Molecular characterization of malarial parasites in captive passerine birds.
Seven of 28 passerine birds that died in captivity were positive for malarial parasites by polymerase chain reaction targeting the mitochondrial cytochrome b (cytB) and apicoplast ribosomal RNA (rRNA) genes. Each bird was infected with a single parasite lineage having a unique genotype. Apicoplast rRNA sequences were present both in Haemoproteus spp. and Plasmodium spp. and had typically high adenosine + thymidine content. Phylogenies for cytB and apicoplast rRNA sequences were largely congruent and supported previous studies that suggest that Plasmodium-Haemoproteus spp. underwent synchronous speciation with their avian hosts, interrupted by sporadic episodes of host switching. Apicoplast phylogeny further indicated that Haemoproteus spp. are ancestral to Plasmodium spp. All the 7 infected passerine birds had histologic lesions of malaria, and malarial parasites may have contributed to the death of at least 4 animals. These findings provide new genetic data on passerine hematozoa, including initial sequences of apicoplast DNA, and emphasize the relevance of parasite prevalence, evolutionary relationships, and host switching to modern management and husbandry practices of captive birds.
Schrenzel
Mark D
MD
Zoological Society of San Diego, Center for Reproduction of Endangered Species, Department of Pathology, Molecular Diagnostics Laboratory, P.O. Box 120-551, San Diego, California 92112, USA. mschrenzel@sandiegozoo.org
Maalouf
Gabriel A
GA
Keener
Laura L
LL
Gaffney
Patricia M
PM
D000818:Animals; D000836:Animals, Zoo; D001483:Base Sequence; D045303:Cytochromes b / Q000235:genetics; D016054:DNA, Protozoan / Q000032:analysis* / Q000737:chemistry; D005260:Female; D005838:Genotype; D016787:Haemosporida / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D008289:Malaria, Avian / Q000401:mortality / Q000469:parasitology*; D008297:Male; D008925:Mites / Q000469:parasitology; D008969:Molecular Sequence Data; D010802:Phylogeny; D010961:Plasmodium / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012335:RNA, Ribosomal / Q000235:genetics; D016415:Sequence Alignment / Q000662:veterinary; D020308:Songbirds / Q000469:parasitology*
D016054:DNA, Protozoan; D012335:RNA, Ribosomal; D045303:Cytochromes b