DAO 140:143-149 (2020)  -  DOI: https://doi.org/10.3354/dao03504

ABSTRACT: Cryptosporidium spp. are parasitic intracellular protozoa that infect the digestive, respiratory, and urinary tracts of vertebrates. The disease affects many different avian species across all continents, and >25 species and genotypes of Cryptosporidium have been documented infecting birds. We report on an outbreak of cryptosporidiosis in African penguin Spheniscus demersus chicks admitted to a rehabilitation center in South Africa from February 2012 to October 2013. Eighteen cases were confirmed through histopathology. The most frequent clinical signs were regurgitation (78%), dyspnea (72%), decreased weight gain or weight loss (72%), and lethargy (50%). Clinical signs began 8-46 d after hatching or admission (median: 13 d), and death followed 1-41 d after the onset of clinical signs (median: 13.5 d). The most frequent necropsy findings were stomach distended with undigested food or gas (78%), mildly reddened lungs (56%), spleen petechial hemorrhage (44%), and kidney congestion (39%). The most frequent histopathological findings were necrotic bursitis (89%), necrotic enteritis (83%), and bursal atrophy (67%). Small round or oval basophilic bodies (3-5 µm diameter) consistent with Cryptosporidium sp. were closely associated with the surface of the epithelial cells or in the lumen of the bursa (89%), large intestine (61%), small intestine (44%), trachea (22%), and ventriculus (6%). Transmission electron microscopy of 1 case confirmed that these organisms were Cryptosporidium sp. To our knowledge, this is the first report of cryptosporidiosis in penguins, raising concern of the potential implications for the conservation of these species.

KEY WORDS: Apicomplexa · Protozoal disease · Seabird · Spheniscidae · Wildlife rehabilitation