Seasonal variation in sex-specific immunity in wild birds

José O. Valdebenito* (Corresponding author), Naerhulan Halimubieke, Ádám Z. Lendvai, Jordi Figuerola, Götz Eichhorn, Tamás Székely

*Corresponding author for this work

Research output: Contribution to journal/periodicalArticleScientificpeer-review

23 Citations (Scopus)
34 Downloads (Pure)


Whilst the immune system often varies seasonally and exhibits differences between males and females, the general patterns in seasonality and sex differences across taxa have remained controversial. Birds are excellent model organisms to assess these patterns, because the immune system of many species is well characterised. We conducted a meta-analysis using 41 wild bird species from 24 avian families to investigate sex differences and seasonal (breeding/non-breeding) variations in immune status, including white blood cell counts, phytohaemagglutinin (PHA) test, bacteria-killing ability (BKA), haemolysis and haemagglutination assays. We found male-biased macrophage concentration, BKA and haemolysis titers, but only during the breeding season. Sex-specific heterophil concentrations, heterophil/lymphocyte ratios and PHA responses differed between breeding and non-breeding, suggesting larger changes in males than in females. Importantly, sex differences in immune status are stronger during the breeding period than during the non-breeding period. Taken together, our study suggests that both seasonal variation and sex differences in immune system are common in birds, although their associations are more complex than previously thought.

Original languageEnglish
Article number1349
JournalScientific Reports
Publication statusPublished - 2021


  • international
  • Plan_S-Compliant_OA


Dive into the research topics of 'Seasonal variation in sex-specific immunity in wild birds'. Together they form a unique fingerprint.

Cite this