Pulmonary alveolar microlithiasis in an alpaca (Vicugna pacos)

Pulmonary alveolar microlithiasis (PAM) is a rare, familial disease of unknown aetiology characterised by intra-alveolar formation and accumulation of microliths. Multiple formalin-fixed tissues were submitted from a 5-month-old female alpaca that died suddenly without significant clinical signs. No gross abnormalities were observed on postmortem examination. Histological findings included PAM and severe centrilobular hepatic necrosis. Although the hepatic lesion was the likely cause of death, PAM was an incidental finding that has not been reported previously in alpacas. An overview of PAM, including pathogenesis and histopathological characteristics, are discussed in relation to the concurrent hepatic disease in the present case.

Coronavirus infection in intensively managed cattle with respiratory disease

Background

A detailed laboratory investigation identified bovine coronavirus (BCoV) as the aetiological agent in an outbreak of respiratory disease at a semi‐intensive beef cattle feedlot in south‐east Australia. The outbreak caused 30% morbidity in the resident population and also affected two cohorts of cattle that were newly introduced to the property.

Methods

At slaughter, pulmonary consolidation and inflammatory lesions in the trachea were identified in 15 of 49 animals. Pasteurella multocida or Histophilus somni was cultured from 3 of 7 animals with lesions. Histopathological examination revealed multifocal non‐suppurative bronchointerstitial pneumonia with formation of epithelial syncytial cells, sometimes associated with suppurative bronchopneumonia.

Results

BCoV was detected in nasal swabs and pulmonary lesions using real‐time reverse transcriptase–polymerase chain reaction (qRT‐PCR) assay and virus isolation. There was serological evidence of previous exposure to bovine viral diarrhoea virus, bovine respiratory syncytial virus and bovine parainfluenza virus type 3, but not to bovine herpesvirus type 1. None of these viral pathogens or Mycoplasma bovis was identified by qRT‐PCR.

Conclusion

This is believed to be the first report of BCoV in association with bovine respiratory disease complex in Australia.