66 research outputs found

    Respostas fisiológicas de cabras leiteiras criadas na região litorânea do estado do Ceará.

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    Esse estudo foi conduzido no sitio Acuã na região litorânea do estado do Ceará no período de junho a dezembro de 2000 com o objetivo de avaliar as variações nas concentrações hormonais de T3 e T4 de cabras leiteiras em diferentes épocas de coletas. Foram utilizadas 22 fêmeas caprinas das raças Saanen (n=1O), 1/2 Murciana (n=8), Alpina Americana (n=4) com idade variando entre I a 5 anos e entre a 1a e 4a parição. Na indução do estro foram utilizadas esponjas intra - vaginais de cloprostenol e gonadotrofina eqüina. Não houve efeito significativo entre as variáveis meteorológicas com a temperatura retal e a freqüência respiratória. As concentrações plasmáticas dos hormônios T4 não foram significativas entre raças. O nível hormonal de T3 foi menor nos animais das raças Alpinas Americanas e os valores da TR e FR foram maiores que nas cabras da raça Saanen. Essa resposta adaptativa dos animais da raça Saanen deve-se a aclimatação as condições ambientais da região. Os níveis séricos dos hormônios tireoideanos foram afetados pelas variáveis ambientais porém os animais mantiveram a homeotermia não ocorrendo o estresse térmico.Disponível em separata

    Plant proton pumps as markers of biostimulant action.

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    ABSTRACT A standard protocol to evaluate the effects of biostimulants on plant physiology is still lacking. The proton pumps present in the vacuolar and plasma membranes are the primary agents responsible for the regulation of the electrochemical gradient that energizes the nutrient uptake system and acid growth mechanism of plant cells. In this study, two of these enzymes were characterized as biochemical markers of biostimulant activity. A simple and fast protocol based on the degree of root acidification using a pH sensitive dye and the Micro-Tom tomato as a plant model is proposed as an efficient methodology to prove the efficacy of biostimulants that are claimed to improve nutrient acquisition and root growth. The results agree with the data from more conventional, expensive and time-consuming proton pump assays. A direct correlation was found between plasmalemma proton-adenosine triphosphatase (H+-ATPase) activation and the amount of rhizosphere acidification observed in the bromocresol gel. Moreover, roots of the diageotropica (dgt) Micro-Tom plants, defective in auxin responses, barely acidify bromocresol purple gel even in the presence of indole-3-acetic acid (IAA, 1 μM). The biostimulant TEA (vermicompost water extract, 25 %) enhances proton extrusion by 40 % in wild type (WT) plants, but no effect was induced in dgt plants. These results reinforce the notion that the class of biostimulant known as humic substances stimulates plant proton pumps and promotes root growth by exerting an auxin-like bioactivity and establish the usefulness of an economically and technically feasible assay to certify this kind of biostimulant

    Genetic diversity and population structure of different varieties of Morada Nova hair sheep from Brazil.

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    Made available in DSpace on 2018-07-12T01:02:04Z (GMT). No. of bitstreams: 1 gmr2908.pdf: 709034 bytes, checksum: 687aba91750471851cf3620e3428c4ab (MD5) Previous issue date: 2015-01-21bitstream/item/116096/1/gmr2908.pd

    Características termorreguladoras e desempenho de cabras leiteiras no terço inicial da lactação em clima tropical.

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    Resumo: Teve-se como objectivo avaliar o comportamento de características termorreguladoras, a condição corporal e a produção de leite no início da lactação de 45 cabras de diferentes tipos raciais (15 da raça Saanen, 15 cruzadas Sem Padrão Racial Definido (SPRD) x Murciana e 15 Alpinas Americanas). Foram tomadas a temperatura retal, a freqüência respiratória, o escore da condição corporal a produção diária de leite e as concentrações plasmáticas de triiodotironina (T3) e tiroxina (T4) avaliados até os 36 dias da lactação. As concentrações de T3 e T4 foram obtidas pelo método de radioimunoensaio. As variáveis meteorológicas foram registradas às 15 h, no mesmo horário da coleta dos dados fisiológicos. Os resultados obtidos indicaram que as cabras da raça Alpina Americana tiveram as maiores temperaturas retais e frequencias respiratórias, além de menores concentrações de triiodotironina e tiroxina, associados a menor produção de leite e condição corporal possivelmente como reflexo de menor adaptação ao clima. As cabras Saanen e _ Murciana SPRD apresentaram menores temperaturas retais e frequencias respiratórias, maior escore da condição corporal e concentrações séricas de triiodotironina e tiroxina. As temperaturas retais foram iguais entre os grupos genéticos _ SPRD x _ Murciana e diferente para as cabras saanen. No terço inicial de lactação animais mestiços leiteiros juntamente com as cabras Saanen, demonstraram maior adaptabilidade, bom desenvolvimento corporal e melhor desempenho lactacional. As cabras Alpinas Americanas mostraram menores respostas adaptativas e produtivas o que evidencia a importância do ambiente térmico na criação desses animais. [Thermoregulatory traits and performance of dairy goats in early lactation in tropical weather]. Abstract: The objective of this study was to evaluate physiological and performance characteristics in early lactation of dairy goats of several breeds, namely thermoregulation, body condition and milk production. Forty five females were used (15 Saanen, 15 of crosses between undefined breed and _ Murciana and 15 American Alpine). Records were made of rectal temperature, respiratory rate, body condition score and daily milk production in the 36 first days of lactation. Plasma concentrations of triiodothyronine and thyroxine were obtained by radioimmunoassay method. The meteorological variables were registered at 15 pm, at the same time as the collection of physiological indicators. Results indicate that American Alpine goats had higher rectal temperatures and respiratory frequency, lower concentration of triiodothyronine and thyroxine, associated to a smaller milk production and body condition, possibly due to the worse climate adaptation. Saanen and _ Murciana crosses presented lower rectal temperatures and respiratory frequency, higher body score and triiodothyronine and thyroxine concentrations. Rectal temperatures were similar between the genetic groups undefined breed x _ Murciana and different for Saanen goats. In the initial third of lactation crossbred goats along with Saanen goats showed greater adaptability, good physical development and better milk production. The American Alpine goats showed less productive and adaptive responses which highlights the importance of the thermal environment in the management of these animals

    Locally adapted brazilian sheep: a model of adaptation to Semiarid region.

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    Abstract: Well adapted animals are characterized by maintain homeostasis under natural conditions. The present study aimed to evaluate physiological and morphological responses, as well as identify the relationship between these parameters in order to maintain homoeothermic status, in the dry and rainy season. Measurements were taken from 383 Morada Nova hair ewes, under dry and rainy season. The studied variables included rectal temperature (RT), respiratory rate (RR), coat thickness (CT), hair length (HL), hair diameter (HD) and hair density (D). Blood samples were collected for determining biochemical, erythrogam and hormone concentration. The evaluated blood parameters from the Morada Nova breed did not demonstrate any variation from the reference interval established for sheep, confirming its adaptability profile even under high radiation and air temperatures. Multivariate analyses were performed in order to determine relationship between morphological, biochemical, erythrocyte and hormonal traits in each season. Differences correlations were observed according to season of the year. In the dry season, the correlations were significant among RT, RR, Packed cell volume (PCV), thyroxine (T4), Glucose (GLU), CT, HL, Globulin (GLO) and Total Protein (TP), whereas in dry season the characteristics that showed greater correlation were Mean corpuscular volume (MCV), thyroid hormones, Creatinine, GLO, TP, PCV and GLU. In conclusion, Morada Nova ewes was able to maintain homeothermy, even in the most stressful environmental conditions. Their hematological, biochemical and hormonal profile were within the normal range for sheep, confirming the adaptability of this local breed to the Brazilian semiarid environment. [Ovelha brasileira localmente adaptada: um modelo de adaptação para o semiárido]. Resumo: Os animais bem adaptados são caracterizados por manter a homeostase em condições naturais. O presente estudo teve como objetivo avaliar as respostas fisiológicas e morfológicas, bem como identificar a relação entre esses parâmetros a fim de, manter o estado homeotérmico, na estação seca e chuvosa. As medições foram tomadas em 383 ovelhas da raça Morada Nova, na época seca e chuvosa. As variáveis estudadas incluíram temperatura retal (TR), frequência respiratória (FR), espessura do pelame (EP), comprimento do pelo (CP), diâmetro do pelo (D) e densidade numérica (DN). Foram coletadas amostras de sangue para determinar a concentração bioquímica, eritrogama e hormonal. Os parâmetros de sangue avaliados da raça Morada Nova não demonstraram variação do intervalo de referência estabelecido para ovinos, confirmando que seu perfil de adaptabilidade, mesmo sob alta radiação e temperaturas do ar. Foram realizadas análises multivariadas para determinar a relação entre características morfológicas, bioquímicas, eritrocitárias e hormonais em cada estação. As correlações de diferenças foram observadas de acordo com a estação do ano. Na estação seca, as correlações foram significativas entre TR, FR, PCV, T4, GLU, CT, HL, GLO e TP, enquanto que na estação seca as características que apresentaram maior correlação foram MCV, T4, T3, CRE, GLO, TP PCV e GLU. Em conclusão, as ovelhas Morada Nova conseguem manter a homeotermia, mesmo nas condições ambientais mais estressantes. Seu perfil hematológico, bioquímico e hormonal permanecem dentro da faixa de normalidade para ovinos, confirmando a adaptabilidade dessa raça local ao ambiente semiárido brasileiro

    P5A-Type ATPase Cta4p Is Essential for Ca2+ Transport in the Endoplasmic Reticulum of Schizosaccharomyces pombe

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    This study establishes the role of P5A-type Cta4 ATPase in Ca2+ sequestration in the endoplasmic reticulum by detecting an ATP-dependent, vanadate-sensitive and FCCP insensitive 45Ca2+-transport in fission yeast membranes isolated by cellular fractionation. Specifically, the Ca2+-ATPase transport activity was decreased in ER membranes isolated from cells lacking a cta4+ gene. Furthermore, a disruption of cta4+ resulted in 6-fold increase of intracellular Ca2+ levels, sensitivity towards accumulation of misfolded proteins in ER and ER stress, stimulation of the calcineurin phosphatase activity and vacuolar Ca2+ pumping. These data provide compelling biochemical evidence for a P5A-type Cta4 ATPase as an essential component of Ca2+ transport system and signaling network which regulate, in conjunction with calcineurin, the ER functionality in fission yeast
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