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排序方式: 共有458条查询结果,搜索用时 15 毫秒
61.
Juliana Aguiar Interaminense Nathalia Ferreira Calazans Bruna Critas do Valle Joana Lyra Vogeley Sílvio Peixoto Roberta Soares Jos Vitor Lima Filho 《Journal of the World Aquaculture Society》2014,45(1):65-74
Experiments were conducted to evaluate different prophylactic methods to control the bacterial load in brine shrimp, Artemia, hatching. The first experiment evaluated three treatments to control Vibrio spp. during the Artemia hatching: microalgae (Chaetoceros calcitrans), probiotic (Bacillus spp.), and antibiotic (Florfenicol). In the second experiment, Artemia metanauplius were enriched in distinct treatments with C. calcitrans, probiotic, and emulsion rich in docosahexaenoic and eicosapentaenoic fatty acids. Enriched Artemia metanauplius and nauplii (control) were offered to white shrimp, Litopenaeus vannamei, postlarvae (PL7–PL19). Presumptive Vibrio were quantified in Artemia, PL, and rearing water. Microalgae and probiotic were effective to control Vibrio spp. in Artemia nauplii. The enrichment process increased the Artemia bacterial load but did not affect Vibrio load in L. vannamei. 相似文献
62.
C. V. Soares Filho J. F. Cavazzana R. Heinrichs J. M. B. Vendramini G. C. Lima 《Communications in Soil Science and Plant Analysis》2018,49(3):358-370
The management of nitrogen (N) fertilization in pasture has great importance for yield and maintenance of Brazilian livestock. The objective of this study was to evaluate soil chemical attributes, shoot dry weight yield (SDWY) and roots dry weight yield (RDWY), nutritional status and nutritive value of Mulato II Urochloa grass that received organic biofertilizer rates as N source. The treatments were arranged in completely randomized blocks, were fertilized with six organic biofertilizer rates (0, 25, 50, 100, 200, and 400 m3 ha?1) and five replicates during four harvest cycles. There was a quadratic response in the accumulated SDWY for up to a rate of 400 m3 ha?1 and RDWY with 330 m3 ha?1 of organic biofertilizer. The organic biofertilizer influenced the soil chemical attributes and foliar nutrient concentration. However, only the crude protein content presented a quadratic response, and neutral detergent fiber and acid detergent fiber levels were not affected by the influence of organic biofertilizer applied to the soil. 相似文献
63.
Biofilms of Candida spp. from the ocular conjunctiva of horses with reduced azole susceptibility: a complicating factor for the treatment of keratomycosis? 下载免费PDF全文
Raimunda Sâmia Nogueira Brilhante Paula Vago Bittencourt Débora de Souza Collares Castelo‐Branco Glaucia Morgana de Melo Guedes Jonathas Sales de Oliveira Lucas Pereira Alencar Rossana de Aguiar Cordeiro Mariana Pinheiro Evilázio Fernandes Nogueira‐Filho Waldemiro de Aquino Pereira‐Neto José Júlio Costa Sidrim Marcos Fábio Gadelha Rocha 《Veterinary ophthalmology》2017,20(6):539-546
64.
J. S. Penha A. C. A. Lopes R. L. F. Gomes J. B. Pinheiro J. R. Assunção Filho E. A. Silvestre J. P. G. Viana J. Martínez-Castillo 《Genetic Resources and Crop Evolution》2017,64(6):1355-1364
Lima bean (Phaseolus lunatus L.) is an important food source in Brazil, especially in the northeast region, where its production and consumption are high. The goals of the present study were to estimate natural outcrossing rates and genetic diversity levels of Lima bean from Brazil, using ten microsatellite loci to obtain information for their conservation and breeding. Fourteen accessions were selected from an experiment in field with open-pollinated and with the presence of pollinating insects. Twelve seeds of each of the 14 selected accessions were grown in screenhouse for tissue harvest and DNA extraction. The multilocus model was used to determine the reproductive system. The outcrossing rate was 38.1 % (tm = 0.381; ts = 0.078), and the results indicated a mixed mating system with a predominance of selfing (1 ? tm = 61.9 %). The biparental inbreeding rate was high (t m ? t s = 0.303) and the multilocus correlated paternity was quite high (r p(m) = 0.889), indicating that the progeny was mostly composed of full sibs. The average effective number of pollen donors per maternal plant (N ep ) was low (1.12), and the fixation index for maternal genotypes (F m ) was 0.945, indicating that most genitors resulted from inbreeding. The studied families presented considerable genetic variability: A = 6.10; %P = 30; H e = 0.60 and H o = 0.077. Total diversity was high (H T = 0.596), and a portion was distributed within families (H S = 0.058). In addition, diversity was higher between families (D ST = 0.538), and genetic differentiation was high (G ST = 0.902). The results presented here can be used in the implementation of Lima bean conservation and breeding programs in Brazil. 相似文献
65.
Pharmacokinetics and pharmacodynamics of the injectable formulation of methadone hydrochloride and methadone in lipid nanocarriers administered orally to horses 下载免费PDF全文
N. Crosignani S. P. Luna T. Dalla Costa E. L. Pimenta C. B. Detoni S. S. Guterres J. N. Puoli Filho J. C. Pantoja M. C. Pigatto 《Journal of veterinary pharmacology and therapeutics》2017,40(4):398-405
We investigated the thermal, electrical and mechanical antinociceptive and physiological effects (heart rate, respiratory rate, arterial blood pressure, head height and abdominal auscultation score), and pharmacokinetics, of 0.5 mg/kg of the injectable formulation (ORAL) or nanoparticulated methadone (NANO) given orally, in six adult mares, using a crossover, blind and prospective design. Repeated‐measure models were used to compare parametric data between and within treatments, followed by Tukey's test. Nonparametric data were analysed with Wilcoxon signed‐rank, adjusted by Bonferroni tests. Blood samples were also collected up to 6 h after dosing for plasma drug quantification by LC‐MS/MS. Methadone pharmacokinetic parameters were determined by noncompartmental and compartmental approaches. There were no differences in pharmacodynamic parameters. No statistical differences were observed in the pharmacokinetic parameters from noncompartmental analysis for both groups, except a significant decrease in peak plasma concentration, increase in apparent volume of distribution per fraction absorbed (Vdss/F) and increased mean residence time (MRT) for NANO. One‐compartment open model with first order elimination best described the pharmacokinetic profiles for both groups. Neither ORAL nor NANO administered orally to horses produced antinociception. The nanoencapsulated formulation of methadone given orally to horses did not improve methadone pharmacokinetic parameters or increased systemic body exposure to methadone. 相似文献
66.
Janilson G. Rocha Laércio Zambolim Eunize M. Zambolim Francisco X. Ribeiro do Vale Waldir C.J. Junior Armando Bergamin Filho 《Crop Protection》2010
Coffee leaf scorch caused by Xylella fastidiosa is widespread in major coffee-growing regions of Brazil. This study was done to quantify the yield loss caused by this disease. The severity data of the disease were collected during the 2006, 2007 and 2008 seasons at commercial plantations growing Coffea arabica ‘Catuaí’ in São Gotardo-MG in 250 plants of three blocks of 7000 coffee plants each. Fifty selected plants per block with different disease severities were determined. The linear regression showed a significant relationship (P < 0.01) between disease severity and bean yield and between disease severity and grain size in all years. The relationship between yield and the disease severity was significant (P < 0.01). For each 1% increase in the disease severity, there was a decrease of 1.22, 1.34 and 2.02 bags of bean yield/ha in 2006, 2007 and 2008, respectively, thus showing the importance of the disease in reducing coffee bean yields. 相似文献
67.
Taciana P. Spinelli Edmilson F. Oliveira‐Filho Davi Silva Rinaldo Mota F. B. Sá 《Veterinary ophthalmology》2010,13(Z1):134-136
Objective To determine the normal aerobic bacterial conjunctival population of the Coatis and the Crab‐eating raccoons housed in captivity in the Pernambuco and Paraiba states of Brazil. Animals studied Ten healthy Coatis and 10 healthy Crab‐eating raccoons were selected for this study. Animals are from three zoos situated at the Pernambuco and Paraiba States in the north‐east of Brazil. Procedures After ophthalmologic examination, swabs from healthy animals were carefully collected in order to avoid contamination. Samples were identified and submitted to the laboratory. Swabs were plated for culture on ovine blood agar (8%) and agar Levine and incubated at 37 °C and observed 24 and 48 h. Results Staphylococcus spp. was the most common microorganism isolated from conjunctival sac. Shigella spp. comprised the Gram‐negative genera isolated. Escherichia coli were isolated from the right eye of one Coati that had no growth at contralateral eye. Nine eyes from coatis and 10 from Crab‐eating raccoons had no microorganisms isolated. Conclusion Our results were in accordance with previous studies indicating Staphylococcus sp., followed by Corynebacterium spp. as the most common inhabitant of the eyes of most mammalian species. 相似文献
68.
We assessed the response of maize canopy arthropods to the insecticide chlorpyrifos. Four 0.3 ha (18 2 180 m) plots were divided into two subplots, a control and a treated area. During tasseling of the plants, the treated area was sprayed twice, with an interval of 3 days. Ten plants were sampled: 1 day before spraying, and 7, 14, 21 and 28 days after spraying. The insecticide had no effect on insect herbivores: a high density of Spodoptera frugiperda larvae was present in the treated plots. A few predator arthropod species were negatively affected by the insecticide, but their numbers or activity increased 2 weeks after the treatment of the plots. A canonical variate analysis showed no pronounced effect of the insecticide on arthropod communities; the largest variations on species abundance were related to sampling occasion. These results can be explained by the combination of the short period of chlorpyrifos residual activity on the plant surface and the great potential for recolonization of the areas by most of the monitored arthropods. 相似文献
69.
70.
José Wilacildo de Matos Oliveiro Guerreiro-Filho Wallace Gon?alves Daniel Alves Ramiro Bárbhara Joana dos Reis Fatobene 《Euphytica》2011,181(2):253-260
The coffee leaf miner, Leucoptera coffeella, is the most important pest of Coffea arabica plantations in Brazil, and all cultivars are susceptible to the insect. However, distinct reactions have been observed in
other species, such as C. congensis and C. canephora. In this work, the occurrence of antixenotic response was surveyed in individuals of Coffea species, selected for resistance to the leaf miner at both field and laboratory conditions. Tests performed on young plants
from C. arabica cultivars Icatu Precoce IAC 3282, Mundo Novo IAC 515-20, Tupi IAC 1669-33 and Catuaí Amarelo IAC 62 demonstrated that these
were preferred for oviposition when pooled with seedlings from C. canephora cv. Apoat? IAC 2258. Apoat? was also preferred over C. racemosa for oviposition. Similar results were observed in tests using detached leaves, and higher amount of eggs was counted in the
cv Obat? IAC 1669-20 and Catuaí Vermelho IAC 81, and lower oviposition frequency was observed in C. canephora cv. Guarini IAC 1598. C. congensis showed an oviposition frequency between C. arabica and C. canephora. Also, the results suggest that the frequency of oviposition is co-related with the plant resistance level, during larvae
infection. 相似文献