Foetal and postnatal exposure to high temperatures alter growth pattern but do not modify reproductive function in male rabbits.

Purpose: The 'foetal origin hypothesis' postulates that a number of organ structures and associated functions undergo programming during embryonic and foetal life and the neonatal period, which determines the set point of physiological and metabolic responses that carry into adulthood. We evaluate the relationship between high environmental temperatures and the reproductive function of male offspring to determine whether pregnant mammals and their infants are potentially vulnerable to the effects of climate change.
Methods: Rabbit pups were exposed to high temperatures during gestation and lactation.
Results: Foetal and postnatal exposure to high temperatures did not alter semen characteristics and was associated with a similar fertility rate and number of pups born. Moreover, males showed reduced rate of maturing and carcass traits at adulthood.
Conclusion: Our findings suggest that male exposure during the foetal period to high temperatures did not affect sperm quality but permitted an adaptive phenotypic plasticity of growth in adulthood.