Specificity of California mouse pup vocalizations in response to olfactory stimuli

Abstract

To investigate flexibility in vocal signaling by rodent pups, we examined whether olfactory stimuli influence characteristics of pup calls and how these calls may be affected by sex and litter size in California mice (Peromyscus californicus). Pups were isolated and recorded during a 3-min baseline period followed by a 5-min exposure to bedding containing scent from their home cage, scent from the home cage of an unfamiliar family, coyote urine, or no scent (control). Latency to call, call rate, and call characteristics (duration, frequency, and amplitude) were compared between the baseline and scentexposure periods and among olfactory conditions. Compared with the control condition, pups from two-pup litters called more quietly when exposed to odor from a predator, whereas pups from three-pup litters called more loudly. Additionally, pups showed nonsignificant tendencies to reduce call rates in response to odors from their home cage and to increase call rates when exposed to predator urine. Last, males produced higher-frequency calls and more ultrasonic vocalizations than females. These results indicate that pup calling behavior in this species can be influenced by acute olfactory stimuli as well as litter size and sex. The flexibility of pup calling in response to these three variables potentially increases the communication value of pup calls and helps shape the parents' responses.

Effects of Parenthood on Neural Responses to Pup-Related Cues

“…This study investigated the neural pathways that are activated in response to pup-related sensory stimuli -pup scents and vocalizations -in male and female California mice, as well as the effects of parenthood on these neural responses. Neural pathways involved in olfactory and auditory processing interact with pathways involved in the onset of parental care, suggesting that olfaction and audition may be important sensory modalities for parental care, at least in rodents (Kuroda et al, 2011;Horrell et al, 2019;Wilson et al, 2022). The main olfactory bulbs (MOB) are essential for the detection of chemosensory stimuli and may have downstream effects on parental behavior by sending information to other brain regions.…”