Polyarthritis caused by Erysipelothrix rhusiopathiae in three Austrian sheep flocks - diagnosis, treatment and management measures.

INTRODUCTION: Polyarthritis caused by Erysipelothrix rhusiopathiae is a well-known disease in pigs, and ovine erysipelas infection also commonly affects two-to-six month-old lambs. This report describes case histories of three sheep flocks where lambs exhibited swollen joints and lameness. Special emphasis was given to clinical and diagnostic imaging findings, synovia sampling and the treatment regime. Lambs with only mild lameness, liquid serofibrinous joint effusion and lambs showing no bone involvement, as revealed by ultrasonography or radiography, were treated with systemically administered antibiotics selected from results of antimicrobial susceptibility testing of E. rhusiopathiae isolated from synovial samples, and non-steroidal anti-inflammatory drugs. Lambs with severe lameness and severely swollen joints were euthanized, and routine necropsy was undertaken with a focus on the joints. Further, a herd-specific autogenous vaccine was produced by a specialized laboratory. In conclusion, E. rhusiopathiae infection should be considered as a differential diagnosis in herds associated with lameness and polyarthritis in lambs aged between two up to 17 months.

INTRODUCTION: La polyarthrite causée par Erysipelothrix rhusiopathiae est une maladie bien connue chez le porc. Chez les ovins, l'infection touche le plus souvent les agneaux âgés de deux à six mois. Ce rapport de cas décrit trois troupeaux de moutons où des agneaux présentaient des articulations enflées et une boiterie. Un accent particulier a été mis sur la clinique, les résultats de l'imagerie diagnostique, les prélèvements de synovie et le mode de traitement. Les agneaux présentant uniquement une légère boiterie, des épanchements articulaires séro-fibrineux et ceux ne présentant pas d'atteinte osseuse, révélée par échographie ou radiographie, ont été traités avec des antibiotiques administrés par voie systémique, sélectionnés à partir des résultats de la sensibilité d'E. Rhusiopathiae isolé sur les échantillons synoviaux, ainsi qu'avec des anti-inflammatoires non stéroïdiens. Les agneaux présentant une boiterie sévère et des articulations gravement enflées ont été euthanasiés et une autopsie de routine a été réalisée avec un accent particulier mis sur les articulations. De plus, un vaccin autogène spécifique au troupeau a été produit par un laboratoire. En conclusion, l'infection à E. rhusiopathiae doit être considérée comme un diagnostic différentiel dans les troupeaux où l'on constate des boiteries et des polyarthrites chez les agneaux âgés de 2 à 17 mois.

[Congenital flexural deformity in 93 calves - appearance, treatment techniques and results of pedigree analysis]. / Sehnenstelzfuß bei 93 Kälbern ­ Erscheinungsformen, Behandlungs­methoden und Ergebnis einer Pedigreeanalyse.

INTRODUCTION: Contracture of the flexor tendons (CFT) is very common in calves and it is usually diagnosed within the first few days after birth (congenital flexural deformity). However, CFT can appear even in older calves caused by chronic pain. The aetiology of CFT is still unknown. In this study, the distribution of sex, age, breed, the severity of flexural deformity, concurrent presence of other diseases, applied treatment methods for flexural deformity, and the outcome of calves with CFT, which were examined at the University Clinic for Ruminants in Vienna from 2001 to 2016, were evaluated retrospectively. 93 calves were admitted with CFT in the observation period. 70 (75.3%) calves were male and 78 (83.9%) of the affected animals were Simmental calves. The age of calves with CFT varied from one day to 41 days. Twenty-six calves suffered exclusively from CFT, and CFT was diagnosed as an additional finding in 67 calves. 91 animals (97.8%) showed CFT on the front limbs, 79 of them (84.9%) on both front limbs. The distribution of the severity scores was as follows: 69 calves (74.2%) had score 1, 17 calves (18.3%) had score 2, three calves (3.2%) had score 3. Three additional calves (3.2%) had a score 1 CFT on one front limb and a score 2 CFT on the other front limb, and one additional calf showed all three scores on both front limbs and one hind limb. 69 patients (74.2%) could be discharged with a significant improvement in CFT after treatment and 24 calves (25.8%) had to be euthanized due to other severe diseases. The results of the applied pedigree analysis do not show that a single gene mutation is the cause for the development of CFT, but rather a complex hereditary pattern has to be assumed. Depending on the severity of CFT and the presence of other concurrent diseases, an early and consistent therapy has to be carried out to achieve the highest possible success. Since animals with CFT are usually restricted in their movement, sufficient colostrum intake must be ensured within the first hours of life.

INTRODUCTION: La contracture des tendons fléchisseurs (CTF) est très fréquente chez les veaux et elle est généralement diagnostiquée dans les premiers jours suivant la naissance (malformation congénitale en flexion). Cependant, la CTF peut apparaître même chez les veaux plus âgés en raison d'une douleur chronique. L'étiologie de la CTF est encore inconnue. Dans cette étude, la répartition du sexe, de l'âge, de la race, la sévérité de la déformation en flexion, la présence concomitante d'autres maladies, les méthodes de traitement appliquées pour la déformation en flexion et les résultats chez les veaux atteints de CTF, examinés à la Clinique universitaire des ruminants de Vienne de 2001 à 2016, ont été évalués rétrospectivement. 93 veaux ont été admis avec une CTF au cours de la période d'observation. 70 veaux (75,3%) étaient des mâles et 78 (83,9%) des animaux atteints étaient des veaux Simmental. L'âge des veaux atteints de CTF variait d'un jour à 41 jours. Vingt-six veaux ont souffert exclusivement de CTF et une CTF a été diagnostiquée comme une découverte supplémentaire chez 67 veaux. 91 animaux (97,8%) présentaient une CTF sur les membres antérieurs, dont 79 (84,9%) sur les deux membres antérieurs. La répartition des scores de gravité était la suivante: 69 veaux (74,2%) ont obtenu un score de 1, 17 veaux (18,3%) ont obtenu un score de 2, trois veaux (3,2%) ont obtenu un score de 3. Trois autres veaux (3,2%) ont obtenu un score 1 CTF sur un membre antérieur et un score de 2 CTF sur l'autre membre antérieur et un veau présentait les trois scores sur les deux membres antérieurs et un membre postérieur. 69 patients (74,2%) ont pu quitter l'hôpital avec une amélioration significative de la CTF après le traitement et 24 veaux (25,8%) ont dû être euthanasiés en raison d'autres maladies graves. Les résultats de l'analyse du pedigree ne montrent pas qu'une seule mutation du gène soit la cause du développement de la CTF, mais plutôt qu'un schéma héréditaire complexe doit être supposé. En fonction de la gravité de la CTF et de la présence d'autres maladies concomitantes, un traitement précoce et cohérent doit être mis en œuvre pour obtenir le meilleur succès possible. Comme les mouvements des animaux atteints de CTF sont généralement limités, un apport suffisant de colostrum doit être garanti dès les premières heures de la vie.

Chemical reactivity of Ni-Rh nanowires.

The properties of bimetallic Ni-Rh nanowires, fabricated by decorating the steps of vicinal Rh(111) surfaces by stripes of self-assembled Ni adatoms, have been probed by STM, photoemission, and ab initio density functional theory calculations. These Ni-Rh nanowires have specific electronic properties that lead to a significantly enhanced chemical reactivity towards oxygen. As a result, the Ni-Rh nanowires can be oxidized exclusively, generating novel quasi-one-dimensional oxide structures.

Reactivity of V2O3(0001) surfaces: molecular vs dissociative adsorption of water.

The adsorption of water on V2O3(0001) surfaces has been investigated by thermal desorption spectroscopy, high-resolution electron energy loss spectroscopy, and X-ray photoelectron spectroscopy with use of synchrotron radiation. The V2O3(0001) surfaces have been generated in epitaxial thin film form on a Rh(111) substrate with three different surface terminations according to the particular preparation conditions. The stable surface in thermodynamic equilibrium with the bulk is formed by a vanadyl (VO) (1x1) surface layer, but an oxygen-rich (radical3xradical3)R30 degrees reconstruction can be prepared under a higher chemical potential of oxygen (microO), whereas a V-terminated surface consisting of a vanadium surface layer requires a low microO, which can be achieved experimentally by the deposition of V atoms onto the (1x1) VO surface. The latter two surfaces have been used to model, in a controlled way, oxygen and vanadium containing defect centres on V2O3. On the (1x1) V=O and (radical3xradical3)R30 degrees surfaces, which expose only oxygen surface sites, the experimental results indicate consistently that the molecular adsorption of water provides the predominant adsorption channel. In contrast, on the V-terminated (1/radical3x1/radical3)R30 degrees surface the dissociation of water and the formation of surface hydroxyl species at 100 K is readily observed. Besides the dissociative adsorption a molecular adsorption channel exists also on the V-terminated V2O3(0001) surface, so that the water monolayer consists of both OH and molecular H2O species. The V surface layer on V2O3 is very reactive and is reoxidised by adsorbed water at 250 K, yielding surface vanadyl species. The results of this study indicate that V surface centres are necessary for the dissociation of water on V2O3 surfaces.

Experimental and theoretical study of a surface stabilized monolayer phase of nickel oxide on Pd(100).

A surface stabilized monolayer phase of nickel oxide, c(4 x 2)-Ni(3)O(4), has been found to grow epitaxially under reactive deposition conditions on Pd(100), in the presence of other adsorbed phases and in competition with them. High-quality scanning tunneling microscopy data are reported and discussed, including a detailed analysis of the defects and of the border morphology of this new phase. The data are discussed in the light of ab initio simulations of the electronic, energetic, and geometric properties of such a phase. A hybrid-exchange density functional theory approach has been used, and a slab model is adopted where palladium is simulated by a thin film covered on both sides by regular epilayers. A growth model has been developed that explains both the unusual stoichiometry of the phase and the observed defects.

Planar vanadium oxide clusters: two-dimensional evaporation and diffusion on Rh(111).

The formation of novel vanadium oxide cluster molecules by oxidative two-dimensional evaporation from vanadium oxide nanostructures is reported on a Rh(111) metal surface. The structure and stability of the planar V6O12 clusters and the physical origin of their 2D evaporation process have been elucidated by high-resolution scanning tunneling microscopy (STM) and ab initio density functional theory calculations. The surface diffusion of the clusters has been followed in elevated-temperature STM experiments, and the diffusion parameters have been extracted, indicating diffusion by hopping of the entire surface stabilized cluster units.

Reversible dynamic behavior in catalyst systems: oscillations of structure and morphology.

Exposing vanadium oxide nanoparticles on a Pd(111) surface to reducing conditions is shown to cause a spreading of the oxide over the metal until a reduced oxide phase covers the entire surface. Reoxidation reverses this process and oxide island structures and bare metal patches are reestablished. The physical origin of this wetting-dewetting process is revealed at the atomic level by in situ variable-temperature scanning tunneling microscopy and in terms of a surface oxide phase stability diagram, as calculated by density functional theory as a function of the chemical potential of oxygen and the vanadium concentration.