'Disease-smart outcrossing can enhance individual fitness and increase survival via immune priming against pathogens: new approaches to strengthen genetic rescue efforts

We studied the potential of combining insect immune priming with the
introduction of diverse migrants to safeguard individuals from an inbred
population from disease as a technique for enhancing genetic rescue
efforts. Immune priming in insects refers to the stronger immune response
insects have against pathogens following exposure. This enhanced immunity
can be passed on to offspring and holds promise for insect conservation
efforts against diseases. We compared the fitness benefits of individuals
from a small, inbred population with two treatments: the addition of
genetically diverse migrants that had not been primed and the addition of
immune-primed migrants. While both types of migrants enhanced
reproduction, as in cases of genetic rescue, only primed migrants led to
improved survival on exposure to a pathogen. Better immunity led to a
trade-off with reproduction in immune-primed migrants, but this was not
evident upon outcrossing with the target individuals, revealing synergies
between hybrid vigor and immune priming. Given the demographic constraints
and stochasticity that can exacerbate the effects of disease outbreaks in
small populations, our results serve as a proof of concept for combining
immune priming with assisted migration to offer a proactive strategy to
mitigate disease impacts while enhancing genetic diversity.