Data from: Stable isotope tracers reveal a trade-off between reproduction and immunity in a reptile with competing needs

1.Trade-offs between the reproductive and immune systems are predicted
when resources are limited, but are difficult to measure. 2.We used 15N
labeled amino acids to directly compare protein allocation by lizards to
eggs and healing wounds. 3.We showed that these two demands compete for
the same resource, and that the ratio of protein allocation between them
was related to body size, reproductive stage, and plasma corticosterone
levels. 4.On average, rates of leucine deposition into eggs (0.022 μg/day)
were an order of magnitude greater than those into scabs (0.002 μg/day),
similar to leucine excretion rates (0.027 μg/day), and about half as large
as leucine egestion rates (0.054 μg/day). 5.We found that earlier
reproductive stages and greater amounts of stored energy, but not
manipulated food availability or the amount of food consumed, increased
the absolute and relative allocation of protein to self-maintenance. 6.We
provide direct evidence for amino acid trade-offs between reproduction and
wound healing.