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11.
Parasitic bronchitis caused by the bovine lungworm, Dictyocaulus viviparus, occurs worldwide in temperate areas. The parasite is found predominantly in calves and heifers, but dairy cattle can suffer from lungworms when they become infected for the first time or if they have lost immunity due to lack of exposure to lungworm larvae during the grazing season. The present study was performed to determine the D. viviparus bulk milk antibody prevalence in dairy herds in the East Frisian region of northwestern Germany, Lower Saxony, by analysing bulk milk samples collected in January (860 samples), September (866 samples) and November (860 samples) 2008, thereby representing 906 dairy farms. These samples were tested for antibodies against D. viviparus by a milk ELISA. This test detects patent infections only since it is based on recombinant major sperm protein as antigen. While in January 12.8% of dairy farms were positive for D. viviparus antibodies, the bulk milk samples collected in September and November revealed 6.9% and 6.6% positive dairy herds. From the 906 dairy farms included in the study, 191 (21.1%) tested positive at least once for antibodies against lungworm. From 810 dairy farms from which bulk milk samples were obtained during all three samplings, 146 (18.0%) farms were positive at one sampling date, 27 (3.3%) at two, and 4 (0.5%) on all three sampling dates. The majority of the farms represented in the study belonged to four districts of East Frisia, which showed no significant difference in the proportion of positive dairy farms.  相似文献   
12.
This study outlines the results of analysis of soil samples collected from fixed quadrats located in a regular pattern across Wytham Wood. Oxfordshire, England. The site contains plots of mixed deciduous ancient woodland and more recent plantations. A previous soil study was undertaken in 1974 and samples archived. Soils were resampled in 1991 and some re-analysis of the 1974 samples was undertaken. Soils were of a wide range in types from sands to gravels with a pH range of 3.0–7.0. Results showed some decline in pH in lower horizons, but most striking was a large increase in soil nitrogen for all horizons and soil types.  相似文献   
13.
The anticarcinogenic effect of garlic has been demonstrated in both epidemiologic and experimental studies. In this study, possible mechanisms involved in the anticarcinogenic effect of garlic consumption were assessed by determining its capacity to alter drug metabolizing enzymes, in relation with its alliin content. Rats were fed a diet for 2 weeks containing 5% garlic powders produced from bulbs grown on soils with different levels of sulfate fertilization and therefore containing differing amounts of alliin. Activities of several hepatic enzymes, which are important in carcinogen metabolism such cytochromes P450 (CYP) and phase II enzymes, were determined. Garlic consumption slightly increased ethoxyresorufin O-deethylase and CYP 1A2 levels. In contrast, garlic consumption decreased CYP 2E1 activity and the level of the corresponding isoform. UDP glucuronosyl transferase and glutathion S-transferase activities were increased by garlic powders. The alliin content of the garlic powders was positively correlated with UGT activity although not with other activities. Effects produced by garlic consumption were qualitatively similar to that of diallyl disulfide, a sulfur compound that has been extensively studied. These data could partially explain the chemoprotective effect of garlic.  相似文献   
14.
The effect of fat content on the release of volatile aroma compounds from frankfurters has been investigated. Although the release of most n-alkanals, alcohols, ketones, and furans was little affected by changes in the fat content of frankfurters, that of monoterpene hydrocarbons, sesquiterpene hydrocarbons, terpenes containing oxygen, cyclopentenones, phenyl propanoids, and phenols was greatly increased when the fat content was decreased. Some odors were also detected more frequently in the low-fat than in the full-fat sausages. These included smoky odors, due to phenols, spicy, synthetic, and floral odors due to terpenes, and meaty, roasted odors caused by sulfur-containing heterocyclic compounds. The release of aroma compounds from frankfurters appears to be closely related to the solvation of these compounds in the lipid phase.  相似文献   
15.
16.
Total serum alkaline phosphatase (ALP) activity is the product of the combined activity of isoenzymes from a number of tissue sources. In this study, a commercially available kit for electrophoretic separation of ALP isoenzymes in an agarose gel was used to separate ALP isoenzymes in feline tissue extracts and serum. Five separate bands of ALP activity were identified. These bands were numbered 1 to 5 with band 1 having the most anodal migration. The tissue of origin corresponding to the migration position of the isoenzymes are as follows: Band 3 was the liver isoenzyme, band 4 was the bone isoenzyme and ALP isoenzymes of both intestine and kidney migrate in the position labelled band 5. Band 1 appears to be related to albumin and does not represent true ALP activity. The tissue source of band 2 (a and b) was not identified. Serum ALP activity of mature, healthy cats is primarily of liver origin. Immature cats (< 1 year of age) have a greater proportion of the bone isoenzyme in the serum.  相似文献   
17.
Identification of major volatile odor compounds in frankfurters   总被引:1,自引:0,他引:1  
More than 100 volatile compounds have been identified in the headspace of frankfurter sausages. Most abundant were the terpene hydrocarbons, monoterpene alcohols, phenyl propanoids, and phenols. Separate analyses of solutions of spices and smoke demonstrated that most of the terpenes were derived from the spices, whereas the phenols originated mostly from the smoke ingredients. Many of the compounds contributing to the overall odor of the frankfurters have been identified. Some odors, characteristic of the smokiness and spiciness of frankfurters, were caused by phenols and terpenes, whereas others were due to compounds derived from the meat fraction; these compounds included aldehydes, ketones, furanthiols, and alicyclic sulfur compounds.  相似文献   
18.

Background

Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii. Prevalence data in ruminant species are important to support risk assessments regarding public and animal health. The aim was to investigate the presence of or exposure to C. burnetii in cattle, sheep, goats and moose, and to compare two enzyme-linked immunosorbent assays (ELISAs). National surveys of antibodies against C. burnetii were performed for dairy cattle (n=1537), dairy goats (n=58) and sheep (n=518). Bovine samples consisted of bulk milk, caprine of pooled milk, and ovine of pooled serum. Antibodies were investigated in moose samples (n=99) from three regions. A one-year regional cattle bulk milk survey was performed on the Isle of Gotland (n=119, four occasions). Cattle, sheep and goat samples were analysed with indirect ELISA and moose samples with complement fixation test. For the sheep, goat, and parts of the cattle survey, samples were run in parallel by ELISAs based on antigens from infected ruminants and ticks. Bulk milk samples from the regional cattle survey and vaginal swabs from a subset of the sheep herds (n=80) were analysed for the agent by polymerase chain reaction. Spatial clustering was investigated in the national cattle survey.

Results

The prevalence of antibodies in dairy herds was 8.2% with large regional differences. High risk clusters were identified in the southern regions. The prevalence among dairy herds on the Isle of Gotland varied from 55.9% to 64.6% and 46.4% to 58.9.0% for antibodies and agent, respectively, overall agreement between agent and antibodies was 85.2%. The prevalence of antibodies in sheep was 0.6%, the agent was not detected the vaginal swabs. Antibodies were not detected in goats or moose, although parts of the moose samples were collected in an area with high prevalence in cattle. The overall agreement between the two ELISAs was 90.4%.

Conclusions

The prevalence of antibodies against C. burnetii in dairy cattle in Sweden shows large regional differences. The results suggest that C. burnetii is a rare pathogen among Swedish moose, dairy goat and sheep. ELISAs based on ruminant and tick antigen performed in a similar manner under Swedish conditions.  相似文献   
19.
Concern about the environmental effect of air pollution on areas of high conservation value in the UK has prompted the statutory agencies to initiate an investigation on these areas. For this, critical loads maps have been used together with predicted air pollution data, monitored air pollution data and remotely sensed land cover information within a geographic information system (GIS). Additional information on designated Sites of Special Scientific Interest (SSSI) for England and Wales have also been incorporated. This provides the framework for examining potential impacts to these sites under various current and future scenarios. The approach allows for the investigation of the impacts of individual point sources as well as complete national scenarios. Preliminary results are provided from analysis of a single pollutant (sulphur). These indicate that nationally up to 52% of the area of SSSI's (5000 km2) are at risk from soil acidification. Using this approach it has been possible to apportion the load on any SSSI, thereby enabling the ecological impacts of each point source to be identified. This information can then be used to assess priorities for regulatory controls.  相似文献   
20.
Three types of yeast extract pastes from two different suppliers were compared. Compounds responsible for the key odors include 2-methyl-3-furanthiol, 2-methyl-3-methyldithiofuran, methional, 1-octen-3-one, dimethyltrisulphide together with a number of pyrazines, thiophenes, and aliphatic compounds. The three types of yeast extract paste differed in the intensity of their main odors and, in particular, those caused by furans, furanthiols, and heterocyclic sulfur compounds. Not only do pastes from different suppliers differ in terms of odor volatiles, but so do different treatments and batches of yeast extract from one supplier. The results suggest that normal variations in the concentrations of precursors and processing conditions may cause variations in the flavor of the end product.  相似文献   
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