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排序方式: 共有80条查询结果,搜索用时 31 毫秒
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Around 20,000 samples are analysed each year for the presence of antibacterial residues in Danish finisher pigs, and between zero and five samples are detected positive above the maximum residue level (MRL). The intention was to develop a risk-based surveillance programme involving fewer samples while ensuring equal sensitivity. Therefore, risk indicators were searched for. Data were obtained from the Danish slaughterhouse database covering the period from July 2010 to December 2012. Residues were found or suspected in 17 incidents. In nine of these, the farmer had called in to prevent the pigs from being slaughtered. Hence, eight suspect cases were found through the surveillance programme, and two of these were above MRL. For these eight case herds, the number of pigs slaughtered and the number in which each of the following lesions were found were included in a statistical analysis: chronic pleuritis, tail bite, chronic pericarditis, chronic pneumonia, chronic peritonitis, osteomyelitis, abscess in hindquarters, abscess in leg/toe and abscess in forequarters. Only chronic pleuritis was associated with the presence of residues. Next, data from all herds delivering pigs for slaughter to the same abattoir were included covering a 3-month period prior to the residue finding. The prevalence of chronic pleuritis was on average 1.7 times higher in the eight case herds compared to all other herds. In two herds, the prevalence was significantly higher (P ≤ 0.05), and in one herd substantially higher, but only borderline significant (P = 0.1). In the remaining herds, the prevalence did not differ from the other herds delivering pigs to the abattoir. This indicates that chronic pleuritis might be considered as a risk indicator for use in surveillance. Other risk indicators/factors – reported in the cases where the farmers called in – were inadequate marking of treated animals and incorrect use of medication dispensers. These factors are not suited for use in surveillance and should be dealt with otherwise. 相似文献
3.
Bockelée-Morvan D Biver N Moreno R Colom P Crovisier J Gérard E Henry F Lis DC Matthews H Weaver HA Womack M Festou MC 《Science (New York, N.Y.)》2001,292(5520):1339-1343
The gas activity of comet C/1999 S4 (LINEAR) was monitored at radio wavelengths during its disruption. A runaway fragmentation of the nucleus may have begun around 18 July 2000 and proceeded until 23 July. The mass in small icy debris (=30-centimeter radius) was comparable to the mass in the large fragments seen in optical images. The mass budget after breakup suggests a small nucleus ( approximately 100- to 300-meter radius) that had been losing debris for weeks. The HNC, H2CO, H2S, and CS abundances relative to H2O measured during breakup are consistent with those obtained in other comets. However, a deficiency in CH3OH and CO is observed. 相似文献
4.
Structure of a legume lectin with an ordered N-linked carbohydrate in complex with lactose 总被引:13,自引:0,他引:13
The three-dimensional structure of the lactose complex of the Erythrina corallodendron lectin (EcorL), a dimer of N-glycosylated subunits, was determined crystallographically and refined at 2.0 angstrom resolution to an R value of 0.19. The tertiary structure of the subunit is similar to that of other legume lectins, but interference by the bulky N-linked heptasaccharide, which is exceptionally well ordered in the crystal, forces the EcorL dimer into a drastically different quaternary structure. Only the galactose moiety of the lactose ligand resides within the combining site. The galactose moiety is oriented differently from ligands in the mannose-glucose specific legume lectins and is held by hydrophobic interactions with Ala88, Tyr106, Phe131, and Ala218 and by seven hydrogen bonds, four of which are to the conserved Asp89, Asn133, and NH of Gly107. The specificity of legume lectins toward the different C-4 epimers appears to be associated with extensive variations in the outline of the variable parts of the binding sites. 相似文献
5.
Recent work has shown that the RNA polymerase II enzyme pauses at a promoter-proximal site of many genes in Drosophila and mammals. This rate-limiting step occurs after recruitment and initiation of RNA polymerase II at a gene promoter. This stage in early elongation appears to be an important and broadly used target of gene regulation. 相似文献
6.
The aim of this study was to determine the effect of fish-based feed materials, as a source of readily available protein contained in fish broth and essential polyunsaturated fatty acids (PUFAs) found in fish oil, on the health of piglets and rearing results. The experiment was conducted on a commercial pig fattening farm. The study involved a total of 80 weaners with an approximate body weight of 15 kg. The experiment was carried out over a period of 40 days. Feed samples were subjected to laboratory analyses. Blood samples were collected from experimental group animals to determine serum biochemical and immunological parameters. The body weight gains of weaners, mortality rates and average feed intake per animal were calculated for the entire experimental period. The addition of fish broth and fish oil significantly improved the n3:n6 fatty acid ratio in diets. The presence of EPA and DHA in the experimental diet could have had a positive health effect on piglets, comparable with that exerted by therapeutic doses of zinc often administered to pigs of this age group. During the experiment, feed conversion ratio (FCR) gain was considerably reduced in the experimental group, with similar daily gains in the control and experimental group. 相似文献
7.
The prevalence of Coxiella burnetii and Chlamydia psittaci antibodies was investigated in 530 dog specimens divided into six groups, i. e. A = private watch dogs, B1 = service dogs from Bratislava, B2 = service dogs from other localities of Slovakia and Moravia, C = watch dogs from farms, I = household dogs, T = stray dogs. The dogs demonstrated the higher seropositivity to C. burnetii (11.7%) than to Ch. psittaci (5.5%). The highest percentage of antibodies to C. burnetii was found in stray dogs (23.7%), less prevalence of antibodies was observed in the animals in group C (13.6%), almost the same positivity was proved in the dogs of group B1 and B2 (10.5 and 10.6%). The highest positivity to Ch. psittaci was demonstrated in the dogs of group A (8.7%), less in group B2 (6.6%) and the least number in group B1 (1.9%). The stray dogs occupied the intermediate position in this data (Tab. I). Ninety four localities were tested, from which 38 were seropositive. Neither acute coxiellosis nor chlamydiosis were proved in any animals examined. Ninety per cent of dogs were found healthy, but 10% of dogs demonstrated hepatopathia and gastroenteritis. Two of them (category A and I) were seropositive to C. burnetii (titer 1:8 to 1:16) and one to Ch. psittaci (titer 1:16). Both C. burnetii and Ch. psittaci attack dogs parallely with the agents of other zoonoses, of which the most common is Toxoplasma gondii (Tab. II). Several dogs demonstrated seropositivity to three up to five zoonotic agents (Tab. III). 相似文献
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9.
Kenji Sato Paul C Bartlett Lis Alban Jens F Agger Hans Houe 《Acta veterinaria Scandinavica》2008,50(1):4
Background
Several management and environmental factors are known as contributory causes of clinical mastitis in dairy herd. The study objectives were to describe the structure of herd-specific mastitis management and environmental factors and to assess the relevance of these herd-specific indicators to mastitis incidence rate.Methods
Disease reports from the Danish Cattle Data Base and a management questionnaire from 2,146 herds in three Danish regions were analyzed to identify and characterize risk factors of clinical mastitis. A total of 94 (18 continuous and 76 discrete) management and production variables were screened in separate bivariate regression models. Variables associated with mastitis incidence rate at a p-value < 0.10 were examined with a factor analysis to assess the construct of data. Separately, a multivariable regression model was used to estimate the association of management variables with herd mastitis rate.Results
Three latent factors (quality of labor, region of Denmark and claw trimming, and quality of outdoor holding area) were identified from 14 variables. Daily milk production per cow, claw disease, quality of labor and region of Denmark were found to be significantly associated with mastitis incidence rate. A common multiple regression analysis with backward and forward selection procedures indicated there were 9 herd-specific risk factors.Conclusion
Though risk factors ascertained by farmer-completed surveys explained a small percentage of the among-herd variability in crude herd-specific mastitis rates, the study suggested that farmer attitudes toward mastitis and lameness treatment were important determinants for mastitis incidence rate. Our factor analysis identified one significant latent factor, which was related to labor quality on the farm. 相似文献10.
Alban L Boes J Kreiner H Petersen JV Willeberg P 《Preventive veterinary medicine》2008,87(3-4):340-357
Increasing demands for cost-effectiveness in surveillance for human health hazards from animal origins can be met by introducing risk-based principles. This e.g. implies targeting subpopulations with higher risk of infection compared to the whole population. Furthermore, historical data from surveillance can be collated and used to assess future risk of infection. To demonstrate the effectiveness of combining these two approaches, we used a model called “Discounting historical evidence”. It depends mainly on the annual risk of introduction (PIntro) and the surveillance system sensitivity (SSe) (ability to detect infection if present). The model implies simulations that reiterate for a number of years. For each year the output is updated with the confidence on absence in infection. Trichinella spiralis infection in pigs is used as an example. In Denmark, more than 20 million pigs are tested annually. Despite more than 70 years of testing no pigs have been found positive for Trichinella. Hence, PIntro is low. SSe can be estimated from the maximum number of infected carcasses expected under the specified design prevalence, and the sensitivity of the test applied. According to our assessment, the current prevalence of Trichinella in Danish pigs is less than one case per million, which we interpret as negligible risk. Based on this, a risk-based surveillance programme for Trichinella is designed that targets all out-door reared pigs as well as all sows and boars (current total 610,000 slaughtered annually). These subpopulations are judged to have higher risk of getting Trichinella. Again, SSe and PIntro are estimated and the model results show that risk-based surveillance can be applied without jeopardizing human health. Finally, we incorporate wildlife surveys and test quality assurance in the programme. The results of the simulation model were included in an application to the European Commission concerning Denmark's status as a region with negligible risk of Trichinella. In July 2007, the European Commission granted status as “negligible risk” to Danish pigs and pork. 相似文献