Differences in fatty acids composition between Plasmodium infected and uninfected house sparrows along an urbanization gradient Jiménez Peñuela, Jéssica Martínez de la Puente, Josué Avian malaria Immune responses Passer domesticus PUFA Omega-3 Omega-6 This study was funded by project P11-RNM-7038 from the Junta de Andalucia and projects PGC2018-095704-B-I00 and PID2020-118205GB-I00 from the Spanish Ministry of Science and Innovation and European (FEDER) funds. CI was funded by the Swedish Research Council for Sustainable Development, FORMAS, no. 2015-00526. JJP was funded by the Fundacion Tatiana Perez Guzman el Bueno, MF is supported by the European Union'sHorizon 2020 research and innovation programme under the Marie Sklodowska-Curie (grant agreement No 844285, 'EpiEcoMod'). Alberto Pastoriza, Manuel Vazquez, Manuel Lobon, Isabel Martin, Laura Gomez, Johan Kjellberg-Jensen and Hong-Lei Wang helped with the field and laboratory work. We are grateful to all the landowners and to Consejeria de Medio Ambiente for allowing us to work on their properties. Anthropogenic activities such as intensification of agriculture, animal husbandry and expansion of cities can negatively impact wildlife through its influence on the availability of high-quality food resources and pathogen transmission. The house sparrow (Passer domesticus), an urban exploiter, is undergoing a population decline. Nutritional constrains and infectious diseases has been highlighted as potential causes. Fatty acids (FAs) play an important role in modulating certain immune responses needed to combat parasite infections. FAs are highly influenced by dietary availability and have been shown to vary between urban and rural birds. Habitat anthropization also affects avianmalaria epidemiology but little attention has been given to the relationship between blood parasite infection, host FAs composition and anthropization. Here, we analysed 165 juvenile birds either infected by Plasmodium or uninfected, captured at 15 localities grouped in triplets containing urban, rural and natural habitats. The total level of FAs was higher in birds fromurban than from rural habitats, suggesting a greater availability of fat-rich foods sources. Furthermore, Plasmodium infected birds had higher relative levels of ω-3 polyunsaturated fatty acids (PUFAs) but lower of ω-6 PUFAs than uninfected birds. In concordance, the ω-6/ω-3 ratiowas also lower in infected than in uninfected birds, but only from natural habitats, likely driven by the slightly higher ω-3 PUFAs in infected birds from natural habitats. Birds from anthropized environments may metabolize the ω-3 PUFAs to promote anti-inflammatory responses against stressors, which would result in lower ω-3 affecting their response against Plasmodium. Alternatively, lower ω-6 PUFAs may influence birds susceptibility to infection due to a weaker pro-inflammatory response. These descriptive results do not allow us to identify the causality of these associations but highlight the need to further investigate the relevance of FAs for birds to fight infectious diseases in habitats with different degree of urbanization. 2022-06-10T08:26:09Z 2022-06-10T08:26:09Z 2022-01-05 journal article Jéssica Jiménez-Peñuela... [et al.]. Differences in fatty acids composition between Plasmodium infected and uninfected house sparrows along an urbanization gradient, Science of The Total Environment, Volume 815, 2022, 152664, ISSN 0048-9697, [https://doi.org/10.1016/j.scitotenv.2021.152664] http://hdl.handle.net/10481/75413 10.1016/j.scitotenv.2021.152664 eng info:eu-repo/grantAgreement/EC/H2020/844285 http://creativecommons.org/licenses/by-nc-nd/3.0/es/ open access Atribución-NoComercial-SinDerivadas 3.0 España Elsevier