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81.
A wild tetraploid oat Avena maroccana Gdgr. was collected from the 11 populations in the periphery of Rommani and Casablanca geographic groups of Morocco. Genetic
diversity of the species was investigated using six allozyme systems. Allelic frequencies were scored representing eight polymorphic
and five monomorphic loci. Coefficient of gene differentiation (Gst) was 0.3019, which indicated great genetic differentiation. The number of alleles per locus was 2.6154, the percentage of
polymorphic loci was 61.54, and the expected heterozygosity was 0.2462 in all populations. Genetic diversity in A. maroccana was high in comparison to self-pollinated species. In total, nine heterozygotes resulting from outcrossing were found in
the progeny from M1, M3, M4, M22 and M26. The population of M7 had peculiar alleles Pgd–2SS and Pgd-1SS in high frequency. M9 had the lowest level of diversity out of the 11 populations. Geographic and genetic distances between
all the populations were not significantly correlated with each other (r = 0.0996). Cluster analysis showed that two groups, (M1, M22, M2 and M4) and (M3, M23, M8, M5 and M26) were apparently differentiated.
Two populations of the Casablanca group, M7 and M9 were independent from each other, and were separated distinctly from the
other populations. Genetic diversity of the Rommani and Casablanca groups was almost the same in all the parameters. This
was due to the similar man-made habitat such as roadside or rich fertile soil and brown clay soils. The population size of
A. maroccana was small and restricted to the narrow central Morocco with great genetic differentiation so that genetic diversity may be
reflected from the results of genetic drift and outcrossing heterozygote segregation. 相似文献
82.
Herdt TH Neuder LM Green CD Fordyce MG Dill KJ Mahoney JH 《Journal of veterinary medical education》2008,35(1):48-50
Cooperative programs with agribusiness offer opportunities for colleges of veterinary medicine to expand their instructional programs in agricultural practice. Agribusinesses associated with livestock agriculture recognize the importance of veterinary medicine in maintaining a vibrant and successful industry. Stewardship of corporate support involves close communication with advocates within the companies, providing them with documentation of the potential effects of corporate investments. This article describes the creation of the Michigan State University (MSU) Training Center for Dairy Professionals, a key aspect of which was the identification of innovative and productive areas of mutual interest and benefit. In addition to supporting the dairy industry by training veterinary students, the program offers specific benefits to investors, including the use of MSU facilities and direct participation in veterinary instruction. 相似文献
83.
84.
Allison GG Stevens PR Heasman L Davis AM Jackman R Moorby JM 《Veterinary research communications》2008,32(8):591-597
Three groups of two weeks old growing lambs differing in PrP genotype were orally inoculated with scrapie and maintained under
defined conditions until disease endpoint. Plasma concentrations of free alanine and serine, but not L-lactate increased during
the final 6 months of the disease. At the same time, plasma concentrations of several essential and non-essential free amino
acids decreased linearly, indicating reduced feed intake and are consistent with, but occurring before establishment, of cachexia.
These observations are consistent with those reported previously from studies on cattle infected with BSE and with the hypothesis
that scrapie may effect peripheral tissue metabolism. 相似文献
85.
86.
Leslie W Woods Howard D Lehmkuhl Lea Ann Hobbs Jackie C Parker Mike Manzer 《Journal of veterinary diagnostic investigation》2008,20(1):33-37
Four 3-month-old Jersey calves and three 3-month-old Holstein calves were inoculated with cervid adenovirus and monitored for clinical signs until necropsied between 10 and 42 days postinoculation. The neonatal Jersey calves had received colostrum, and the Holstein calves were colostrum deprived. Preinoculation and postinoculation serum samples were tested for antibodies to the cervid adenovirus, bovine adenovirus type 6, bovine adenovirus type 7, and goat adenovirus type 1. Virus isolation was performed on kidney, nasal secretion, and/or lung homogenates in fetal white-tailed deer lung cells. Negatively stained preparations of feces from Jersey calves were examined weekly using an electron microscope, and weekly blood samples were collected for complete blood counts. Full necropsies were performed on all calves. A complete selection of tissues was evaluated for microscopic changes, and immunohistochemistry was performed on all tissues using a polyclonal antibody to deer adenovirus. No clinical signs were observed in the calves during the study period. Following inoculation, colostrum-deprived calves developed low antibody titers to deer adenovirus, while the Jersey calves that received colostrum did not. Calves that received colostrum had high antibody titers to bovine adenovirus type 7 and goat adenovirus type 1. No consistent gross or microscopic lesions were seen. Adenovirus was not observed in negatively stained preparations of feces. Immunohistochemistry results did not demonstrate virus in all tissues examined microscopically, and virus was not isolated from lungs, nasal secretions, and kidneys. 相似文献
87.
Mike P. Targett MA VetMB PhD MRCVS Elizabeth McInnes BVSc PhD MRC MRCVS Ruth Dennis MA VetMB DVR MRCVS 《Veterinary radiology & ultrasound》1999,40(1):23-26
Magnetic resonance images were acquired of the brain of a 7-year-old male Golden Retriever with hydrocephalus secondary to a medullary lesion. Images were acquired prior to and 4 weeks following surgical treatment for the hydrocephalus, and the dog was euthanased following the second imaging session. The MR images demonstrated a medullary lesion with patchy but predominantly hyperintense signal with both T1- and T2-weighting, within which small areas of low signal were scattered. There was little edema associated with this lesion and no enhancement with gadolinium. Postmortem examination revealed the medullary mass to be a dermoid cyst. Several small nodular lesions were identified within the central nervous system on the magnetic resonance images whose origin was uncertain on postmortem examination. 相似文献
88.
89.
Mike Bonell 《Irrigation and Drainage Systems》2010,24(3-4):279-325
Within the framework of IWRM, a major concern in the humid tropics is the effects of ‘global warming’ on the storm rainfall-runoff hydrology of both forests and converted forest lands. Further how such effects need to be incorporated within adaptive, forest-water-land management. But since the mid- 20th century, dramatic changes in land- use (LU) and land cover (LC) have also occurred which have led to rapid rates of deforestation and an expansion of land—forest degradation. How much these man-induced impacts have been influential on climate –water relations, as against the effects of inherent climate variability and predicted climate change scenarios, still remains a major challenge to quantify. Thus embedded within the global warming issue are these additional LU/LC change impacts on climate-rainfall-storm runoff across scales which also require consideration under the broader mandate of ‘global change’. The work will initially succinctly summarize the existing uncertainties linked with both Global Climate Models (GCMs). Subsequently more detailed attention will be given to uncertainties linked with LC/LU change. The experiences of hurricane Mitch in Central America will then set the scene for an alternative strategy. A principle message is a call for more concentrated research effort on geographically the outer margins of the ‘maritime continent’ (centred on the Indonesian Archipelago) in the Western Pacific where tropical cyclone frequency is very high. This region presents a diversity of socio-economies and an opportunity to produce adapted forest-land management measures in preparation for future global change (warming and anthropogenic). Such measures can then be extrapolated to currently less frequently, affected areas from extreme events like hurricane Mitch. Examples from research in the tropical- cyclone prone, “Wet Tropics” of northeast Australia linked with the management of tropical rainforests and the adjoining sugar cane lands are then used to demonstrate these opportunities. 相似文献
90.
Yu Zhang Beth A Lorsbach Scott Castetter William T Lambert Jeremy Kister Nick X Wang Carla J R Klittich Joshua Roth Thomas C Sparks Mike R Loso 《Pest management science》2018,74(9):1979-1991
The relentless need for the discovery and development of new agrochemicals continues as a result of driving forces such as loss of existing products through the development of resistance, the necessity for products with more favorable environmental and toxicological profiles, shifting pest spectra, and the changing agricultural needs and practices of the farming community. These new challenges underscore the demand for novel, high‐quality starting points to accelerate the discovery of new agrochemicals that address market challenges. This article discusses the efforts to identify the optimum ranges of physicochemical properties of agrochemicals through analysis of modern commercial products. Specifically, we reviewed literature studies examining physicochemical property effects and analyzed the properties typical of successful fungicides, herbicides, and insecticides (chewing and sap‐feeding pests). From the analysis, a new set of physicochemical property guidelines for each discipline, as well as building block class, are proposed. These new guidelines should significantly aid in the discovery of next‐generation agrochemicals. © 2018 Society of Chemical Industry 相似文献