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51.
J. B. Free Yvette Spencer-Booth 《The Journal of Horticultural Science and Biotechnology》2013,88(2):78-83
Individual bees tend to be constant to the type of food they are collecting from apple flowers, but most will alter their behaviour. This adaptability probably mostly accounts for changes in the ratio of nectar-gatherers to pollen-gatherers in orchards.Flowers of James Grieve and Cox’s Orange Pippin are equally attractive and bees readily change from one variety to the other ; flowers of Bramley’s Seedling are less attractive.During one foraging trip most bees probably visit the flowers along about 10 ft. only of a continuous row, and relatively few change from one row to another. To increase bee pollination, pollinizer trees should be at intervals of not more than 10 ft. in the same rows as trees of the main variety. 相似文献
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Harkin KR Roshto YM Sullivan JT Purvis TJ Chengappa MM 《Journal of the American Veterinary Medical Association》2003,222(9):1230-1233
OBJECTIVE: To compare results of polymerase chain reaction (PCR) testing of urine samples, serologic testing, and bacteriologic culture of urine to determine prevalence of urinary shedding of leptospires in dogs. DESIGN: Serial case study. ANIMALS: 500 dogs evaluated serially without regard to health status. PROCEDURE: Urine samples were examined via PCR assay and bacteriologic culture for leptospires. Blood samples were analyzed for antibodies against serovars canicola, bratislava, pomona, icterohemorrhagiae, grippotyphosa, and hardjo. RESULTS: Titers > or = 1:100 against at least 1 serovar were detected in 104 (20.8%) dogs, and titers > or = 1:400 were detected in 41 (8.2%) dogs. High titers were detected most commonly to serovar grippotyphosa, followed by icterohemorrhagiae, canicola, pomona, bratislava, and hardjo. High titers to > 1 serovar were detected in 14 dogs. A positive PCR assay result was obtained in 41 (8.2%) dogs, only 9 of which had a titer > or = 1:100. Leptospires were not cultured from the urine of any dog. Only 4 dogs had clinical leptospirosis. Overall disease prevalence was 0.8% for the 6-month evaluation period. Compared with PCR assay, serologic testing for predicting shedding had a sensitivity of 22%, specificity of 79%, positive predictive value of 9%, and negative predictive value of 92%. CONCLUSIONS AND CLINICAL RELEVANCE: Irrespective of health status, 8.2% of dogs were shedding pathogenic leptospires. Serologic testing was a poor predictor of urinary shedding. Clinically normal dogs that shed leptospires may pose a zoonotic risk to their owners. 相似文献
53.
Lamour J. Le Moguédec G. Naud O. Lechaudel M. Taylor J. Tisseyre Bruno 《Precision Agriculture》2021,22(3):873-896
Precision Agriculture - The use of data produced by farmers to generate knowledge and to inform production decisions is one of the objectives of precision agriculture (PA). Frameworks to analyse... 相似文献
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A 6-year-old, male, Collie-cross was presented with a non-weight bearing right thoracic limb lameness, right m. deltoideus, m. infraspinatus and m. supraspinatus atrophy, and severe neck pain with spasm of the cervical epaxial muscles. MRI revealed complete destruction of the 5th and 6th cervical vertebral bodies with lateral extradural spinal cord compression at the level of the 4th and 5th cervical vertebrae. These lesions were very clearly demonstrated on magnetic resonance images, while only subtle changes were seen on survey radiographs. Post mortem investigation revealed a large heart base chemodectoma with multiple smaller tumours in the cranial mediastinum and a single tumour nodule on the thoracic aorta. The 5th cervical vertebral body had necrotic, haemorrhagic and lytic changes. Histopathology of the heart base tumour, the nodules in the cranial mediastinum and on the thoracic aorta and samples from the 5th cervical vertebra confirmed the presence of a malignant aortic or carotid body tumour originating from the chemoreceptor organs. Diagnostic imaging features and post mortem findings are described. To our knowledge, this is the first report of the magnetic resonance features of a metastatic chemodectoma in a dog. 相似文献
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