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321.
The aim of the study was to investigate the ability of gamma-tocopherol, ethylenediaminetetraacetate (EDTA), and ascorbyl palmitate to protect fish oil enriched salad dressing against oxidation during a 6 week storage period at room temperature. The lipid-soluble gamma-tocopherol (220 and 880 microg g-1 of fish oil) reduced lipid oxidation during storage by partly retarding the formation of lipid hydroperoxides (PV) and by decreasing the concentrations of individual volatile oxidation products by 34-39 and 42-66%, respectively. EDTA (10 and 50 microg g-1 of dressing) was the most efficient single antioxidant, and overall peroxide values and volatiles were reduced by approximately 70 and 77-86%, respectively. Conversely, prooxidant effects were observed with a high concentration of ascorbyl palmitate (300 microg g-1 of fish oil), whereas a low concentration was slightly antioxidative (50 microg/g of fish oil). Finally, a combination of all three antioxidants completely inhibited oxidation during storage, indicating that the prooxidant effects of ascorbyl palmitate were reverted or overshadowed by EDTA and gamma-tocopherol.  相似文献   
322.
OBJECTIVE: To measure change in fruit and vegetable (F&V) consumption among elementary-school children after the introduction of a salad bar programme as a lunch menu option in the US Department of Agriculture's (USDA) reimbursable lunch programme in Los Angeles Unified School District (LAUSD). DESIGN: A cross-sectional sample of children was interviewed before and after a salad bar intervention (1998 and 2000, respectively) utilising a 24-hour food recall questionnaire. Frequencies of F&V consumption were calculated. SETTING: The evaluation took place in three LAUSD elementary schools participating in the salad bar programme and the USDA reimbursable lunch programme. SUBJECTS: Three hundred and thirty-seven children in 2nd-5th grade (7-11 years old). RESULTS: After the salad bar was introduced, there was a significant increase in frequency (2.97 to 4.09, P < 0.001) of F&V consumed among the children studied. The increase in frequency of F&V consumed was almost all due to an increase during lunch (84%). Mean energy, cholesterol, saturated fat and total fat intakes were significantly lower in the children after the salad bar was introduced in the schools compared with the intakes in the children before the salad bar was introduced.Conclusion: A salad bar as a lunch menu option in the USDA reimbursable lunch programme can significantly increase the frequency of F&V consumption by elementary-school children living in low-income households.  相似文献   
323.
OBJECTIVE: To develop and evaluate a marker cluster set for measuring sagittal and extrasagittal movement of joints in the distal portion of the forelimb in ponies. ANIMALS: 4 ponies. PROCEDURES: 5 infrared cameras were positioned on a concrete walkway in a frontal-sagittal arc and calibrated. Four segments were defined: hoof, middle phalanx, proximal phalanx, and metacarpus. Rigid clusters with 4 retroreflective markers were placed on each segment. A static trial was recorded with additional anatomic markers on the medial and lateral joint lines. Those anatomic markers were removed, and kinematic data were recorded at 240 Hz during walking. An ensemble mean was computed from the 4 ponies from 5 replicates of the walks. Joint kinematic variables were calculated by use of the calibrated anatomical system technique. The design and error dispersion of each marker were evaluated. RESULTS: Marker clusters were quasiplanar, but variation in orientation error was reduced because the mean radii were > 10 times the largest error dispersion values. Measurements of sagittal rotations of the distal interphalangeal, proximal interphalangeal, and metacarpophalangeal joints were similar to measurements obtained with bone-fixed triads, but larger discrepancies between the 2 methods were found for extrasagittal rotations. CONCLUSIONS AND CLINICAL RELEVANCE: Development of noninvasive methods for quantifying data pertaining to 3-dimensional motion in horses is important for advancement of clinical analysis. The technique used in the study enabled identification of flexion-extension motions with an acceptable degree of accuracy. Appropriate correction algorithms and improvements to the technique may enable future quantification of extrasagittal motions.  相似文献   
324.
In the last decade, the veterinary profession has experienced many changes, including the birth of a new area of law known as "animal law," and an increased scrutiny by the legal community and veterinary state boards. This article provides a sampling of some of the more challenging issues the profession is facing in the early part of the 21st century, namely, guardianship versus ownership, the awarding of non-economic damages in negligence lawsuits, and challenges in maintaining medical records.  相似文献   
325.
The aim of this study was to investigate the effect of combined atropine low-dose dobutamine stress test on left ventricular parameters in adult warmblood horses, to establish a potential protocol for pharmacological stress echocardiography. Seven healthy untrained warmblood horses aged 9 to 22 years were used. Heart rate (HR) and left ventricular B- and M-mode dimensions were recorded at baseline and during stress testing with 35 microg/kg atropine IV followed by incremental dobutamine infusion of 2 to 6 microg/kg/min. HR increased significantly (P < .05) during the pharmacological challenge, and a maximal HR of 156.6 +/- 12.5 bpm was reached at maximal dobutamine infusion rate. Systolic and diastolic interventricular septum thickness, systolic and diastolic left ventricular free wall thickness, and fractional shortening increased significantly and reached a maximum at the highest infusion rate (mean +/- SD: 4.51 +/- 0.27 versus 5.65 +/- 0.31 cm, 2.89 +/- 0.19 versus 3.78 +/- 0.10 cm, 3.72 +/- 0.34 versus 4.77 +/- 0.18 cm, 2.44 +/- 0.28 versus 3.11 +/- 0.34 cm, 34.98 +/- 3.82 versus 50.56 +/- 3.42%, respectively). Systolic and diastolic left ventricular internal diameter decreased significantly during dobutamine infusion. Left ventricular external and internal area were significantly lower at a dobutamine infusion rate of 2 microg/kg/min but no further decrease was observed during the subsequent steps. Systolic and diastolic myocardial area was significantly lower after the administration of dobutamine but not significantly different during dobutamine infusion, when compared to baseline values. This pharmacological stress test induced significant changes in left ventricular echocardiographic parameters in adult warmblood horses. Additional research should evaluate the value of this stress test in horses suffering from cardiac disease.  相似文献   
326.
Modern animal scientists, industry, and managers have never faced a more complex world. Precision livestock technologies have altered management in confined operations to meet production, environmental, and consumer goals. Applications of precision technologies have been limited in extensive systems such as rangelands due to lack of infrastructure, electrical power, communication, and durability. However, advancements in technology have helped to overcome many of these challenges. Investment in precision technologies is growing within the livestock sector, requiring the need to assess opportunities and challenges associated with implementation to enhance livestock production systems. In this review, precision livestock farming and digital livestock farming are explained in the context of a logical and iterative five-step process to successfully integrate precision livestock measurement and management tools, emphasizing the need for precision system models (PSMs). This five-step process acts as a guide to realize anticipated benefits from precision technologies and avoid unintended consequences. Consequently, the synthesis of precision livestock and modeling examples and key case studies help highlight past challenges and current opportunities within confined and extensive systems. Successfully developing PSM requires appropriate model(s) selection that aligns with desired management goals and precision technology capabilities. Therefore, it is imperative to consider the entire system to ensure that precision technology integration achieves desired goals while remaining economically and managerially sustainable. Achieving long-term success using precision technology requires the next generation of animal scientists to obtain additional skills to keep up with the rapid pace of technology innovation. Building workforce capacity and synergistic relationships between research, industry, and managers will be critical. As the process of precision technology adoption continues in more challenging and harsh, extensive systems, it is likely that confined operations will benefit from required advances in precision technology and PSMs, ultimately strengthening the benefits from precision technology to achieve short- and long-term goals.  相似文献   
327.
  • 1. The provision of Canadian and US hard, enforceable, law to authorize rapid response management of nonindigenous aquatic species originating from aquaculture, live fish sales, bait fish, and the pet trade was analysed at the provincial/state levels of government for the Atlantic, Laurentian Great Lakes, and Pacific regions of North America.
  • 2. No federal legal capacity for rapid response management exists in either country. US state legislation is generally better developed than Canadian provincial laws to manage the exotic fish trade. However, much discrepancy exists among provincial and state law regarding provisions to restrict or prohibit potentially harmful species. Aquaculture and baitfish use is generally better regulated than live fish markets and the pet fish trade in both countries. Only the state of Maine has laws authorizing rapid‐response management to control escaped exotic fish.
  • 3. Most species of nonindigenous fish arise from the aquarium, pet, and baitfish trades, and development of improved legislation containing provisions for rapid response management of escapees is warranted in all states and provinces.
  • 4. It is recommended that Canada amends the Fisheries Act to create the appropriate enabling legislation to monitor, assess risk, and deploy rapid response management of nonindigenous aquatic species, including fish that enter federal fresh and sea waters. Two recently‐introduced US Bills, S. 725 and H.R. 1350, with their explicit measures for early detection and fast action response, could, if passed into law, create provisions to control introduced nuisance species throughout North American waters. They would also create precedents for states and provinces that have most jurisdiction over aquaculture and trade in exotic fish to amend and align their laws in a complementary manner.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
328.
Development of objectionable fishy off-flavors is an obstacle in the development of fish oil enriched foods. Only little is known about the sensory impact of specific volatile fish oil oxidation products in food emulsions. This study examined the volatiles profiles of fish oil enriched milk during cold storage (2 degrees C) for 14 days by dynamic headspace sampling followed by gas chromatography-mass spectrometry analyses. Different volatiles (n = 60) comprising alkenals, alkadienals, alkatrienals, and vinyl ketones were identified in the fish oil enriched milk. The potent odorants identified by gas chromatography-olfactometry were 1-penten-3-one, (Z)-4-heptenal, 1-octen-3-one, (Z)-1,5-octadien-3-one, (E,E)-2,4-heptadienal, and (E,Z)-2,6-nonadienal, but despite their potency, none of the separated volatiles imparted a fishy or metallic odor. Two isomers, (E,Z,Z) and (E,E,Z) of 2,4,7-decatrienal were identified in fish oil enriched milk emulsions with peroxide values 0.8 and 3.4 meq/kg, respectively. To our knowledge, this is the first report on appearance of these decatrienals in food emulsions having a relatively low peroxide value.  相似文献   
329.
330.
The distribution of molybdenum in tomatoes, sunflowers and beans and their sensitivity towards molybdenum. The influence of increasing levels of molybdenum on the growth, molybdenum uptake and distribution in individual plant organs was investigated in tomatoes, beans and sunflowers in a 9 day trial. With tomatoes, which showed marked damage with high molybdenum levels, the molybdenum content of dry matter was highest in the leaf and lowest in the stem. On the otherhand, beans, insensitive towards the high molybdenum level, dry matter molybdenum content was appreciably higher in the stem than in the leaf. It is supposed that in plant species, insensitive to high molybdenum levels, such as beans, molybdenum preferably accumulates in the vacuoles of the vascular parenchyma. In contrast in tomatoes, sensitive to high molybdenum levels, molybdenum is held less firmly in this tissue and can attain damaging levels in the cytoplasm of the youngest leaf tissue cells. It is supposed, on the basis of the reactions which were carried out with expressed root juice and on the basis of the yellow colouration attainable in vitro in the tissue caused by the addition of molybdate solution, that the yellow colouration appearing in the cells and plant organs of various plant species, here tomatoes and sunflowers, with high molybdenum levels is due to a reaction between molybdenum and polyvalent phenols in cellsap.  相似文献   
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