informações que os auxiliem no processo de tomada de decisões. Especificamente pretendeu-se ainda: a) estimar o custo de uma ordenha; b) estimar, por meio de simulação, o custo da terceira ordenha; c) desenvolver uma equação matemática que permita estimar a quantidade mínima de leite produzido em duas ordenhas, a partir da qual será viável economicamente a realização da terceira ordenha. Os dados foram coletados em três sistemas de produção de leite, em uma rotina de duas ordenhas diárias, sendo realizadas três coletas de dados em cada um, perfazendo um total de nove. Considerando-se os dados médios, seria viável a realização da terceira ordenha se a produtividade média diária das vacas em lactação em duas ordenhas fosse igual ou superior a 38,13kg de leite. A equação matemática desenvolvida pode auxiliar o técnico e o pecuarista a estimarem a quantidade mínima de leite produzido por uma vaca em duas ordenhas, a partir da qual será viável economicamente a realização da terceira ordenha, com precisão e considerável rapidez.(AU)
This study aims to analyze the economic viability of the third milking in milk production systems using open circuit milking mechanics, aiming to provide technicians and farmers with information to help in the decision-making process. Specifically intend to a) estimate the cost of a milking; (b) estimate, by means of simulation, the cost of the third milking; (c) develop a mathematical equation that allows estimating the minimum amount of milk produced in two milkings, from which it will be economically feasible to hold the third milking. The data were collected in three milk production systems, in a routine of two milkings per day, with three collections of data in each, a total of nine collections. Considering the average data, it would be feasible to hold the third milking if the productivity of daily average lactating cows is equal or greater than 38.13 kg of milk. The mathematical equation developed may help the technician and the farmer to estimate the minimum quantity of milk produced by a cow in two milkings, from which it will be economically feasible to hold the third milking with precision and considerable speed.(AU)
Assuntos
Animais , Bovinos , Leite , Economia , Animais Domésticos , Bovinos/classificaçãoRESUMO
The expression enhancement by cytomegalovirus promoter and different intron A (IA) variants were evaluated in CHO-K1, HepG2, HEK-293 and COS-7 cells by assessing the levels of luciferase activity. This data along with mRNA levels measurement indicated that the construct harboring an IA variant with a 200-nucleotide deletion (Δ200) had the greatest impact on increasing luciferase expression among all constructs evaluated. Based on these results, we redesigned pCMV-IA variants and cloned them into plasmids expressing a humanized antibody. These plasmids were then used to transfect CHO-K1 cells. Production of the antibody was not augmented with the Δ200 promoter variant. The 600-nucleotide deletion (Δ600) and whole IA promoter variants expressed similar levels of the recombinant protein. These data indicate that the IA-based enhanced expression of transgenes depends on a small region within the intron.
Assuntos
Citomegalovirus/genética , Íntrons , Proteínas Recombinantes/biossíntese , Transgenes , Animais , Biotecnologia , Células CHO , Células COS , Chlorocebus aethiops , Cricetinae , Cricetulus , Expressão Gênica , Células HEK293 , Humanos , Luciferases/análise , Luciferases/genética , Luciferases/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/análise , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
Yoga is believed to have beneficial effects on cognition, attenuation of emotional intensity and stress reduction. Previous studies were mainly performed on eastern experienced practitioners or unhealthy subjects undergoing concomitant conventional therapies. Further investigation is needed on the effects of yoga per se, as well as its possible preventive benefits on healthy subjects. We investigated the effects of yoga on memory and psychophysiological parameters related to stress, comparing yoga practice and conventional physical exercises in healthy men (previously yoga-naïve). Memory tests, salivary cortisol levels and stress, anxiety, and depression inventories were assessed before and after 6 months of practice. Yoga practitioners showed improvement of the memory performance, as well as improvements in psychophysiological parameters. The present results suggest that regular yoga practice can improve aspects of cognition and quality of life for healthy individuals. An indirect influence of emotional state on cognitive improvement promoted by yoga practice can be proposed.
Assuntos
Yoga/psicologia , Adulto , Ansiedade/prevenção & controle , Cognição , Depressão/prevenção & controle , Humanos , Hidrocortisona/análise , Masculino , Memória , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Qualidade de Vida , Saliva/química , Estresse Psicológico/prevenção & controle , Adulto JovemRESUMO
A multiresidue and multiclass method based on liquid chromatography-tandem mass spectrometry for the determination of antibacterials was developed and validated for screening purposes. This method can be applied to commonly used drugs in veterinary medicine such as tetracyclines, quinolones and sulfonamides. Sample preparation consists in cell disruption with sand (previously purified and washed with EDTA 100 mM) followed by protein precipitation with acidified acetonitrile. Validation was conducted in accordance to European Union requirements (2002/657/EC) for qualitative methods covering detection capability (CCß), selectivity, specificity and stability. The method enabled the detection of 21 different drugs and had a false-compliant rate of <5% (ß error) at between 25% and 50% of the maximum residue levels established by legal authorities. The methodology was successfully applied to incurred poultry samples.
Assuntos
Antibacterianos/análise , Cromatografia Líquida/métodos , Resíduos de Drogas/análise , Contaminação de Alimentos/análise , Carne/análise , Espectrometria de Massas em Tandem/métodos , Animais , Brasil , Bovinos , Ensaios de Triagem em Larga Escala , Limite de Detecção , Aves Domésticas , Espectrometria de Massas por Ionização por Electrospray/métodos , Drogas Veterinárias/análiseRESUMO
There is much evidence to support that Mocis latipes larvae (Guenèe, 1852) are the most dangerous pasture pest and usually cause large environmental losses. However, no studies have been carried out to identify the instars during which this moth causes the most damage to the environment. Here we calculate M. latipes larval energy budget to assess its consumption across all instars and estimate the consumption/amount of plant biomass required to complete its larval development. Assimilation, respiration, consumption, excretion, gross growth efficiency and net growth efficiency were calculated. Pearson correlations were used to identify the best predictors that influenced larval growth and weight. Across all instars consumption increased exponentially, especially during the last phase. M. latipes larvae consumed ca 13.8% of total food from the first to the fifth instar, whereas during the sixth instars these larvae consumed ca 72.6%. Results also show that the best gross growth and net growth efficiency were obtained when larvae reached the fifth instar. The results also show that one larva of Mocis latipes consumes 1.02 g (dry weight) of Paspalum maritimum (Trin) in 19 days. Overall, our results indentified the sixth instar as the most destructive instar of this insect. Thus, once we know the most destructive instars of this pest, measures can be taken to disable M. latipes larval development and consequently stop their increase in plant consumption, reducing ecological and economic damage. This knowledge may eventually lead to reduced agricultural damage and contribute to sustainable farming strategies.
Assuntos
Estágios do Ciclo de Vida/fisiologia , Mariposas/crescimento & desenvolvimento , Agricultura , Animais , Comportamento Excretor Animal/fisiologia , Comportamento Alimentar/fisiologia , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Mariposas/classificação , Mariposas/fisiologiaRESUMO
There is much evidence to support that Mocis latipes larvae (Guenèe, 1852) are the most dangerous pasture pest and usually cause large environmental losses. However, no studies have been carried out to identify the instars during which this moth causes the most damage to the environment. Here we calculate M. latipes larval energy budget to assess its consumption across all instars and estimate the consumption/amount of plant biomass required to complete its larval development. Assimilation, respiration, consumption, excretion, gross growth efficiency and net growth efficiency were calculated. Pearson correlations were used to identify the best predictors that influenced larval growth and weight. Across all instars consumption increased exponentially, especially during the last phase. M. latipes larvae consumed ca 13.8 percent of total food from the first to the fifth instar, whereas during the sixth instars these larvae consumed ca 72.6 percent. Results also show that the best gross growth and net growth efficiency were obtained when larvae reached the fifth instar. The results also show that one larva of Mocis latipes consumes 1.02 g (dry weight) of Paspalum maritimum (Trin) in 19 days. Overall, our results indentified the sixth instar as the most destructive instar of this insect. Thus, once we know the most destructive instars of this pest, measures can be taken to disable M. latipes larval development and consequently stop their increase in plant consumption, reducing ecological and economic damage. This knowledge may eventually lead to reduced agricultural damage and contribute to sustainable farming strategies.
Inúmeras evidências indicam a larva de Mocis latipes (Guenèe, 1852) como uma das pragas de pastagem mais perigosas e que comumente causam grandes perdas ambientais. Entretanto, nenhum estudo foi feito para identificar qual a fase de desenvolvimento em que o dano ao ambiente é maior. Neste trabalho, nós calculamos o balanço energético larval de M. latipes para descobrir o consumo em cada instar e estimar o consumo requerido para completar o desenvolvimento larval. A assimilação, respiração, excreção, consumo e os coeficientes, bruto e líquido, do crescimento foram calculados. Correlações de Pearson foram usadas para identificar os preditores que mais influenciavam o crescimento da larva. Resultados indicaram que o consumo aumentou exponencialmente durante os instares, especialmente durante o último instar. Larvas de M. latipes consumiram aproximadamente 13,8 por cento do recurso alimentar total entre o primeiro e o quinto instar, enquanto que no sexto instar consumiram 72,6 por cento. Os resultados também indicaram que o consumo bruto e o consumo líquido foram maiores nos últimos instares. Também se verificou que apenas uma larva consumiu 1,02 g de Paspalum maritimum (Poaceae) em 19 dias. Em resumo, nossos resultados identificaram o sexto instar como o mais destrutivo. Uma vez que se conheça o instar mais destrutivo, medidas mais eficazes podem ser tomadas para inibir o desenvolvimento larval de M. Latipes e o crescimento significativo do seu consumo e, consequentemente, reduzir danos ao ambiente. Este conhecimento pode, eventualmente, contribuir para reduzir danos à agricultura e contribuir para seu desenvolvimento sustentável.
Assuntos
Animais , Feminino , Masculino , Estágios do Ciclo de Vida/fisiologia , Mariposas/crescimento & desenvolvimento , Agricultura , Comportamento Excretor Animal/fisiologia , Comportamento Alimentar/fisiologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Mariposas/classificação , Mariposas/fisiologiaRESUMO
There is much evidence to support that Mocis latipes larvae (Guenèe, 1852) are the most dangerous pasture pest and usually cause large environmental losses. However, no studies have been carried out to identify the instars during which this moth causes the most damage to the environment. Here we calculate M. latipes larval energy budget to assess its consumption across all instars and estimate the consumption/amount of plant biomass required to complete its larval development. Assimilation, respiration, consumption, excretion, gross growth efficiency and net growth efficiency were calculated. Pearson correlations were used to identify the best predictors that influenced larval growth and weight. Across all instars consumption increased exponentially, especially during the last phase. M. latipes larvae consumed ca 13.8 percent of total food from the first to the fifth instar, whereas during the sixth instars these larvae consumed ca 72.6 percent. Results also show that the best gross growth and net growth efficiency were obtained when larvae reached the fifth instar. The results also show that one larva of Mocis latipes consumes 1.02 g (dry weight) of Paspalum maritimum (Trin) in 19 days. Overall, our results indentified the sixth instar as the most destructive instar of this insect. Thus, once we know the most destructive instars of this pest, measures can be taken to disable M. latipes larval development and consequently stop their increase in plant consumption, reducing ecological and economic damage. This knowledge may eventually lead to reduced agricultural damage and contribute to sustainable farming strategies.(AU)
Inúmeras evidências indicam a larva de Mocis latipes (Guenèe, 1852) como uma das pragas de pastagem mais perigosas e que comumente causam grandes perdas ambientais. Entretanto, nenhum estudo foi feito para identificar qual a fase de desenvolvimento em que o dano ao ambiente é maior. Neste trabalho, nós calculamos o balanço energético larval de M. latipes para descobrir o consumo em cada instar e estimar o consumo requerido para completar o desenvolvimento larval. A assimilação, respiração, excreção, consumo e os coeficientes, bruto e líquido, do crescimento foram calculados. Correlações de Pearson foram usadas para identificar os preditores que mais influenciavam o crescimento da larva. Resultados indicaram que o consumo aumentou exponencialmente durante os instares, especialmente durante o último instar. Larvas de M. latipes consumiram aproximadamente 13,8 por cento do recurso alimentar total entre o primeiro e o quinto instar, enquanto que no sexto instar consumiram 72,6 por cento. Os resultados também indicaram que o consumo bruto e o consumo líquido foram maiores nos últimos instares. Também se verificou que apenas uma larva consumiu 1,02 g de Paspalum maritimum (Poaceae) em 19 dias. Em resumo, nossos resultados identificaram o sexto instar como o mais destrutivo. Uma vez que se conheça o instar mais destrutivo, medidas mais eficazes podem ser tomadas para inibir o desenvolvimento larval de M. Latipes e o crescimento significativo do seu consumo e, consequentemente, reduzir danos ao ambiente. Este conhecimento pode, eventualmente, contribuir para reduzir danos à agricultura e contribuir para seu desenvolvimento sustentável.(AU)
Assuntos
Animais , Metabolismo Energético/fisiologia , Mariposas/crescimento & desenvolvimento , Meio Ambiente/prevenção & controle , Larva/crescimento & desenvolvimento , Controle de Pragas/métodosRESUMO
The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm). The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7% of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.
Assuntos
Ecossistema , Caramujos/crescimento & desenvolvimento , Animais , Biometria , Brasil , Humanos , Umidade , Densidade Demográfica , Estações do Ano , Caramujos/anatomia & histologia , TemperaturaRESUMO
The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm). The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7 percent of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.
A relação peso comprimento e o fator de condição têm sido bastante explorados em pesquisas envolvendo caracóis para obter o índice de condição física em populações e avaliar a condição do habitat. Neste trabalho, nosso objetivo foi descrever que variáveis influenciam os parâmteros biométricos e o bem estar de Achatina fulica em uma recente introdução. De novembro de 2001 a novembro de 2002, amostras mensais desses caracóis foram coletadas na cidade de Lauro de Freitas (Bahia), Brasil. Em seguida, os caracóis foram acondicionados em laboratório e foram obtidos o tamanho da concha e o seu peso. A partir desses dados a curva potencial e o fator de condição foram calculados. Cinco variáveis ambientais foram consideradas: amplitude de temperatura, temperatura média, humidade, precipitação e densidade humana. Regressões múltiplas foram usadas para gerar modelos preditivos através do critério de seleção e logo foram ordenados utilizando o critério de Akaíke. Regressões parciais foram usadas para obter os coeficientes de determinação do clima e fatores humanos. Um total de 1460 indivíduos foram coletados, apresentando uma amplitude de crescimento de concha entre 4,9 a 102,5 mm (média 42,18 mm). A relação entre o crescimento total e o peso revelou que A. fulica apresentou um crescimento alométrico negativo. Regressões simples indicaram que a umidade teve uma influencia significativa sobre o tamanho total e o peso. A amplitude de temperatura foi a variável que mais influenciou o fator de condição. Os modelos de regressão múltipla indicaram que os fatores climáticos e humanos explicaram uma pequena porção da variança, no entanto explicou 55,8 por cento da variância do fator de condição. Consequentemente, acreditamos que o bem estar e os parâmetros biométricos de A. Fulica podem ser influenciados por fatores climáticos e humanos.
Assuntos
Animais , Humanos , Ecossistema , Caramujos/crescimento & desenvolvimento , Biometria , Brasil , Umidade , Densidade Demográfica , Estações do Ano , Caramujos/anatomia & histologia , TemperaturaRESUMO
The goal of this study was to document the distribution and establishment A. fulica such as their feeding preference and behavior in situ. The study was carried out at the city of Lauro de Freitas, Bahia state, Brazil, between November 2001 and November 2002. We used catch per unit effort methods to determine abundance, distribution, habitat choice and food preferences. The abundance and distribution of A. fulica was most representative in urban area, mainly near to the coastline. Lots and house gardens were the most preferred sites during active hours. The results indicated that A. fulica started their activity at the end of the evening and stopped in mid-morning. Their preferred food were vascular plants such as Hibiscus syriacus, Ricinus communis, Carica papaya, Galinsonga coccinea, Lippia alba, Ixora coccinea, Musa parasidisiaca, Mentha spicata and Cymbopogon citrates. Our results indicate that A. fulica are well adapted and established in this city and modified environments facilitate their establishment and dispersion. However, human perturbation, such as clearance of lots could be limiting for the persistence of A. fulica populations.
O objetivo deste estudo foi documentar a distribuição e o estabelecimento de Achatina fulica, assim como sua preferência alimentar e aspectos comportamentais in situ. Esta pesquisa foi desenvolvida na cidade de Lauro de Freitas, Estado da Bahia, Brasil, durante os meses de novembro de 2001 a novembro de 2002. Usamos o método de esforço de captura determinado por homem/hora para calcular a abundância e distribuição, habitats preferidos, além de preferência alimentar. Vimos que a abundância e distribuição de A. fulica foram mais representativas em áreas urbanas, sobretudo cerca da linha de costa. Os terrenos e jardins de casas foram os locais preferidos pelos caracóis quando estavam em atividade. Os resultados indicaram que os caracóis A. fulica iniciam sua atividade no final da tarde e hibernam no meio da manhã. A comida preferida destes caracóis foram plantas vasculares como Hibiscus syriacus, Ricinus Communis, Carica papaya, Galinsonga coccinea, Lippia alba, Ixora coccinea, Musa parasidisiaca, Mentha spicata and Cymbopogon citrates. Nossos dados sugerem que o A. fulica está plenamente adaptado e estabelecido nesta cidade e, também, que ambientes modificados facilitam seu estabelecimento e dispersão. Entretanto, a perturbação humana, como a limpeza de terrenos pode ser um fator limitante para a persistência da população de A. fulica.
Assuntos
Animais , Comportamento Alimentar/fisiologia , Caramujos/fisiologia , Brasil , Densidade Demográfica , Dinâmica Populacional , Estações do AnoRESUMO
Studies have shown a time-of-day of training effect on long-term explicit memory with a greater effect being shown in the afternoon than in the morning. However, these studies did not control the chronotype variable. Therefore, the purpose of this study was to assess if the time-of-day effect on explicit memory would continue if this variable were controlled, in addition to identifying the occurrence of a possible synchronic effect. A total of 68 undergraduates were classified as morning, intermediate, or afternoon types. The subjects listened to a list of 10 words during the training phase and immediately performed a recognition task, a procedure which they repeated twice. One week later, they underwent an unannounced recognition test. The target list and the distractor words were the same in all series. The subjects were allocated to two groups according to acquisition time: a morning group (N = 32), and an afternoon group (N = 36). One week later, some of the subjects in each of these groups were subjected to a test in the morning (N = 35) or in the afternoon (N = 33). The groups had similar chronotypes. Long-term explicit memory performance was not affected by test time-of-day or by chronotype. However, there was a training time-of-day effect [F (1,56) = 53.667; P = 0.009] with better performance for those who trained in the afternoon. Our data indicated that the advantage of training in the afternoon for long-term memory performance does not depend on chronotype and also that this performance is not affected by the synchronic effect.
Assuntos
Ritmo Circadiano/fisiologia , Memória/fisiologia , Reconhecimento Psicológico/fisiologia , Testes de Associação de Palavras , Adolescente , Adulto , Feminino , Humanos , MasculinoRESUMO
The purpose of this study is to report a case of infra-renal aorta agenesis with emphasis on the MR angiography (MRA) findings. A 66-year-old woman presented with urinary complaints. Pelvic and abdominal ultrasound showed hydronephrosis secondary to ureteral lithiasis; the distal portion of the abdominal aorta was not identified. Abdominal CT showed that the infra-renal portion of the abdominal aorta was apparently absent. MRI and MRA demonstrated that, after the origin of the renal arteries, the abdominal aorta spontaneously terminated in two lumbar hypertrophic arteries. In addition, MRA showed a dilated superior mesenteric artery that formed a vascular loop, which continued posterior and inferiorly towards the posterior pelvic region. In this region, it bifurcated and formed internal iliac branches, which were responsible for the arterial supply of the pelvis. In conclusion, MRA allows for precise evaluation of patients with infra-renal abdominal aorta agenesis. Although it is a rare entity, radiologists should be able to recognize it in ultrasound, CT and MRI studies.