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1.
世界上许多国家都准许在饲料中采用亚治疗量的抗生素作为生长促进剂。然而 ,这种做法正在受到越来越严厉的责问 ,因为这种做法有可能将抗药性传递给人类的病原菌。欧盟各国当前禁用了大多数这类抗生素 ,并且看来会在不久的将来完全禁用非处方饲用抗生素。所以人们一直在搜寻有效的饲用抗生素替代物。促生长抗生素和生菌剂各自都能以其独特的方式改变肠道微生物群体的组成并且减少病原菌的数量 (Lindsey ,1992 )。抗生素生长促进剂能减少肠道菌总数 ,包括格兰氏阴性病原菌。生菌剂则向机体提供芽孢杆菌、乳杆菌、链球菌、拟杆菌、酵母和霉菌…  相似文献   
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The clinical documentation of enteropathogenic bacteria causing diarrhea in dogs is clouded by the presence of many of these organisms existing as normal constituents of the indigenous intestinal flora. The diagnosis of a putative bacterial enteropathogen(s) in dogs should be made based on a combination of parameters, including signalment and predisposing factors, clinical signs, serologic assays for toxins, fecal culture, and PCR. Relying on results of fecal culture alone is problematic, because C perfringens, C difficile, Campylobacter spp, and pathogenic and non-pathogenic E coli are commonly isolated from apparently healthy dogs [10,13,33]. Nevertheless, culture may be useful in procuring isolates for the application of molecular techniques, such as PCR, for detection of specific toxin genes or molecular typing of isolated strains to establish clonality in suspected outbreaks. The oversimplistic attempt to characterize bacterially associated diarrhea by anatomic localization of clinical signs should be discouraged, because most of the previously mentioned bacteria have been associated with small and large intestinal diarrhea. Accurate diagnosis of infections may require diagnostic laboratories to incorporate PCR-based assays using genus- and species-specific primers to facilitate detection of toxin genes and differentiation of species that appear phenotypically and biochemically similar. There has been tremendous interest in the application of microarray technology for the simultaneous detection of thousands of genes or target DNA sequences on one glass slide. This powerful tool could be used for detection of specific pathogenic bacterial strains in fecal specimens obtained from dogs in the future.  相似文献   
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1. The influence of aflatoxin on growth and mortality of diverse lines of quail was studied in five trials.

2. Feeding 5 or 10 /μg aflatoxin/g diet from 4 to 7 weeks of age resulted in significant decreases in body‐weight gain in all lines.

3. Similar gains for all treatments during the third week of feeding indicated that body weights were reduced only during the first two weeks.

4. Crop intubation with 4 or 8 mg aflatoxin/kg body weight resulted in different mortality patterns for the selected and control quail lines.  相似文献   

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Olive mill waste (OMW) contains substantial amounts of valuable antioxidant biophenols that can be recovered for possible applications in food, pharmaceutical, and cosmetic industries. However, the impact of cultivar, harvesting time, and seasonal variation on the phenolic composition of OMW has not yet been assessed. Total phenols, antioxidant activity, and phenol profiles of OMW extracts from five different Australian-grown cultivars (Barnea, Correggiola, Manzanillo, Mission, and Paragon) were studied at four different harvesting times in the 2004 season. The impact of seasonal variation was assessed by comparing total phenol content, antioxidant activity, and phenol profile of two cultivars (Correggiola and Mission) harvested in the 2004 and 2005 seasons. The phenol content and antioxidant activity at different harvesting times were mainly a function of the olive cultivar. Harvesting time had a quantitative effect rather than a qualitative effect on the phenol profile. Intercultivar and harvesting time variation accounted for a 2-5-fold change in the total phenol and antioxidant capacity, while levels of individual biophenols experienced up to 50-fold change. The phenol content and antioxidant capacity of OMW significantly changed between seasons with different variation patterns for different cultivars.  相似文献   
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Vigorous and prolonged effort is required to gain true mastery of the healing arts. Conventional and complementary medicine have complementary strengths and weaknesses. Like the yin and yang of traditional Chinese medicine, they naturally flow into one another by a process of induction, creating balance. Integrative medicine is the frontier; it is the future. If we are to progress beyond our current understanding and ability to heal, we must work with theoretic models that allow us and our perception to operate "outside the box." For some, this understanding is intuitive. It is through cooperative and collaborative efforts of intuitively adept and technologically adept minds that we can integrate and advance our understanding; increase our ability to predict, prevent, and diagnose disease; and expand our therapeutic options.  相似文献   
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Medullary trichomalacia is the name proposed for a hair shaft abnormality that was recognized in 6 German shepherd dogs. Affected dogs had multifocal areas of broken hairs, especially on the dorsolateral trunk. Microscopic examination of hair shafts revealed focal areas of loss of architecture, swelling, and apparent softening of the medulla, followed by longitudinal (length-wise) splitting and breakage of the hair shaft. No cause could be found. Affected dogs were otherwise healthy, and apparent spontaneous recovery was the usual outcome. Relapses may occur.  相似文献   
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