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Background: Mycobacterium avium subspecies paratuberculosis (MAP) is the cause of paratuberculosis. MAP infections have not been reliably detected in dogs, but a reemerging debate about the link between MAP and Crohn's disease has renewed interest about the occurrence of MAP in pets. Hypothesis: This study was undertaken to examine canine intestinal biopsies for the presence of MAP-specific DNA. Animals: Forty-two dogs with chronic vomiting, diarrhea, or both; and 14 dogs with no gastrointestinal disease. Methods: All dogs with signs of gastrointestinal disease had a standard work-up for chronic gastrointestinal disease. Endoscopically obtained intestinal biopsies were submitted for histopathologic and molecular investigations. Biopsies were screened for MAP-specific DNA by 3 polymerase chain reaction (PCR) methods (nested, seminested, and triplex real-time PCR). Samples from control dogs were obtained during necropsy. Results: Histopathology of the biopsies was indicative of inflammatory bowel disease (IBD) in 17 and neoplasia in 6 dogs. Six dogs showing nonspecific changes responded to diet and were classified as having food-responsive enteropathy. In 13 dogs a final diagnosis was not established. MAP-specific DNA was detected and confirmed by sequencing in 8 dogs (19%). These dogs were diagnosed with food-responsive enteropathy (n = 3), IBD (n = 2), and open diagnosis (n = 3). MAP-specific DNA was not detected in dogs with no gastrointestinal disease. Conclusions and clinical importance: MAP-specific DNA was detected in approximately one fifth of dogs with chronic gastrointestinal disease and might play a role as a pathogenic agent. Apart from animal welfare, the zoonotic aspect warrants further studies addressing the viability of MAP organism in canine intestinal biopsies by culture.

To investigate the deformation characteristics of billets with liquid core during soft reduction and to clarify the correlation between internal cracks and deformation of the billet in the mushy zone, a fully coupled thermo-mechanical Finite Element Model was developed in ABAQUS, furthermore, casting and soft reduction tests were carried out in a laboratory strand casting machine. During soft reduction the temperature distribution, the stress and strain states in the billet were calculated, the deformation characteristics of the billet during soft reduction were determined and the relation between internal cracks and equivalent plastic strain as well as maximal principal stress was analysed. The results show that tensile stresses can develop in the mushy zone during soft reduction and the equivalent strain nearby the Zero Ductility Temperature (ZDT) increases with a decreasing solid fraction. Internal cracks can be initiated when the accumulated strain exceeds the critical strain and /or the applied tensile stress exceeds the critical fracture stress during solidification. In addition, the factors (reduction efficiency and internal cracks) that should be considered to determine the optimal parameter for the soft reduction were established.

Centre segregation is the main reason for cup fracture during drawing of high carbon wire rod. Therefore, producing continuously cast billets with very low centre segregation is an important objective. The soft reduction technology is considered to be an effective method to minimize centre segregation. In order to clarify the effectiveness of soft reduction on internal quality of high carbon steel billets, soft reduction was applied in a laboratory casting machine while the solid fraction in the core area of billets was varied. A coupled temperature/displacement Finite Element model was developed to calculate the solid fraction with the commercial software ABAQUS. Centre segregation, centre porosity, homogeneity of elements and equiaxed crystal zone were obviously improved by applying soft reduction, especially when the solid fraction was about 0.9.

The high temperature properties of steels depend on the solidification parameters and the formation parameters of manganese sulphide precipitates. Therefore, the occurrence of MnS precipitations in relation to primary and secondary microstructures was studied for different steel grades with a primary delta-ferritic solidification or a primary austenitic solidification. The liquidus and solidus temperatures as well as the bγ-transformation temperature were calculated thermodynamically and measured by a DTA analysis in order to describe the solidification and transformation temperature range. The MnS formation temperature was calculated thermodynamically and compared to the results of SEM/EDX investigations on fracture surfaces of hot tensile specimens torn at different temperatures after in situ melting and controlled solidification. A special focus of these investigations was the location of MnS precipitates in relation to the primary and secondary grain boundaries. To explain the results, calculations were carried out taking into account the supersaturation of manganese and sulphur during the solidification in residual melt on the primary grain boundaries.

Thixoforming is a new manufacturing technology which has been widely investigated for aluminium alloys. The thixoformability of steel and especially the impact of different pre-processing is subject of this paper. For thethixoforming process it is of special interest to obtain the required fraction liquid content between 20 and 40 %, a globulitic microstructure and low process temperatures. Therefore, steel primary material from three different processing routes was compared. The primary materials are rolled bars, laboratory cast billets and laboratory cast billets with liquid core reduction. The melting behaviour of the different materials was investigated by using Differential Thermal Analysis (DTA). Furthermore the materials were reheated into the solid-liquid range and quenched to monitor the development of the microstructure. No significant differences between the three different pre-processing routes could be determined with regard to thixoforming. Thus it seems possible to start thixoforming with as-cast primary material.

Der aktuelle Stand der Technik zum Verbund- und Verankerungsverhalten von Spannstahl im sofortigen Verbund und die daraus abgeleiteten Bemessungsregeln fur DIN 1045-1 werden erlautert und an Bemessungsbeispielen verdeutlicht. Die Regelungen zum Nachweis der Verankerung weichen zum Teil erheblich von den bisherigen Nachweisverfahren nach DIN 4227 ab. Das neue Bemessungskonzept gilt fur alle Vorspanngrade.

The identification of species origin of meat represents a considerable problem for food and animal feed analysis. In the present study a PCR-mediated method for the detection of dog and cat meat was developed. For this the cytochrome b gene sequence of both species was analyzed by restriction fragment length polymorphism (RFLP) analysis. The use of the restriction enzymes ALU I and Hae III yielded specific restriction profiles characteristic for each species. The meat of both species could additionally be differentiated with species-specific aligonucleotide primers based on specific parts of the cytOchrome b gene sequences characteristic for dog, and cat. The use of these oliginucleotide primers allowed a direct identification of dog and cat meat in meat mixtures even after heat treatment.

To enforce labeling regulations in the authentication of ostrich meat, it might be of importance to evaluate a method to identify the ostrich meat. A restriction site of the polymerase chain reaction (PCR) product has been used for the specific identification of ostrich meat. In the present study the part of the gene encoding cytochrome b was amplified and sequenced. The digestion of the PCR products using specific estriction enzymes Hae III, Hinf I, Rsa I, and Tru 91 were used to yield specific restriction profiles that allowed a direct identification of ostrich meat in raw and heat-treated samples from meat of other food animal species.

To enforce labeling regulations in the authentication of snail species it might be of importance to use nonmorphological methods. Snail meat of 2 species was analyzed by restriction fragment length polymorphism (RFLP) of the genes encoding mitochondrial 12S rRNA and 16S rRNA. Digestion of the polymerase chain reaction (PCR) products of 12S rRNA with the endonucleases Afi III, Dra I and Sty I, and the 16S rRNA PCR product with the endonucleases Nsp I, Sfu I and Taq I, yielded specific banding patterns characteristic for Helix pomatia and Helix lucorum. The meat of both species could additionally be differentiated with species-specific oligonucleotide primers based on 16S rRNA gene sequences characteristic for both species. Pour renforcer les normes d'etiquettage dans l'authentification des especes d'escargots, des methodes non morphologiques peuvent etre utiles. Cette etude evalue des methodes RFLP-PCR (polymorphisme de longueur de fragment de restriction - reaction en chaine par polymerase) pour l'identification et la differenciation de Helix pomatia et H. lucorum. L'analyse est basee sur 3 regions d'ADN mitochondrial dans le gene rRNA 12S, rRNA 16S et le cytochrome b. Les amorces specifiques a l'espece dans le gene rRNA 16S sont determinees et evaluees.