The transfer of antibodies from mother to offspring provides crucial protection against infection to offspring during early life. However, few studies have tested the consequences of variation in maternal antibody transfer for offspring fitness in the wild. Further, separating out the immunoprotective effects of antibodies from their association with nutritional resources provided by the mother is difficult. Here, we measured plasma levels of total and parasite-specific antibody levels in neonatal (<10 days old) wild Soay sheep over 25 years to quantify variation in maternal antibody transfer and test its association with offspring survival. Maternal antibody transfer was predicted by maternal age and previous antibody responses, and was consistent within mothers across years. Neonatal total IgG antibody levels were positively related to early growth, suggesting they reflected nutritional transfer. Neonatal parasite-specific IgG levels positively predicted first year offspring survival, independent of lamb weight, total IgG levels and subsequent lamb parasite-specific antibody levels. This relationship was in part mediated via an indirect negative association with parasite burden. We show that among-female variation in maternal transfer of immunity can have long-term effects on offspring growth, parasite burden and fitness in the wild, and is likely to impact naturally-occurring host and parasite dynamics.

This data was collected as part of the long term individual based study on the Soay sheep of St Kilda in Scotland.

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SOAY SHEEP PROJECT DATA REUSE:

The attached file contains data derived from the long term field project
monitoring individual Soay sheep on St Kilda and their environment.  This is a
request to please let us know if you use them.  Several people have spent the
best part of their careers collecting the data.  If you plan to analyse the
data, there are a number of reasons why it would be very helpful if you could
contact Josephine Pemberton (j.pemberton@ed.ac.uk) before doing so.

[NB. If you are interested in analysing the detailed project data in any depth 
you may find it helpful to have our full relational database rather than the
file(s) available here.  If so, then we have a simple process for bringing you
onto the project as a collaborator.]

1) The data can be subject to change due to updates in the pedigree, merging of
records, occasional errors and so on.

2) The data are complex and workers who do not know the study system may
benefit from advice when interpreting it.

3) At any one time a number of people within the existing project collaboration
are analysing data from this project. Someone else may already be conducting
the analysis you have in mind and it is desirable to prevent duplication of
effort.

4) In order to maintain funding for the project(s), every few years we have to
write proposals for original analyses to funding agencies. It is therefore very
helpful for those running the project to know what data analyses are in
progress.

5) Sheep identifiers may vary relative to other data archives from papers using
the Soay sheep data.

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DATA DESCRIPTION:

These data are related to the manuscript:

Maternally-derived anti-helminth antibodies predict offspring survival in a wild mammal

A. M. Sparks, A. D. Hayward, K. Watt, J. G. Pilkington, J. M. Pemberton, S. E. Johnston, T. N. McNeilly, D. H. Nussey

Please see the README file for descriptions of the columns in the dataset.

For questions related specifically to this dataset, please contact Alexandra Sparks (A.M.Sparks@leeds.ac.uk) or Dan Nussey (dan.nussey@ed.ac.uk)