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Méroc E Strubbe M Vangroenweghe F Czaplicki G Vermeersch K Hooyberghs J Van der Stede Y 《Preventive veterinary medicine》2012,105(4):309-314
Since July 2007, Belgium has implemented a national surveillance and control program for Salmonella in pigs. Pig farms are designated as Salmonella high risk farms based on serological profiles and are obliged to subsequently take part in a Salmonella specific action plan (SSAP). The SSAP was evaluated and potential risk factors for the persistence of Salmonella on the farm were investigated. First, the Kaplan-Meier method was used in order to study the period during which a farm maintains a Salmonella high risk status. Farms recovered more slowly from their high risk status before the SSAP was implemented compared to after the program was implemented (p<0.001). However, results showed that 29% of the farms were withdrawn from the program possibly only because of sampling error. The program should thus be adapted to accommodate for this. Secondly, the influence of several risk factors (type of farm, season of entrance into the SSAP, size of farm and farm density of the municipality) on the time to withdrawal from the high risk status was evaluated using univariable methods and a Cox multiple regression model for survival data. A statistically significant association was identified between the type of farm and the time to withdrawal from the high risk status. At any point in time after the onset of the SSAP, withdrawals from the high risk status occurred at a 39% and 28% higher rate in mixed (p=0.01) and fattening farms (p=0.05), respectively, compared to closed farms. The risk attributed to closed pig farms is related to the presence of sows in this particular type of structure, which underlines the importance of implementing control measures in this category of animals. 相似文献
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OBJECTIVES: Low-income households in the UK concentrate factors associated with poor record-keeping such as lower literacy, numeracy and English language skills. The present study aimed to (1) compare the validity and acceptability of three dietary survey methods against appropriate reference measures and (2) identify a method which was both valid and acceptable in low-income households. DESIGN: Cross-sectional design comparing three 4-day dietary survey methods (multiple-pass 24-hour recall, food checklist and semi-weighed method) against a 4-day weighed inventory and other reference measures within subjects. SETTING: London, UK, 2001. SUBJECTS: Low-income households were selected using a doorstep screening questionnaire in 18 of the 60 most deprived neighbourhoods in London. Results are based on 384 respondents (159 males, 225 females) aged 2-90 years in 240 households. Respondents were mainly White (48%), Black or Black British (31%) or Asian or Asian British (9%). RESULTS: The dietary survey method preferred by interviewers was the 24-hour recall. Most respondents preferred the food checklist. Compared with the weighed inventory, repeat 24-hour recalls and the food checklist yielded higher estimates of energy and nutrient intakes. The semi-weighed method was least liked and yielded the lowest estimates of intake. CONCLUSIONS: Based partly on evidence presented here and partly on evidence to be presented in later publications, four multiple-pass 24-hour recalls were recommended as the most appropriate method for a national study of diet and nutrition in low-income households in the UK. 相似文献
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Matthews NS Belz KM Fosgate GT Pappas C 《Veterinary therapeutics : research in applied veterinary medicine》2007,8(1):5-17
Medications given preoperatively have the potential to affect the induction dose of injectable anesthetics, which could result in an anesthetic overdose. Tepoxalin is an NSAID approved for the treatment of arthritis in dogs in the United States and hence could be administered in patients requiring anesthesia. In this study, administration of a single dose or a 10-day course of tepoxalin did not affect the induction dose (dose that allowed intubation) of propofol, thiopental, or ketamine-diazepam and also did not affect the time required for dogs to recover from anesthesia. 相似文献