Prenatal predatory stress in a wild species of subterranean rodent: Do ecological stressors always have a negative effect on the offspring?

Abstract

In pregnant females, a failed predatory event not only induces individual responses but also represents a significant change in the developmental environment of the offspring, which may lead to modifications in their phenotype that may persist at different stages of life. We evaluate whether prenatal exposure to predatory cues affects anxiety behavior, behavioral response to predator cues, stress response to immobilization, and immune response to sheep red blood cells (SRBC) and phytohemagglutinin (PHA) in juveniles of the subterranean rodent Ctenomys talarum. We found that prenatal predator stress (PPS) (1) increased juvenile anxiety-like behaviors and the appearance of antipredator behaviors, (2) did not affect the response of offspring to predatory stressors, and (3) did not influence the physiological response of juveniles to stressors (immobilization) nor the immunological responses to SRBC and PHA challenges. This work shows the influence of PPS on the development of behavioral responses in the offspring, whom displayed a state of anxiety and behavioral changes associated with decreased locomotor activity and avoidance behaviors. Thus, these individuals prenatally exposed to predatory cues show behavioral adaptations that may contribute to avoid predators in the adult life.

Effects of maternal stress induced by predator cues on spatial learning and memory of offspring in the subterranean rodent Ctenomys talarum

“…Previous studies in C. talarum showed that prenatal exposure to predator cues did not affect cortisol values in offspring, although behavioral variations were observed in the progeny of stressed mothers (Brachetta et al 2018). However, the physiological results of the present study seem to be concomitant with the assessment of cognitive parameters, suggesting both for the absence of an effect of maternal stress (during pregnancy and/or lactation) on the physiological condition of individuals.…”

“…Previous studies in C. talarum showed that prenatal exposure to predator stress modi ed juvenile responses in two behavioral tests. In the open eld, juveniles of stressed mothers decreased the time moving and the distance traveled (Brachetta et al 2018), whereas in the elevated maze, individuals spent less time in the transparent arms (Brachetta et al 2018). Both results denote a general anxiety state of individuals whose mothers were stressed during pregnancy, characterized by reduced exploratory activity and avoidance of open spaces.…”

“…In a recent study, the relationship between behavioral and physiological responses to stress was observed, nding that predator cues act as stressors that trigger a differential increase in plasma cortisol and anxious behaviors (Brachetta et al 2018). Recently, these non-lethal predatory effects were found to extend to the next generation, with variations in the behavior of juveniles from mothers exposed to predator cues during pregnancy (Brachetta et al 2018). Therefore, and considering the vital importance of the spatial abilities for the particular way of life of subterranean rodent species, and to the variety of effects that the exposure to predatory cues generate in this species, we will study how predatory stress during pregnancy and/or lactation may affect the development of spatial cognitive abilities of C. talarum progeny.…”

“…Likewise, exposure to predator odor generates a state of anxiety and induces behavioral changes associated with reduced activity and the appearance of defensive behaviors (Brachetta et al 2015). In a recent study, the relationship between behavioral and physiological responses to stress was observed, nding that predator cues act as stressors that trigger a differential increase in plasma cortisol and anxious behaviors (Brachetta et al 2018). Recently, these non-lethal predatory effects were found to extend to the next generation, with variations in the behavior of juveniles from mothers exposed to predator cues during pregnancy (Brachetta et al 2018).…”

Parents know best: transgenerational predator recognition through parental effects

“…Predator presence can also impact offspring through parental effects. Experimentally exposing breeding pairs to predators can lead offspring to adopt risk averse behaviours (Storm & Lima, 2010;McGhee et al, 2012;Brachetta et al, 2018) as well as influencing their growth and development (Agrawal, Laforsch & Tollrian, 1999;Shine & Downes, 1999;Coslovsky & Richner, 2011a) in a range of taxa. Several potential pathways through which this transfer of information may occur have been suggested.…”