72.4 Friday, Jan. 6 Acute effects of corticosterone injection on paternal behavior in California mouse (Peromyscus californicus) fathers HARRIS, BN*; PEREA-RODRIGUEZ, JP; SALTZMAN, W; Univ. of California, Riverside; Univ. of California, Riverside; Univ. of California, Riverside email@example.com
In the face of stressors, both acute and chronic, a trade-off between self-maintenance and reproductive behavior (both sexual and parental) has been documented, and glucocorticoids (GCs) are thought to mediate this effect. Studies implementing long-term GC elevation support a role of these hormones in disrupting paternal behavior in response to chronic perturbations, but no study has experimentally tested the effects of acute glucocorticoid elevation on paternal behavior. We tested the hypothesis that an acute corticosterone (CORT) increase would decrease paternal behavior in fathers and would lead to longer-term effects on reproductive success, as even short-term increases in CORT have been shown to produce lasting effects on the hypothalamic-pituitary-adrenal axis. First-time fathers were injected with 30mg/kg CORT, 60 mg/kg CORT, or vehicle, or left unmanipulated; however, groups were analyzed as control (unmanipulated + vehicle, n=15) and CORT (30mg/kg + 60mg/kg, n=16) following plasma CORT determination. Approximately 1.5-2h following injection two behavioral paradigms were used to access both paternal and non-paternal behaviors. CORT treatment increased the latency to contact a pup during the second behavioral test, but this effect was no longer significant after controlling for alpha inflation. CORT treatment did not alter any other measured behavior during either testing scenario, nor did it affect any long-term parameters (male body mass or temperature, pup growth rate, pup survival, interbirth interval, number or mass of pups born in the second litter). Regardless of treatment group, however, fathers showed a significant rise in body mass at day 30 postpartum, followed by a decrease in body mass after the birth of the second litter.