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1.
In the period December 1967 through April 1969 eight spontaneous cases of pseudorabies in Danish red foxes were demonstrated by virus isolation. One fox had been kept in captivity, the remaining seven were free-living. Five of the foxes were found dead, while three, presenting abnormal behaviour when encountered, had been killed.  相似文献   
2.

Background

Repeat patient testing‐based quality control (RPT‐QC) is a potential method for veterinary laboratories (eg, that have a limited budget for quality commercial control material [QCM] or that wish to use material with a species‐specific matrix).

Objectives

To determine whether total error (TEa), probability of error detection (Ped), and probability of false rejection (Pfr) similar to that achievable with QC materials can be controlled using RPT‐QC

Methods

Control limits (WBC, RBC, HGB, HCT, MCV, and PLT) for the Advia 120 (n = 23) and scil Vet ABC (n = 22) were calculated using data from normal canine specimens from a routine caseload. Specimens were measured at accession and again after 24 hours. Control limits were validated using 23 additional canine specimens tested similarly. Achievable TEa, Ped, and Pfr were investigated using the Westgard EZRules3 and compared to those achievable with commercial QCM.

Results

Theoretical performance of RPT‐QC and commercial QCM‐QC are similar for 1‐3s with both n = 1 and 1‐3s with n = 2 for all measurands and both instruments. Achievable TEa values for RPT‐QC were close to ASVCP recommendations for most measurands; exceptions were PLT (both instruments) and WBC (scil Vet ABC).

Conclusions

Repeat patient testing‐based quality control advantages include a species‐specific matrix, low‐cost, and absence of QC material deterioration over time (since a fresh specimen is used each day). A potential disadvantage is daily access to normal canine specimens. A challenge is determining control limits, which has a subjective element. Further study is needed to confirm actual RPT‐QC performance and to determine if RPT‐QC with abnormal patient specimens is feasible.  相似文献   
3.
Microbial biomass N dynamics were studied under field and laboratory conditions in soils of high yield (HY) and low yield (LY) areas in an agricultural field. The objective of the study was to determine the size and activity of soil microbial biomass in the soils of the different yield areas and to compare these data obtained under field and laboratory conditions. Soils were amended with 15N labelled mustard (Sinapis alba) residues (both experiments) and labelled nitrate (laboratory only) at 30 μg N g−1 dry soil. Soil microbial biomass (SMB) N, mineral N (Nmin) and total N content was monitored both in the field and in the laboratory. N2O efflux was additionally measured in laboratory treatments. Isotope ratios were determined for SMB in both experiments, for all other parameters only in the laboratory treatments. In the laboratory less amounts of added substrate N were immobilised by the SMB in HY soils compared to LY soils, whereas in the field immobilisation of added N by SMB was higher in HY soils initially and slightly lower after 40 days of incubation. Calculated turnover times in the laboratory nitrate, laboratory mustard and field mustard amendments were 0.18, 0.27 and 0.74 years (HY) and 0.22, 0.61 and 1.01 years (LY), respectively. The turnover times of added substrate N always showed the trend to be faster in HY soils compared to LY soils. A faster turnover of nutrients in the HY soils may involve a better nutrient supply of the plants, which coincides with the higher agricultural yield observed in these areas.  相似文献   
4.
All forms of agriculture cause changes in the balances and fluxes of preexisting ecosystems, thereby limiting self-regulatory ecosystem (resiliency) functions. The intensive agriculture of the past, with its strong reduction of landscape structures and vast decoupling of energy and matter cycles, has caused stress and degradation of the production base; massive influence has also been exerted on neighboring compartments. This has resulted in the well known problems of pesticide loads, high phosphate loads to surface waters via over-fertilized soils or erosion as such. To overcome the economic, social and political inadequacies leading to ecological degradation, the demand for sustainable agricultural management needs to be transposed into knowledge-based practical instructions and political regulations on a regional scale. Thus, applied research for a sustainable and ecologically compatible land use aimed at sufficient food production is ever so important. In the FAM, thirty German research institutes have merged to perform research on this topic.  相似文献   
5.
6.
Danish agriculture is facing a turning point. Centuries of struggle to increase arable land area as well as its productivity is about to be reversed, due to overproduction and environmental problems. Some land will probably be turned back to nature, and the use of chemicals in agriculture in general will be reduced, perhaps with a lower productivity and a better environment as a consequence. This paper mainly describes some of the political actions taken in Denmark to influence environmental-agricultural issues. First, however, some of the recently perceived environmental problems and over-production problems connected with Danish farming are outlined.  相似文献   
7.
Effect of cell contact and iron(III)-oxide form on bacterial iron reduction By means of a semipermeable membrane the influence of the separation of cells from Fe(III)-oxides (125–63 μm) was studied in model experiments using iron-reducing bacteria (Clostridium butyricum S 22 a and Bacillus polymyxa S 55) which lower the Eh considerably. Synthetic sieved (125–63 μm) hematite (Merck) was included in dialytic bags (pores < 20 Å), incorporated in a glucose-mineral salt broth (pH 7–7.2) and inoculated (anaerobically, 30°C). Fe(II) production (in solution), pH and Eh were measured (and the rH calculated) at regular intervals. In the second experiment, the preferential reduction of lepidocrocite, hematite and goethite was investigated, by mixing 59Fe-labelled oxide forms with other crystalline oxides or with x-ray amorphous Go-soil material (all sieved at 125–63 μm).  相似文献   
8.
The epidemiologies of the most common diseases diagnosed in pigs at the Danish pig-breeding test stations were studied with special reference to possible genetic predisposition. The population under study comprised 9084 test pigs (corresponding to 3028 test groups) housed at nine test stations from September 1983 to September 1984. There were substantial differences between the four breeds in the study (Landrace, Yorkshire, Duroc and Hampshire) with the white breeds having higher clinical incidences of respiratory diseases and culling rates than the coloured ones. In only one of nine analyses was a significant sire effect found. However, significant differences were found between breeding centres of origin. There was a negative influence of clinical diseases on daily gain and feed conversion. Classifying respiratory disease in an ‘early’ form (at least one pig in the group was treated during the first 45 days of the test period) and a ‘late’ form (treatments were given after this period) showed that late infections resulted in a higher reduction of performance than early infections did. There were no associations between pathological findings at slaughter and growth rate.  相似文献   
9.
Munch J 《Science (New York, N.Y.)》1966,152(3729):1569-1570
  相似文献   
10.
The aim of the study was to measure the effect of radiological hip and elbow dysplasia status and breed on overall survival in a cohort of four large dog breeds in Norway. Privately owned dogs of the Newfoundland (NF), Labrador Retriever (LR), Leonberger (LEO), and Irish Wolfhound (IW) breeds were followed prospectively from birth to 10 years of age. The age of death/euthanasia was registered. A total of 501 dogs from 103 litters were enrolled. Kaplan-Meier survival curves were used to describe breed differences in survival times. The effects of radiological hip and elbow dysplasia status as well as breed were assessed using a Cox proportional hazards model. The variables 'sex' and 'living region' were explored as potential confounders. Among LRs, 60.2% of the dogs were still alive at 10 years of age, and the corresponding figures for NFs, LEOs, and IWs were 28.8%, 16.11%, and 6.4%, respectively. Radiological hip dysplasia status and breed were found to influence overall survival. Two different time-varying effects were observed in that with the IW the hazard of death increased linearly through time, while the effect of severe radiological hip dysplasia decreased logarithmically with time. Location influenced the death hazard and dogs living in suburban areas or cities had longer mean time to death and a lower hazard compared to dogs living in the countryside. Radiological elbow dysplasia status was not found to have an effect on overall survival.  相似文献   
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