Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Mar Environ Res ; 169: 105353, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33991938

RESUMO

Encapsulated development with extraembryonic yolk may lead to competition for nutrients within egg capsules. In this research, different degrees of competition among embryos in subtidal egg capsules of Acanthina monodon resulted in considerable differences in hatching size. For newly hatched juveniles, individuals hatching from less crowded egg capsules showed better survival, larger SL, higher rates of oxygen consumption, and higher rates of food consumption. However, by 28 days after hatching, the largest surviving juveniles were the best-performing individuals, regardless of the initial embryo density within the capsules. In summary, more crowded egg capsules resulted in poorer survival. These findings may help to explain the variability seen in juvenile success in some field populations; much of that variation may reflect stressful experiences that the new recruits have had during the early stages of their encapsulated development.


Assuntos
Gastrópodes , Animais , Cápsulas , Consumo de Oxigênio
2.
PLoS One ; 16(4): e0250937, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33930071

RESUMO

Active predators obtain energy and nutrients from prey through complex processes in which the energy gained must exceed the energy invested in finding and ingesting the prey. In addition, the amount of energy available will vary with the prey that are selected for consumption. The muricid gastropod Acanthina monodon inhabits rocky shores, where it routinely feeds on the mytilids Semimytilus algosus and Perumytilus purpuratus. In this study, S. algosus was highly preferred by the predator (over 90% were eaten) versus P. purpuratus (only 9% were eaten) when offered a mixed diet. The energetic cost of attacking one S. algosus individual was 91 J bivalve-1 while for P. purpuratus it was slightly higher: 95 J bivalve-1. Also, whereas A. monodon required on average 19 h to consume S. algosus, successful attacks on P. purpuratus required about 32% more time (25 h). In addition, a longer resting time was needed by the predator after preying on P. purpuratus before it initiated another attack. Moreover, the active metabolic costs associated with successfully attacking the prey increased 3.2 times over the basal metabolic costs when attacking S. algosus, but only by 2.5 times when attacking P. purpuratus. The calculations associated with preying on each species showed that the energetic gain per unit time likely accounts for the predator's preference for attacking S. algosus, even though predation on both species provided net energy gains for the predator. However, as S. algosus occurs seasonally at our study site, P. purpuratus would probably also be consumed due to its constant availability throughout the whole year.


Assuntos
Carnívoros/fisiologia , Ecossistema , Cadeia Alimentar , Gastrópodes/fisiologia , Mytilidae/fisiologia , Comportamento Predatório/fisiologia , Animais , Especificidade da Espécie
3.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 947-954, May-June, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1129662

RESUMO

The objective of this study was to determine factors affecting phenotypic characteristics related to milk production and reproductive efficiency of dairy buffalo. Phenotypic records of 2,459 Murrah, Mediterranean and crossbred buffaloes from the Embrapa Eastern Amazônia herd, from 1969 to 2013 were used. Traits included: total milk production during lactation (TMP), milk production corrected for 305 days (P305); cow weight at calving (CW), fat milk percentage (F), age at first calving (AFC), calving interval (CI), calf birth weight (BW), as well as lactation (LP) and service periods (SP). Most traits were affected by genetic group as well as year and season or interaction between them. Genetic group affected F, CI, SP and CW. Very young and older cows showed poorer production traits. There was interaction between season and year for F, CI and CW. Correlations traits were generally medium to low. The principal component analysis showed that higher fat milk percentage was associated with higher percentage of Murrah breed, longer lactation period and older cows. Phenotypic characteristics in buffaloes reared in the Brazilian Amazon were significantly affected by genetic and management factors. This information can be used to help build sustainable production systems for the region and guide farmer decisions.(AU)


O objetivo deste estudo foi determinar os fatores que afetam as características fenotípicas relacionadas à produção de leite e a eficiência reprodutiva de búfalas leiteiras. Foram utilizados os registros fenotípicos de 2.459 búfalas das raças Murrah, Mediterrâneo e seus cruzamentos do rebanho da Embrapa Amazônia Oriental, de 1969 a 2013. As características incluídas foram: produção total de leite durante a lactação (PTL), produção de leite corrigida para 305 dias (P305), peso da búfala ao parto (PV), percentual de gordura do leite (G), idade ao primeiro parto (IPP), intervalo entre partos (IP), peso do bezerro ao nascimento (PN), assim como os períodos de lactação (PL) e de serviço (PS). A maioria das características foi afetada pelo grupo genético, bem como pelo ano e pela estação ou pela interação entre eles. O grupo genético afetou o G, IP, PS e PV. Búfalas muito jovens e mais velhas mostraram características de produção mais baixas. Houve interação entre estação e o ano para G, IP e PV. As correlações entre as características foram geralmente de médias a baixas. A análise de componentes principais mostrou que a maior porcentagem de gordura no leite foi associada com a maior porcentagem de sangue Murrah, com o maior período de lactação e com búfalas mais velhas. As características fenotípicas das búfalas criadas na Amazônia brasileira foram significativamente afetadas por fatores genéticos e de manejo. Essas informações podem ser usadas para ajudar a construir sistemas de produção sustentáveis para a região e orientar as decisões dos produtores.(AU)


Assuntos
Animais , Feminino , Fenótipo , Búfalos/genética , Leite
4.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1712-1718, set.-out. 2019. tab
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1038679

RESUMO

The objective of this study was to evaluate genetic aspects related to production and reproductive efficiency of Murrah and Mediterranean buffaloes and their crosses. A ranking of bulls from Embrapa Eastern Amazonia was also composed to guide assisted mating. Birth records of 2,322 Murrah, Mediterranean, and crossbred buffaloes from the Embrapa Eastern Amazon herd, from 1953 to 2013, as well as information on production and reproductive traits were used. Genetic analyzes were performed in the WOMBAT software using the animal model with two-trait analysis. While heritability (h2) for total milk production (TMP) and fat milk percentage (F) were generally high, for reproductive traits h2 tended to be low. Genetic correlations for TMP with the other traits were low and negative, except for TMP with calving interval (CI) and service period (SP) in the Mediterranean breed and with age at first calving (AFC) and SP in crossbred, which were positive and high. Bull 1001 had high predicted transmitting ability (PTA) for TMP, so it should transmit a greater volume of milk to his offspring, although it had a lower PTA for F. There was sufficient variability within the herd to work with genetic management for both production and reproductive efficiency.(AU)


O objetivo deste estudo foi avaliar os aspectos genéticos relacionados à produção e à eficiência reprodutiva de búfalas das raças Murrah, Mediterrâneo e suas cruzas. Uma classificação de touros da Embrapa Amazônia Oriental também foi composta para orientar os cruzamentos assistidos. Foram utilizados 2.322 registros de nascimento de búfalas das raças Murrah, Mediterrâneo e cruzadas do rebanho da Embrapa Amazônia Oriental, de 1953 a 2013, bem como características produtivas e reprodutivas. As análises genéticas foram realizadas pelo software Wombat, utilizando-se o modelo animal com análise de duas características. Enquanto a herdabilidade (h 2 ) para a produção total de leite (PTL) e para a porcentagem de gordura (G) foi alta, para as características reprodutivas a h 2 tendeu a ser baixa. As correlações genéticas da PTL com as demais características foram baixas e negativas, exceto para a PTL com intervalo entre partos (IP) e período de serviço (PS) na raça Mediterrâneo e com idade ao primeiro parto (IPP) e PS nas cruzadas, que foram positivas e altas. O touro 1001 apresentou alta capacidade de transmissão predita (CTP) para a PTL, então deve transmitir um maior volume de leite para seus descendentes, embora com um menor conteúdo transmissível de CTP para G. Portanto, existe variabilidade suficiente dentro do rebanho para trabalhar com o manejo genético para a produção e a eficiência reprodutiva.(AU)


Assuntos
Animais , Cruzamento/estatística & dados numéricos , Búfalos/genética , Técnicas Reprodutivas/veterinária , Correlação de Dados
5.
Genet Mol Res ; 15(3)2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27706739

RESUMO

Water buffaloes (Bubalus bubalis) are quite well adapted to climatic conditions in the Amazon, and in this biome, they are noted for the considerable amount of meat and milk they produce and how hard they are able to work. Because of a lack of research dedicated to improving the rearing of buffaloes in the Amazon, the objective of this study was to genetically characterize the Murrah and Mediterranean breeds, as well as a mixed-breed population, based on polymorphisms in the diacylglycerol O-acyltransferase 1 gene (DGAT1), and associate the genotypes with milk production. By using the polymerase chain reaction-single-strand conformation polymorphism technique, the alleles A (0.79), B (0.20), and D (0.01) were found in the Murrah breed. In the Mediterranean and mixed-breed buffaloes, we found alleles A (0.69) and (0.77) and B (0.31) and (0.23), respectively. The Murrah breed had the genotypes AA (0.63), AB (0.29), BB (0.05), and AD (0.03), and the Mediterranean and mixed-breed buffaloes had the genotypes AA (0.44) and (0.61), AB (0.50) and (0.31), and BB (0.06) and (0.08), respectively. For the Murrah, Mediterranean, and mixed-breed buffaloes, respectively, the expected heterozygosity values were 0.34, 0.43, and 0.35, the inbreeding coefficients were 0.78, -0.15, and 0.17, and the Hardy-Weinberg probabilities were 0.70, 0.67, and 0.52. The genotypes evaluated did not have an effect on milk production; however, the single nucleotide polymorphisms can be used in studies on genetic variability.


Assuntos
Búfalos/genética , Diacilglicerol O-Aciltransferase/genética , Variação Genética , Alelos , Animais , Diacilglicerol O-Aciltransferase/metabolismo , Genótipo , Leite/metabolismo , Polimorfismo de Nucleotídeo Único/genética
6.
Arq Neuropsiquiatr ; 59(2-A): 206-9, 2001 Jun.
Artigo em Português | MEDLINE | ID: mdl-11400026

RESUMO

The Virchow-Robin spaces (VRS) are subpial invaginations making a tubular revestment scabbard that contains a vase between the subarachnoid and subpial spaces. The magnetic resonance imaging (MRI) is the only imaging method able for evaluate this anatomic detail. We studied the possible association between dilated VRS and migraine. Seventy patients with ages ranging from 13 to 54 years (mean, 36.5 years), with clinical diagnosis of migraine were studied and compared with a control group, without past of headache, composed by the same number of patients with ages ranged from 14 to 64 years (mean, 42 years). We observed widening of VRS in 28 cases (40%) of the migraine patients. In the control group this feature was demonstrated in only 5 cases (7.1%). Alert for the importance of detecting and recognizing the VRS, as well as, the differentiation from lacunar infarctions and choroid fissure cysts.


Assuntos
Artérias Cerebrais/patologia , Transtornos de Enxaqueca/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Dilatação Patológica/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Espaço Subaracnóideo/irrigação sanguínea
7.
Arq Neuropsiquiatr ; 59(2-A): 210-3, 2001 Jun.
Artigo em Português | MEDLINE | ID: mdl-11400027

RESUMO

The purpose of this study is to evaluate morphological and signal intensity changes in the hippocampus in patients with medically intractable temporal lobe epilepsy. We studied 8 patients with mesial temporal sclerosis using a 1.5 -T MR and the following sequences Spin Eco- SE, Fast Spin Echo- FSE, Fluid Attenuation Inversion Recovery Echo Planar Imaging--FLAIR-EPI. We noticed a sensitive increase signal intensity on FLAIR- EPI sequences, particularly, in coronal images, than on SE and FSE sequences. The STIR sequence showed a cortical hippocampus atrophy in half of the cases, in whom signal abnormalities were present.


Assuntos
Imagem Ecoplanar , Epilepsia do Lobo Temporal/patologia , Hipocampo/patologia , Humanos , Aumento da Imagem , Esclerose/patologia
8.
Arq Neuropsiquiatr ; 59(2-A): 266-9, 2001 Jun.
Artigo em Português | MEDLINE | ID: mdl-11400040

RESUMO

We report a case of sarcoidosis in a 21 years old male with history of headache since he was three years old, with absence of abnormalities in a brain computerized tomography (CT). Brain magnetic resonance (MRI) disclosed a meningeal involvement with intense and homogeneous enhancement of the right fronto-temporal convexity and anterior third of the interhemispheric fissure. The brain MRI is more sensitive than brain CT and is the most appropriate method for the evaluation of meningeal and parenchymatous lesions, as well as monitoring the response to therapy and patients follow up.


Assuntos
Encefalopatias/diagnóstico , Sarcoidose/diagnóstico , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Técnicas Estereotáxicas
9.
Arq Neuropsiquiatr ; 59(2-A): 280-2, 2001 Jun.
Artigo em Português | MEDLINE | ID: mdl-11400044

RESUMO

We report a casual finding of a sphenoethmoidal meningoencephaloventriculocele in an adult patient that the tomography finding was misinterpreted as an expansive neoplastic lesion with malignant features. We alert for the rare site of localization of this malformative pathology.


Assuntos
Encefalocele/diagnóstico , Meningocele/diagnóstico , Seio Esfenoidal , Adulto , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios X
10.
Rev Saude Publica ; 31(6): 556-65, 1997 Dec.
Artigo em Português | MEDLINE | ID: mdl-9629710

RESUMO

OBJECTIVES: To evaluate the reliability, magnitude and direction of the resulting bias in the application of a screening instrument for mental disorders by considering proxy informants in comparison to primary informants. METHODS: Data are taken from a general morbidity community-based survey carried out in 520 randomly selected households of an industrial area of the Metropolitan Region of Salvador, the capital of Bahia state, Brazil. During the pilot phase, the first 70 families of the total sample were asked to participate in the evaluation of research instruments. The Questionnaire of Adult Psychiatric Morbidity, QAPM, consists of 44 questions about psychiatric symptoms widely used in Brazil. The husbands and wives of the selected families answered QAPM questions regarding themselves and their respective partners. One family refused to participate. The Kappa index was estimated for each QAPM question. To assess the magnitude and direction of bias, the proportional variation of prevalence was estimated from proxy and primary respondents. Each informant was analyzed as a primary informant when answering about his/her own symptoms and as a proxy informant when answering those about his/her partner. RESULTS: Proxy informants as compared to primary informants show weak reliability, as measured by the Kappa Index, particularly when husbands reported on their wives' symptoms. An overall underestimation of prevalence estimates was found, which reveals the potential negative bias with the use of proxy informants for psychological symptoms. No bias was found for only two questions (lack of appetite and globus hystericus) when women were taken as proxy informants for their husbands. In addition, departures of proxy informants from primary informant-based estimates were greater among men than to women. CONCLUSIONS: Proxy informants underestimate the occurrence of psychological symptoms in this community-based study. When the feasibility of a research project, based on the QAPM depends on the use of proxies, wives may be recommended as better informants than their husbands.


Assuntos
Programas de Rastreamento , Transtornos Mentais/epidemiologia , Inquéritos e Questionários , Adolescente , Adulto , Viés , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA