title: Effects of a mechanical response-contingent surrogate on the development of behaviors in nursery-reared rhesus macaques (Macaca mulatta).
abstract: Nursery-reared infants have several behavioral and physiologic differences from their mother-reared counterparts. We investigated whether a response-contingent surrogate mitigated some of those differences by decreasing fearfulness and partner-clinging and increasing environmental exploration in nursery-reared infants continuously paired with a peer. Six nursery-reared infant rhesus macaques (in pairs) were given a mechanical responsive surrogate (RS), and 6 (in pairs) were given an identical but nonresponsive surrogate (NRS). The 2 treatment groups were compared and then combined into a single group of all 12 of surrogate-exposed animals (CS) that was compared with a nonsurrogate control group (NS) of 10 nursery-reared infants. Results showed significant differences between CS and NS infants but no significant differences between the RS and NRS infants. As compared with NS infants, CS infants showed less partner-clinging, less affiliation directed toward only partner, and more foraging and tactile-oral exploration of the environment. These advantageous effects support additional research to develop improved surrogate and the implementation of surrogate programs for nursery-reared infants.
authors.affiliation: Brain, Mind and Behavior Unit, California National Primate Research Center, Davis, California, USA; Animal Behavior Graduate Group, School of Veterinary Medicine, University of California, Davis, Davis, California, USA. rlbrunelli@gmail.com.
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Brunelli
authors.affiliation: Animal Care Unit, California National Primate Research Center, Davis, California, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Blake
authors.affiliation: Statistics Department, University of California, Davis, Davis, California, USA.
authors.forename: Neil
authors.initials: N
authors.lastname: Willits
authors.affiliation: Brain, Mind and Behavior Unit, California National Primate Research Center, Davis, California, USA.
authors.forename: Ina
authors.initials: I
authors.lastname: Rommeck
authors.affiliation: Brain, Mind and Behavior Unit, California National Primate Research Center, Davis, California, USA; Department of Population, Health, and Reproduction, School of Veterinary Medicine, University of California, Davis, Davis, California, USA.
authors.forename: Brenda
authors.initials: B
authors.lastname: McCowan
mesh_terms: D000822:Animal Husbandry; D000818:Animals; D001522:Behavior, Animal; D005260:Female; D008253:Macaca mulatta / Q000502:physiology*; D008297:Male; D012919:Social Behavior; D013315:Stress, Psychological