2 resultados para adjustable moment and rotation speed

em DigitalCommons@University of Nebraska - Lincoln


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Livestock face complex foraging options associated with optimizing nutrient intake while being able to avoid areas posing risk of parasites or disease. Areas of tall nutrient-rich swards around fecal deposits may be attractive for grazing, but might incur fitness costs from parasites. We use the example of dairy cattle and the risks of tuberculosis transmission posed to them by pastures contaminated with badger excreta to examine this trade-off. A risk may be posed either by aerosolized inhalation through investigation or by ingestion via grazing contaminated swards. We quantified the levels of investigation and grazing of 150 dairy cows at badger latrines (accumulations of feces and urine) and crossing points (urination-only sites). Grazing behavior was compared between strip-grazed and rotation-grazed fields. Strip grazing had fields subdivided for grazing periods of <24 h, whereas rotational grazing involved access to whole fields for 1 to 7 d each. A higher proportion of the herd investigated badger latrines than crossing points or controls. Cattle initially avoided swards around badger latrines but not around crossing points. Avoidance periods were shorter in strip- compared with rotation-grazing systems. In rotation-grazing management, latrines were avoided for longer times, but there were more investigative contacts than with strip-grazing management. If investigation is a major route of tuberculosis transmission, the risk to cattle is greatest in extensive rotation-grazing systems. However, if ingestion of fresh urine is the primary method of transmission, strip-grazing management may pose a greater threat. Farming systems affect the level and type of contact between livestock and wildlife excreta and thus the risks of disease.

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This study examines the use of Cybercafés/Internet resources and the evaluation of their usefulness. About eight Cybercafés located in the university community were used in this study. Questionnaires, interviews with the Cybercafé owners, staff and users as well as personal observations made during inspection of these cafés were used in this study. The data were analysed according to the background of the Internet users. The richness and high speed, accuracy, and authority were used by users to judge the quality of the Internet. Information such as the establishment of the café's facilities, membership and the future of the Cybercafés were also looked into. Finally, one can clearly see that the dominating impact of digital technology has crossed the Rubicon of controversy. The result of the survey shows that forty percent of the users learnt to use the internet by self instruction, thirty five percent learnt from colleagues or friends. Those in the sciences use the internet the most, the channel mostly used in obtaining information is the search engines. A large number of students, faculties and researchers make use of the internet in obtaining information. Many of those of those users make use of the Cybercafés in the university community.