A novelSarcocystis-associated encephalitis and myositis in racing pigeons

Abstract

Sarcosporidian cysts in the skeletal muscle of domestic pigeons (Columba livia f. domestica) have previously been attributed to infection with Sarcocystis falcatula, which is shed in the faeces of the opossum (Didelphis virginiana). Here, we describe fatal spontaneous encephalitis and myositis associated with Sarcocystis infections in three flocks of racing pigeons with 47 of 244 animals affected. The clinical course was characterized by depression, mild diarrhoea, torticollis, opisthotonus, paralysis and trembling. Histopathological examination of 13 pigeons revealed generalized severe granulomatous and necrotizing meningoencephalitis and myositis with sarcosporidian cysts. Light and transmission electron microscopy identified cysts in heart and skeletal muscle of 1 to 2 mm in length and 20 to 50 mm in width. These were subdivided into small chambers by fine septae and filled with lancet-shaped cystozoites (7.5)1.5 mm) and dividing metrocytes, which is characteristic for Sarcocystis. The cysts had smooth walls and were devoid of protrusions typical of S. falcatula. Polymerase chain reaction amplification and sequencing of the internal transcribed spacer region (ITS-1) and the complete 28S rRNA identified a novel Sarcocystis species with only 51% ITS-1 nucleotide sequence similarity with S. falcatula. A phylogenetic comparison of the 28S rRNA revealed close sequence homologies with Frenkelia microti, Frenkelia glareoli and Sarcocystis neurona. The clinical, histopathological, electron microscopic and genetic data are unlike any previously described protozoan infections in pigeons, suggesting a novel, severe disease due to an as yet undescribed Sarcocystis species.

Parasite distribution and early-stage encephalitis inSarcocystis calchasiinfections in domestic pigeons (Columba liviaf.domestica)

“…In 31.8% (seven of 22) of the pigeons with encephalitis, few sarcocysts were identified in unaffected brain areas. These results are consistent with the observations made in naturally and experimentally infected pigeons during the acute and the chronic phase of PPE (Olias et al, 2009a(Olias et al, , 2013. In contrast, in some naturally infected pigeons in the USA, schizonts were identified in cerebral lesions suggesting the potential of S. calchasi schizonts to induce an inflammatory response in the brain (Olias et al, 2014).…”

“…The apicomplexan parasite Sarcocystis calchasi was recently identified as the causative agent of pigeon protozoal encephalitis (PPE), a severe neurologic disease in domestic pigeons (Columba livia f. domestica) (Olias et al, 2009a(Olias et al, , 2009b. Pigeons serve as intermediate hosts in the lifecycle of S. calchasi.…”

Muscular Sarcocystosis and Non-Specific Rheumatic Diseases are growing Neglected Coming Challenge

“…A painful mass in the right lumbar region in female patients in India was caused by muscular sarcocystosis (Lingappa et al, 2015). Moreover, fatal encephalitis and myositis associated with Sarcocystis infections in three flocks of racing pigeons were reported by (Olias et al, 2009). …”

Co-infection of sarcocystis sp. and Hadjelia truncata in fantail pigeons (Columba livia domestica)

“…An early literature report described an emerging neurologic disease with lethal outcome for domestic pigeons (Columba livia f. domestica) in Berlin, Germany, caused by a novel Sarcocystis sp. (Olias et al, 2009). Moreover, newly characterised non-pathogenic species S. columbae have been found in wood pigeons (Columba palumbus) in Germany (Olias et al, 2010b).…”

“…(Protozoan; Apicomplexa) may infect birds as intermediate hosts, but wild Columbiformes, which include pigeons, are rarely affected (Ecco et al, 2008;Olias et al, 2009). Among the few species affecting domestic poultry are S. horvathi and S. wenzeli, which infect chickens, and S. rileyi, for which ducks are intermediate hosts (Riley, 1931;Wenzel et al, 1982).…”