title: Factors affecting the levels of protection transferred from mother to offspring following immune challenge.
abstract: BACKGROUND
  The transfer of antibodies from mother to offspring is key to protecting young animals from disease and can have a major impact on responses to infection and offspring fitness. Such maternal effects also allow young that may be exposed to disease in early life to focus resources on growth and development at this critical period of development. Maternally transferred antibodies are therefore an important source of phenotypic variation in host phenotype as well as influencing host susceptibility and tolerance to infection across generations. It has previously been assumed the transfer of antibodies is passive and invariant and reflects the level of circulating antibody in the mother at the time of transfer. However, whether females may vary in the relative amount of protection transferred to offspring has seldom been explored.
  
  
  RESULTS
  Here we show that females differ widely in the relative amount of specific blood antibodies they transfer to the embryonic environment (range 9.2%-38.4% of their own circulating levels) in Chinese painted quail (Coturnix chinensis). Relative transfer levels were unrelated to the size of a female's own immune response. Furthermore, individual females were consistent in their transfer level, both across different stages of their immune response and when challenged with different vaccine types. The amount of antibody transferred was related to female condition, but baseline antibody responses of mothers were not. However, we found no evidence for any trade-offs between the relative amount of antibody transferred with other measures of reproductive investment.
  
  
  CONCLUSIONS
  These results suggest that the relative amount of antibodies transferred to offspring can vary significantly and consistently between females. Levels of transfer may therefore be a separate trait open to manipulation or selection with potential consequences for offspring health and fitness in both wild and domesticated populations.
authors: Centre for Infection, Immunity and Evolution, Institute of Evolutionary Biology, School of Biology, King's Buildings, University of Edinburgh, Edinburgh EH9 3JT, UK.
authors: Christina M
authors: CM
authors: Coakley
authors: Centre for Infection, Immunity and Evolution, Institute of Evolutionary Biology, School of Biology, King's Buildings, University of Edinburgh, Edinburgh EH9 3JT, UK.
authors: Vincent
authors: V
authors: Staszewski
authors: Centre for Infection, Immunity and Evolution, Institute of Evolutionary Biology, School of Biology, King's Buildings, University of Edinburgh, Edinburgh EH9 3JT, UK.
authors: Katherine A
authors: KA
authors: Herborn
authors: Centre for Infection, Immunity and Evolution, Institute of Evolutionary Biology, School of Biology, King's Buildings, University of Edinburgh, Edinburgh EH9 3JT, UK.
authors: Emma Ja
authors: EJ
authors: Cunningham
keywords: Differential allocation; Ecoimmunology; Immunity; Maternal antibodies; Maternal effect; Trade-offs