Identification of Haemoproteus infection in an imported grey crowned crane (Balearica regulorum) in China

Blood parasites from the order Haemosporida infect many vertebrates and cause malaria-like diseases. In this study, a haemosporidian infection was detected in a sick grey crowned crane imported into China using a combination of morphological and molecular approaches. Blood samples were collected from the jugular vein and processed for morphological identification of infective parasites using stained blood smears and microscopy. No merogony occurs in the blood cells, and sporadic pigment granules were observed. Nested-PCR assays were employed for a molecular examination, which indicated that the cytb gene of this parasite had 94.1-94.9% identity to Haemoproteus antigonis. Subsequently, its mitochondrial genome structure was determined by high-throughput sequencing using the DNBSEQ-T7 platform. The determined structure was confirmed by the Sanger sequencing using amplicons. The mitochondrial genome obtained for this parasite exhibited a low CG content (32.0%) and possessed three protein-coding genes, encoding 1068 amino acids, which constituted 53.7% of the genome. Phylogenetic analysis indicated that this parasite clustered with Haemoproteus sp. is detected in grey crowned cranes from Africa. This parasite was likely acquired during importation of this animal; thus, strict quarantine of imported ornamental animals is required to prevent the entry of new pathogens.