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81.
对16~46周龄的蛋鸡生产性能的研究表明,交替饲喂或喂混合饲料的效果是不同的。一种方法是利用同等比例的整粒小麦或营养均衡的含蛋白质及矿物质浓缩的饲料交替饲喂ISA布朗母鸡,另一种方法是饲喂混合饲料。对照组喂传统的饲料。每组16笼,每笼中5只鸡。每天光照时间16h。控制饲料的饲喂量,121g·只-·1d-1,每天饲喂2次,分别为开灯后4h和11h。在交替饲喂时,仅第1次喂食小麦,第2次喂食营养的均衡饲料。喂混合饲料时,两种定量配给的饲料混合喂2次。在下一次喂食前拿走剩余的饲料。与喂混合饲料和对照组相比,交替饲喂减少总采食量,小麦减少9g·只-·1d-1,但喂均衡饲料增多1.7g·只-·1d·-1。在3种方式中,鸡蛋的生产,蛋的大小,蛋的重量均相似。交替饲喂与喂混合饲料相比,饲料利用率的提高分别为10%和5%。与喂混合饲料和对照组相比,交替饲喂ME低,CP摄取量减少。交替饲喂时蛋鸡体重轻,其肌胃、胰腺和肝脏较重,肝脏脂质类似。喂混合饲料肝糖最高。试验结论为,交替饲喂整粒小麦和营养均衡的饲料或喂混合饲料对蛋鸡生产无负面影响。因此,两种饲喂方法是可以替代传统的喂养方式。与喂混合饲料相比,交替饲喂饲料的利用效率高,因而是可行的。 相似文献
82.
Assessment and monitoring of soil quality using near-infrared reflectance spectroscopy (NIRS) 总被引:3,自引:0,他引:3
L. Cécillon B. G. Barthès C. Gomez D. Ertlen V. Genot M. Hedde A. Stevens & J. J. Brun 《European Journal of Soil Science》2009,60(5):770-784
Soil degradation processes have dramatically increased in their extent and intensity over the last decades. Progressively, actions have been taken in order to evaluate and reduce the major threats that have already wreaked havoc on soil conditions. Efficient and standardized monitoring of soil conditions is thus required but soil quality research is facing an important technological challenge because of the number of properties involved in soil quality. The objective of the present review is to examine critically the suitability of near-infrared reflectance spectroscopy (NIRS) as a tool for soil quality assessment. We first detail the soil quality-related parameters (chemical, physical and biological) that can be predicted with NIRS through laboratory measurements. The ability of imaging NIRS (airborne or satellite) for mapping a minimum data set of soil quality is also discussed. Then we review the most recent research using soil reflectance spectra as an integrated measure of soil quality, from global site classification to the prediction of specific soil quality indices. We conclude that imaging NIRS enables the direct mapping of some soil properties and soil threats, but that further developments to solve several technological limitations identified are needed before it can be used for soil quality assessment. The robustness of laboratory NIRS for soil quality assessment allows its implementation in soil monitoring networks. However, its routine use requires the development of international soil spectral libraries that should become a priority for soil quality research. 相似文献
83.
Day L Gomez J Øiseth SK Gidley MJ Williams BA 《Journal of agricultural and food chemistry》2012,60(12):3282-3290
Plant cell walls are the major structural component of fruits and vegetables, which break down to cell wall particles during ingestion (oral mastication) or food processing. The major health-promoting effect of cell walls occurs when they reach the colon and are fermented by the gut microbiota. In this study, the fermentation kinetics of carrot cell wall particle dispersions with different particle size and microstructure were investigated in vitro using porcine feces. The cumulative gas production and short-chain fatty acids (SCFAs) produced were measured at time intervals up to 48 h. The results show that larger cell clusters with an average particle size (d(0.5)) of 298 and 137 μm were more rapidly fermented and produced more SCFAs and gas than smaller single cells (75 μm) or cell fragments (50 μm), particularly between 8 and 20 h. Confocal microscopy suggests that the junctions between cells provides an environment that promotes bacterial growth, outweighing the greater specific surface area of smaller particles as a driver for more rapid fermentation. The study demonstrates that it may be possible, by controlling the size of cell wall particles, to design plant-based foods for fiber delivery and promotion of colon fermentation to maximize the potential for human health. 相似文献
84.
85.
VP Dia T Gomez G Vernaza M Berhow YK Chang EG de Mejia 《Journal of agricultural and food chemistry》2012,60(32):7886-7894
Soybean contains constituents that have antinutritional and bioactive properties. Enzymatic hydrolysis and germination can enhance the biological activity of these compounds in soybean. The objective of this study was to investigate the effect of germination, Alcalase (protease) hydrolysis, and their combination on the concentrations of antinutritional and bioactive compounds in Brazilian soybean cultivar BRS 133. A combination of germination and Alcalase hydrolysis resulted in the degradation of Bowman-Birk inhibitor (BBI), Kunitz trypsin inhibitor (KTI), and lunasin by 96.9, 97.8, and 38.4%. Lectin was not affected by any of the processing treatments when compared to nongerminated and nonhydrolyzed soy protein extract. Total isoflavones (ISF) and total saponins (SAP) increased by 16.2 and 28.7%, respectively, after 18 h of germination, while Alcalase hydrolysis led to the reduction of these compounds. A significant correlation was found between concentrations of BBI and KTI, BBI and lunasin, BBI and ISF, KTI and lunasin, KTI and ISF, KTI and SAP, lunasin and ISF, and ISF and SAP. Germination and Alcalase hydrolysis interacted in reducing BBI, ISF, and SAP. This study presents a process of preparing soy flour ingredients with lower concentrations of antinutritional factors and with biologically active constituents, important for the promotion of health associated with soybean consumption. In conclusion, 18 h of germination and 3 h of Alcalase hydrolysis is recommended for elimination of protease inhibitors, while bioactives are maintained by at least 50% of their original concentrations. 相似文献
86.
Summary During the past two decades total potato production in Colombia tripled and the annual consumption per capita doubled; the
National Potato Programme has probably contributed greatly to these increases. The main activities of this Programme have
been in breeding and in successful introduction of new cultivars. This could be achieved because (1) breeding is oriented
to the requirements of the growers, (2) breeding is done at high altitude where 85% of the area cropped with potato is located
and virus infection pressure is low, (3) the introduction of new cultivars is well organized and (4) with the new cultivars
clear instructions on pest and disease control and on growing techniques are given. 相似文献
87.
Background
The effects of lighting on the human circadian system are well-established. The recent discovery of 'non-visual' retinal receptors has confirmed an anatomical basis for the non-image forming, biological effects of light and has stimulated interest in the use of light to enhance wellbeing in the corporate setting. 相似文献88.
CA Letelier MA Sanchez RA Garcia‐Fernandez B Sanchez P Garcia‐Palencia A Gonzalez‐Bulnes JM Flores 《Reproduction in domestic animals》2011,46(3):481-488
The aim of the current study was to determine the possible effects of progestagen oestrous synchronization on vascular endothelial growth factor (VEGF) expression during sheep luteogenesis and the peri‐implantation period and the relationship with luteal function. At days 9, 11, 13, 15, 17 and 21 of pregnancy, the ovaries from 30 progestagen treated and 30 ewes cycling after cloprostenol injection were evaluated by ultrasonography and, thereafter, collected and processed for immunohistochemical evaluation of VEGF; blood samples were drawn for evaluating plasma progesterone. The progestagen‐treated group showed smaller corpora lutea than cloprostenol‐treated and lower progesterone secretion. The expression of VEGF in the luteal cells increased with time in the cloprostenol group, but not in the progestagen‐treated group, which even showed a decrease between days 11 and 13. In progestagen‐treated sheep, VEGF expression in granulosa‐derived parenchymal lobule capillaries was correlated with the size of the luteal tissue, larger corpora lutea had higher expression, and tended to have a higher progesterone secretion. In conclusion, the current study indicates the existence of deleterious effects from exogenous progestagen treatments on progesterone secretion from induced corpora lutea, which correlate with alterations in the expression of VEGF in the luteal tissue and, this, presumably in the processes of neoangiogenesis and luteogenesis. 相似文献
89.
A‐S Bergqvist A Johannisson L Bäckgren A‐M Dalin H Rodriguez‐Martinez JM Morrell 《Reproduction in domestic animals》2011,46(1):e74-e78
This study was designed to evaluate the effect of single layer centrifugation (SLC) and subsequent cold storage on stallion sperm capacitation‐like status and acrosome reaction. Three stallions were included in the study, with three ejaculates per stallion. The samples were examined 4, 24 and 72 h after collection, extension and SLC, with storage at 6°C. Sperm capacitation‐like status was investigated using the fluorescent dye chlortetracycline (CTC). There was no difference in capacitation‐like status between colloid‐selected and non‐selected spermatozoa. Sperm motility decreased significantly during cold storage, whereas the proportion of apparently capacitated spermatozoa increased. There was no change in the proportion of acrosome‐reacted spermatozoa. In conclusion, SLC through Androcoll?‐E does not adversely affect the capacitation‐like status of stallion spermatozoa, although it did increase with time during cold storage. 相似文献
90.
Sánchez Ramos O González Pose A Gómez-Puerta S Noda Gomez J Vega Redondo A Águila Benites JC Suárez Amarán L Parra NC Toledo Alonso JR 《Comparative immunology, microbiology and infectious diseases》2011,34(3):259-265
Recombinant adenoviral vectors have emerged as an attractive system for veterinary vaccines development. However, for poultry vaccination a very important criterion for an ideal vaccine is its low cost. The objective of this study was to test the ability of chicken CD154 to enhance the immunogenicity of an adenoviral vector-based vaccine against avian influenza virus in order to reduce the amount of antigen required to induce an effective immune response in avian. Chickens were vaccinated with three different doses of adenoviral vectors encoding either HA (AdHA), or HA fused to extracellular domain chicken's CD154 (AdHACD). Hemagglutination inhibition (HI) assay and relative quantification of IFN-γ showed that the adenoviral vector encoding for the chimeric antigen is able to elicit an improved humoral and cellular immune response, which demonstrated that CD154 can be used as a molecular adjuvant allowing to reduce in about 50-fold the amount of adenoviral vector vaccine required to induce an effective immune response. 相似文献