Bronchopneumonia by Granulicatella balaenopterae in a humpback whale (Megaptera novaeangliae)

We report a microbiological and pathological investigation of a juvenile male humpback whale (Megaptera novaeangliae) stranded in Mostardas, Rio Grande do Sul, Brazil. Macroscopically, the lung parenchyma exhibited a diffuse hyperemia, that on histological examination was composed of suppurative bronchopneumonia associated with necrosis of the bronchial epithelium. Microbiological analyses of the lung tissue demonstrated pure and significant growth of Granulicatella balaenopterae. Lastly, on the microscopic exam, the whale presented a pattern of meningoencephalitis and bacterial enterocolitis lesions, however, the etiology was not able to be accurately determined. G. balaenoptera is a bacterium that has already been detected in marine mammals; however, before this report, it had never been associated with a lesion. It is suggested that the humpback whale has been stranded due to combined disease factors such as pneumonia and meningoencephalitis.