Rapid identification of Mycoplasma bovis infections in cattle is a key factor to guide antimicrobial therapy and biosecurity measures. Recently, nanopore sequencing became an affordable diagnostic tool for both clinically relevant viruses and bacteria, but the diagnostic accuracy for M. bovis identification is undocumented. Therefore, in this study nanopore sequencing was compared to rapid identification of M. bovis with MALDI-TOF MS (RIMM), and triplex real-time PCR in a Bayesian latent class model (BLCM) for M. bovis in bronchoalveolar lavage fluid (BALf) obtained from calves. In practice, pooling of samples is often used to save money, but the influence on diagnostic accuracy has not been described for M. bovis . Therefore, a convenience sample of 17 pooled samples containing 5 individual BALf samples per farm was analyzed as well. The results of the pooled samples were compared to the individual samples, to determine sensitivity (Se) and specificity (Sp). The BLCM showed a good Se (77.3%; 95% Credible Interval: 57.8%-92.8%) and high Sp (97.4%; 91.5%-99.7%) for nanopore sequencing compared to RIMM (Se: 93.0%; 76.8%-99.5%, Sp: 91.3; 82.5%-97.0%) and real-time PCR (Se: 94.6%; 89.7%-97.7%, Sp: 86.0%; 76.1-93.6%). Se and Sp of pooled analysis for M. bovis were 85.7% (95% confidence interval: 59.8-111.6%) and 90.0% (71.4-108.6%%) for nanopore sequencing and 100% (100%-100%) and 88.9% (68.4-109.4%) for RIMM, respectively. In conclusion, nanopore sequencing is a rapid, reliable tool for the identification of M. bovis . To reduce costs and increase the chance of M. bovis identification, pooling of 5 samples for nanopore sequencing and RIMM is possible.

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This case report describes the anaesthesia of a ram undergoing an exploratory laparotomy, which suffered from respiratory distress during the perioperative period. On the morning of surgery, the animal presented with oedematous ears, most likely caused by a tight-fitting muzzle that had been used for preoperative fasting. After sedation, a mild stridor was heard. During endotracheal intubation, a swollen larynx was observed, and a frothy discharge emerged through the endotracheal tube after placement. Most likely, the tight muzzle caused a partial obstruction of the nostrils, increasing the respiratory effort and causing an increase in the pressure gradient, which provoked laryngeal and pulmonary oedema. Treatment consisted of repeated suctioning of fluid from the endotracheal tube, furosemide, dexamethasone, mechanical ventilation with 100% oxygen during anaesthesia and oxygen supplementation during recovery. Despite moderately low arterial oxygen tension during anaesthesia, the animal recovered uneventfully and did not show further signs of respiratory distress.

Background Between 2007 and 2011 several thousands of calves died from bovine neonatal pancytopenia (BNP), a bleeding syndrome triggered by vaccine induced alloantibodies from the dams. Following withdrawal of the involved bovine viral diarrhoea virus (BVDv) vaccine, the incidence of this condition rapidly decreased, with no reported cases in the last 5 years. Here, we report a recent immune-mediated pancytopenia in three calves from two different suckler herds, clinically indistinguishable from BNP. Case presentation Three Belgian Blue suckler calves from two different farms, aged around two weeks, showed multiple bleedings disseminated on the skin and petechiae and ecchymoses on the mucosae. Blood examination confirmed anaemia, leukopenia and thrombocytopenia. BVDv infection was excluded. Despite blood transfusion and cortisone therapy, all three animals died. Necropsy and histology confirmed bone marrow depletion. Binding of IgG from the dams on leukocytes of the calves was demonstrated by flow cytometry. Two calves, originating from the same farm, received colostrum from the same dam. None of the calves were given colostrum replacers or colostrum supplements. No link with the BNP causing BVDv vaccine could be evidenced. However, dams had been vaccinated against bovine herpesvirus 1, parainfluenza-3 virus, bovine respiratory syncytial virus and bluetongue virus serotype 8. Conclusions Alloimmune mediated pancytopenia was evidenced in three animals, clinically and pathologically indistinguishable from BNP. Whether this disease is again vaccine mediated remains to be determined.