title: Development of social familiarity in ewes.
abstract: We assessed the development of individual discrimination resulting from direct contact/familiarization in ewes. Unfamiliar ewes were introduced during 6, 24 or 72 h in groups of already familiarized ewes. At the end of this contact period, the development of social recognition with the animal that has been introduced was assessed using two different types of tests: a Y-maze preference test and a delayed paired close encounters test where tested ewes are successively and randomly interacting with the familiar animal and an unfamiliar conspecific. The results of both tests showed that ewes developed a recognition of the familiar animal in comparison to a completely unfamiliar female. However, this preference was evidenced after 24 h of contact when using the paired close encounters test whereas it appears only after 72 h when using the Y-maze test, suggesting that the paired close encounters test is a more sensitive methodology to assess the development of social familiarization. The importance of estrogens, in the formation of social familiarization was also evaluated. To this end, social recognition in the paired close encounters test was compared between ovariectomized animals receiving estrogen implants or not. Despite significant high levels of estradiol in estrogen implanted females, no major differences in recognition appeared between groups, suggesting that in our conditions estrogens do not have major influence on social familiarization.
authors.affiliation: INRA, UMR85 Physiologie de la Reproduction et des Comportements, F-37380 Nouzilly, France. mkeller@tours.inra.fr
authors.forename: Matthieu
authors.initials: M
authors.lastname: Keller
authors.forename: Fabien
authors.initials: F
authors.lastname: Cornilleau
authors.forename: Eric
authors.initials: E
authors.lastname: Archer
authors.forename: Frédéric
authors.initials: F
authors.lastname: Lévy
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology; D004958:Estradiol / Q000097:blood; D004967:Estrogens / Q000008:administration & dosage; D005260:Female; D006041:Goats / Q000502:physiology* / Q000523:psychology*; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology; D009830:Olfactory Bulb / Q000187:drug effects / Q000502:physiology; D010052:Ovariectomy; D021641:Recognition, Psychology / Q000502:physiology*; D012919:Social Behavior; D013997:Time Factors
chemical_list: D004967:Estrogens; D004958:Estradiol