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501.
Root development in agronomically distinct six‐rowed barley (Hordeum vulgare) cultivars inoculated with Azospirillum brasilense Sp7 下载免费PDF全文
Sarah B. Lade Carla Román Ana I. Cueto‐Ginzo Laura Maneiro Pilar Muñoz Vicente Medina 《Plant Breeding》2018,137(3):338-345
The growth‐promoting rhizobacteria Azospirillum brasilense Sp7 positively affects many crops, but its influence on barley remains to be fully investigated. The aim of this study was to track early root growth of four barley cultivars that are widely used in Spanish breeding programmes under different growing scenarios. Different growth conditions are hypothesized to affect the response of young plants to A. brasilense Sp7, so seeds were inoculated with A. brasilense Sp7 and directly sown in the growth chamber, or planted in vitro. Plant height was measured and root structure analysed with the WinRHIZO program. Azospirillum brasilense Sp7 inoculation increased the length, surface area and number of root tips in both systems and in most cultivars in a similar way. Cultivars ‘Barberousse’ and ‘Plaisant’ were the most responsive to A. brasilense Sp7 treatment, while ‘Albacete’ was especially interesting in terms of its physiological interaction with A. brasilense Sp7 under abiotic stress imposed by the in vitro system. The utility of the in vitro system is criticized. 相似文献
502.
Rafael de Paula Xavier de Andrade Marcelo de Andrade Ferreira Stela Antas Urbano Marcílio de Azevedo Sabrina Carla Rodrigues Félix Michelle Christina Bernardo de Siqueira Felipe José Lins Alves Juana Catarina Cariri Chagas 《Tropical animal health and production》2013,45(5):1191-1196
The objective of this study was to evaluate the effect of replacing Tifton 85 hay (0, 33, 66, or 100 %) with by castor bean hulls on the intake and nutrient digestibility and performance of 28 noncastrated lambs, averaging 7 months in age, 19.5?±?2.0 kg average live weight, fed on diets based on forage cactus. The animals were housed in individual pens for 100 days. The digestibility trial occurred 40 days after the start of the performance using LIPE® as an external indicator for estimating fecal dry matter production. The replacement of hay with Castor beans hulls linearly decreased the intakes of dry matter, neutral detergent fiber, organic matter, and crude protein and reduced the digestibility coefficients of the dry matter, neutral detergent fiber, organic matter content, crude protein, and total digestible nutrient content. The hot carcass and true carcass yields were not influenced by the treatments and the feed conversion increased linearly. The empty body weight, live weight at slaughter, hot and cold carcass weights, total gain, and average daily gain decreased linearly with the replacement. The replacement of Tifton 85 hay with castor bean hulls reduced the intake of dry matter, crude protein and energy, consequently reducing the performance of the animals. However, as the regression coefficients were of low magnitude, data were subjected to analysis of variance and means were compared using the Dunnett test with diet without castor bean hulls set as the control treatment. The Tifton 85 hay can be replaced up to 66 % by castor bean hulls in finishing diets for lambs. 相似文献
503.
Ana Margarida Henriques Teresa Fagulha Silvia Carla Barros Fernanda Ramos Margarida Dias Duarte Tiago Luís Paulo Carvalho Paula Mendonça Madalena Monteiro Hélder Craveiro Miguel Fevereiro 《Journal of Exotic Pet Medicine》2018,27(1):4-10
Aves polyomavirus 1 (APyV) is the causative agent of acute disease in birds and causes high mortality rates in nestlings. Infections have been reported worldwide in a significant number of caged bird species, such as parrots, caiques, budgerigars, lovebirds, and macaws. However, the number of complete viral sequences available in public databases is scarce, especially those with associated clinical histories. In this study, the clinical, pathological, epidemiological, and molecular characteristics of 2 APyV strains detected in Portugal are described. In the autumn of 2015, a 2-month-old female green-winged macaw (Ara chloroptera) from a small breeder died with signs of dehydration, weight loss, and depression, raising the suspicion of polyomavirus infection. Histopathological analysis revealed lesions compatible with APyV infection, and the presence of polyomavirus in several organs was confirmed by polymerase chain reaction. From the cohabitants tested (n = 14), 1 eclectus parrot (Eclectus roratus), which was more than 1-year-old, was also APyV DNA-positive. The full genomic sequences of the 2 strains were obtained and found identical, suggesting a single introduction in the premises and the occurrence of subsequent infections by the same virus. When compared with sequences of other APyVs available in public databases, high nucleotide similarity percentages were obtained, confirming the close genetic relationship among polyomaviruses worldwide. Interestingly, strain APV7, detected in a white-bellied parrot in 2008 in Japan, was the closest strain to those isolated in this report. Attempts to isolate the virus in eggs and cell lines failed. Phylogenetic analysis was performed by the Bayesian method to determine the phylogenetic classification of the macaw and parrot strains. Both clustered into group V, together with other strains from different bird species with no host or spatial-temporal relationships being observed. 相似文献
504.
Teresa De Pilli Roma Giuliani Barbara F. Carbone Antonio Derossi Carla Severini 《Cereal Chemistry》2005,82(5):494-498
Doughs made from wheat and almond flours, water, and five types of emulsifiers commonly used in confectionary and bakery products (soy lecithin, sucrose esters, mono‐glycerides, mono‐ and di‐glycerides of fatty acids, and diacetyl tartaric acid esters of monoglycerides [DATEM]) were studied. To evaluate the additive ability to retain the fatty fraction during the extrusion process, electrical conductivity was measured and fat loss (%) that occurs during extrusion processing was determined. The electrical conductivity measurements showed that the lower and better concentration of soy lecithin and mixed mono‐ and di‐glycerides of fatty acids to obtain an oil‐water emulsion was 0.2 g/100 g of dough, while for sucrose esters and mono‐glycerides of fatty acids, it was 0.7 g/100 g of dough. No efficacy for DATEM was observed. The fat loss results showed that sucrose esters were the most suitable emulsifiers for retaining the fatty fraction during extrusion processing, even at a very low amounts (2 g/kg of dough). 相似文献