An 18-year-old Morgan mare was presented to the Veterinary Medical Teaching Hospital, University of Illinois, with a 10-day history of watery diarrhea, depression, and dysphagia. On admission, the animal was severely dehydrated, depressed, and unable to swallow and had no clinical signs of diarrhea. The respiratory and heart rate and body temperature were within normal limits. Following fluid therapy, the mare developed severe watery diarrhea and continued to be depressed, incoordinated, and dysphagic. The animal died on the fourth day after admission and was sent to the Laboratories of Veterinary Diagnostic Medicine for necropsy. Gross postmortem findings were consistent with an acute cerebral infarction in the right cerebral hemisphere, an acute necrotizing typhlocolitis, multifocal petechial and ecchymotic hemorrhages, enlarged and congested pars intermedia of the pituitary gland, and marked bilateral adrenocortical hyperplasia with multifocal areas of necrosis and hemorrhage. Histologic evaluation of the affected brain demonstrated an area of coagulative necrosis of the gray matter, with hemorrhage, vasculitis, and thrombosis. There were many fungal hyphae 3.5-6.0 microm, pale basophilic, septate, and occasionally branching at 45 degrees present in the arterial walls and throughout the necrotic tissue. Immunohistochemical analysis revealed Aspergillus niger as the etiologic agent responsible for the mycotic vasculitis and infarction in the brain. Bacteria culture and immunohistochemical staining of the colon and cecum failed to demonstrate specific pathogens.

Estimación de la sensibilidad y especificidad de dos pruebas diagnósticas para la detección de Mycoplasma suis en Argentina utilizando un modelo bayesianoEstimation of the sensitibity and specificity of two Mycoplasma suis diagnostic tests in Argentina using a Bayesian model SUMMARYA prerequisite for understanding the impact of Mycoplasma suis infection on pig production and its epidemiological dynamics in infected regions, is the development of diagnostic techniques to discriminate infected from non-infected populations. The objectives of this study were to confirm the presence of M. suis infection in Argentina, and to estimate the sensitivity and specificity of both an Indirect Immunofluorescent Assay (IIFA) and a Polymerase Chain Reaction (PCR) for the detection of the agent. Blood was collected from 282 pigs belonging to 38 farms. Sensitivity (Se) and specificity (Sp) of the tests were estimated using a Bayesian model for conditional dependant results and without assuming a gold standard. PCR was estimated to be a highly sensitive (Se = 0.982, CI95% = 0.942-0.997) and highly specific (Sp = 0.946; CI95% = 0.873-0.984) method for diagnosis of M. suis infection in the assessed population. A significantly (P < 0.05) lower sensitivity (Se = 0.682, CI95% = 0.615-0.753) and specificity (Sp = 0.787, CI95% = 0.712-0.863) was estimated for the IIFA. Correlation among tests results was low, both for infected (R = 0.010, CI95% = -0.118-0.195) and non-infected (R = 0.049, CI95% = -0.133-0.407) individuals. The posterior estimate of the probability of finding an infected animal in the study population, which approximates the prevalence of the disease in the sampled animals, was 0.622 (CI95% = 0.554-0.684). The study was successful in confirming the presence of M. suis infection in Argentina and the accuracy of the PCR for the detection of the agent.Palabras clave: Mycoplasma suis, PCR, prueba de inmunofluorescencia indirecta, cerdos.

Botulism in cattle has been associated with the ingestion of contaminated carrion or forages.  This report describes the clinical signs and diagnostic approaches in three outbreaks of botulism in cattle where Clostridium botulinum Type B organisms were identified in each herd and specific toxin detected in the forage of one herd. In each of these outbreaks Type B organisms wereisolated from the silage which may have been improperly fermented. The key factor may be the lack of adequate fermentation to reach a low pH, thus inhibiting sporulation and toxin production by Clostridium botulinum. Botulinum organisms were also isolated from the rumen contents and feces of affected cattle which help confirm the diagnosis because normal cattle do not have botulinum organisms in the gastrointestinal contents. Mouse toxicity and neutralization testing was performed on a supernatant for the testing of serum. All the mice injected intraperitoneally with botulism toxin containing supernatant died within the 96 hour test period. Those mice receiving a mixture of the trypsinized tissue extract containing the monovalent antitoxin corresponding to the type of toxin present in the tissue survived the 96 hour test period.