Meeting Abstract

P2.6  Sunday, Jan. 5 15:30  Interindividual variation in hamster hoarding behavior likely due to maternal effects, not additive genetic variation BROZEK, J.B.*; SCHNEIDER, J.E.; Lehigh University jmb408@lehigh.edu

Acquisition of nutrients from the environment is critical to survival and reproduction. Associated behaviors like appetite may represent plastic responses to internal and external cues. Consistent differences among species and populations in behaviors like food hoarding suggest an underlying genetic component, and that selection can act on variation in hoarding in wild populations. We use Syrian hamsters Mesocricetus auratus as a model system to understand neuro-endocrine mechanisms associated with the switch between food and sex behavior. We observe consistent variation in hoarding among individuals acquired from breeding colonies, and within stocks produced in our lab. Within individuals, hoarding behavior is repeatable. We test the hypothesis that inter-individual variation is due to additive genetic variance using a pedigreed population of hamsters representing a mix of three ancestral stock populations. We established a heterogeneous stock as a 3-way cross, and tested hoarding behavior over 4 days, ending on postnatal day (PND) 90. Tested animals were randomly mated, avoiding sibling pairs. We use parent offspring regression and ANOVA to estimate heritability and additive genetic variance. An animal model was used to evaluate the contribution of several factors to observed variance. We found little evidence for additive genetic variance contributing to hoarding behavior in laboratory bred hamsters. We suggest that maternal effects, possibly through gestational programming, likely contribute significantly to variation in appetitive ingestive behaviors in laboratory derived hamsters. Accounting for this variance may play a role in the interpretation of data from neuro-endocrine studies attempting to understand the underlying mechanisms associated with food hoarding.