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1.
Production of common bean(Phaseolus vulgaris)is limited by the occurrence of damping off(rhizoctoniosis),which is caused by the fungus Rhizoctonia solani.However,the co-inoculation of plant growth-promoting rhizobacteria(PGPR)involved in biological control along with diatomic nitrogen(N2)-fixing rhizobia can enhance N nutrition and increase production.In this context,finding microorganisms with synergistic effects that perform these two roles is of fundamental importance to ensure adequate yield levels.The aim of this study was to evaluate the effects of co-inoculation of nodule endophytic strains of the genera Bacillus,Paenibacillus,Burkholderia,and Pseudomonas with Rhizobium tropici CIAT 899,an N2-fixing rhizobial strain,on the biocontrol of damping off and growth promotion in common bean plants.Greenhouse experiments were conducted under axenic conditions using the common bean cultivar Pérola.The first experiment evaluated the potential of the 14 rhizobacterial strains,which were inoculated alone or in combination with CIAT 899,for the control of R.solani.The second experiment evaluated the ability of these 14 rhizobacterial strains to promote plant growth with three manners of N supply:co-inoculation with CIAT 899 at low mineral N supply(5.25 mg N mL^-1),low mineral N supply(5.25 mg N mL^-1),and high mineral N supply(52.5 mg N mL^-1).The use of rhizobacteria combined with rhizobia contributed in a synergistic manner to the promotion of growth and the control of damping off in the common bean.Co-inoculation of the strains UFLA 02-281/03-18(Pseudomonas sp.),UFLA 02-286(Bacillus sp.),and UFLA 04-227(Burkholderia fungorum)together with CIAT 899 effectively controlled damping off.For the common bean,mineral N supply can be replaced by the co-inoculation of CIAT 899 with plant growth-promoting strains UFLA 02-281/02-286/02-290/02-293.Nodule endophytes UFLA02-281/02-286 are promising for co-inoculation with CIAT 899 in the common bean,promoting synergy with rhizobial inoculation and protection against disease.  相似文献   
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Polymorphonuclear proteolytic activity and milk composition change   总被引:3,自引:0,他引:3  
Relationships between Quarter Milk Cell Count (QMCC) and Tank Milk Cell Count (TMCC) with milk biochemical and technological parameters in milk and dairy products were investigated. All parameters measured were affected by the increase of TMCC and QMCC between 0 and 600 000 cells/mL. The variable effect of lactation stage which is different for different authors, is discussed. The three mechanisms, measured during the inflammation of the udder, implicated in the modification of milk quality are described (a decrease in synthesis, a decrease in the milk barrier permeability and an increase in proteolytic activities). The direct effect of plasmin in caseinolysis is well known; the specific role of the increase of somatic cells (especially PMN) in the modification of milk quality is described. Several specific proteolytic activities of PMN are described and the impact of these activities on caseinolysis is evaluated. Two hypothetical mechanisms of caseinolysis by PMN are suggested and a synthetic scheme of the role of plasmin, bacteria and somatic cells in caseinolysis is discussed.  相似文献   
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OBJECTIVE: To evaluate the safety of an orally administered ivermectin and praziquantel paste with regard to variables associated with clinical findings, parturition, lactation, maternal care, and neonate viability in pregnant mares. ANIMALS: 40 pregnant mares. PROCEDURE: Mares were randomly allocated into treatment (n = 20) and control (20) groups and administered a placebo or 3 times the therapeutic dosage of ivermectin (0.6 mg/kg) and praziquantel (4.5 mg/kg) at 14-day intervals until parturition. Physical examinations were performed on mares and their foals after parturition (on postpartum days 30, 60, and 90) to identify any drug-related effects. As an aid in assessing general health, hematologic and serum biochemical analyses were performed monthly on the mares. RESULTS: In blood constituents, minor alterations that were not biologically important were observed. Reproductive performance was not affected by the unusual treatment duration or high dosage, although the drugs were administered during a crucial period of equine embryonic development (30 to 60 days). Neither adverse effects on mares nor abortions occurred. Follow-up evaluations of the foals for a 3-month period did not detect any abnormalities. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of the ivermectin-praziquantel paste appears to be safe in pregnant mares and their foals.  相似文献   
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ABSTRACT

Organic amendments in the soil perform better than synthetic fertilizers in regards to soil fertility and sustainable crop productivity. Experiments were conducted to compare the effects of organic and synthetic fertilizers on soil fertility and wheat (Triticum aestivum L.) productivity. Soil fertility and protein contents of wheat grains (13.2% and 13.3% during 2005–06 and 2006–07, respectively) were improved by organic amendments. However, synthetic fertilizer (at the rate of 150, 100, and 60 kg ha?1 N, P2O5, and K2O, respectively) applications resulted in the maximum grain yield (4.05 and 4.46 t ha?1 during 2005–06 and 2006–07, respectively). The observed and simulated soil organic carbon (SOC) reasonably agreed during RothC model validation (R 2 = 0.99). Economic analysis showed the maximum net profit and relative increase in income ($729 US ha?1 and 309%, respectively) from inorganic treatment. Application of synthetic fertilizers increased grain yield and farm profit while organic manure enhanced grain quality. The RothC model had potential for determining the SOC in organic farming under arid environment.  相似文献   
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The objective of this work was to develop sustained-release Ca-alginate beads of apigenin using sodium alginate, a natural polysaccharide. Six batches were prepared by applying the ionotropic gelation technique, wherein calcium chloride was used as a crosslinking agent. The beads were evaluated for particle size, drug loading, percentage yield, and in vitro drug release. Particle size was found to decrease, and drug entrapment efficiency was enhanced with an increase in the polymer concentration. The dissolution study showed sustained drug release from the apigenin-loaded alginate beads with an increase in the polymer proportion. Based on the dissolution profiles, BD6 formulation was optimized and characterized for FTIR, DSC, XRD, and SEM, results of which indicated successful development of apigenin-loaded Ca alginate beads. MTT assay demonstrated a potential anticancer effect against the breast cancer MCF-7 cell lines. The antimicrobial activity exhibited effective inhibition in the bacterial and fungal growth rate. The DPPH measurement revealed that the formulation had substantial antioxidant activity, with EC50 value slightly lowered compared to pure apigenin. A stability study demonstrated that the BD6 was stable with similar (f2) drug release profiles in harsh condition. In conclusion, alginate-based beads could be used for sustaining the drug release of poorly water-soluble apigenin while also improving in vitro antitumor, antimicrobial, and antioxidant activity.  相似文献   
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Plant Foods for Human Nutrition - Herbal teas are used as therapeutic vehicles in many forms of traditional medicine and are a popular global beverage. The purpose of this scoping review was to...  相似文献   
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Tropical Animal Health and Production - Newcastle disease (ND) is a devastating disease and cause high t mortality and morbidity in poultry and nonpoultry avian species worldwide. An intensive...  相似文献   
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Comparative functional responses (FRs) can predict impacts of invasive species, including piscivorous fishes, via quantifying their depletion of native food resources as a function of prey density. The utility of FRs for predicting impacts on prey populations by invasive fishes of different trophic guilds was tested here by comparing the FRs of the invaders Cyprinus carpio and Carassius auratus, with three native, trophically analogous fishes, Barbus barbus, Squalius cephalus and Tinca tinca. Chironomid larvae and Gammarus pulex were used as prey items. Predictions, developed from studies on the foraging of C. carpio and C. auratus in the literature, were that the invaders would have significantly higher consumption rates for chironomids than the native fishes, but not for G. pulex. Mean consumption rates for chironomids were significantly lower for both invaders than B. barbus and S. cephalus, but were similar to T. tinca. Barbus barbus had a significantly lower consumption rate of G. pulex than both invaders, but there were no significant differences between S. cephalus, T. tinca and the invaders. All FRs were type II, with FR curves for the invaders preying upon chironomids never being significantly higher than the native fishes, contrary to predictions. For G. pulex, some significant differences were apparent between the invaders and native fishes, but again were contrary to predictions. These results indicated that when predation impacts of invasive fishes could also be a function of their population density and body sizes, these parameters should be incorporated into FR models to improve impact predictions.  相似文献   
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A 3 × 3 factorial experiment was conducted on Labeo rohita fingerlings to evaluate the effect of dietary oxidized oil and vitamin E. Nine experimental diets were made, based on three degrees of oil oxidation (fresh oil, low oil oxidation and high oil oxidation), and each level of oxidation was further supplemented with three levels of vitamin E (0, 100 and 1,000 mg/kg). Weight gain% and specific growth rate (SGR) of fish fed fresh fish oil and low oil oxidation level were significantly higher than highly oxidized oil. Moreover, vitamin E supplemented fish also showed better growth performance. Oil oxidation caused a significant reduction in the concentrations of α‐tocopherol and increase in TBARS level and antioxidant enzyme activities in fish liver and muscles. However, increasing the dietary vitamin E abrogated these effects. Dietary vitamin E supplementation improved the fatty acid, more specifically polyunsaturated fatty acids profile of oxidized oil fed fish. In conclusion, dietary oxidized fish oil increased the oxidative stress condition of fish but supplementation of high dose of vitamin E prevented lipid oxidation, improved growth performance and fatty acid profile of L. rohita.  相似文献   
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