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991.
不管仔猪断奶早与晚,断奶仔猪的饲喂方案和营养策略应彻底地重新考虑,以确保保育期营养方案的成功实施。设计合理的营养方案和饲料预算不能独自确保保育方案的成功,必须配合其它措施。我们正开始明白,不但给幼龄猪喂什么饲料是重要的,而且教它们怎样采食和如何进行管理同样重要。一个成功的保育期饲喂方案包括多种要素,但最重要的是:A)尽可能从体重较重和日龄较大时开始保育;B)尽可能快地从复杂日粮转换为简单日粮;C)给仔猪提供正确的管理措施,使其能迅速找到食物和饮水,并经常调整喂料器,以获得最佳的饲料效率。 相似文献
992.
Clinical and Clinicopathologic Effects of Large Doses of Raw Linseed Oil As Compared to Mineral Oil in Healthy Horses 总被引:1,自引:0,他引:1
John Schumacher Fred J. DeGraves Joseph S. Spano 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(5):296-299
The clinical and Clinicopathologic effects of raw linseed oil and mineral oil were compared. In a crossover experimental design trial, 6 horses were given either raw linseed oil (2.5 mL/kg body weight) or mineral oil (10 mL/kg body weight), twice, 12 hours apart. Two weeks later, the horses received the opposite treatment. All horses given mineral oil or linseed oil developed nonformed feces by 24 hours of the first administration of oil. Horses treated with mineral oil had formed feces at 48 hours; horses treated with linseed oil developed normally formed feces at 96 to 108 hours. All horses treated with linseed oil had signs of depression and anorexia, and 3 had signs of mild colic. These signs were not observed in horses treated with mineral oil. Concentrations of serum glucose and bilirubin were significantly higher in horses treated with linseed oil when compared with horses treated with mineral oil. 相似文献
993.
M. Barba M. McMaster V. Albanese R. Cole F. Caldwell J. Schumacher 《Equine Veterinary Education》2014,26(7):347-352
A Percheron mare was presented for acute, severe lameness and marked swelling of the right forelimb after being cast. The mare was initially diagnosed with cellulitis of the forelimb but as her condition improved and the affected limb was able to bear more weight it became apparent that the limb was hyperextended at the level of the carpus. Widening of the palmar aspect of the middle carpal joint was observed radiographically. During ultrasonographic examination, excessive fluid in the carpal sheath and perithecal swelling were noted and tearing of the palmar carpal ligament was suspected. A dynamic brace was fabricated to prevent hyperextension of the carpus. After discontinuation of systemic antibiotics, the mare became febrile and forelimb lameness worsened. Cytology of fluid from the middle carpal joint confirmed joint sepsis and the mare was anaesthetised for arthroscopic examination. A tear in the palmar carpal ligament, characterised by focal fibre disruption and fibrillation, was identified during arthroscopic and tenoscopic examination. Communication between the carpal flexor tendon sheath and middle carpal joint was identified during these procedures. Both the middle carpal joint and carpal flexor tendon sheath were lavaged with physiological saline solution. Post operatively, swelling and lameness slowly resolved. Four months after discharge, the mare was sufficiently sound to be maintained at pasture. Viewed from its lateral aspect, the limb no longer appeared to be hyperextended from the carpus. 相似文献
994.
995.
N D Cohen J R Vacek T L Seahorn J R Schumacher 《Journal of the American Veterinary Medical Association》1991,198(6):1035-1036
Unilateral cystic nasal concha was diagnosed in a 6-month-old Brangus male calf by use of endoscopy, radiography, and histologic examination. Cystic nasal conchae have been excised via dorsolateral rhinotomy, but the lesion in the calf of this report was excised transnasally, with considerable ease, using obstetric wire. Postoperative complications did not develop, and the calf was reportedly in good health 3 months after discharge. 相似文献
996.
Background
Plant cell death is a normal process during plant development. Mutant plants may exhibit misregulation of this process, which can lead to severe growth defects. Simple ways of visualising cell death in living plant tissues can aid the study of plant development and physiology. 相似文献997.
Analysis of land-use change in a sector of Upper Franconia (Bavaria,Germany) since 1850 using land register records 总被引:4,自引:3,他引:4
Oliver?Bender Hans Juergen?BoehmerEmail author Doreen?Jens Kim P.?Schumacher 《Landscape Ecology》2005,20(2):149-163
This study analyses changes in the landscape of a sector of Upper Franconia (Bavaria, Germany) by comparing land use changes over four time periods (1850, 1900, 1960, 2000). Geodetic and other data derived from the Bavarian real estate tax and land register were entered into various temporal layers of a land register-based vector GIS. This multitemporal GIS permits a precise analysis of the historical structure and development of landscapes on the basis of land plots.In 1850, the study area was almost exclusively agricultural in structure. Woodlands made up only 18% of the total surface. Rough pastures and wastelands, which covered about 9% of the total surface, were used for grazing. During the first half of the 20th century, the proportion of wooded areas increased considerably. The rough pastures that had formerly been a typical feature of the region nearly disappeared during this period. Agricultural use declined to less than 50% of the total area. In the course of the period between 1960 and 2000, the livestock industry has become an almost exclusively indoor activity. Village development has started spilling over into the adjacent fields. The causes and background of these changes are discussed in detail.From an ecological standpoint, the land use categories surveyed in this analysis of landscape change can be regarded as vegetation types, thereby constituting habitats for specialized biota. The intensity and frequency of any type of land use creates a certain disturbance regime, which disrupts and controls the succession in a certain way. The concept of categories of change incorporated into the GIS helps to evaluate these habitat types and the rate of change more accurately, e.g. for nature conservation purposes. 相似文献
998.
The urban landscape is by nature the result of many cultural and natural factors and processes. Cityscape associated with
land attributes and human activities expresses a city's social and economic functions. Treescape in the form of species composition,
tree dimension and tree performance echoes ecological and environmental functions. The cityscape can be denoted by urban factors,
such as tree growing-space condition, tree management regime, human activities and planting history. The hypothesis that the
cityscape plays a key role in molding the treescape is tested. Nanjing, an east China city notable for its high tree coverage,
is chosen as the study area. A quantitative method has been developed to assess the relationship between cityscape and treescape.
Based on statistical analyses on the surveyed results of 6527 trees and related cityscape attributes, this paper explores
the pertinent patterns and underlying factors of treescape variations. Species composition has the strongest association with
cityscape. Roadside and factories have lower species diversity. Residential and industrial land uses show smaller tree dimension.
Trees in residential, commercial, heavy industrial land-uses perform below par. A three-way classification has been developed
to examine the effects of urban factors on treescape at different cityscape scales. At the small scale, a well-vegetated groundcover
will ensure better tree performance and a lower management burden. The medium-scale cityscape (land-use and habitat) is preferred
in the study of treescape attributes and their spatial variations, and is suitable for urban tree planning and management.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
999.
Landscape Ecology - Quantitative information regarding tree species-specific size is an essential tool for landscape planning. It reflects tree-environment and human–environment interactions... 相似文献
1000.
Tania San Pedro Rosa Peiró Carles Jiménez Antonio Olmos 《The Journal of Horticultural Science and Biotechnology》2018,93(1):19-25
In vitro culture represents a tool for the ex situ conservation of a high number of sanitised plants in a reduced space. However, the culture media and/or other growing conditions need to be optimised to minimising plant growth and storage cost. Growth on MW medium was evaluated in the commercial cultivars ‘Airén’, ‘Bobal’, ‘Chardonnay’, ‘Garnacha Blanca’, ‘Moscatel de Alejandría’, ‘Moscatel de Grano Menudo’, ‘Pedro Ximénez’, ‘Pinot Blanc’, ‘Pinot Gris’, ‘Sauvignon Blanc’, and ‘Tempranillo’; the minor cultivars ‘Chelva’, ‘Valencí Negre’, ‘Valencí Blanc’, and ‘Verdil’; and the endangered cv. ‘Esclafacherre’. Different growth rates were observed among cultivars: those with faster growth need to be subcultured every 1.5–2.0 months; those with the slowest growth every 3.5–4.0 months. The effect of halving the sucrose in MW reduced the growth of the cultivars that grew faster without compromising survival. When IBA was removed from MW, growth was also reduced in some cultivars. Therefore, small modifications of the MW composition are adequate for grapevine in vitro storage under standard incubation conditions. This is an advantage with respect to the change of temperature used in other work to achieve growth reduction, and allows the use of the same chamber for different in vitro culture procedures. 相似文献