- Email: [email protected]
Characterization of Cases of Ovine Atypical Scrapie in Slovenia
143:4, 2010
ESVP/ECVP Proceedings 2010
327
P21
P22
INTERACTIONS OF VIRULENT AND AVIRULENT YERSINIA RUCKERI STRAINS WITH ISOLATED GILL ARCHES AND INTESTINAL EXPLANTS OF RAINBOW TROUT (ONCORHYNCHUS MYKISS, WALBAUM) G. Vercauteren, E. Tobback, K. Hermans, A. Decostere, W. Vandenbrouck and K. Chiers Ghent University, Belgium Introduction: The portal of entry of Yersinia ruckeri infection in salmonids has not yet been fully elucidated. We have studied the interactions of Y. ruckeri with gills and gut explants using standardized perfusion models. Materials and Methods: Avirulent and virulent strains of Y. ruckeri (approximately 108 CFU/ml) were added to isolated perfused gill and gut explants. The adhesion and invasion capacity were determined by bacteriological examination of tissues and efferent perfusion fluid, respectively. Histology and immunohistochemistry were performed to visualize adherent and invading bacteria. Results: Bacteriological examination indicated that both virulent and avirulent Y. ruckeri isolates adhered to and invaded both tissues without significant differences. Histopathological changes were not observed in the tissues. Y. ruckeri was found in the mucus of the primary and secondary lamellae, closely associated with the gill epithelium and with some invading in the lamina propria. In gut, Y. ruckeri bacteria were present in the crypts, attached to the villi, within the epithelial layer of gut segments and few were within the lamina propria. Conclusions: Y. ruckeri colonizes and invades the gills and gut tissue of rainbow trout (Oncorhynchus mykiss, Walbaum), indicating that both organs can be the portal of entry of the infection.
CHARACTERIZATION OF CASES OF OVINE ATYPICAL SCRAPIE IN SLOVENIA P. Juntes *, P.J. Zabavnik *, M. Cotman * and I. Ambrozicy *University of Ljubljana, Veterinary Faculty and yMAFF, Veterinary Administration of the Republic of Slovenia, Slovenia Introduction: Atypical scrapie is a form of scrapie first described in sheep in 1998 in Norway (NOR 98) and later in a number of other countries, including very recently in New Zealand and Australia. The first cases of atypical scrapie were found in Slovenia in 2010 and are documented here. Materials and Methods: Brain samples were collected during routine monitoring for TSEs from sheep that died or were killed on farms. Atypical cases were identified by use of the rapid test. Further characterization was by application of three additional rapid tests, histopathology, immunohistochemistry, genotyping and a BSE/TSE discriminatory test. Results: All tests that necessitated use of proteinase K digestion were negative. BSE and classical scrapie were excluded, but immunohistochemistry revealed patterns characteristic for NOR 98 atypical scrapie. Several cases were found in which there was different atypical immunolabelling of the cerebellum. These were not conclusively confirmed for TSE after additional examinations in the CRL for TSE. Conclusions: Atypical scrapie can be expected in small ruminants in all countries, but detection requires appropriate testing. Slovenian cases of atypical scrapie are similar to NOR 98; however, other forms of atypical scrapie may appear.
P23
P24
SYSTEMIC VENOUS THROMBOSIS IN BABESIA CANIS CANIS INFECTION OF TWO DOGS A. Beck *, R. Beck y, V. Mrljak *, A. Gudan Kurilj *, B. Artukovic * and Z. Grabarevic* *Veterinary Faculty, University of Zagreb and yDepartment for Bacteriology and Parasitology, Croatian Veterinary Institute, Zagreb, Croatia Introduction: A male poodle (case 1) and female mixed breed dog (case 2) were treated with imidocarb dipropionate for babesiosis. Clinical signs in case 1 included anaemia, jaundice, renal failure, bilirubinaemia and increased serum amylase. Case 2 had multiple organ dysfunction syndrome with leucocytosis, thrombocytopenia and bilirubinaemia. After initial improvement both dogs died, 12 and 6 days after the beginning of treatment, respectively. Materials and Methods: Necropsy examination was performed and tissue samples were collected for routine histopathology. DNA was extracted from both spleens for confirmation with PCR and subsequent sequencing. Results: Apart from gross findings distinctive for haemolytic anaemia in canine babesiosis (e.g. haemoglobinuric nephrosis), thrombosis of the splenic vein with multiple infarctions was present in both cases. In case 2, multifocal necrotizing dermatitis was present. Microscopical examination revealed thrombi in the spleen, pancreas and tongue in case 1 and in the spleen, skin and oesophagus in case 2. Sequence analysis of the PCR fragment revealed a sequence 100% identical to Babesia canis canis in both cases. Conclusions: Haemolysis, disseminated intravascular coagulation and vascular damage consistently occur in B. canis canis infections. ATIII loss through damaged glomeruli due to haemoglobinuric nephrosis is likely to have led to venous thrombosis in these cases.
LACK OF ASSOCIATION BETWEEN SCRAPIE GENETIC SELECTION AND MAEDI-VISNA VIRUS ANTIBODY TITRES erez *, B. Amorena z, E. Salazar *, E. Berriatua y, M. P J.J. Badiola * and L. Luj an* *University of Zaragoza, yUniversity of Murcia and z UPNA/CSIC, Spain Introduction: Scrapie and maedi-visna (MV) are chronic and fatal small ruminant infections. Antibody detection against MV virus (MVV) by ELISA is used for diagnosis of MV infection within a flock and for implementation of control and eradication programs. Resistance and susceptibility to scrapie is related to three main codons of the PRNP gene, namely 136, 154 and 171. Selecting breeding favouring scrapie resistance based on the individual genotype has been performed since 2002. This genetic selection could have unexpected effects in other conformational, reproductive or disease-related traits. Materials and Methods: Individual data were obtained from 10,602 Rasa Aragonesa sheep from 17 flocks (flock seroprevalence ranging between 23.7 and 87.4%). Using multifactorial statistical analysis (SAS) we studied the possible relationship between MVV antibody titre and the different groups of resistance or susceptibility to scrapie. Results: The MVV serum antibody titre from genetically resistant animals was not statistically significantly different from genetically susceptible sheep. Conclusions: Genetic selection for resistance to scrapie does not influence individual MVV serum antibody titres and has no impact in ELISA-based, MVV control and eradication programmes.
ESVP/ECVP Proceedings 2010
327
P21
P22
INTERACTIONS OF VIRULENT AND AVIRULENT YERSINIA RUCKERI STRAINS WITH ISOLATED GILL ARCHES AND INTESTINAL EXPLANTS OF RAINBOW TROUT (ONCORHYNCHUS MYKISS, WALBAUM) G. Vercauteren, E. Tobback, K. Hermans, A. Decostere, W. Vandenbrouck and K. Chiers Ghent University, Belgium Introduction: The portal of entry of Yersinia ruckeri infection in salmonids has not yet been fully elucidated. We have studied the interactions of Y. ruckeri with gills and gut explants using standardized perfusion models. Materials and Methods: Avirulent and virulent strains of Y. ruckeri (approximately 108 CFU/ml) were added to isolated perfused gill and gut explants. The adhesion and invasion capacity were determined by bacteriological examination of tissues and efferent perfusion fluid, respectively. Histology and immunohistochemistry were performed to visualize adherent and invading bacteria. Results: Bacteriological examination indicated that both virulent and avirulent Y. ruckeri isolates adhered to and invaded both tissues without significant differences. Histopathological changes were not observed in the tissues. Y. ruckeri was found in the mucus of the primary and secondary lamellae, closely associated with the gill epithelium and with some invading in the lamina propria. In gut, Y. ruckeri bacteria were present in the crypts, attached to the villi, within the epithelial layer of gut segments and few were within the lamina propria. Conclusions: Y. ruckeri colonizes and invades the gills and gut tissue of rainbow trout (Oncorhynchus mykiss, Walbaum), indicating that both organs can be the portal of entry of the infection.
CHARACTERIZATION OF CASES OF OVINE ATYPICAL SCRAPIE IN SLOVENIA P. Juntes *, P.J. Zabavnik *, M. Cotman * and I. Ambrozicy *University of Ljubljana, Veterinary Faculty and yMAFF, Veterinary Administration of the Republic of Slovenia, Slovenia Introduction: Atypical scrapie is a form of scrapie first described in sheep in 1998 in Norway (NOR 98) and later in a number of other countries, including very recently in New Zealand and Australia. The first cases of atypical scrapie were found in Slovenia in 2010 and are documented here. Materials and Methods: Brain samples were collected during routine monitoring for TSEs from sheep that died or were killed on farms. Atypical cases were identified by use of the rapid test. Further characterization was by application of three additional rapid tests, histopathology, immunohistochemistry, genotyping and a BSE/TSE discriminatory test. Results: All tests that necessitated use of proteinase K digestion were negative. BSE and classical scrapie were excluded, but immunohistochemistry revealed patterns characteristic for NOR 98 atypical scrapie. Several cases were found in which there was different atypical immunolabelling of the cerebellum. These were not conclusively confirmed for TSE after additional examinations in the CRL for TSE. Conclusions: Atypical scrapie can be expected in small ruminants in all countries, but detection requires appropriate testing. Slovenian cases of atypical scrapie are similar to NOR 98; however, other forms of atypical scrapie may appear.
P23
P24
SYSTEMIC VENOUS THROMBOSIS IN BABESIA CANIS CANIS INFECTION OF TWO DOGS A. Beck *, R. Beck y, V. Mrljak *, A. Gudan Kurilj *, B. Artukovic * and Z. Grabarevic* *Veterinary Faculty, University of Zagreb and yDepartment for Bacteriology and Parasitology, Croatian Veterinary Institute, Zagreb, Croatia Introduction: A male poodle (case 1) and female mixed breed dog (case 2) were treated with imidocarb dipropionate for babesiosis. Clinical signs in case 1 included anaemia, jaundice, renal failure, bilirubinaemia and increased serum amylase. Case 2 had multiple organ dysfunction syndrome with leucocytosis, thrombocytopenia and bilirubinaemia. After initial improvement both dogs died, 12 and 6 days after the beginning of treatment, respectively. Materials and Methods: Necropsy examination was performed and tissue samples were collected for routine histopathology. DNA was extracted from both spleens for confirmation with PCR and subsequent sequencing. Results: Apart from gross findings distinctive for haemolytic anaemia in canine babesiosis (e.g. haemoglobinuric nephrosis), thrombosis of the splenic vein with multiple infarctions was present in both cases. In case 2, multifocal necrotizing dermatitis was present. Microscopical examination revealed thrombi in the spleen, pancreas and tongue in case 1 and in the spleen, skin and oesophagus in case 2. Sequence analysis of the PCR fragment revealed a sequence 100% identical to Babesia canis canis in both cases. Conclusions: Haemolysis, disseminated intravascular coagulation and vascular damage consistently occur in B. canis canis infections. ATIII loss through damaged glomeruli due to haemoglobinuric nephrosis is likely to have led to venous thrombosis in these cases.
LACK OF ASSOCIATION BETWEEN SCRAPIE GENETIC SELECTION AND MAEDI-VISNA VIRUS ANTIBODY TITRES erez *, B. Amorena z, E. Salazar *, E. Berriatua y, M. P J.J. Badiola * and L. Luj an* *University of Zaragoza, yUniversity of Murcia and z UPNA/CSIC, Spain Introduction: Scrapie and maedi-visna (MV) are chronic and fatal small ruminant infections. Antibody detection against MV virus (MVV) by ELISA is used for diagnosis of MV infection within a flock and for implementation of control and eradication programs. Resistance and susceptibility to scrapie is related to three main codons of the PRNP gene, namely 136, 154 and 171. Selecting breeding favouring scrapie resistance based on the individual genotype has been performed since 2002. This genetic selection could have unexpected effects in other conformational, reproductive or disease-related traits. Materials and Methods: Individual data were obtained from 10,602 Rasa Aragonesa sheep from 17 flocks (flock seroprevalence ranging between 23.7 and 87.4%). Using multifactorial statistical analysis (SAS) we studied the possible relationship between MVV antibody titre and the different groups of resistance or susceptibility to scrapie. Results: The MVV serum antibody titre from genetically resistant animals was not statistically significantly different from genetically susceptible sheep. Conclusions: Genetic selection for resistance to scrapie does not influence individual MVV serum antibody titres and has no impact in ELISA-based, MVV control and eradication programmes.