Office of Research, UC Riverside
Wendy Saltzman
Professor of Evolution, Ecology & Organismal Biology
Evolution, Ecology & Orgns Bio
saltzman@ucr.edu
(951) 827-6356


DDIG: Effects of placentophagia on anxiety and paternal behavior in male California mice (Peromyscus californicus)

AWARD NUMBER
006835-002
FUND NUMBER
21267
STATUS
Closed
AWARD TYPE
3-Grant
AWARD EXECUTION DATE
6/15/2014
BEGIN DATE
7/1/2014
END DATE
6/30/2015
AWARD AMOUNT
$19,754

Sponsor Information

SPONSOR AWARD NUMBER
IOS-1407370
SPONSOR
NATIONAL SCIENCE FOUNDATION
SPONSOR TYPE
Federal
FUNCTION
Organized Research
PROGRAM NAME

Proposal Information

PROPOSAL NUMBER
14050408
PROPOSAL TYPE
New
ACTIVITY TYPE
Basic Research

PI Information

PI
Saltzman, Wendy
PI TITLE
Other
PI DEPTARTMENT
Evolution, Ecology & Orgns Bio
PI COLLEGE/SCHOOL
College of Nat & Agr Sciences
CO PIs

Project Information

ABSTRACT

Paternal care is rare in mammals, but can have a critical influence on offspring survival and development in the species in which it occurs, including humans. Although neuroendocrine and experiential influences on paternal behavior have been studied in numerous species, the proximate regulation of the onset of paternal care remains poorly understood. In female mammals, hormonal changes associated with the onset of motherhood (i.e., with pregnancy, parturition and lactation) activate maternal behavior in part by decreasing new mothers' anxiety-like or neophobic responses towards their newborns. It is unknown whether anxiety reduction plays a similar role in the onset of male parental care, but several physiological and behavioral measures of anxiety have been negatively correlated with aspects of paternal care. The aim of this research is to study the role of reduction in anxiety "permitting" the expression of paternal behavior by males. This research has great relevance to human and human behavior and inadequate paternal involvement and care is associated with many difficulties observed in family interactions and subsequent behavior of children as parents. To test this researcher will study the California mice, which displays many of the same social behavior and family structures as humans.

Ingestion of placenta by parturient female mammals is very common, and can elicit behavioral and physiological changes in mothers that enhance their care of offspring. In several biparental mammals, fathers also ingest placenta during the birth of their young; however, the function of placentophagia by males is unknown. Recent research conducted by the co-PI and PI has found that when sexually inexperienced male California mice (Peromyscus californicus) are administered placenta via oral gavage, they subsequently show reduced latencies to approach a novel object or an unrelated pup, as well as reduced neural activity (Fos-immunoreactivity) in the dorsal bed nucleus of the stria terminalis, a brain region associated with anxiety. Thus, these behavioral and neural results suggest that placenta ingestion may reduce anxiety in males. Several studies have found indirect evidence for an inverse relationship between anxiety and paternal care in this and other species. The proposed work will test the hypothesis that placentophagia by male California mice reduces their anxiety, and by doing so may increase their paternal responsiveness. First-time expectant fathers and virgin males will be treated via oral gavage with placenta in oil or oil alone, or left untreated, and subsequently tested for anxiety-like behavior and paternal behavior. Plasma will be assayed for allopregnanolone (an anxiolytic steroid produced in placenta), and neural activity (Fos-immunoreactivity) will be determined in brain areas known to regulate anxiety and paternal care, to determine if placentophagia may reduce anxiety in new fathers through anxiolytic effects of alloprenanolone. Results will provide novel insights into the functional significance of placentophagia by males as well as possible influences on the activation of male parental care.
(Abstract from NSF)