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11.
Effect of diet and dietary fatty acids on the transformation and incorporation of C18 fatty acids in double-muscled Belgian Blue young bulls 总被引：2，自引：0，他引：2
Raes K Fievez V Chow TT Ansorena D Demeyer D De Smet S 《Journal of agricultural and food chemistry》2004,52(19):6035-6041
Three groups of double-muscled Belgian Blue young bulls were fed during different stages of production diets differing in the proportions of linolenic and linoleic acid by including linseed in the concentrate or giving grass silage as main linolenic acid suppliers. Samples of rumen and abomasal contents and of the longissimus thoracis, subcutaneous fat, and liver were taken to analyze the fatty acid pattern with emphasis on the individual trans (t) C18:1 fatty acids and cis-9,trans-11 conjugated linoleic acid (c9t11CLA). Trans C18:1 isomers represented up to 20 g/100 g of total fatty acids in rumen and abomasal contents, whereas the accumulation of c9t11CLA was limited. Total trans C18:1 content in subcutaneous fat and intramuscular fat of the longissimus thoracis comprised 8.4 and 5.2 g/100 g of total fatty acids, respectively, with t11C18:1 being the most abundant one. Compared to rumen contents, subcutaneous and intramuscular fat were enriched in c9t11CLA and contained fewer tC18:1 isomers, resulting in a higher c9t11CLA/t11C18:1 ratio (0.04, 0.22, and 0.22, respectively). This result suggests that the endogenous synthesis of c9t11CLA in adipose tissue by the Delta(9)-desaturase was more important than its ruminal production. 相似文献
12.
Fermented liquid feed is feed that has been mixed with water at a ratio ranging from 1:1.5 to 1:4. By mixing with water, lactic acid bacteria and yeasts naturally occurring in the feed proliferate and produce lactic acid, acetic acid and ethanol which reduces the pH of the mixture. This reduction in pH inhibits pathogenic organisms from developing in the feed. In addition, when this low pH mixture is fed, it reduces the pH in the stomach of pigs and prevents the proliferation of pathogens such as coliforms and Salmonella in the gastrointestinal tract. For piglets, the use of fermented liquid feed offers the possibility of simultaneously providing feed and water, which may facilitate an easier transition from sow’s milk to solid feed. Secondly, offering properly produced fermented liquid feed may strengthen the role of the stomach as the first line of defense against possible pathogenic infections by lowering the pH in the gastrointestinal tract thereby helping to exclude enteropathogens. Finally, feeding fermented liquid feed to pigs has been shown to improve the performance of suckling pigs, weaner pigs and growing-finishing pigs. In this review, current knowledge about the use of fermented liquid feed in pig diets will be discussed. This will include a discussion of the desirable properties of fermented liquid feed and factors affecting fermentation. In addition, advantages and disadvantages of fermented liquid feed will be discussed including its effects on gastrointestinal health, intestinal pH and the types of bacteria found in the gastrointestinal tract as well as the effects of fermented liquid feeds on pig performance. 相似文献
13.
The very-high-resolution radiometer on the NOAA-2 (National Oceanic and Atmospheric Administration) satellite has recently obtained imagery in the visible channel containing sunglint over a major portion of the coastal waters off the eastern seaboard of the United States. An abrupt change in surface roughness has been observed at the shoreward edge of the Gulf Stream Current from Florida to Cape Hatteras that results from the opposition of waves propagating against the flow of the Gulf Stream. 相似文献
14.
V. Derycke G.E. Vandeputte R. Vermeylen W. De Man B. Goderis M.H.J. Koch J.A. Delcour 《Journal of Cereal Science》2005,42(3):334-343
Starch gelatinization and formation of crystalline amylose–lipid complexes during the heat/moisture treatment step in rice parboiling were studied with temperature resolved wide angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) using flour from Puntal (24% apparent amylose) and Jacinto (12% apparent amylose) rice samples [66, 40 or 25% moisture content (mc)]. Temperature resolved WAXS showed that the crystallinity index (CI, i.e. the relative amount of A-type crystals) of non-parboiled rice flours at 66% mc, monotonically decreased between 65 °C (Puntal) and 70 °C (Jacinto) and 90 °C (both Puntal and Jacinto). These temperatures were in agreement with the respective onset and conclusion temperatures of the M1 endotherm measured by DSC. At 40% mc, the CI decreased monotonically from 65 °C (Puntal) and 70 °C (Jacinto) until 105 °C. In DSC both M1 and M2 endotherms were present. The conclusion temperature of the M2 endotherm was higher than 105 °C. At 25% mc, the CI decreased very gradually and A-type crystals were no longer present at 145 °C. Under these conditions, no DSC endotherms were detected. No type II amylose–lipid complexes were formed during heating at 66% mc. In contrast, at 40 and 25% mc, Vh-type crystals were formed from 100 and 130 °C, respectively. Non-parboiled white rice flour had a strong A-type pattern. Mildly parboiled rice had a clear A-type, with a weak Vh-type and B-type pattern. Severe parboiling resulted in partially crystalline systems with superimposed A-type, Vh-type and B-type crystals. It was concluded that the rice variety, the combination of mc and the moisture distribution in the rice kernel and the temperature during parboiling all impact the level and the types of crystals in the parboiled rice. 相似文献
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Jones Yengwe Mesfin Tsegaye Gebremikael David Buchan Obed Lungu Stefaan De Neve 《Agroforestry Systems》2018,92(2):349-363
The nitrogen status of most Zambian soils is inherently low. Nitrogen-fixing trees such as Faidherbia albida (F. albida) could have the potential to restore soil fertility. We conducted a study to examine the role of mature F. albida trees on the soil microbial communities and overall N fertility status in Zambia. Soil samples were collected under and outside the canopies of F. albida trees in representative fields from two sites namely; Chongwe (loamy sand) and Monze (sandy loam). To assess the long term canopy effects; total N, mineral N and soil organic carbon (Corg) content were directly measured from soils collected under and outside the canopy. Short term litter effects were assessed by subtracting concentrations of biochemical properties of non-amended controls from amended soils with F. albida litter during an 8 week incubation experiment. We also determined N mineralization rates, microbial community structure—Phospholipid fatty acids, microbial biomass carbon, and labile organic carbon (\({\text{C}}_{{{\text{org[K}}_{ 2} {\text{SO}}_{ 4} ]}}\)) during incubation. For the long term canopy effect, average N mineralization rate, Corg, total N and mineral N content of non-amended soils under the canopy were (all significant at p < 0.05) greater than soils outside the canopy on both sites. In the short term, amending soils with litter significantly increased N mineralization rates by an average of 0.52 mg N kg?1 soil day?1 on soil from Monze. Microbial biomass carbon measured after 4 weeks of incubation was on average significantly higher on amended soils by 193 and 334 mg C kg?1 soil compared with non-amended soils in Chongwe and Monze soils, respectively. After 6 weeks of incubation, the concentration of all selected biomarkers for major microbial groups concentrations in non-amended soils were significantly higher (all p < 0.05) under the canopy than outside in Monze soil. Using principal component analysis, we found that the segregation of the samples under and outside the canopy by the first principal component (PC1) could be attributed to a proportional increase in abundances of all microbial groups. Uniform loadings on PC1 indicated that no single microbial group dominated the microbial community. The second principal component separated samples based on incubation time and location. It was mainly loaded with G-positive bacteria, and partly with G-negative bacteria, indicating that microbial composition was dominated by these bacterial groups probably at the beginning of the incubation on Monze soils. Our results show that the improvement of soil fertility status by F. albida could be attributed to a combination of both long term modifications of the soil biological and chemical properties under the canopy as well as short term litter fall addition. 相似文献
17.
Inge Mestdagh Steven Sleutel Peter Lootens Oswald Van Cleemput Daan Beheydt Pascal Boeckx Stefaan De Neve George Hofman Nancy Van Camp Inge Vande Walle Roeland Samson Kris Verheyen Raoul Lemeur Lucien Carlier 《植物养料与土壤学杂志》2009,172(1):24-31
Total soil organic‐carbon (SOC) stocks for grassland soils in Flanders (N Belgium) were determined for the Kyoto Protocol reference year 1990 and 2000 in order to investigate whether these soils have been CO2 sinks or sources during that period. The stocks were calculated by means of detailed SOC datasets, which were available at the community scale for the whole of Flanders. The total SOC stocks for Flemish grassland soils (1 m depth) were estimated at 38 Mt SOC in 1990 and 34 Mt SOC in 2000. The loss of SOC resulted from a decrease in the SOC content of grassland soils (71%) and could also partly (29%) be explained by a decline in grassland area. Significant decreases in %SOC for the 0–6 cm depth layer were found for the 1990s for the coarser‐textured soils with SOC losses ranging between –0.3% and –0.5% over the 10 y period. Specific management practices that disturb the SOC balance such as conversion to temporary grassland and a reduction of animal‐manure application are hypothesized to have contributed to the observed loss of SOC stocks. We furthermore conducted an analysis of uncertainty of the 1990 and 2000 grassland SOC–stocks calculation using Monte Carlo analysis. Probability‐distribution functions were determined for each of the inputs of the SOC‐stock calculation, enabling us to assess the uncertainty on the 1990 and 2000 SOC stocks. The frequency distributions of these simulated stocks both closely approached lognormal distributions, and their 95%‐confidence intervals ranged between 150% and 50% of the calculated mean SOC stock. The standard error on the measured decrease in SOC stocks in Flemish grassland soils during the 1990s was calculated to be 7–8 Tg SOC, which is equivalent to twice this decrease. This clearly shows that large‐scale changes in SOC stocks are uncertainty‐ridden, even when they are based on detailed datasets. 相似文献
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Stany Vandermoere Tomas Van De Sande Greet Tavernier Lore Lauwers Ellen Goovaerts Joris De Nies Stefaan De Neve 《植物养料与土壤学杂志》2020,183(3):345-354
Environmental concerns and rapidly decreasing phosphorus (P) resources caused a renewed interest in improving soil P tests for a more efficient P fertilization. This led to the development of better P fertilizer recommendation systems for major arable crops and grass. Nevertheless, these P fertilizer recommendation systems seem to fail for intensive vegetable crops, with often a very short growing season and limited rooting system. This leads to low P use efficiencies in the horticultural sector. In order to address this problem we set up a study to answer following questions: (1) which soil P test predicts the plant available P content for intensive vegetable crops the best and (2) can new insights, such as combining different soil P tests, improve P fertilizer recommendations for intensive vegetable crops? To this end, bulk samples of 41 soils with very different P status (based on ammonium lactate extractable P) were collected. The plant available P content of these soils was determined using six commonly used soil P tests (P‐CaCl2, P‐water, P‐Olsen, P‐acetate, P‐lactate, and P‐oxalate) and a P fertilizer pot experiment with endive (a very P sensitive vegetable crop) was conducted. Six pots of each soil were planted with endive. Three of these pots received no P fertilization (0P) and three pots received ammonium polyphosphate equivalent to 24 kg P ha?1 (24P). All other factors were kept constant. Relative crop yield of the 0P fertilized plants compared to the 24P fertilized plants was determined. Plotting these relative yields against the P status of the soil per soil P test allowed to fit a Mitscherlich curve through the data. Also the combination of two different soil P tests to predict the relative yield with a Mitscherlich equation was evaluated. The coefficients of variation of the soil P tests, the R2 values and the relative standard errors of the parameter estimates revealed that P‐acetate and P‐water predicted the relative yield of the 0P plants the best and that combining two different soil P tests gave no extra predictive power. This finding may form the basis for the development of a new P fertilizer recommendation system for intensive vegetable crops, leading to an improved P use efficiency in horticulture. In order to develop this new system more data relating soil P test values with RY of intensive vegetable crops should be collected. 相似文献
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Barbara Chaves Stefaan De Neve Maria del Carmen Lillo Cabrera Pascal Boeckx Oswald Van Cleemput Georges Hofman 《Biology and Fertility of Soils》2005,41(6):411-418
Manipulating the N release from high-N crop residues by simultaneous mixing of these residues with organic biological waste (OBW) materials seems to be a possible method to reduce NO3– leaching. The aim of this study was to examine whether the incorporation of OBW materials together with a high-N crop residue (celery) had also an effect on N2O emission from horticultural soil under short-term and optimised laboratory conditions. A sandy loam soil and celery residues were mixed with different OBW materials and brought into PVC tubes at 80% water-filled pore space and 15°C. Every 2.5 h, a gas sample was taken and analysed by gas chromatography for its N2O concentration. The soil amended with only celery residues had a cumulative N2O emission of 9.6 mg N kg–1 soil in 50 h. When the celery residues were mixed with an OBW material, the N2O emission was each time lower than the emission from the celery-only treatment (between 3.8 and 5.9 mg N kg–1 soil during maximum 77 h), except with paper sludge (17.2 mg N kg–1 soil in 100 h). The higher N2O emission from the paper sludge treatment was probably due to its unusually low C:N ratio. Straw, green waste compost 1 (GWC1) and 2 (GWC2), saw dust, and tannic acid reduced the N2O emission of the celery treatment by 40 to 60%. Although the N2O reduction potential can be expected to be lower and with differing dynamics under field conditions, this study indicates that apart from reducing NO3– leaching, OBW application may at the same time reduce N2O emissions after incorporation of high-N crop residues. 相似文献
20.
Gardan D Gondret F Van den Maagdenberg K Buys N De Smet S Louveau I 《Domestic animal endocrinology》2008,34(1):45-53
In pigs, a paternally (pat) imprinted mutation in the IGF-II gene is associated with increased muscle mass and decreased backfat thickness. The aim of this study was to determine whether this mutation influenced cellular, biochemical and metabolic features of skeletal muscle and adipose tissue. Muscle (trapezius) and subcutaneous adipose tissue (SCAT) were collected from pigs (106kg) carrying (Qpat, n=6) or not carrying (qpat, n=7) the mutation. Adipocytes were isolated from those tissues by collagenase treatment. Lipid content and activity of lipogenic enzymes were determined using standard assays. Gene expression levels were determined by real-time PCR. Levels of IGF-II mRNA were higher (P<0.01) in muscle of Qpat than in that of qpat pigs, but they did not differ significantly between the two groups in SCAT. Whereas levels of IGF-I mRNA in muscle were similar in both groups, they were higher (P<0.05) in SCAT of Qpat pigs than in that of qpat pigs. Muscle lipid content and intramuscular adipocyte diameters were not influenced significantly by the IGF-II genotype. In SCAT, the reduction of backfat thickness in Qpat pigs compared with qpat pigs was associated with lower (P<0.05) lipid content and smaller (P<0.05) adipocytes, with no significant genotype-effects on expressions and/or activities of lipogenic enzymes. In summary, our results suggest that the IGF-II mutation altered body composition in pigs by favoring myofiber hypertrophy and repressing adipose cell development in SCAT. 相似文献