Postpartum maternal exposure to predator odor alters offspring antipredator behavior, basal HPA axis activity and immunoglobulin levels in adult Brandt's voles.

Predation risk can program offspring behavior, physiology, and fitness through maternal effect, but most studies have mainly focused on this effect during pregnancy; little is known about the effect of postpartum predation risk on offspring's phenotype. Here, we compared the antipredator behaviors of adult offspring (approximately 90 days old) produced by female Brandt's voles (Lasiopodomys brandtii) exposed to one of three treatments: cat odor (CO), rabbit odor (RO), and distilled water (DW) for 60 min daily from postpartum day 1-18. Basal levels of plasma adrenocorticotropic hormone (ACTH) and corticosterone (CORT), hypothalamic corticotrophin releasing hormone (CRH), as well as spleen immunoglobulins (IgA, IgM, and IgG) were also measured. Our data showed that the offspring of CO-exposed mothers displayed less head-out behavior to acute 15-min CO exposure, and female offspring showed more freezing behavior. CO offspring showed significantly lower basal ACTH and CORT levels than the RO and DW offspring. Additionally, female but not male CO offspring had higher hypothalamic CRH expression and spleen IgG levels than controls, showing a sex-specific effect. These findings demonstrate that postpartum maternal predator risk exposure promotes a passive-avoidant response to these cues in adult offspring, showing a cross-generational maternal effect of postpartum predation risk. Further, these changes may be associated with alterations in the hypothalamic-pituitary-adrenal axis and immune function.

Repeated predator odor exposure alters maternal behavior of postpartum Brandt's voles and offspring's locomotor activity.

Recent evidence indicates that predation risk plays a special role in the rodent behavior of dams and offspring, but little is known about the effect of maternal exposure to the predator cues in the absence of pups. Here, we assessed the effects of repeated predator odor exposure on various maternal responses in postpartum Brandt's voles (Lasiopodomys brandtii). We also examined offspring's behavioral response to a novel environment. Only mother voles were exposed to distilled water, rabbit urine and cat urine for 60 min daily from postpartum day (PP) 1-18. Maternal behavior was immediately tested after these exposures on PP1, 3, 6, 9 and 18. Repeated cat odor (CO) and rabbit odor (RO) exposure disrupted hovering over pups in a time-dependent fashion. Repeated CO exposure also time-dependently disrupted pup retrieval, whereas RO exposure induced long-term reduction in pup licking. Juvenile offspring of CO-exposed mothers showed increased locomotor activity and decreased rearing in the open field at postnatal day 30. These findings demonstrated that maternal exposure to predator or non-predator odors had a disruptive effect on the maternal behavior of Brandt's voles when only the mother was exposed to these odors, and that the adversity experience with predation risk significantly impacted the behavioral development of offspring. Future work should explore possible behavioral mechanisms, such as the effect of predation risk, on the dams' emotional processing or pup preference.

Fabric Moisture Uniform Control to Study the Influence of Air Impingement Parameters on Fabric Drying Characteristics.

Impinging dryness is now a widely used and effective way for fabric drying due to its high heat and mass transfer coefficient. Previous studies on fabric drying have neglected the contributions of moisture uniformity and diffusion coefficient to the drying process; though, they have recently been shown to have a significant influence on drying characteristics. This report outlines a step-by-step procedure to investigate the effects of air impingement parameters on a fabric's drying characteristics by controlling the uniformity of its area moisture distribution. A hot air blower unit equipped with an angle adjustable nozzle is used to generate air flow with different velocities and temperatures while the drying process is recorded and analyzed using an infrared thermograph. In addition, a uniform padder is adapted to ensure the fabric's moisture uniformity. Impinging drying is studied under different initial conditions by changing the air flow temperature, velocity, and direction, then the applicability and suitability of the protocol are evaluated.