LAUSR

Previous study by our group showed that acute lipopolysaccharide (LPS) switches the selection of maternal behavior to predatory behavior in rats. We studied now the effects of a challenged dose of LPS on behavioral selection of F1 lactating rats prenatally exposed to LPS. Female rats prenatally exposed to LPS (on gestation day 9.5) received a LPS challenge on the lactation day 5–6. Maternal behavior, predatory behavior to roaches and maternal general activity were studied. We also evaluated plasmatic TNF-alpha levels. Prenatal LPS (1) did not affect any of the maternal behavior parameters; (2) slightly increased predatory behavior, i.e., it increased foraging; (3) did not affect any of the general activity parameters; (4) did not affect TNF-alpha levels. Prenatal + postnatal LPS (1) impaired maternal behavior, i.e., reduced pup contact, pup grouping, and pup grooming; (2) increased predatory behavior, i.e., it increased insect contact and foraging; (3) impaired general activity, i.e., it decreased exploratory behavior and increased immobility; (4) increased TNF-alpha levels. Thus, prenatal + postnatal LPS induced sickness behavior because it decreased general activity and increased TNF-alpha levels. Independently of sickness behavior, prenatal LPS increased the switch selection of maternal behavior to predatory behavior in rats.