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791.
Pollyanna de Moraes França Ferreira Suellen Silva Condessa Juliana Silva Rocha Débora Werneck Caldas Juliana Rodrigues Gomes Maria Tatiana Soares Alex Junio Silva Cardoso Jener Alexandre Sampaio Zuanon 《Aquaculture Research》2017,48(9):4623-4631
With this study, we aimed to assess the safety of using Curcuma longa in fish feed. Juvenile Astyanax aff. bimaculatus (0.83 ± 0.04 g) were kept in 24 80‐L aquaria, at a density of 0.5 fish L?1 for 60 days. Six diets supplemented with 0.0, 20.0, 40.0, 60.0, 80.0 and 100.0 g kg?1 were evaluated. Histopathological analysis of the gills showed that there was an increasing linear effect of turmeric on the frequency of lamellar aneurysm, hypertrophy of mucous cells, oedema and necrosis. There was a quadratic effect of turmeric supplementation on the frequency of fusion and disruption of secondary lamellae, vacuolation and hypertrophy of the epithelial cells, and the estimated values to minimize these variables were 4.63, 25.93 and 24.46 g kg?1 respectively. There was a quadratic effect of turmeric on the gills index (IBRA), and the estimated value to minimize this index was 30.23 g kg?1. No effect of turmeric on the frequency of histopathological changes and organ index in fish liver was observed. Thus, we conclude that turmeric is not hepatotoxic for A. aff. bimaculatus; however, its use is safe at concentrations up to 30.23 g kg?1 diet as a function of its gill toxic effect at higher doses. 相似文献
792.
Rafael Ferreira Barreto Flávio José Rodrigues Cruz Lucas Aparecido Gaion Renato de Mello Prado Rogério Falleiros Carvalho 《植物养料与土壤学杂志》2018,181(3):382-387
The tomato (Solanum lycopersicum L.) cultivar Micro‐Tom (MT) is widely used in physiological studies, but the effects of nitrate ( ) and ammonium ( ) ratios ( : ratios) and, in particular, the effects of the accompanying ions in sources are unknown. To determine whether the accompanying ions in sources influence toxicity, the effects of : ratios on the physiology, electrolyte leakage index, nutrition, and dry weight were studied using hydroponics. The sources were ammonium chloride (NH4Cl) or ammonium sulfate [(NH4)2SO4], and five : ratios were used: 100 : 0, 75 : 25, 50 : 50, 25 : 75, and 0 : 100. The source was calcium nitrate [Ca(NO3)2], and the nitrogen (N) concentration was 15 mmol L?1. The results indicate that NH4Cl or (NH4)2SO4 can be used in studies on toxicity because the accompanying ions did not influence the tomato plants. In addition, : ratios of 100 : 0 and 75 : 25 resulted in the highest dry weight of tomato plants, whereas ratios of 25 : 75 or 0 : 100 were toxic. 相似文献
793.
Efficiency of microbial phytase supplementation in diets formulated with different calcium:phosphorus ratios,supplied to broilers from 22 to 33 days old 下载免费PDF全文
L. de P. Naves P. B. Rodrigues L. do V. Teixeira E. C. de Oliveira M. M. Saldanha R. R. Alvarenga A. D. Corrêa R. R. Lima 《Journal of animal physiology and animal nutrition》2015,99(1):139-149
An experiment was conducted with broilers from 22 to 33 days of age to evaluate the efficiency of six microbial phytases supplemented in diets (1500 FTU/kg) that were formulated with three different calcium:available phosphorus (Ca:Pavail) ratios (4.5:1.0, 6.0:1.0 and 7.5:1.0). A positive control diet without phytase was formulated with a Ca:Pavail ratio of 7.5:3.4 to meet the nutritional requirements of the broilers. The P and ash contents of the tibia, magnesium in the plasma, performance, balance and retention of phytate phosphorus (Pphyt), intake of total P and nitrogen (N), nitrogen‐corrected apparent metabolizable energy and apparent digestibility of dry matter of the diets were not influenced (p > 0.05) by the type of phytase or the dietary Ca:Pavail ratio. However, there was an interaction (p < 0.05) between the phytase type and the Ca:Pavail ratio for the retention coefficients of total P, Ca and N. Phytase B resulted in the highest Ca deposition in the tibia (p < 0.01). Phytases D, E and F reduced the Ca concentrations in the tibia (p < 0.01) and plasma (p < 0.05). Phytase D increased the P level in the plasma and decreased the total P excretion (p < 0.01). Phytases E and F increased Ca excretion, while phytase A reduced it (p < 0.01). Regardless of the phytase type, increasing the dietary Ca:Pavail ratio reduced (p < 0.05) the plasma P concentration and the excretion of total P and N and, conversely, increased (p < 0.05) the plasma concentration, intake and excretion of Ca. For the rearing period evaluated, it is possible to reduce the Pavail of the diet to 1.0 g/kg when Ca is maintained at 7.5 g/kg, and the diet is supplemented with 1500 FTU of phytase A, C, D or E/kg. This diet allows the maintenance of performance and adequate bone mineralization, and it improves the Ca, total P and Pphyt utilization in addition to reducing the excretion of N and P into the environment. 相似文献
794.
Rodrigues MR Caramão EB Arce L Ríos A Valcárcel M 《Journal of agricultural and food chemistry》2002,50(15):4215-4220
Micellar electrokinetic capillary chromatography was used to determine the essential oils obtained by steam distillation of different samples of marjoram (Majorana hortensis Moench) dried leaves and flowers. The electrophoretic method consisted of a running buffer of 10 mM NaH2PO4, 6 mM Na2B4O7, 50 mM SDS, 7 mM gamma-cyclodextrin, and 10% acetonitrile, adjusted to pH 8.0 by the addition of 0.1 M H3PO4. The following monoterpene hydrocarbons and alcohol compounds were extracted from real samples and determined by the method proposed: alpha-pinene, gamma-terpinene, alpha-terpinene, terpinolene, p-cymene, linalool, alpha-terpineol, and terpinen-4-ol. The most prominent component of dried leaves, flowers, and commercial samples was terpinen-4-ol in four of the samples analyzed; only in one sample was alpha-terpineol present as the major compound. 相似文献