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New Forests - Previous studies have reported that phosphorus transporters are involved in glyphosate uptake by plants, so phosphorus fertilization might act as an attenuator of glyphosate effects...  相似文献   
2.

The effect of mineral salts on water ingestion and urine volume in cattle has been extensively studied. However, recently, this effect has been investigated as a potential mitigator of environmental aspects related to the nitrogen (N) cycle, such as nitrate (NO3?) lixiviation, ammonia (NH3) volatilisation, and nitrous oxide (N2O) emissions. The effect of mineral salts, particularly sodium chloride (NaCl), on urine-N concentration, urine volume, the proportion of N compounds in the urine, and faecal-N concentration has not yet been explored in field conditions with respect to environmental aspects of beef cattle production. The present study investigated the effect of dietary mineral salt rates on these parameters. A Latin square (5?×?5) experimental design was utilised with five concentrations of mineral salts in the diet: 0.0, 2.0, 4.0, 6.0, and 8.0 g based on dry matter (DM) ingestion (g/kg DM). The nitrogen concentration in the urine and urine volume increased linearly. The total N excreted (g/day) via urine did not vary with increasing mineral salt concentrations. When evaluated, the N compounds of urine (urea-N, allantoin-N, and hippuric acid-N) also reacted to the increased mineral salt concentrations, while creatinine-N did not. Urea-N, allantoin-N, and hippuric acid-N linearly increased their proportions in total N-urine. The N concentration in faeces was not affected by mineral salt concentrations. The urine volume, concentration of N, and proportion of N compounds in the urine affected N2O emissions and NH3 volatilisation. Therefore, mineral salt utilisation may be an option for mitigating N pollution from beef cattle, especially for grasslands in tropical countries.

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3.
This study aimed to characterize the hydroethanolic extract of red propolis (HERP) and nanoparticles containing HERP for using as an additive in the culture medium of isolated ovine preantral follicles. HERP was characterized by high‐performance liquid chromatography (HPLC) and determination of flavonoid content, and the nanoparticles by the mean particle diameter, polydispersity index (PI) and encapsulation efficiency (EE). The effect of HERP (10 and 20 ηg/ml—HERP10 and HERP20 groups) and nanoparticles (NP10 and NP20 groups) on isolated secondary follicles cultured in vitro for 12 days was observed by morphological evaluation, oxidative stress markers (reactive oxygen species—ROS and glutathione—GSH) and active mitochondria. HPLC showed formononetin as the major compound in the HERP (63.92 ± 0.21 μg/mL). The content of flavonoids ranged from 2.14% to 11.00%. The nanoparticles showed mean diameter of 287.5 ± 3.9 and 479 ± 18.1 ηm; PI of 0.117 ± 0.018 and 0.316 ± 0.039; and EE of 67.15% and 41%, respectively, for the NP10 and NP20 groups. After 12 days of culture, HERP20 and NP20 increased (p < 0.05) the percentage of normal follicles compared to NP10. HERP20 showed significantly higher percentages of antrum formation than control medium (MEM) and NP10 (p < 0.05). HERP20 also showed an increase (p < 0.05) in mitochondrial activity compared to the other treatments, except NP20 (p > 0.05), and increased GSH levels (p < 0.05) compared to MEM and HERP10. In conclusion, use of HERP (20 ηg/ml) on in vitro culture of isolated ovine preantral follicles can increase antrum formation, mitochondrial activity and GSH levels.  相似文献   
4.
Tropical Animal Health and Production - The aim of this study was to evaluate the impact of increased shadow supply in integrated crop-livestock-forest systems on in vitro embryonic development and...  相似文献   
5.
In many developing countries, a landfill remains one of the most extensively employed solid waste disposal solutions. Although a landfill is a well-designed engineering system, the base lining of a landfill may perform poorly and allow the leachate to reach the underlying soil layers and groundwater. Leachates contain a variety of toxic and hazardous contaminants, which are attenuated in the soil by various processes that slow or transform them. Thus, the objective of this research was to study the water and leachate permeability and retention of the liner soil in a landfill experimental cell by subjecting it to geotechnical, chemical-mineralogical, and physicochemical characterizations, water and leachate permeability tests, and mercury intrusion porosimetry (MIP). In addition, the water and leachate retention curves were determined and analyzed using RETention Curve (RETC) software to obtain the unsaturated permeability curves. The leachate in the soil decreased the suction considering the moisture content of the compacted soil in the field, which consequently increased the leachate permeability of the mineral liner. For the same suction value, in the drying pathways, the soil retained a greater amount of distilled water than leachate. In the wetting pathways, the opposite occurred. Microorganisms were detected in the soil during the filter paper test. The permeability coefficients of the unsaturated soil were directly proportional to the gravimetric moisture content for the water and the leachate, which demonstrated that the soil presents lower unsaturated permeability coefficients for water than for leachate for the same water content.  相似文献   
6.

Background

Organic vegetable production has a demand for alternative fertilizers to replace fertilizers from sources that are not organic, that is, typically animal-based ones from conventional farming.

Aims

The aim of this study was to develop production strategies of plant-based fertilizers to maximize cumulative nitrogen (N) production (equal to N yield by green manure crops), while maintaining a low carbon-to-nitrogen (C:N) ratio, and to test the fertilizer value in organic vegetable production.

Methods

The plant-based fertilizers consisted of the perennial green manure crops—alfalfa, white clover, red clover, and a mixture of red clover and ryegrass—and the annual green-manure crops—broad bean, lupine, and pea. The crops were cut several times at different developmental stages. The harvested crops were used fresh or pelleted as fertilizers for field-grown white cabbage and leek. The fertilizer value was tested with respect to biomass, N offtake, N recovery, and soil mineral N (Nmin). Poultry manure and an unfertilized treatment were used as controls.

Results

The cumulative N production of the perennial green manure crops ranged from 300 to 640 kg N ha–1 year–1 when cut two to five times. The highest productions occurred at early and intermediate developmental stages, when cut three to four times. Annual green manure crops produced 110–320 kg N ha–1 year–1, since repeated cutting was restricted. The C:N ratio of the green manure crops was 8.5–20.5, and increased with developmental stage. The fertilizer value of green manure, as measured in white cabbage and leek, was comparable to animal-based manure on the condition that the C:N ratio was low (<18). N recovery was 20%–49% for green manure and 29%–42% for poultry manure. A positive correlation was detected between soil Nmin and vegetable N offtake shortly after incorporating the green manure crops, indicating synchrony between N release and crop demand.

Conclusions

Plant-based fertilizers represent highly productive and efficient fertilizers that can substitute conventional animal-based fertilizers in organic vegetable production.  相似文献   
7.
Copper/zinc bioaccumulation and the effect of phytotoxicity on the growth of lettuce (Lactuca sativa L.) were studied in plastic vessels containing (i) non-contaminated soil, (ii) copper-contaminated soils at concentrations of 75.0 and 125.0 mg kg?1, (iii) zinc-contaminated soils at concentrations of 1200 and 2400 mg kg?1, and (iv) soil enriched with swine manure. Copper and zinc concentrations in lettuce leaves were determined by flame atomic absorption spectrometry during 42 days of growth. Copper concentrations from 0.92 to 13.06 mg kg?1 were found in lettuce leaves grown in copper-contaminated soils and zinc concentrations from 58.13 to 177.85 mg kg?1 were found in lettuce leaves grown in zinc-contaminated soils. Copper and zinc concentrations in lettuce leaves grown in swine manure-enriched soils ranged from 0.82 to 8.33 and 0.68 to 13.27 mg kg?1, respectively. Copper and zinc bioaccumulation caused a decrease in lettuce growth in metal-contaminated soils and an increase in phytotoxicity effects when compared to growth in non-contaminated and manure-enriched soils. These findings were confirmed by measuring leaf areas and biomasses. Copper was less toxic to lettuce than zinc due to the different concentrations in the soil. Lettuce growth and development was better in the swine manure-enriched soil than non-contaminated soil, which indicates that swine manure is a safe agricultural biofertilizer when used in appropriate amounts to avoid metal bioaccumulation in soil and plants.  相似文献   
8.
Plant Foods for Human Nutrition - Cardiovascular disease (CVD) is the leading cause of death throughout the world. A major risk factor for CVD is platelet aggregation. Various plant extracts...  相似文献   
9.
The objective of this study was to evaluate the effects of the microalgae Schizochytrium sp., as a dietary source of docosahexaenoic acid (DHA), on diet palatability, coefficients of total tract apparent digestibility (CTTAD) of nutrients and metabolizable energy (ME), blood variables and indicators of immunity in dogs. We also evaluated oxidative stability. Two diets containing 0 and 0.4% of microalgae Schizochytrium sp. were evaluated in three experiments. On Experiment I the palatability of diets containing 0% versus 0.4% microalgae was compared. In Experiment II test diets were offered for 30 days to determine digestibility, fecal characteristics, and blood parameters. In Experiment III, the oxidative stability of diets containing microalgae versus anchovy oil was evaluated. There was a higher intake ratio of the diet containing microalgae (p < .05). The ME and CTTAD of nutrients increased (p < .05), except for ether extract after acid hydrolysis, with the inclusion of the microalgae in diet. The amount of monocytes and phagocytic granulocytes was higher (p < .05) in dogs fed 0.4% microalgae. There was greater oxidative stability for the sample containing microalgae. The addition of 0.4% microalgae presented high palatability, increased phagocytic cell numbers, and demonstrated oxidative stability superior to anchovy oil.  相似文献   
10.
The strong odour of faeces and excessive production of gases in some dog breeds have long been a concern of owners. The pet food industry uses nutritional alternatives, such as high-quality ingredients and additives, to improve the odour of faeces. However, there are still some dog breeds, such as the French Bulldog, that present this problem due to the presence into the large intestine of indigested protein. Therefore, a deeper understanding of the volatile compounds that influence the odour of dog faeces is important. This study aimed to identify changes of faecal odour compounds that are most prevalent in French Bulldogs based on food containing different high-quality protein sources and their effect in sensory analysis. Four maintenance foods with different protein sources were formulated: P, poultry meal food; W, wheat gluten food; PW, poultry meal and wheat gluten food; and PWH, poultry meal, wheat gluten, and hydrolysed protein food. Eight adult French Bulldogs were arranged in a 4x4 Latin square design and adapted to foods for 28 days. Fresh faeces were collected for analysis of volatile organic compounds (VOCs) and sensory analysis. The means were compared by SAS, and statistical significance was indicated by ≤ 0.05. No adverse effects were observed in the animals regarding VOCs, and a significant difference was observed in two of the 68 compounds identified. The animals fed a P food had higher concentrations of phenol in the faeces, whereas the indole compound was present at higher concentrations in animals fed the W food. P food was associated with higher odour perception during sensory evaluation. In summary, the source of protein in the foods had little impact on the composition of VOCs, and a greater perception of the odour was determined by sensory analysis when foods containing animal protein were administered.  相似文献   
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