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691.
Escobedo-García Sarai Salas-Tovar Jesús A. Flores-Gallegos Adriana C. Contreras-Esquivel Juan C. González-Montemayor Ángela M. López Mercedes G. Rodríguez-Herrera Raúl 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):96-102
Plant Foods for Human Nutrition - Agave bagasse is a fibrous-like material obtained during aguamiel extraction, which is also in contact with indigenous microbiota of agave plant during aguamiel... 相似文献
692.
Nitish Kunte Erin McGraw Sydney Bell David Held Luz‐Adriana Avila 《Pest management science》2020,76(1):26-41
RNA interference is a phenomenon in which the introduction of double‐stranded RNA (dsRNA) into cells triggers the degradation of the complementary messenger RNA in a sequence‐specific manner. Suppressing expression of vital genes could lead to insect death, therefore this technology has been considered as a potential strategy for insect pest control. There are three main routes of dsRNA administration into insects: (i) injections to the hemolymph, (ii) topical, and (iii) feeding. In this review, we focus on dsRNA administration through feeding. We summarize novel strategies that have been developed to improve the efficacy of this method, such as the use of nano‐based formulations, engineered microorganisms, and transgenic plants. We also expose the hurdles that have to be overcome in order to use this technique as a reliable pest management method. © 2019 Society of Chemical Industry 相似文献
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Autochthonous probiotic Lactobacillus sp. in the diet of bullfrog tadpoles Lithobates catesbeianus improves weight gain,feed conversion and gut microbiota
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S.A. Pereira G.T. Jerônimo N. da Costa Marchiori H.M. de Oliveira M.S. Owatari G.F.A. Jesus P. Garcia F. do Nascimento Vieira M.L. Martins J.L.P. Mouriño 《Aquaculture Nutrition》2017,23(5):910-916
Dietary supplementation with probiotics in animal production is an alternative to antibiotics. In frog culture, studies involving native strains of probiotic bacteria and their effects on the performance and intestinal histology of farmed animals are scarce. Therefore, this study aimed to evaluate a diet supplemented with Lactobacillus sp. in tadpoles of Lithobates catesbeianus. This randomized test was performed with two dietary treatments: non‐supplemented control diet and diet supplemented with Lactobacillus sp., with nine replications. The growth performance of Lactobacillus sp., including its bacterial enzymatic activity and stability in feed, as well as colonization and histology of the intestinal tract, was evaluated after 42 days of experimentation. Animals fed with a supplemented diet showed higher weight gain and concentration of lactic acid bacteria in the gut and lower feed conversion. No significant difference was observed in survival, total heterotrophic bacterial count or histological change in the gut between the two treatments. The Lactobacillus sp. strain was able to colonize the intestinal tract and feed and remain at a high concentration of 107 and 106 CFU g?1, respectively. It produced several enzymes, which might have contributed to the greater weight gain and lower feed conversion in the supplemented animals, thus demonstrating its probiotic potential for use as a dietary supplement in bullfrog tadpoles. 相似文献
695.
Marsili NR Lista A Fernandez Band BS Goicoechea HC Olivieri AC 《Journal of agricultural and food chemistry》2004,52(9):2479-2484
Two widely employed antimicrobials, benzoic and sorbic acids, were simultaneously determined in commercial orange juices employing a combination of a flow injection system with pH gradient generation, diode array spectrophotometric detection, and chemometric processing of the recorded second-order data. Parallel factor analysis and multivariate curve resolution-alternating least-squares were used for obtaining the spectral profiles of sample components and concentration profiles as a function of pH, including provisions for managing rank-deficient data sets. An appropriately designed calibration with a nine-sample set of binary mixtures of standards, coupled to the use of the second-order advantage offered by the applied chemometric techniques, allowed quantitation of the analytes in synthetic test samples and also in commercial orange juices, even in the presence of unmodeled interferents (with relative prediction errors of 8.7% for benzoic acid and 2.5% for sorbic acid). No prior separation or sample pretreatment steps were required. The comparison of results concerning commercial samples with a laborious reference technique yielded satisfactory statistical indicators (recoveries were 99.0% for benzoic acid and 101.4% for sorbic acid). 相似文献
696.
Rubens Ribeiro Silva Alvaro José Gomes Faria Adriana Augusta Neto Tayna Alves Pereira Jaci De Souza Dias Antônio Carlos Martins Santos 《Communications in Soil Science and Plant Analysis》2019,50(10):1267-1277
The aim of this work was to evaluate the effect of phosphorus (P) levels on nodulation and soybean production components in Cerrado soils. The experimental design was randomized in blocks, with five replicates, and four consecutive crop seasons (2013/2014, 2014/2015, 2015/2016, and 2016/2017), being cultivated in the same experimental field area. In the first three crop seasons phosphate fertilization were carried out establishing the treatments of increasing levels of P: 0, 43.6, 87.3, 131.0, and 174.6 kg ha?1, and an additional level (farm standard) of 42 kg ha?1. The results of this work refer to the crop season 2016/2017 without different P application, evaluating the influence of content of previous crop seasons. The dry weight of roots, plant population, thousand grains weight, grain yield, nitrogen (N) and P content in leaves, number and dry weight of nodules were evaluated in the reproductive stages (R2 and R8) of soybean. Increasing levels of P in soil provided significant effects on nodulation, morphological components and production of soybean plants. Levels above 40 mg dm?3 of P available in soil provided a reduction in the number and dry weight of the nodules that are highly correlated to reduction on grain yield. 相似文献
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698.
Esmeralda Chamorro Legarda Mateus Aranha Martins Patriula Kaliana Moreira Pereira Ramon Felipe Siqueira Carneiro Isabela Claudiana Pinheiro Walter Quadros Seiffert Claudia Machado Marco Antonio de Lorenzo Felipe do Nascimento Vieira 《Aquaculture Research》2020,51(9):3571-3581
This work compared the effects of different densities of Mugil curema integrated in the rearing of Litopenaeus vannamei in a biofloc system on the yield and ecological performance of the system. For that, an experiment lasting 55 days was conducted. Four groups were evaluated as follows: (a) T0: shrimp reared without mullet, (b) T10: shrimp reared with 22 fish per tank, (c) T20: shrimp reared with 43 fish per tank, and (d) T30: shrimp reared with 65 fish per tank, each treatment with four replicates. The sludge:biomass ratio was higher in the T0 treatment, while the T10–T20 treatments were more efficient, producing more biomass and less sludge. The use of water was 17% more efficient in all treatments with mullet. Mullet survival was higher in the T10 and T20 treatments (mean: 84 ± 8%) than in the T30 (61 ± 5%) treatment. The fish final biomass and yield limits of the system were 0.37 kg and 3.7 kg/m3 respectively. Finally, there was no increase in the total nitrogen output of the system up to the T10 density. In conclusion, it is possible to integrate mullet up to 3.7 kg/m3, increasing the yield in 20% and decreasing water use. 相似文献
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