Maternal predatory stress during pregnancy and lactation in the wild subterranean caviomorph Ctenomys talarum: effects on maternal behavior but not on anxiety behavior in the progeny
摘要
In nature, predation is one of the most ecologically relevant maternal stressors that can influence mammalian offspring during both the gestational period (by increasing plasma levels of glucocorticoids in the mother) and postpartum period (through maternally-derived glucocorticoids in milk and altering the quality and quantity of parental care). In this work, we investigated the effects of pre and/or postnatal maternal predatory stress on mother-pups interaction and offspring’s behavior in the wild subterranean rodent Ctenomys talarum. To achieve this, we evaluated the maternal care provided to the offspring, the maternal physiological condition at weaning and the behavioral profile of the progeny at the beginning of the juvenile stage. The results showed an effect of exposure to predatory cues (urine and fur odors, and immobilization) at the time of pregnancy and/or lactation on the number of negative interactions of mothers towards their pups (specifically avoidance and aggression). However, no effect of predatory stress on maternal physiological condition at weaning (plasma cortisol levels, neutrophil/lymphocyte ratio, and blood glucose levels) was observed. Furthermore, prenatal and/or postnatal exposure of mothers to predatory stress did not affect the behavioral response of juveniles in the open field test at 61 days of age. Altogether, these results show support for a low impact of maternal predatory stress on both mother and offspring in this wild rodent. Available information on the effects of maternal stress in wild species is very limited, therefore expanding and deepening studies on non-model rodents, like C. talarum, represent an important contribution to our understanding of the ecological effects of stress during gestation, maternal care, and consequently, its transgenerational effects in nature.