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111.
In order to prove the effects of mass application of oral erysipelas vaccine via drinking water, in a farrow-to-finish production unit in Croatia, the growing-finishing animals were divided into 3 groups and treated as follows:--Group 1 (n=199) was vaccinated intramuscularly against swine erysipelas at 1 week and 3 weeks after arrival in the growing-finishing facility with a swine erysipelas bacterin.--Group 2 (n=199) were vaccinated at the same time with an avirulent culture of Erysipelothrix rhusiopathiae oral vaccine through drinking water.--Group 3 (n=200) was not vaccinated. Animals with clinical signs of swine erysipelas, chronic progressive arthritis at slaughter, mortality, average daily weight gain during the growing-finishing phase were evaluated. None of the pigs in the groups 1 and 2 showed clinical signs typical for acute swine erysipelas. Twenty-four of the pigs (12 %) in group 3 had pyrexia and skin lesions typical for swine erysipelas. Fifteen pigs in group 1, 13 pigs in group 2, and 63 pigs in group 3 had chronic progressive arthritis (group 1 and 2 vs. group 3: P < 0.01). No significant differences in mortality were recorded between the groups. Group 1 and 2 had higher (P < 0.05) average daily weight gains compared with the group 3.  相似文献   
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This study examines the possible predictive value of the LIVE/DEAD fluorescence viability assay for evaluation of survival of cryopreserved human ovarian tissue. Ovarian tissue from ten patients was examined by LIVE/DEAD viability staining before and after cryopreservation and after freezing in a -20 C freezer (negative control). After cryopreservation with a slow freezing protocol and cryoprotectant the LIVE/DEAD assay showed 86% viable follicles (an intact oocyte and at least more than 50% of the granulosa cells alive), whereas after freezing at -20 C the survival rate was 67%. The healthy follicular loss after cryopreservation was 4%, whereas with freezing at -20 C, it was 25%. Although this assay overestimates the survival rate of cryopreserved primordial follicles, if the LIVE/DEAD assay yields greater than approximately 85% viable follicles, it can be assumed that the follicles in the cryopreserved tissue have maintained their developmental potential and that the tissue is suitable for retransplantation.  相似文献   
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The location of and threats to biodiversity are distributed unevenly, so prioritization is essential to minimize biodiversity loss. To address this need, biodiversity conservation organizations have proposed nine templates of global priorities over the past decade. Here, we review the concepts, methods, results, impacts, and challenges of these prioritizations of conservation practice within the theoretical irreplaceability/vulnerability framework of systematic conservation planning. Most of the templates prioritize highly irreplaceable regions; some are reactive (prioritizing high vulnerability), and others are proactive (prioritizing low vulnerability). We hope this synthesis improves understanding of these prioritization approaches and that it results in more efficient allocation of geographically flexible conservation funding.  相似文献   
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Elementary chemistry distinguishes two kinds of strong bonds between atoms in molecules: the covalent bond, where bonding arises from valence electron pairs shared between neighboring atoms, and the ionic bond, where transfer of electrons from one atom to another leads to Coulombic attraction between the resulting ions. We present a third, distinct bonding mechanism: perpendicular paramagnetic bonding, generated by the stabilization of antibonding orbitals in their perpendicular orientation relative to an external magnetic field. In strong fields such as those present in the atmospheres of white dwarfs (on the order of 10(5) teslas) and other stellar objects, our calculations suggest that this mechanism underlies the strong bonding of H(2) in the (3)Σ(u)(+)(1σ(g)1σ(u)*) triplet state and of He(2) in the (1)Σ(g)(+)(1σ(g)(2)1σ(u)(*2)) singlet state, as well as their preferred perpendicular orientation in the external field.  相似文献   
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Leptospirosis is a bacterial zoonosis of worldwide distribution and is endemic in tropical countries, where rodents and other wild mammals are abundant and may act as reservoirs. Leptospirosis has become a concern in captive wild animals, due mostly to their exposure to contaminated urine or environment. Although domestic cats (Felis catus) have been reported refractory to leptospirosis, serology and disease in captive wild felids is still unclear. In this study 57 adult, clinically healthy felids, including 1 Geoffroy's cat (Leopardus geoffroyi), 3 jaguarundis (Puma yagouaroundi), 17 margays (Leopardus wiedii), 22 little spotted cats (Leopardus tigrinus), and 14 ocelots (Leopardus pardalis) kept in captivity at the Sanctuary at the Itaipu Binacional hydroelectric power plant (Bela Vista Biological Sanctuary), Foz do Iguacu City, Paraná State, Brazil, were serologically surveyed for the presence of antibodies against 28 serovars of Leptospira spp. by microagglutination test (MAT). Two animals (3.5%) were seropositive: one male ocelot to the serovar Cynopteri (titer 100) and one female margay to Autumnalis (100) and Butembo (200). The captive-born, 5-yr-old ocelot had been solitary housed in an individual cage. The approximately 21-yr-old wild-caught margay was also kept individually. None of the tested animals showed signs ofleptospirosis. During a study conducted 4 yr previously in the same facility, this particular margay also tested positive for the same two serovars, among others. The present study indicates that the felids tested for Leptospira spp. by MAT were exposed to serovars, but did not demonstrate clinical signs of disease. Comparison with a previous study suggests that serovar titers may vary over time and that leptospirosis dynamics remains unclear in wild felids.  相似文献   
117.
Genome‐wide association (GWA) mapping in potato requires high‐density genotyping. With the Illumina SolCAP potato single‐nucleotide polymorphism (SNP) array, a first tool for GWA mapping in potato became available. Thirty‐six tetraploid varieties and eight diploid breeding clones were genotyped for 8303 SNPs using this array. The objectives of our study were to examine in this set of germplasm: (i) the degree of polymorphism of the SolCAP SNPs in European germplasm, (ii) the population structure, (iii) temporal trends of genetic diversity and (iv) the genome‐wide extent of linkage disequilibrium (LD). Three‐quarters of the SNPs were polymorphic. In the principal coordinate analysis, a clear separation of tetraploid from diploid genotypes was observed, whereas no distinct subgroups among the tetraploid varieties were detected. The nonlinear trendline of the LD measure vs. the physical map distance decayed within 275 bp to an value of 0.10, indicating that theoretically, about 3 million equally distributed SNPs are required for GWA mapping in this diverse set of germplasm. As the LD decay changes with the population selected for GWA mapping, the number of required markers might be different in other germplasm.  相似文献   
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