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51.
During the past century, reductions in animal diseases have resulted in a safer, more uniform, and more economical food supply. In the United States, the passage of the 1906 Federal Meat Inspection Act mandated better sanitary conditions for slaughter and processing, as well as inspection of live animals and their processed products. Following World War II, Congress passed the Poultry Products Inspection Act. Both acts are regulated by the Food Safety and Inspection Service (FSIS) of the US Department of Agriculture (USDA). The USDA's Animal and Plant Health Inspection Service (APHIS) is responsible for regulations governing the health of live animals prior to slaughter. This article is a brief overview of the ways in which the current predominance of zoonotics among emerging diseases underscores the importance of veterinary health professionals and the need for continued coordination between animal-health and public-health officials. Examples of intersections between animal- and public-health concerns include bovine spongiform encephalopathy (BSE) and Johne's disease, as well as extending beyond food safety to diseases such as avian influenza (AI). In the United States, we have in place an extensive public and private infrastructure to address animal-health issues, including the necessary expertise and resources to address animal-health emergencies. However, many challenges remain, including a critical shortage of food-animal veterinarians. These challenges can be met by recruiting and training a cadre of additional food-supply veterinarians, pursuing new technologies, collaborating with public-health officials to create solutions, and sending a clear and consistent message to the public about important animal-health issues. 相似文献
52.
Hörz F Bastien R Borg J Bradley JP Bridges JC Brownlee DE Burchell MJ Chi M Cintala MJ Dai ZR Djouadi Z Dominguez G Economou TE Fairey SA Floss C Franchi IA Graham GA Green SF Heck P Hoppe P Huth J Ishii H Kearsley AT Kissel J Leitner J Leroux H Marhas K Messenger K Schwandt CS See TH Snead C Stadermann FJ Stephan T Stroud R Teslich N Trigo-Rodríguez JM Tuzzolino AJ Troadec D Tsou P Warren J Westphal A Wozniakiewicz P Wright I Zinner E 《Science (New York, N.Y.)》2006,314(5806):1716-1719
Particles emanating from comet 81P/Wild 2 collided with the Stardust spacecraft at 6.1 kilometers per second, producing hypervelocity impact features on the collector surfaces that were returned to Earth. The morphologies of these surprisingly diverse features were created by particles varying from dense mineral grains to loosely bound, polymineralic aggregates ranging from tens of nanometers to hundreds of micrometers in size. The cumulative size distribution of Wild 2 dust is shallower than that of comet Halley, yet steeper than that of comet Grigg-Skjellerup. 相似文献
53.
Time-resolved sum-frequency vibrational spectroscopy permits the study of hitherto neglected ultrafast vibrational dynamics of neat water interfaces. Measurements on interfacial bonded OH stretch modes revealed relaxation behavior on sub-picosecond time scales in close resemblance to that of bulk water. Vibrational excitation is followed by spectral diffusion, vibrational relaxation, and thermalization in the hydrogen-bonding network. Dephasing of the excitation occurs in =100 femtoseconds. Population relaxation of the dangling OH stretch was found to have a time constant of 1.3 picoseconds, the same as that for excitation transfer between hydrogen-bonded and unbonded OH stretches of water molecules surrounded by acetone. 相似文献
54.
Metabolic engineering of plants can reduce the cost and environmental impact of agriculture while providing for the needs of a growing population. Although our understanding of plant metabolism continues to increase at a rapid pace, relatively few plant metabolic engineering projects with commercial potential have emerged, in part because of a lack of principles for the rational manipulation of plant phenotype. One underexplored approach to identifying such design principles derives from analysis of the dominant constraints on plant fitness, and the evolutionary innovations in response to those constraints, that gave rise to the enormous diversity of natural plant metabolic pathways. 相似文献
55.
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57.
Ron A. Miller Francis R. Pelsor Andrew S. Kane Renate Reimschuessel 《Journal of aquatic animal health》2013,25(2):121-128
Abstract The pharmacokinetic–pharmacodynamic predictor of antimicrobial activity for tetracyclines is reported to be the area under the concentration–time curve at steady state (AUCss) divided by the minimal inhibitory concentration of the targeted pathogen. Here, we estimate AUCss values for oxytetracycline (OTC) in serum of rainbow trout Oncorhynchus mykiss by using a destructive sampling study design. Seventy-two rainbow trout were fed OTC-medicated feed at 74.7 ± 1.5 mg/kg (mean ± SD) body weight (BW) by oral gavage for 10 consecutive days. Serum was collected from nine fish at 1, 3, 6, 8, 10, 12, 15, and 22 d after dosing began. Serum OTC concentrations were measured by high-performance liquid chromatography with a 0.01-μg/mL limit of detection. The average OTC AUCss was 29.2 μg × h/mL and was estimated using nonlinear mixed-effects modeling and bootstrap resampling techniques. The elimination half-life was estimated as 85.0 h, and the fraction of steady state achieved was estimated as 0.85. The calculated AUCss (24.8 μg × h/mL) following 10 d of oral dosing with 75 mg OTC/kg BW was less than the estimated AUCss. Results suggest that the pharmacokinetics of OTC exposure, including the AUCss, is better evaluated by using multiday dosimetry than by using a standard single-dose protocol. Received September 29, 2011; accepted January 30, 2012 相似文献
58.
Streptobacillus moniliformis is a zoonotic bacterium. We obtained positive S. moniliformis PCR results in oral swab samples from guinea pigs from an experimental colony and the breeding colony of origin. Comparison of the DNA sequence of an amplicon with deposited 16S rDNA sequences revealed that Leptotrichia sp. can be the source of a false positive S. moniliformis PCR outcome. 相似文献
59.
光对家禽非常重要。家禽不仅需要光的帮助来寻找饲料、水、产蛋窝,而且生殖系统也受到光的控制。为了掌握其机理,我们从光和家禽两方面来做介绍。 相似文献
60.
Takken W Verhulst N Scholte EJ Jacobs F Jongema Y van Lammeren R 《Preventive veterinary medicine》2008,87(1-2):41-54
The Netherlands has enjoyed a relatively free state of vector-borne diseases of economic importance for more than one century. Emerging infectious diseases may change this situation, threatening the health of humans, domestic livestock and wildlife. In order to be prepared for the potential outbreak of vector-borne diseases, a study was undertaken to investigate the distribution and seasonal dynamics of candidate vectors of infectious diseases with emphasis on bluetongue vectors (Culicoides spp.). The study focused primarily on the relationship between characteristic ecosystems suitable for bluetongue vectors and climate, as well as on the phenology and population dynamics of these vectors. Twelve locations were selected, distributed over four distinct habitats: a wetland area, three riverine systems, four peat land areas and four livestock farms. Culicoides populations were sampled continuously using CO(2)-baited counterflow traps from July 2005 until August 2006, with an interruption from November 2005 to March 2006. All vectors were identified to species level. Meteorological and environmental data were collected at each location. Culicoides species were found in all four different habitat types studied. Wetland areas and peat bogs were rich in Culicoides spp. The taxonomic groups Culicoides obsoletus (Meigen) and Culicoides pulicaris (Linnaeus) were strongly associated with farms. Eighty-eight percent of all Culicoides consisted of the taxon C. obsoletus/Culicoides scoticus. On the livestock farms, 3% of Culicoides existed of the alleged bluetongue vector Culicoides dewulfi Goetghebuer. Culicoides impunctatus Goetghebuer was strongly associated with wetland and peat bog. Many Culicoides species were found until late in the phenological season and their activity was strongly associated with climate throughout the year. High annual variations in population dynamics were observed within the same study areas, which were probably caused by annual variations in environmental conditions. The study demonstrates that candidate vectors of bluetongue virus are present in natural and livestock-farm habitats in the Netherlands, distributed widely across the country. Under favourable climatic conditions, following virus introduction, bluetongue can spread among livestock (cattle, sheep and goats), depending on the nature of the viral serotype. The question now arises whether the virus can survive the winter conditions in north-western Europe and whether measures can be taken that effectively halt further spread of the disease. 相似文献