Überprüfung der Wirksamkeit stallspezifischer Vakzinen zur Bekämpfung der Dermatitis digitalis bei Milchkühen

Überprüfung der Wirksamkeit stallspezifischer Vakzinen zur Bekämpfung der Dermatitis digitalis bei Milchkühen Die Studie wurde als kontrollierter Doppelblindversuch durchgeführt. Die Untersuchungen fanden in einem Milchviehbetrieb in Norddeutschland statt (429 Tiere bei der ersten Untersuchung). Aus den Hautbioptaten typischer DD-Läsionen wurden folgende Erreger im anaeroben Bereich isoliert: Porphyromonas ssp., Porphyromonas levii, Porphyromonas endodonatales, Fusobacterium necrophorum, Bac. stercoris, Prevotella bivis, Peptostreptococcus indolicus, Treponema sp.. Daraus wurden zwei formalininaktivierte Adsorbatvakzinen hergestellt. Die eine enthielt alle Keimarten außer Treponema sp. (Impfgruppe A), die andere alle Keimarten und Treponema sp. (Keimanteil 20 %) aus einer Schüttelkulturvermehrung (Impfgruppe B). Als Placebo wurde die Impflösung ohne Antigen verwendet (Kontrollgruppe). Verabreicht wurden je 5 ml Impfstoff oder Placebo subkutan. Der Klauengesundheitsstatus wurde im Oktober 1998, März 1999, Oktober 1999 und im Januar 2000 im Rahmen der halbjährlich durchgeführten funktionellen Klauenpflege erfasst und die Befunde der Hintergliedmaßen dokumentiert. Die erste Impfung erfolgte im Dezember 1998, die zweite drei Wochen später, die weiteren Impfungen fanden im März 1999 und im November 1999 statt. Zwischen der ersten und vierten Untersuchung durchgeführte Klauen- und Antibiotikabehandlungen wurden vom Betriebsleiter protokolliert. Die Auswertung erbrachte folgende Ergebnisse: 1. Zu keinem der vier Untersuchungszeitpunkte bestanden signifikante Unterschiede bezüglich der Prävalenzen der DD in den zwei Impfgruppen und der Kontrollgruppe. Die Prävalenzen der DD bewegten sich zum Zeitpunkt der vier Untersuchungen um 36 %, 42 %, 51 % und 38 %. 2. An Hintergliedmaßen, die bei der Erstuntersuchung DD-Läsionen aufwiesen, konnten auch bei den Folgeuntersuchungen in den zwei Impfgruppen und der Kontrollgruppe jeweils etwa gleichhäufig derartige Veränderungen diagnostiziert werden. 3. An Hintergliedmaßen, die bei der Erstuntersuchung frei von DD waren, konnten bei den Folgeuntersuchungen in den zwei Impfgruppen und der Kontrollgruppe jeweils etwa gleichhäufig DD-Läsionen diagnostiziert werden. 4. Die Scorewerte (nach DÖPFER, 1994) DD positiver Tiere - als Maßzahl für den Schweregrad der DD-Veränderung - waren zu den vier Untersuchungszeitpunkten in den zwei Impfgruppen und der Kontrollgruppe statistisch nicht signifikant verschieden. 5. Der „maximale gewichtete Flächenindex (max. GFI)“ - als weitere Bewertungsgrundlage für den Schweregrad der DD - war bei den Untersuchungen U2 und U3 in den Impfgruppen und der Kontrollgruppe nicht statistisch signifikant verschieden. Bei U1 war in der Impfgruppe B ein statistisch signifikant höherer Mittelwert (x) festzustellen als in der Kontrollgruppe (x = 82; p = 0,006). Bei U4 war in der Kontrollgruppe ein statistisch signifikant niedrigerer Mittelwert (x) festzustellen als in den Impfgruppen (x = 22,5; p = 0,033). 6. Die Häufigkeit von Klauen- und Antibiotikabehandlungen sowie der Einfluss von DD-Läsionen auf die Abgangsursache waren in den zwei Impfgruppen und der Kontrollgruppe statistisch nicht signifikant verschieden. In der vorliegenden Impfstudie konnte weder eine prophylaktische noch eine therapeutische Wirkung durch die verwendeten stallspezifischen Vakzinen bei der Bekämpfung der Dermatitis digitalis festgestellt werden. Auch das Hinzufügen von Treponema sp. erbrachte keinen Effekt auf die Wirksamkeit des Impfstoffs.Evaluation of the efficacy of herd-specific vaccines for the control of digital dermatitis in dairy cows. The study was realised in the form of a controlled double blind clinical trial. The investigations were carried out on a dairy farm in northern Germany (429 cows at the first check). The following anaerobic germs were isolated from skin biopsies of typical DD-lesions: Porphyromonas ssp., Porphyromonas levii, Porphyromonas endodonatales, Fusobacterium necrophorum, Bac. stercoris, Prevotella bivis, Peptostreptococcus indolicus, Treponema sp.. Two kinds of formalin-inactivated vaccines were prepared from the isolates. One contained all isolates except Treponema sp. (administered to group A), the other all isolates, including Treponema sp. (20 % of total count) grown in a roundshaker (this vaccine was administered to group B). A solution without antigen served as placebo (control group). Five ml were injected subcutaneous at each administration. Claws were inspected in October, 1998, March, 1999, October, 1999 and January, 2000, during routine semi-annual trimming sessions and findings on hind claws were recorded. The first vaccination was carried out in December, 1998, the 2nd one three weeks later, the 3rd one in March, 1999, and the 4th one in November, 1999. All treatments for claw diseases and applications of antibiotics between the first and the fourth check were recorded by the farmer. The evaluation produced the following results: 1. At the time of all examinations, no significant differences in prevalences of DD existed between any of the groups. Prevalences of DD at the four examinations were arround 36 %, 42 %, 52 % and 38 %. 2. In subsequent examinations of hind legs on which DD lesions had been found at the first examination, no difference was observed between any of the groups as regards the extent to which alterations of this nature were diagnosed. 3. In subsequent examinations of hind legs which had been found to be free of DD lesions at the first examination, no difference was observed between any of the groups as regards the extent to which DD lesions were diagnosed. 4. Score values (according to DÖPFER, 1994) - as gauge for the degree of severity of the DD infection - calculated for DD positive animals did not differ significantly between any of the groups at any of the examinations. 5. The “maximum weighted surface index” - as the rest gauge for the degree of severty of the DD infection - did not differ significantly at examination two and three between any of the groups. At the first examination, a significantly higher mean could be found in group A as compared to the control group (82; p = 0.006). At the 4th examination, a significantly lower mean could be found in the control group as compared to the vaccinated groups (22,5; p = 0.033). 6. No significant differences existed between any of the groups regarding treatments for claw diseases, applications of antibiotics and the proportion of culls related to DD. Conclusions: No prophylactic or therapeutic effect of herd-specific vaccination against digital dermatitis could be demonstrated in this controlled clinical trial. Inclusion of Treponema sp. antigen into the vaccine also did not cause effectiveness of the vaccine

Coarsening of Sand Ripples in Mass Transfer Models with Extinction

Coarsening of sand ripples is studied in a one-dimensional stochastic model, where neighboring ripples exchange mass with algebraic rates, $\Gamma(m) \sim m^\gamma$, and ripples of zero mass are removed from the system. For $\gamma < 0$ ripples vanish through rare fluctuations and the average ripples mass grows as \avem(t) \sim -\gamma^{-1} \ln (t). Temporal correlations decay as $t^{-1/2}$ or $t^{-2/3}$ depending on the symmetry of the mass transfer, and asymptotically the system is characterized by a product measure. The stationary ripple mass distribution is obtained exactly. For $\gamma > 0$ ripple evolution is linearly unstable, and the noise in the dynamics is irrelevant. For $\gamma = 1$ the problem is solved on the mean field level, but the mean-field theory does not adequately describe the full behavior of the coarsening. In particular, it fails to account for the numerically observed universality with respect to the initial ripple size distribution. The results are not restricted to sand ripple evolution since the model can be mapped to zero range processes, urn models, exclusion processes, and cluster-cluster aggregation.Comment: 10 pages, 8 figures, RevTeX4, submitted to Phys. Rev.

Chemical physics: The standing of a mature discipline

It is always promising and enticing to start a new editorial task in the scientific arena and the launch of the Chemistry Central Journal is no exception. The different thematic sections making up this journal are quite representative of the whole chemistry enterprise. However, one of them has a special relevance. In fact, Chemical Physics (CP) is the most general and it embodies a wide diversity of issues. Of particular importance at the launch of this groundbreaking new journal is the confidence of the Section Editor in BioMed Central (owners of Chemistry Central) as publishers, and from Chemistry Central to its Editorial Board. I feel deeply grateful for this new assignment and I hope to be able to perform a thorough job in editing this section. Below, I make my request to you as potential authors and reviewers

The orbital-specific virtual local triples correction: OSV-L(T)

A local method based on orbital specific virtuals (OSVs) for calculating the perturbative triples correction in local coupled cluster calculations is presented. In contrast to the previous approach based on projected atomic orbitals (PAOs), described by Schütz [J. Chem. Phys. 113, 9986 (2000)]10.1063/1.1323265, the new scheme works without any ad hoc truncations of the virtual space to domains. A single threshold defines the pair and triple specific virtual spaces completely and automatically. It is demonstrated that the computational cost of the method scales linearly with molecular size. Employing the recommended threshold a similar fraction of the correlation energy is recovered as with the original PAO method at a somewhat lower cost. A benchmark for 52 reactions demonstrates that for reaction energies the intrinsic accuracy of the coupled cluster with singles and doubles excitations and a perturbative treatment of triples excitations method can be reached by OSV-local coupled cluster theory with singles and doubles and perturbative triples, provided a MP2 correction is applied that accounts for basis set incompleteness errors as well as for remaining domain errors. As an application example the interaction energies of the guanine-cytosine dimers in the Watson-Crick and stacked arrangements are investigated at the level of local coupled cluster theory with singles and doubles and perturbative triples. Based on these calculations we propose new complete-basis-set-limit estimates for these interaction energies at this level of theory

Mid-IR observations of circumstellar disks -- Part III: A mixed sample of PMS stars and Vega-type objects

We present new mid-infrared spectra for a sample of 15 targets (1 FU Orionis object, 4 Herbig Ae stars, 5 T Tauri stars and 5 Vega type stars), obtained with the TIMMI2 camera at La Silla Observatory (ESO). Three targets are members of the beta Pic moving group (HD 155555, HD 181296 and HD 319139). PAH bands are observed towards the T Tauri star HD 34700 and the Herbig Ae star PDS 144 N. For HD 34700, the band profiles indicate processed PAHs. The spectrum of the Vega-type object eta Corvi (HD 109085), for which a resolved disk at sub-mm wavelengths is known, is entirely stellar between 8--13 micron. Similarly, no indication for circumstellar matter at mid-infrared wavelengths is found towards the Vega-like stars HD 3003, HD 80951, HD 181296 and, surprisingly, the T Tauri system HD 155555. The silicate emission features of the remaining eight sources are modelled with a mixture of silicates of different grain sizes and composition. Unprocessed dust dominates FU Ori, HD 143006 and CD-43 344. Large amorphous grains are the main dust component around HD 190073, HD 319139, KK Oph and PDS 144 S. Both small grains and crystalline dust is found for the Vega-type HD 123356, with a dominance of small amorphous grains. We show that the infrared emission of the binary HD 123356 is dominated by its late-type secondary, but optical spectroscopy is still required to confirm the age of the system and the spectral class of the companion. For most targets this is their first mid-infrared spectroscopic observation. We investigate trends between stellar, disk and silicate properties and confirm correlations of previous studies. Several objects present an exciting potential for follow-up high-resolution disk studies.Comment: Accepted for publication in A&

Imaging magnonic frequency multiplication in nanostructured antidot lattices

Frequency multiplication is an essential part of electronics and optics which led to numerous indispensable applications. In this paper, we utilize a combination of scanning transmission x ray microscopy and micromagnetic simulations to directly image magnonic frequency multiplication by means of dynamic real space magnetization measurements. We experimentally demonstrate frequency multiplication up to the seventh order, which enables the generation of nanoscale spin waves at 6GHz with excitation frequencies of less than 1GHz. Good agreement between the experiment and micromagnetic simulations allows us to build a micromagnetic model capable of predicting conversion efficiencies and multiplexing capabilities of the system. Furthermore, simulations reveal that more than two rows of antidots do not increase the conversion efficiency substantially. By enabling magnonic multiplexing with low input frequencies while not exceeding the size of a few microns, the device will lead to numerous applications, further advancing the capabilities of magnonic data transmissio

Garden varieties: how attractive are recommended garden plants to butterflies?

One way the public can engage in insect conservation is through wildlife gardening, including the growing of insect-friendly flowers as sources of nectar. However, plant varieties differ in the types of insects they attract. To determine which garden plants attracted which butterflies, we counted butterflies nectaring on 11 varieties of summer-flowering garden plants in a rural garden in East Sussex, UK. These plants were all from a list of 100 varieties considered attractive to British butterflies, and included the five varieties specifically listed by the UK charity Butterfly Conservation as best for summer nectar. A total of 2659 flower visits from 14 butterfly and one moth species were observed. We performed a principal components analysis which showed contrasting patterns between the species attracted to Origanum vulgare and Buddleia davidii. The “butterfly bush” Buddleia attracted many nymphalines, such as the peacock, Inachis io, but very few satyrines such as the gatekeeper, Pyronia tithonus, which mostly visited Origanum. Eupatorium cannibinum had the highest Simpson’s Diversity score of 0.75, while Buddleia and Origanum were lower, scoring 0.66 and 0.50 respectively. No one plant was good at attracting all observed butterfly species, as each attracted only a subset of the butterfly community. We conclude that to create a butterfly-friendly garden, a variety of plant species are required as nectar sources for butterflies. Furthermore, garden plant recommendations can probably benefit from being more precise as to the species of butterfly they attract

SPITZER survey of dust grain processing in stable discs around binary post-AGB stars

Aims: We investigate the mineralogy and dust processing in the circumbinary discs of binary post-AGB stars using high-resolution TIMMI2 and SPITZER infrared spectra. Methods: We perform a full spectral fitting to the infrared spectra using the most recent opacities of amorphous and crystalline dust species. This allows for the identification of the carriers of the different emission bands. Our fits also constrain the physical properties of different dust species and grain sizes responsible for the observed emission features. Results: In all stars the dust is oxygen-rich: amorphous and crystalline silicate dust species prevail and no features of a carbon-rich component can be found, the exception being EPLyr, where a mixed chemistry of both oxygen- and carbon-rich species is found. Our full spectral fitting indicates a high degree of dust grain processing. The mineralogy of our sample stars shows that the dust is constituted of irregularly shaped and relatively large grains, with typical grain sizes larger than 2 micron. The spectra of nearly all stars show a high degree of crystallinity, where magnesium-rich end members of olivine and pyroxene silicates dominate. Other dust features of e.g. silica or alumina are not present at detectable levels. Temperature estimates from our fitting routine show that a significant fraction of grains must be cool, significantly cooler than the glass temperature. This shows that radial mixing is very efficient is these discs and/or indicates different thermal conditions at grain formation. Our results show that strong grain processing is not limited to young stellar objects and that the physical processes occurring in the discs are very similar to those in protoplanetary discs.Comment: 22pages, 50 figures (in appendix), accepted for A&