title: The effect of post-weaning individual housing on 50-kHz calls emitted from male rats to sexually receptive female rats.
abstract: Post-weaning individual housing induces significant alterations in the social behaviors of laboratory rats. Adult rats use ultrasonic vocalizations as a primary method to communicate social affective states. In this study, we examined the effect of prolonged post-weaning individual housing on the emission of male ultrasonic vocalizations referred to as "50-kHz calls", which are positively correlated with positive and social affective states in adult male rats. We used an anesthetized sexually receptive female rat to induce 50-kHz calls in adult males. Male subjects that were housed individually emitted fewer 50-kHz calls (both frequency modulated and flat 50-kHz calls) in adulthood compared to subjects housed socially after weaning. Our results showed that prolonged post-weaning individual housing of male rats reduced the male's ability to recognize social and reward cues from female rats and/or to emit sufficient and appropriate 50-kHz calls to female rats. These effects may be associated with developmental dysfunction induced by prolonged post-weaning individual housing.
authors.affiliation: Laboratory of Veterinary Ethology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Tokyo 113-8657, Japan. ahin@mail.ecc.u-tokyo.ac.jp
authors.forename: Hideaki
authors.initials: H
authors.lastname: Inagaki
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kuwahara
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Tsubone
authors.forename: Yuji
authors.initials: Y
authors.lastname: Mori
mesh_terms: D000819:Animal Communication; D000818:Animals; D003463:Cues; D003627:Data Interpretation, Statistical; D005260:Female; D006799:Housing, Animal; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012201:Reward; D012726:Sexual Behavior, Animal; D012931:Social Environment; D014828:Vocalization, Animal