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121.
The most important pork-borne zoonotic diseases in humans such as Salmonelloses and Yersinioses cause only latent infections in pigs. Thus, the infection of pigs does not result in apparent or palpable alterations in the pig carcasses. This is the major reason, why the traditional meat inspection with adspection, palpation and incision is not able to control the food safety risks of today. The objective of this paper is to evaluate a set of serological tests, which provides a classification of pig herds into “zoonoses risk categories” as demanded by EU law and into “herd health risk categories” by using meat juice as diagnostic specimen for ELISA tests. Serological data that were obtained by testing meat juice samples from various pig herds were analyzed as proof of the “meat juice multi-serology” concept. For that, at least 60 meat juice samples from 49 pig herds each were taken between September 2010 and March 2011 and tested for antibodies against zoonotic pathogens (Salmonella spp., Trichinella spp., Yersinia enterocolitica and Toxoplasma gondii) and against pathogens causing production diseases (Mycoplasma hyopneumoniae, influenza A virus subtype H1N1, influenza A virus subtype H3N2 and PRRSV). Apparent and true animal prevalence, herd prevalence values and intra-herd seroprevalence values as well as the predictive values for the herd and the animal prevalence values were calculated for each pathogen and each of the 49 randomly selected herds. The herd seroprevalence values (one seropositive sample per herd determined a “positive herd”) for Y. enterocolitica, Salmonella spp., T. gondii, M. hyopneumoniae and PRRSV were higher than 80%, respectively, for the influenza A viruses between 60% and 14% and for Trichinella spp. 0%. Although all herds were located in the same area in the Northwest of Germany within a radius of 250 km, the intra-herd seroprevalence values for all tested pathogens, except for Trichinella spp., varied remarkably from herd to herd. In the case of Y. enterocolitica and T. gondii the intra-herd seroprevalence values varied even from zero to 100%. This shows that a serological risk categorization of pig herds regarding zoonoses and production diseases is meaningful if used for risk-based decisions in the framework of the new meat inspection concept and as part of the herd health management system. Thus, the development of a cost-efficient, time- and labour-saving test system for simultaneously detecting various antibodies should be the next step for an extensive implementation of the meat juice multi-serology concept.  相似文献   
122.
The type VI secretion system (T6SS) is a virulence factor for many Gram-negative bacteria. Salmonella genus harbors five phylogenetically distinct T6SS loci encoded in Salmonella Pathogenicity Islands (SPIs) SPI-6, SPI-19, SPI-20, SPI-21 and SPI-22, which are differentially distributed among serotypes. The T6SSs encoded in SPI-6 and SPI-19 contribute to pathogenesis of serotypes Typhimurium and Gallinarum in mice and chickens, respectively. Salmonella Dublin is a pathogen restricted to cattle where it causes a systemic disease. Also, it can colonize other hosts such as chickens and mice, which can act as reservoirs of this serotype. Salmonella Dublin harbors the genes for both T6SSSPI-6 and T6SSSPI-19. This study has determined the contribution of T6SSSPI-6 and T6SSSPI-19 to host-colonization by Salmonella Dublin using avian and murine models of infection. Competitive index experiments showed that, a mutant strain lacking both T6SSs (∆T6SSSPI-6/∆T6SSSPI-19) presents a strong colonization defect in cecum of chickens, similar to the defect observed for the ∆T6SSSPI-6 mutant, suggesting that this serotype requires a functional T6SSSPI-6 for efficient colonization of the avian gastrointestinal tract. Colonization of mice was also defective, although to a lesser extent than in chickens. In contrast, the T6SSSPI-19 was not necessary for colonization of either chickens or mice. Transfer of T6SSSPI-6, but not T6SSSPI-19, restored the ability of the double mutant to colonize both animal hosts. Our data indicate that Salmonella Dublin requires only the T6SSSPI-6 for efficient colonization of mice and chickens, and that the T6SSSPI-6 and T6SSSPI-19 are not functionally redundant.  相似文献   
123.
Rat liver sections and a human epithelial cell line (HEp-2) were compared as substrates for the detection of antinuclear antibodies (ANA) in the serum of normal dogs and dogs with suspected autoimmune disease, using a standard indirect immunofluorescence (IIF) technique. Antibody reactivity against rat hepatocyte nuclei was frequently found at low serum dilutions in normal dog sera. Using rat liver sections, a minimum significant positive titer, allowing negativity in more than 95% of normal dog sera, was found to be 1/100. With this titer, ANA positivity could be verified in 64 of 112 (57%) reanalysed serum samples from dogs with suspected autoimmune disease, earlier determined as ANA-positive. No reactivity against nuclei of HEp-2 cells was observed in any of the normal dog sera analyzed at a screening dilution of 1/25. Using this dilution as a minimum significant positive titer, 63 of the 112 (56%) re-evaluated serum samples were positive. These 63 samples were from the same dogs as the 64 samples that were positive on rat liver sections. Thus, the 2 methods of ANA-IIF detected a nearly identical population of dogs with suspected autoimmune disease once the level of significance of a positive titer was adjusted to 195% specificity for each method. HEp-2 cells were found to be superior to rat liver cryostate sections as ANA substrate because of their low reactivity with normal sera, and the ease of discernment of the ANA fluorescence pattern. The recognition and documentation of specific pattern types may give clues to ANA subspecificities, which could prove useful if they are found to correlate with well-defined subgroups of immune mediated clinical diseases in dogs. J Vet Intern Med 1996;10:199–203. Copyright © 1996 by the American College of Veterinary Internal Medicine .  相似文献   
124.
California's 14-year, $25 million acidic deposition program has studied the causes and effects of acidic air pollutants. In contrast to the eastern United States where sulfur-derived (S-derived) by-products from coal combustion dominate precipitation chemistry, nitrogen-derived (N-derived) acids predominate in wet and dry deposition in California. Adverse effects on the human lung have not been observed after short-term exposures to acidity, but extended exposures to ambient acidity may pose a chronic risk. No irreversible, adverse effects on surface waters in the Sierra Nevada mountain range or to the state's forests have been found due to extant acidic inputs. The longer-term outlook for forests is less certain because the impacts observed elsewhere occurred after decades of S and N deposition, but at lower ambient ozone levels. Ozone is the major air pollutant stressor for forests, but atmospheric N has the potential to cause adverse changes in soil nutrient cycling. Impacts on man-made materials in southern California (e.g., galvanized steel) were found to be minor. While California does not have an ambient air quality standard for acidic air pollutants, emissions of precursors have declined since the 1960's due to changes in industrial practices, improvements in technology, and adoption of control measures for ozone. Lowering emissions from motor vehicles will be emphasized to prevent future increases in N deposition.  相似文献   
125.
Polyphenols are an important functional minor component of virgin olive oils that are responsible for the key sensory characteristics of bitterness, pungency, and astringency. Polyphenols were isolated from virgin olive oils by using liquid/liquid extraction and then separated by using reverse phase HPLC followed by fraction collection. The sensory qualities of the isolated polyphenols were evaluated, and almost all fractions containing polyphenols were described as bitter and astringent. However, the fraction containing deacetoxy-ligstroside aglycon produced a strong burning pungent sensation at the back of the throat. In contrast, the fraction containing the analogous deacetoxy-oleuropein aglycon, at an equivalent concentration, produced only a slight burning/numbing sensation, which was perceived more on the tongue. No other polyphenol fractions from the analyzed oils produced the intense burning sensation; thus, deacetoxy-ligstroside aglycon is the polyphenol responsible for the majority of the burning pungent sensation found in pungent extra virgin olive oils.  相似文献   
126.
A weighted, random sample of 130 horse owners in Tennessee was selected from subscribers to an equine newsletter published by the Agricultural Extension Service. Data about the participants' farms, horses, parasite control practices, and sources of information regarding equine parasite control were obtained through a telephone survey. The response rate was 98%. The typical respondent kept 4 horses on 2 pastures totaling 15 acres, and did not rotate pastures as a parasite control measure. The majority (83%) of horse owners indicated that they administered anthelmintics according to a regular schedule; 9% delayed deworming until the onset of weight loss. Proportions of owners deworming the various classes of horses at least 1, 2, 3, or 4 times annually were as follows: foals (0 to 6 months) 100, 60, 15, and 0%, respectively; weanlings (6 to 12 months) 100, 91, 32, and 0%, respectively; yearlings (1 to 2 years) 100, 100, 86, and 51%, respectively; and adults (greater than 2 years) 100, 94, 56, and 24%, respectively. Median treatments of yearlings and adults were evenly spaced at 6-, 4-, or 3-month intervals when the owners dewormed 2, 3, or 4 times annually, respectively. Mean intervals between treatments of foals and weanlings were less regular. Of the horse owners who dewormed 2 or more times annually, most (53 to 80%) used the same product exclusively for all treatments. In all age classes of horses, ivermectin paste (46 to 63%) was the most common product used, followed by tube deworming (23 to 38%) and use of benzimidazoles (4 to 16%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
127.
Neutralisation tests for antibodies against ovine herpesvirus were applied to 848 sera which had been sampled from different sheep herds across the GDR. Between six and 20 percent of sheep in the herds tested exhibited neutralising antibodies, notwithstanding their pulmonary adenomatosis status. Incidence and titre distribution of antibodies against ovine herpesviruses in pulmonary adenomatosis herds were identical with those recorded from unsuspected herds. From among 21 sheep with pathomorphologically secured pulmonary adenomatosis, six animals exhibited antibody titres just as high as those recorded from responders of all herds examined. Lambs were obtained by hysterectomy and raised without mothers and were experimentally infected with Herpesvirus ovis. All of these animals responded to infection by clearly rising titres (between 1:2 and 1:32). Adenomatous pulmonary lesions were not recordable from any of them. One lamb, following experimental ovine herpesvirus infection, exhibition, exhibited subclinical interstitial pneumonia. Herpesvirus ovis has been widespread in sheep herds across the GDR. The authors' serological and experimental investigations do not support the assumption of an aetiological relationship between ovine herpesvirus infection and incidence of pulmonary adenomatosis.  相似文献   
128.
Trichuris suis population kinetics was studied by experimentally infecting 40 pigs with 5000 T. suis infective eggs. Six pigs were sacrificed every 2 weeks from 1 to 9 weeks post-inoculation (p.i.) and the remaining 10 pigs were sacrificed 11 weeks p.i. to estimate worm burdens. An equal number of uninfected control pigs were sacrificed at the same time points for comparison. Egg excretions from each pig were evaluated every week from 5 to 11 weeks p.i. Peripheral blood eosinophilia and basophilia were also evaluated every 2 weeks throughout the experimental period. After an initial almost 100% establishment of T. suis an expulsion phase followed approximately 9 weeks p.i., resulting in an aggregated distribution of the worms in the pig population, as it is characteristic for most helminth infections. By 11 weeks p.i. almost all worms had been expelled. Egg excretion peaked 7 weeks p.i. and a significant non-linear relationship between worm burdens and egg excretion was found. The predilection site for T. suis was the caecum and proximal colon and the relative distribution of worms in the large intestine did not change over time until expulsion. Peaking peripheral blood eosinophil and basophil levels were observed in the T. suis infected pigs 5 and 7 weeks p.i., respectively, reflecting the host activated immune response against the parasite. We here describe the course of a primary T. suis infection in pigs by detailed worm counts, demonstrating an effective expulsion that results in an almost 100% clearance of infection as previously indicated by monitoring faecal egg excretion.  相似文献   
129.
The paper describes the introduction of Mycobacterium bovis into Swedish deer herds and its possible consequences. The different control strategies applied are summarized as well as their shortcomings under the conditions of the Swedish outbreak. An alternative control, to be used in extensive deer herds, based only on slaughter and meat inspection is described. Finally, the efficiency of the implemented control and surveillance systems are discussed and possible improvements suggested.  相似文献   
130.
OBJECTIVE: To create a mathematical model to assist in early prediction of the probability of discharge in hospitalized foals < or= 7 days old. STUDY DESIGN: Prospective study. ANIMALS: 1,073 foals. PROCEDURES: Medical records from 910 hospitalized foals < or = 7 days old for which outcome was recorded as died or discharged alive were reviewed. Thirty-four variables including historical information, physical examination findings, and laboratory results were examined for association with survival. Variables associated with being discharged alive were entered into a multivariable logistic regression model. Accuracy of the model was validated prospectively on data from 163 foals. RESULTS: Factors in the final model included age group, ability to stand, presence of a suckle reflex, WBC count, serum creatinine concentration, and anion gap. Sensitivity and specificity of the model to predict live discharge were 92% and 74%, respectively, in the retrospective population and 90% and 46%, respectively, in the prospective population. Accuracy of an equine clinician's initial prediction of the foal being discharged alive was 83%, and accuracy of the model's prediction was 81%. Combining the clinician's prediction of probability of live discharge with that of the model significantly increased (median increase, 12%) the accuracy of the prediction for foals that were discharged and nonsignificantly decreased (median decrease, 9%) the accuracy of the predication for nonsurvivors. CONCLUSIONS AND CLINICAL RELEVANCE: Combining the clinician's initial predication of the probability of a foal being discharged alive with that of the model appeared to provide a more precise early estimate of the probability of live discharge for hospitalized foals.  相似文献   
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