840 resultados para Production territory and local development


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Heat stress has negative effects on bovine reproduction, particularly for European breeds (Bos taurus taurus) that are less thermotolerant than zebu cattle (Bos taurus indicus). Here, the evidence that spermatozoa and oocyte both contribute to early embryonic resistance to heat shock is demonstrated. In addition, the use of reproductive biotechnologies to improve bovine thermotolerance, are outlined by comparing data from taurus, indicus and crossbred genotypes. (c) 2005 Published by Elsevier B.V.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Three experiments were carried out to analyze the performance and egg quality of Japanese quails throughout the day when submitted to different lighting programs. In each experiment, birds were submitted to a period of 28 days for adaptation to the lighting program. During the following three days, each day - from 7 am to 7 pm or 9 pm - was divided into six or seven periods of two hours each, and the remaining hours corresponded to another single period. All birds were submitted to the same management practices, and received water and feed ad libitum. The experimental diet was formulated according to NRC (1994) standards. It was observed lower feed intake in the period of 9 pm to 7 am, and a higher incidence of lay from 3 pm to 7 pm, as opposite to hens, which peak of egg laying occurs during the morning. Some controversial results were found among experiments as to eggshell quality during the different periods of the day. Variation on the lighting program had little influence on the other performance and egg quality parameters.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Mammalian oocytes can undergo spontaneous meiotic maturation when they are liberated from their follicles and cultured in vitro; however, the zona pellucida (ZP) becomes resistant to chymotrypsin digestion, or hardens, when spontaneous maturation occurs in serum-free medium. Schroeder et al. [Biol. Reprod. 43 (1990) 891] described that fetuin, a component of fetal calf serum (FCS), inhibits ZP hardening during oocyte maturation. The aim of this experiment was to study the effect of the presence of cumulus cells and addition of hormones to maturation media on bovine zona hardening and embryo development in medium with and without fetuin. In Experiment 1, different concentrations of fetuin were added to the maturation medium. The time necessary for digestion of 50% of the ZP (d50) was not different when oocytes were matured in presence of 10% FCS, 1 mg/ml polyvinyl alcohol (PVA), or 4, 1 and 0.25 mg/ml of fetuin; cleavage rates were also similar. However, significantly more blastocysts (P < 0.05) were formed when FCS was used compared to PVA and 0.25 mg/ml of fetuin. In Experiment 11, we examined the influence of the presence of cumulus cells and hormones during the maturation of oocytes in media with PVA, BSA, FCS and fetuin. The d50 was significantly higher (P < 0.05) when oocytes were matured in presence of cumulus cells. The cleavage rate of cumulus-intact oocytes was similar for all groups. However, when oocytes were partially stripped before maturation, the cleavage rate was significantly higher (P < 0.05) when FCS or fetuin was used. In both stripped and non-stripped groups, significantly more blastocysts (P < 0.05) were formed when oocytes were matured with FCS compared to BSA and PVA. These results indicate that zona hardening, as described for mouse and human oocytes, does not have a large effect on bovine cumulus-intact oocytes. Apparently fetuin can be used as a substitute for FCS during bovine oocyte maturation, since it leads to similar developmental rates as FCS in intact and partially stripped oocytes. (C) 2002 Published by Elsevier B.V. B.V.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

O setor de floricultura movimenta cerca de um bilhão de dólares no Brasil e o desenvolvimento de técnicas direcionadas ao controle do florescimento é necessário. O presente trabalho avaliou a influência do ácido giberélico (GA3) no desenvolvimento vegetativo e reprodutivo de plantas jovens de Phalaenopsis FSNT 'Dai-Itigo', híbrido de coloração rósea. A aplicação do GA3 foi feita via pulverização foliar nas concentrações de 0, 125, 250, 500 e 1.000 mg L -1. O comprimento das folhas aumentou consideravelmente com o uso do GA3 em baixas concentrações, porém houve diminuição da largura foliar das plantas tratadas com esse fitorregulador. A aplicação do GA3 na concentração de 125 mg L -1 apresentou os melhores resultados para a promoção do florescimento e qualidade da floração deste híbrido de orquídea. Nesse tratamento, aproximadamente 50% das plantas pulverizadas apresentaram floração cerca de 6-12 meses antes da floração das plantas sem aplicação do fitorregulador. em conclusão, a qualidade da floração e das flores foi melhor no tratamento com 125 mg L -1 de GA3.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Megalopae were reared in the laboratory to the 7(th) crab stage. The megalopa and 1(st) crab stage are described and juvenile development was studied with emphasis on pleopodal differentiation. The megalopal phase, is easily identified, and shares with those of other Grapsinae and Plagusiinae big size, the presence of many natatory setae, and a series of conspicuous teeth on the inner margin of the dactyli from the 2(nd) to 4(th) walking leg. These features are regarded as adaptive for settlement in a wave-swept environment, such as the rocky marine intertidal where most of those species live. Fast development of juvenile pleopods is another characteristic of these subfamilies. In Pachygrapsus transversus, the sexes can be distinguished from the 2(nd) crab stage. Gonopod differentiation in males and the basic segmentation of all four pleopod pairs in females are already concluded at the 5(th) instar. A review of the available information indicated that settlement of large megalopae and fast juvenile development, preceding a precocious sexual maturity, are trends in Grapsinae and Plagusiinae. on the other hand, the Sesarminae pass through a more extensive juvenile instar sequence and presumably a delayed maturity.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

beta-Glucosidase and beta-xylosidase production by a yeastlike Aureobasidium sp. was carried out during solid-state and submerged fermentation using different carbon sources and crude enzymes were characterized. beta-Glucosidase and beta-xylosidase exhibited optimum activities at pH 2.0-2.5 and 3.0, respectively. These enzymes had the maximum activities at 65degreesC and were stable in a wide pH range and at high temperatures.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A strain of Aspergillus versicolor produces a xylanolytic complex containing two components, the minor component being designated xylanase II. The highest production of xylanase II was observed in cultures grown for 5 days in 1% wheat bran as carbon source, at pH 6.5. Xylanase II was purified 28-fold by DEAE-Sephadex and HPLC GF-5 10 gel filtration. Xylanase II was a monomeric glycoprotein, exhibiting a molecular mass of 32 kDa with 14.1% of carbohydrate content. Optimal pH and temperature values for the enzyme activity were about 6.0-7.0 and 55 degreesC, respectively. Xylanase II thermoinactivation at 50degreesC showed a biphasic curve. The ions Hg2+, Cu2+ and the detergent SDS were strong inhibitors, while Mn2+ ions and dithiothreitol were stimulators of the enzyme activity. The enzyme was specific for xylans, showing higher specific activity on birchwood xylan. The Michaelis-Menten constant (K-m) for birchwood xylan was estimated to be 2.3 mg ml(-1) while maximal velocity (V-max) was 233.1 mumol mg(-1) min(-1) of protein. The hydrolysis of oat spell xylan released only xylooligosaccharides. Published by Elsevier Ltd.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Bromeliaceae possess several features of pollen and anther wall development that are plesiomorphic for Poales, consistent with their putatively basal or near-basal placement in this order. For example, successive microsporogenesis and the monocotyledonous type of anther wall formation are both plesiomorphic features that occur commonly in other Poales, with a few notable exceptions, notably the simultaneous type of microsporogenesis in Rapateaceae. The intermediate type of tapetum development in Bromeliaceae was probably derived secondarily from a secretory type, which occurs in most other Poales except Typhaceae.