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51.
Luis Delucchi Martín Fraga Karen Perelmuter Claudia Della Cella Pablo Zunino 《Canadian journal of veterinary research》2014,78(2):153-155
The objective of the present work was to determine the effect of Lactobacillus murinus strain LbP2 on canine fecal immunoglobulin A (IgA) levels. Seven dogs were orally treated with a 3-mL suspension of L. murinus LbP2 containing 5 × 109 colony-forming units on alternate days for 2 wk. Six dogs were treated with 3 mL of phosphate-buffered saline as placebo. Fecal samples were taken from the rectal ampulla on days 0 and 16, and the total canine fecal IgA concentration was determined with an immunoperoxidase assay kit. The IgA levels of individual dogs were compared with the nonparametric Wilcoxon test. Differences were considered significant when the P-value was less than 0.05. An increase in the total fecal IgA concentration was observed in the 7 dogs after treatment with L. murinus LbP2 (P = 0.01796). No differences were detected between the initial total fecal IgA values and those obtained at the end of placebo treatment. Thus, after oral administration L. murinus LbP2 showed potential immunomodulatory effects, an important property to assess in a microorganism being considered for use as a probiotic. 相似文献
52.
Effectiveness of a Full-Scale Constructed Wetland for the Removal of Metals from Domestic Wastewater
The mobility of fluorescein and bromide used as tracers in packed soil columns was investigated. Five different soils were used in two application methods: soil surface application and soil incorporation, both of which simulate accepted methods of soil application of termiticides to prevent structural infestation. The breakthrough of bromide and fluorescein in column eluates were measured. The absorbance of fluorescein at 492 nm was pH dependent, and proper adjustments were made after measuring the eluate pH. Although high recoveries of bromide from the soil columns were observed, the breakthrough was different among the soil types, indicating that bromide behaves differently in different soils. Recovery of fluorescein, a weak acid, varied depending upon the pH of the soil used, and was only observed in the eluates of two of the five soils tested. Soil treated with bromide and fluorescein followed by soaking extraction showed high recovery of bromide but low recovery of fluorescein, except for in the most alkaline of the soils tested. If fluorescein is used as a conservative tracer in pesticide soil mobility studies, mobility can be underestimated in acidic soils because the active ingredient might travel more quickly than does the fluorescein. 相似文献
53.
Rosa CA Ribeiro JM Fraga MJ Gatti M Cavaglieri LR Magnoli CE Dalcero AM Lopes CW 《Veterinary microbiology》2006,113(1-2):89-96
In Brazil, commercial feedstuffs are an important component in modern animal husbandry, but there is no information available about fungal contamination and ochratoxin A (OTA) production. The aims of this study were to determine the mycoflora incidence in poultry feeds and evaluate OTA production. In addition, the ability to produce OTA by several Aspergillus and Penicillium species was investigated. A total of 96 samples of poultry feeds were collected from four factories in Rio de Janeiro. Samples were examined for total moulds, for Aspergillus and Penicillium spp. occurrence and for their relative densities on dichloran rose bengal chloramphenicol and dichloran 18% glycerol media. The capacity to produce ochratoxin A by selected Aspergillus and Penicillium species was determined by HPLC. Total mould counts were generally higher than 1 x 10(5 )CFU ml(-1). Aspergillus and Penicillium species were isolated in the highest numbers. Aspergillus flovus and Penicillium citrinum were the most prevalent species. There was a high percentage of potential OTA producers (46%). The amount of OTA produced on this substrate was enough to cause adverse effects in animals. Several strains isolated from poultry feeds were able to produce high levels of OTA on chloramphenicol yeast medium. OTA in raw materials needs to be surveyed and storage practices must be investigated to determine occurrence and establish the livestock toxicological risk in poultry feed. 相似文献
54.
Josefa Susana Alvarez Alfredo Hernndez‐Llamas Jos Galindo Iliana Fraga Tsai García Humberto Villarreal 《Aquaculture Research》2007,38(7):689-695
The feasibility of substituting soybean meal for fishmeal diets for juvenile white shrimp Litopenaeus schmitti (0.35±0.01 g) was evaluated, and an adequate substitution level was determined. Five diets were evaluated using 46%, 59%, 75%, 88% and 100% substitution levels. Pellet water stability was significantly affected by dietary soybean content (P<0.05). Increased soybean content produced lower pellet stability, ranging from a dry matter loss of 14–22% after a 2‐h immersion, and 20–33% after an 8‐h immersion. After 52 days, significant differences (P<0.05) were found in shrimp weight, feed conversion ratio and protein efficiency ratio. The values were 0.64–1.06 g, 2.8–7.9 and 0.45–1.21, respectively, for the three measurements. Overall, better results were obtained with diets where soybean meal was substituted for fishmeal up to 75%. The 100% soybean meal diet resulted in poor growth performance of shrimp. Survival rates were acceptable for all treatments (90% or higher) and no significant differences were found in survival between treatments. Regression analysis using the broken‐line methodology indicated that 76.5±2% is an optimum soybean substitution level in diets that contained fishmeal and soybean as the major protein sources for grow‐out of juvenile white shrimp. 相似文献
55.
Pedro Gallardo Gemma Martínez Gabriela Palomino Adriana Paredes Gabriela Gaxiola Gerard Cuzon Ruth Pedroza‐Islas 《Journal of the World Aquaculture Society》2013,44(2):187-197
The effects of two microencapsulated feeds were evaluated on development, growth, survival, proteolytic activity, and biochemical composition of white shrimp, Litopenaeus vannamei, larvae. The treatments were: (1) basal microcapsules (BM), (2) microcapsules containing krill hydrolysate (BMK), and (3) live food control (LFC: Artemia franciscana nauplii) with all treatments receiving algae (Chaetoceros ceratosporum and Tetraselmis chuii). No significant differences were found in development index and survival among larvae. Growth rate was significantly higher in larvae fed LFC (15 ± 0.06%/d) as compared with those offered the BM diet (7.5 ± 0.5%/d) with the BMK (11 ± 0.04%/d) treatment producing intermediate results. The activity of total proteases and chymotrypsin decreased significantly after Mysis I (MI) in larvae fed LFC or BMK. Protein content of larvae increased significantly toward PL1. The acylglycerides content in MIII fed on LFC (2.3 ± 0.2%/dw) was higher than that MI fed BM (1 ± 0.01%/dw). No difference was observed in the cholesterol (CH) content of the larvae. The acylglycerides/protein and cholesterol/protein ratios showed a decreasing pattern between MI and PL1, indicating that these two ratios were related to ontogenetic shifts. These results demonstrate improvements in microparticulate diets when krill hydrolysates are included in the formulation. 相似文献
56.
Initial larval stocking density, prey density, daily prey ration and light conditions (light intensity and photoperiod) were tested for common dentex larval rearing under experimental conditions. Experiments continued until the first peak of larval mortality. The best results in larval survival were obtained with an initial stocking density of between 10 and 40 larvae L?1, fed with at least 10 rotifers mL?1, maintaining ratios of 500–1000 rotifers larva?1, with one or two adjustments of prey density per day. The use of more than 2000 rotifers larva?1 or three daily adjustments of live prey density had negative effects on larval survival. The best light conditions for common dentex larval rearing were found using a photoperiod of 24 h L:0 h D and an intensity of at least 3.4 μmol m?2 s?1. 相似文献
57.
Peña E Domínguez R Bermejo A Cocho JA Fraga JM Bermejo P 《Journal of agricultural and food chemistry》2004,52(15):4887-4892
The purpose of the present paper is to develop an easy and quick in vitro method to compare copper availability from breast milk and infant formulas. This study focuses on the differences caused by the use of pH 2.0 (adult gastric pH) or pH 5.0 (newborn gastric pH) in the first stage of the enzymolysis. pH affects Cu solubility, a possible estimator of the availability. Selection of a digestor, times of enzymolysis, centrifugation parameters, and Cu determination by ETAAS were discussed as well. Percentage of Cu solubility was larger from breast milk (gastric pH 2.0, 65.3 +/- 14.0 vs 40.0 +/- 13.9%; gastric pH 5.0, 61.2 +/- 16.5 vs 26.6 +/- 10.3%), but the soluble content was larger from infant formulas for both pHs (gastric pH 2.0, 245.3 +/- 82.1 vs 113.0 +/- 103.4 ng mL(-1); gastric pH 2.0, 169.3 +/- 76.9 vs 75.3 +/- 21.9 vs ng mL(-1)). 相似文献
58.
Effect of organic acids and nitrogen source on alcoholic fermentation: study of their buffering capacity 总被引:5,自引:0,他引:5
Torija MJ Beltran G Novo M Poblet M Rozès N Mas A Guillamón JM 《Journal of agricultural and food chemistry》2003,51(4):916-922
The effect of tartaric acid and other organic acids on alcoholic fermentation was studied. Organic acids in media with high sugar concentrations and ammonium as the sole nitrogen source had an enormous impact on Saccharomyces cerevisiae metabolism during alcoholic fermentation. The main effect on yeast metabolism was the quick acidification of the media in the absence of organic acids. All of the organic acids used in this study (tartaric, malic, citric, and succinic acids) showed a buffering capacity, but not all of the acids had the same one. However, the results suggested that buffering should not be considered the only effect of organic acids on yeast metabolism. Nitrogen source also had a great influence on media pH. Ammonium consumption by yeasts produced a greater acidification of the media than when amino acids were used. 相似文献
59.
Mourad Baghour Diego A Moreno Gemma Víllora Inmaculada López-Cantarero Joaquín Hernández Nicolas Castilla Luis Romero 《Journal of agricultural and food chemistry》2002,50(1):140-146
Root-zone temperatures (RZT) in relation to Cu and Zn uptake and tissue accumulation, and to total biomass, in potato plants (Solanum tuberosum L. var. Spunta) were studied. Using five different plastic mulches (no cover, transparent polyethylene, white polyethylene, coextruded white-black polyethylene, and black polyethylene) resulted in significantly different RZT (16, 20, 23, 27, and 30 degrees C, respectively). These RZT significantly influenced Cu and Zn content (concentrated) and the biomass in various potato organs. Root-zone temperature at 20 degrees C resulted in significantly high Cu content in leaflets, and soluble Cu content in leaflets and stems, whereas 23 and 27 degrees C resulted in significantly high Cu content in roots. However, RZT had no effect on Cu content in tubers or stems or on soluble Cu in roots or tubers. The RZT at 20 degrees C resulted in significantly high Zn and soluble Zn in stems, roots, and tubers; whereas, at 27 degrees C Zn and soluble Zn content were significantly highest in leaflets. The most biomass occurred in roots and tubers at 27 degrees C; whereas in leaves and stems, the RZT influence was highly variable. Total accumulation of both Cu forms was affected by RZT at 20 degrees C, with roots and tubers having significantly the least Cu and stems and leaflets having the most. Total accumulation of both Zn forms by RZT in potato organs was highly variable, but tubers consistently accumulated the most. 相似文献
60.
Hidalgo FJ Gómez G Navarro JL Zamora R 《Journal of agricultural and food chemistry》2002,50(21):5825-5831
(13)C NMR spectra of oil fractions obtained chromatographically from 66 vegetable oils were obtained and analyzed to evaluate the potential use of those fractions in predicting oil stabilities and to compare those results with oil stability prediction by using chemical determinations. The oils included the following: virgin olive oils from different cultivars and regions of Europe and north Africa; "lampante" olive, refined olive, refined olive pomace, low-erucic rapeseed, high-oleic sunflower, corn, grapeseed, soybean, and sunflower oils. Oils were analyzed for fatty acid and triacylglycerol composition, as well as for phenol and tocopherol contents. By using stepwise linear regression analysis (SLRA), the chemical determinations and the (13)C NMR data that better explained the oil stability determined by the Rancimat were selected. These selected variables were related to both the susceptibility of the oil to be oxidized and the content of minor components that most contributed to oil stability. Because (13)C NMR considered many more variables than those determined by chemical analysis, the predicted stabilities calculated by using NMR data were always better than those obtained by using chemical determinations. All these results suggest that (13)C NMR may be a powerful tool to predict oil stabilities when applied to chromatographically enriched oil fractions. 相似文献