Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico City, 04510, Mexico.
Facultad de Estudios Superiores Zaragoza, Mexico City, 09230, Mexico.
Sci Rep. 2022 Apr 27;12(1):6892. doi: 10.1038/s41598-022-11075-1.
Haemosporidian parasites are common in birds but are seldom reported in seabirds. The absence of vectors or genetic resistance to infection have been proposed to explain this pattern. However, screening of blood parasites in many seabirds has been done only by visual inspection of blood smears, which can miss low-intensity infections, and molecular detection of blood parasites must be supported by detection in blood smears to confirm the presence of haemosporidians and avoid false positive cases. Here, we tested for the presence of blood parasites of the genera Plasmodium, Haemoproteus and Leucocytozoon, combining inspection of blood smears and PCR-based detection methods in a highly philopatric colony of blue-footed boobies (Sula nebouxii) in the Tropical North Pacific. Our results indicate that adults in this colony are likely free of these blood parasites, probably due to unsuitable conditions for insect vectors in booby breeding sites, although potential genetic resistance of blue-footed boobies to infection deserves examination. Apparent absence of blood parasites in Isla Isabel boobies indirectly adds to the growing evidence of variation in parasite infections among avian host species that coexist locally.
血孢子虫寄生虫在鸟类中很常见，但在海鸟中很少报道。缺乏媒介或对感染的遗传抗性被认为可以解释这种模式。然而，许多海鸟的血液寄生虫筛查仅通过血液涂片的目视检查进行，这可能会错过低强度感染，并且必须通过血液涂片检测来支持血液寄生虫的分子检测，以确认存在血孢子虫并避免假阳性病例。在这里，我们结合血液涂片检查和基于 PCR 的检测方法，在热带北太平洋的一个高度恋巢的蓝脚鲣鸟（Sula nebouxii）群体中检测了疟原虫、疟原虫和白细胞虫属的血液寄生虫。我们的结果表明，该群体中的成年个体可能没有这些血液寄生虫，这可能是由于鲣鸟繁殖地的昆虫媒介条件不合适，尽管蓝脚鲣鸟对感染的潜在遗传抗性值得研究。伊莎贝尔岛鲣鸟中明显没有血液寄生虫，这间接增加了越来越多的证据表明，在当地共存的鸟类宿主物种中，寄生虫感染存在差异。
