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61.
Currently, the diagnosis of bovine spongiform encephalopathy is only possible in the brain stem of dead animals. Protease resistant prions are detected in the obex region of the brain stem. However, from a veterinary medical and agricultural point of view the development of an in vivo detection assay is of utmost importance. Because infectious prions are detectable relatively late in the central nervous system during an infection, efforts are made searching for surrogate markers. Besides neuronal proteins that are released into the liquor and blood during neurodegenerative processes or other neuronal diseases, cellular nucleic acids circulating in the plasma or serum are an absolutely new approach for the detection of infectious diseases.  相似文献   
62.
The effect of conjugated linoleic acid (CLA) on blood lipids [total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triacylglycerols (TAG)] and the fatty acid distribution of the lipoprotein fractions, backfat, muscle fat, and liver lipids were examined in an experiment with two groups of 40 pigs [Pietrain x (Landrace x Large White)] each. The 20 female and 20 male castrated pigs of each group were fed with isoenergetic and isonitrogenous diets supplemented with either 20 g/kg rapeseed oil (control) or 20 g/kg CLA-TAG. The CLA preparation contained 54.2% pure CLA consisting of approximately two-thirds cis,trans/trans,cis-isomers and one-third trans,trans-isomers. The fatty acids of lipoproteins, backfat, muscle lipids and liver lipids were analysed by gas chromatograph (GC). CLA supplementation did not significantly influence blood lipids and the LDL to HDL ratio. In the CLA-fed pigs the very low-density lipoprotein (VLDL) contained higher saturated fatty acid (SFA) concentrations at the cost of the monounsaturated fatty acids (MUFA). The percentage of polyunsaturated fatty acids (PUFA) remained unchanged. The highest CLA content was analysed in VLDL (4.00%) followed by LDL (2.78%) and HDL (1.45%). The ratio of cis,cis to trans,trans isomers increased from VLDL over LDL to HDL. The content of SFA, probably in backfat and muscle lipids, increased whereas the part of MUFA decreased as a result of reduced Delta9-desaturase activity. The percentage of PUFA (without CLA) was higher in backfat of the control group in accordance with the dietary PUFA supply. This shift in the fatty acid distribution was not observed in the liver lipids. In all the three tissues analysed, the CLA-fed pigs had a significantly increased CLA content: the highest increase was in the backfat (5.65%), followed by liver lipids (2.41%), and muscle lipids (1.47%). An isomer-specific accumulation was observed for cis,cis-CLA isomers in muscle, and for trans,trans-CLA isomers in backfat. We conclude that CLA supplementation results in a higher SFA content in backfat and muscle lipids but not in liver lipids. There is a discrimination of the trans-10, cis-12 isomer and the trans,trans isomers in the formation of the cell membranes.  相似文献   
63.
ABSTRACT Strawberry fields in California (9,500 ha annually) are pre-plant fumigated with methyl bromide and chloropicrin to prevent serious soil pest and disease problems. Although soil fumigation with methyl bromide has ensured stability of strawberry production, its use is being discontinued because of its effect on stratospheric ozone. The likely short-term alternatives such as 1,3-dichloropropene, chloropicrin, and metham sodium, although not ozone depleters, are potentially hazardous to the environment and humans if applied improperly. Water-soluble formulations of alternative fumigants can be applied through drip irrigation systems established to irrigate crops. In comparison to conventional shank methods of injection, application of soluble formulations through drip irrigation systems would be economical and environmentally friendly, reduce worker exposure, and allow for simultaneous or sequential application of a combination of fumigants. This paper discusses techniques developed to apply alternative fumigants through drip irrigation systems, and reviews ongoing studies to determine optimum application rates, soil conditions, plastic mulches, and amount of irrigation water used to apply these alternative fumigants.  相似文献   
64.
Reports of human salmonellosis caused by the consumption of pork and the introduction of control and surveillance programmes in different countries of the European Union were the reason for carrying out an international study under the title "Salmonella in Pork (Salinpork)": Six different EU-countries were involved in this study, which was supported by the Commission of the European Community and which was carried out over a period of April 1996 to April 1999. The aim of the investigation presented was to determine the prevalence of Salmonella in fattening, breeding and farrow-to-feeder herds as well as the determination of risk factors for the introduction of Salmonella into the farm (Part 1). In addition, sources of contamination of pork should be detected by taking samples of the product and the environment in the slaughterhouse (Part 2). In Germany, the investigation into Salmonella infections of 60 fattening, 20 breeding and 20 farrow-to-feeder herds were carried out in Schleswig-Holstein. The investigation included bacteriological examinations of feed and faecal samples for sero- and phagetyping and serological examinations by using the Danish Mix-ELISA. From 2,947 serological investigated fattening pigs were 7.3% (n = 213) positive, from 797 breeding sows 9.2% (n = 73) were serological positive and 4.5% (n = 18) of the investigated sows (N = 399) in farrow-to-feeder herds were serological positive. Altogether, 28.3% of the fattening, 50.0% of the breeding and 15.0% of the farrow-to-feeder herds were serological positive. A questionnaire was used to capture data about management, hygiene measures, feeding systems and the occurrence of diseases in the herd. After statistical analysis the common risk factor of fattening herds and sow herds was the use of pelleted feed. But in a control study with 17 different fattening herds the result could not be proven. Other factors which can influence the occurrence of Salmonella infections were discussed.  相似文献   
65.
In 1997 bacteriological examinations for the distribution of Salmonella in slaughterhouses were carried out in Germany within the framework of an international study "Salmonella in Pork (Salinpork)". During 6 days, 1,200 swab and water samples from slaughtered pigs and the environment were taken. 4.4% of the samples (n = 53) were Salmonella positive. S. typhimurium was isolated mainly (69.8%; n = 37), and 6 phagetypes were differentiated. In addition, S. derby and S. panama could be demonstrated. The resistance pattern of the different isolated S. typhimurium-phagetypes are presented. The phagetype DT 104 was multiresistant to ampicillin, spectinomycin, streptomycin, sulphonamide and tetracycline. In comparison with the serological prevalence of 7.3% of the fattening pigs in the farms (Part 1), only 1.0% of the samples taken from the surface of the carcass were Salmonella-positive. Swabs taken from the liver were in 2.7% positive and samples from the tongue gave in 5.3% of the cases Salmonella-positive results. In the examination of the environment Salmonella was demonstrated mainly from the water outlets, whereas Salmonella could not be isolated from water of the scalding tank. There was only one case (0.7%) in which Salmonella could be isolated from the hands of the personnel, and also only one swab of the polishing machine was positive (1.1%). But 6.7% samples of the saw were Salmonella-positive. A comparison of repeated, at intervals taken samples showed that the number of Salmonella-positive samples was higher in the last examination round of the particular slaughter days. The reason is suspected in the increasing number of slaughtered pigs and supplying farms, which may increase the probability of bringing in Salmonella.  相似文献   
66.
The article surveys the development of legislation to the slaughtering of warm-blooded animals in Germany since 1933. It examines the ritual slaughtering of the Jews (Schechita) on the one hand, and of the Moslems (Dabh) on the other hand. While 1933 the legislation was coined by the political situation, after 1949, legal setting and decisions reflected the changing sensibility to animals' protection. Before 1945, Schechita was the matter of legal dispute, more recently, the discussion has centred on the ritual slaughtering of the Moslems, with different arguments. The "Law on the Slaughtering of Animals" of 21-04-33 was part and parcel of the Third Reich's policy against Jews implicating a nation wide practical inhibition of Schechita by decreeing a general obligation of stunning before slaughtering. In 1945, the inhibition of Schechita became invalid after the occupation of the Reich by the Allied Forces. For the first time, the "First Amendment to the Animal Protection Law" of 1986 permitted ritual slaughtering by the way of exception as long as it was covered by the religious obligations. In 1995 the Federal Administrative Court judged that an inhibition of the ritual slaughtering by Moslems could be possible, because there are no religious obligations for Moslems. Nowadays, the ritual slaughtering of the Moslems is, de facto, forbidden, Schechita is performed in some cities for the needs of the residential Jewish population.  相似文献   
67.
Because of the growing interest in animal health and welfare in breeding and sport--specially in the horse--the regulation of the German Riding Association (FN) was updated. The result--the LPO 2000--refer more functions to the veterinarian. At first the permanent presence of the vet is necessary, at second he controls the correct, new installed vaccination against influenza-virus. The functions of vet-check, general horse-control and doping are wide up in number and consultation. For this the veterinarian must decree about much experience and good preparation. The organisations of the veterinarians of the countries and the FN work together to develop the knowledge and competence in horse-sport for a better protection.  相似文献   
68.
In a two years lasting trial the N-release of organic N-fertilizers should be analysed under covered fallow plots during the vegetation period. The following fertilizers were proved: cattle manure from two locations, “Vinasse” (product resulting from the converting of sugar-beet molasses), “Haarmehlpellets” (pellets of grounded pig bristles), “Rizinusschrot” (grist of the seed of Ricinius communis), “Rapsschrot” (coarse colza meal), “Phytopearls” (residue of maize converting), “Maltaflor” (malt germs and “Vinasse”), “Agrobiosol” (biomass from Penicillium) and “Horndünger” (horn parings in different fractions). In comparison with these organic fertilizers the mineral N-fertilizer calcium-ammonium-nitrate was used. With the exception of the control all variants got an annual N-fertilization of 90?kg?N/ha. The N-mineralisation of the soil caused by the organic substance, which was in the soil before the trial started, amounted to 84?kg?N/ha in the first and to 59?kg?N/ha in the second year of experience. In both years the N-mineralisation was higher in the second half of the vegetation period (July–November) than in the first half (March–July). In the first year the amount of N-release was clearly less than the given quantity of the N-fertilizer with the exception of “Agrobiosol”. Especially the two manure-variants showed N-immobilisation. “Agrobiosol” showed the highest N-release of the tested organic N-fertilizers. In the second year the N-release both of the two manure-variants and of “Rapsschrot”, “Phytoperls”, “Maltaflor”, “Agrobiosol” and “Horndünger” increased clearly. It was between 51 and 101% of the N-quantity given in the second year. N-release was particularly high by “Agrobiosol”, “Horndünger” and “Rapsschrot”. This increase could be traced to the mineralisation of the remained organic substance given in the first year. The variants “Haarmehlpellets” and “Rizinusschrot” had the same N-release as in the first year. The application of “Vinasse” showed a clear decrease. When “Rapsschrot”, “Phytoperls”, “Maltaflor”, “Agrobiosol”, “Horndünger” or manure are given for many years, one can consequently count on an increase of the annual N-mineralisation. Considering the results of both years of the trial the organic fertilizers “Agrobiosol”, “Horndünger” and “Maltaflor” can be classified as quickly effectiveN-fertilizers, “Haarmehlpellets”, “Rizinusschrot” and “Phytopearls” as moderately effective and “Rapsschrot” and “Vinasse” as slowly effective ones.  相似文献   
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