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1.
The possibility of combining novel monitoring techniques and precision spraying for crop protection in the future is discussed. A generic model for an innovative crop protection system has been used as a framework. This system will be able to monitor the entire cropping system and identify the presence of relevant pests, diseases and weeds online, and will be location specific. The system will offer prevention, monitoring, interpretation and action which will be performed in a continuous way. The monitoring is divided into several parts. Planting material, seeds and soil should be monitored for prevention purposes before the growing period to avoid, for example, the introduction of disease into the field and to ensure optimal growth conditions. Data from previous growing seasons, such as the location of weeds and previous diseases, should also be included. During the growing season, the crop will be monitored at a macroscale level until a location that needs special attention is identified. If relevant, this area will be monitored more intensively at a microscale level. A decision engine will analyse the data and offer advice on how to control the detected diseases, pests and weeds, using precision spray techniques or alternative measures. The goal is to provide tools that are able to produce high-quality products with the minimal use of conventional plant protection products. This review describes the technologies that can be used or that need further development in order to achieve this goal.  相似文献   
2.
Gastrointestinal Lymphoma in 20 Dogs   总被引:1,自引:1,他引:0  
The records of 20 dogs with histopathologically diagnosed gastrointestinal (GI) lymphoma (LSA) evaluated between 1970 and 1984 were reviewed. Fifteen dogs were considered to have primary GI LSA, while five dogs had GI involvement in association with the multicentric form. Most clinical and laboratory findings were nonspecific, but positive-contrast upper GI radiography was suggestive of GI LSA in all of the dogs evaluated. Nine dogs had extensive lymphocytic-plasmacytic inflammatory infiltrates around the neoplastic foci, resulting in difficulty in obtaining a diagnosis of GI LSA when samples were obtained by endoscopy.  相似文献   
3.
Grazing by large ungulates has been chosen as a management tool in scrub-dominated dune reserves at the Belgian coast. Due to morphological and physiological differences between cattle and ponies, differences in foraging behaviour and habitat use are expected, and these may result in a different impact on the spatially heterogeneous and nutrient-limited ecosystem. Grazing behaviour and habitat use of Shetland ponies and Highland cattle, grazing together in a coastal dune area (60 ha) were investigated at various levels of the foraging hierarchy (habitat, vegetation type, sward height and diet). Habitat use overlap was high in all seasons; both cattle and pony spent most of their grazing time in the grass-dominated habitat. However, Shetland ponies concentrated their grazing activity more on the grass-dominated habitat than did cattle. Cattle spent a greater proportion of their grazing activity in woodland and scrub, compared to the ponies. Foraging activity in woodland and scrub is strongly influenced by season. Within the grass-dominated habitat both species preferred foraging in the grasslands and avoided open vegetation and moss dunes. Within the grasslands, cattle grazed less on the short swards than did ponies. Both cattle and ponies predominantly foraged on graminoids, though there are minor differences between both species and among seasons. Browsing of woody plants occurred only by cattle. Where grazing management has been implemented to maintain dune grasslands and to avoid further invasion by scrub, a combination of cattle and ponies appears to be adequate. Ponies are suitable for maintaining grasslands, but they have no impact on invading scrub. Cattle have an impact on scrub development, both by direct consumption of various shrub species and by opening initially closed scrub.  相似文献   
4.
饲料中的甘油一酸酯在母猪的胃肠道吸收后被转运到血液。在哺乳母猪中,这些甘油一酸酯随乳汁排出,并对新生仔猪具有有益的影响。尤其是加入母猪日粮中的甘油一丁酸酯和甘油一丙酸酯,已表明可以改善仔猪的健康和生产性能指标。  相似文献   
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6.
• AGD aims for a green environment, sustainable agriculture and clean water. • Presenting examples of the impact of agriculture on water quality. • Presenting examples of solutions for sustainable agriculture and improved water quality. • Integration of livestock and cropping systems is possible on a farm or among farms. • Providing recommendations for further development of sustainable agriculture. Crop and livestock production are essential to maintain food security. In China, crop and livestock production were integrated in the past. Today, small backyard systems are still integrated but the larger livestock farms are landless and largely geographically separated from crop production systems. As a result, there is less recycling of animal manures and there are lower nutrient use efficiencies in the Chinese food production systems. This, in turn, results in considerable losses of nutrients, causing water pollution and harmful algal blooms in Chinese lakes, rivers and seas. To turn the tide, there is a need for agricultural “green” development for food production through reintegrating crop and livestock production. An additional wish is to turn the Chinese water systems “blue” to secure clean water for current and future generations. In this paper, current knowledge is summarized to identify promising interventions for reintegrating crop and livestock production toward clean water. Technical, social, economic, policy and environmental interventions are addressed and examples are given. The paper highlights recommended next steps to achieve “green” agriculture and “blue” water in China.  相似文献   
7.
Complement factor H polymorphism and age-related macular degeneration   总被引:1,自引:0,他引:1  
Age-related macular degeneration (AMD) is a common, late-onset, and complex trait with multiple risk factors. Concentrating on a region harboring a locus for AMD on 1q25-31, the ARMD1 locus, we tested single-nucleotide polymorphisms for association with AMD in two independent case-control populations. Significant association (P = 4.95 x 10(-10)) was identified within the regulation of complement activation locus and was centered over a tyrosine-402 --> histidine-402 protein polymorphism in the gene encoding complement factor H. Possession of at least one histidine at amino acid position 402 increased the risk of AMD 2.7-fold and may account for 50% of the attributable risk of AMD.  相似文献   
8.
Ante mortem diagnosis of portal vein thrombosis was determined ultrasonographically in four dogs. In each dog the thrombus was visible in two-dimensional, grey-scale images of the portal vein obtained through a right intercostal window. Duplex-Doppler measurements and color-Doppler images provided information about the effects of thrombosis on portal blood flow. Reduced portal blood flow compatible with portal hypertension was detected in three dogs. A hypercoagulable state was probably involved in the pathogenesis of portal vein thrombosis in two dogs, one with pancreatitis and gastrointestinal blood loss and another with protein-losing nephropathy and probable immune-mediated anemia. The third dog had chronic ehrlichiosis; thrombosis was probably secondary to vasculitis. The remaining dog had thrombosis secondary to invasion of the portal vein by a recurrent duodenal neoplasm. This dog was euthanized because the tumor was considered inoperable. The dog with pancreatitis developed acute portal hypertension due to obstruction of the portal vein by the thrombus and was euthanized. The dogs with protein-losing nephropathy and ehrlichiosis were treated medically and recovered. Although portal vein thrombosis is uncommon, this complication should be considered in dogs with a variety of abdominal or systemic disorders. Ultrasonography is a practical method for diagnosis of portal vein thrombosis and detection of the underlying cause.  相似文献   
9.
A good horse-rider 'match' is important in the context of equine welfare. To quantify the influence of repetition and horse-rider matching on the stress of horses encountering challenging objects, 16 Warmblood horses were ridden in a test-setting on three occasions. On each occasion the horse was ridden by a different rider and was challenged by three objects (A-C). Heart rate (HR), heart rate variability (HRV) of horse and rider, and behaviour score (BS) of the horse were obtained for each object and as a total for each test. The horse-rider interaction was evaluated with each combination and assessed as 'matching' or 'mismatching', and the horses were categorised as 'compliant', 'partly-compliant' or 'non-compliant'. Horses exhibited a decreased HR (P=0.015) and a decreased BS (P=0.004) within and across different tests. 'Matching' horse-rider combinations exhibited less stress as indicated by reduced HR ('match' 69±10 vs. 'mismatch' 72±9, P=0.001) and BS ('match' 1.9±1.1 vs. 'mismatch' 3.8±1.4, P=0.017) of the horse. 'Compliant' (68±8, P<0.001) and 'partly-compliant' (71±9, P=0.002) horses had significantly lower HR than 'non-compliant' (75±9) animals. The findings of the study indicate that HR and BS measurements support a subjective 'match' diagnosis and HR measurement may be a valuable tool in assessing horse compliance.  相似文献   
10.
The cereal root-knot nematode Meloidogyne naasi can cause serious cereal crop losses. The nematode is also found in agricultural fields where non-host crops are grown. Control of M. naasi can be based on preventing its spread, host resistance and crop management as well as on the design of crop rotation systems. Detection methods are required for these purposes and can also be helpful for inspection services and experimental research. This study describes the development of a simple PCR test that enables the detection of M. naasi. Alignment of sequences of rDNA-ITS fragments of M. naasi and five other Meloidogyne species was used to design the M. naasi specific forward primer N-ITS. Together with the reverse primer R195 M. naasi specific amplification was achieved.  相似文献   
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