First molecular detection of Bartonella spp. in seabirds (Procellariiformes and Sphenisciformes) rescued on the Brazilian coast.

The present study aimed to investigate the occurrence and molecular identity of Bartonella spp. in Procellariiformes and Magellanic penguins (Spheniscus magellanicus) rescued along the southern and southeastern coasts of Brazil. A total of 52 blood samples from twelve Procellariiformes species and 170 blood samples and 30 spleen samples from Magellanic penguins were collected along the coasts of Santa Catarina and São Paulo states. Following DNA extraction, all samples were screened by conventional PCR targeting the avian β-actin endogenous gene. Successfully amplified samples were further tested by qPCR targeting the 16S-23S ribosomal DNA internal transcribed spacer (ITS) region for Bartonella detection. Positive samples were subjected to additional conventional PCR assays targeting the gltA, ftsZ, groEL, nuoG, pap31, rpoB, ribC, and 16S-23S (ITS) genic regions for molecular characterization. Overall, 56 samples (22.2 %; 56/252) tested positive in the screening, including five blood samples from Procellariiformes (Thalassarche melanophris, n=3; Thalassarche chlororhynchos, n=2) and 51 biological samples (91.1 %; 51/56) from S. magellanicus (42 spleen, 9 blood). Molecular characterization was successful only for S. magellanicus, with amplification of nuoG (14.2 %; 8/56; four spleens, four blood samples), rpoB (12.5 %; 7/56; four spleens, three blood samples), and ITS (12.5 %; 7/56; four spleens, three blood samples). The obtained sequences were closely related to Bartonella henselae previously detected in humans, cats, mongooses, and ticks associated with Passeriformes. In conclusion, Bartonella genotypes circulate in Procellariiformes, and genotypes closely related to B. henselae are present in Magellanic penguins that arrive in the Brazilian coast.