Joumrl ol' ('ornparativc l)svchology 2(X)7. Vol. Ill. No. l. l()9 ll2 Firstcontacts. in particular first sucklings. aregcnerally consid- ered an important event in mother-young bondingboth in humans and in other mammals. Successlul llrst sucklingis an important step in ensuring a young mammal's survival but, in addition, could be crucialfor thc development of a securc attachment (Ainsworth, Blehar, Waters, & Wall. 1978). This studyinvcstigates this ques- tion in hclrses, an interesting species bccause. as in other precocial species, mother-young bonds arc established rapidly, during the first hours lbllowing parturition (Crowcll-Davis & Weeks, 2005). ancl an interesting animal model because marcs generally givc birth to only one young, which implies no interl'erence fiom siblings. Much more is known about matcrnal bchavior in precocial nrammals thanabout thedevelopment of bonding by young to their mothers. Suckling appears to be essential fbr lambs (Goursaud & Nowak. 1999;Nowak et al.. 1997)and human babies (Noirot & Alegria, 1983). among other species (Blass.1990). In lambs. the first fèw suckling sequcnces are crucial fbr the development of a motherpref-erence, which appears to be mediated by properties of colostrum(Goursaud & Nowak, 1999). Pregnant fèmales of most ungulatesocial species tend to leave their group when the time of parturition nears. A possible adaptive Martine Hausberger, Séverine Henry, Claire Larose, and Marie-Annick Richard-Yris, UMR CNRS 6-5-52 Ethologie,Evolution. Ecologie,Univer- sité de Rennesl. Rennes, France. The Comité d'OrientationScientifique et Technique des HarasNation- aux supported this study fïnancially. We arc very gratefulto J. S. Rosen- blatt lbr his critical reading ol a drali ol this articlc and advice. We also thank A. Cloarecfor correcting the English and H. Schuelke. S. Du{resne , antJC. Lunel lbr helping to preparethe article. We thank Y. Lamotte (Haras de Roulefort) and S. Monteil (Harasde La Ganel for allowing us to study on their breedingfarms. Correspondence concerning this article shouldbe addressed to Martine Hausberger, UMR CNRS 65-52 Ethologie. Evolution,Ecologie, Université de Rennesl, Avenue du Cénéral Leclerc, Campusde Beaulieu. F-35042 Rennes, Cedex, France. E-mail : mar1ine.hausberger@ univ-rennes I .fr Copyright 2{X)7hy the Amorican l)sycholtrgical Association 0735-71).1(r/07/:il1.(X) IX)l: Il).lOiil0735-7036.l2l.l.I0t) lunctionlor socialisolation may be that it is a way of prevcnting conspecifics liom interlering with bonding betwcenmothcr and young (Crowell-Davis & Weeks,2005). Interlèrcnce by conspe- ciflcs can lead to problems for mot.her-young bonds in primate societies (Fairbanks, I 996). However. interlèrences around first suckling arc frequentboth in human neonatal settings and among domestic animals. We hypothesized that if lirst sucklingis a crucial event in bonding. interf-ercnce at that tinte may have lasting cffects in tcrms of bonding and attachment. Secureattachment both in human and nonhuman primatcs is characterized by highcr levelsof explora- tion, play, and distance initiatives fiom the mother (Ainsworthet al.. 1978: Fairbanks, 1996). Foalstend to initiate distancing from theirdams(Crowell-Davis. 1986; WoltT & Hausberger, 1994), and both distancefiom the dam and the tendencyto play have been shown to be good predictors of sensitivityto social separation and reactions to novel objectsat later ages(Hausberger, Brudcrer,Le Scolan. & Lunel. 2006). To test this hypothesis.first. we observed the behavior ot' 3-month-oldlbals on f-arms that have developed a routine proce- dure in which the caretaker brings fbals to thc leat to elicit a rapid first suckling. Second,to avoid any bias related to potentially weaker animals being handled preferentially. we used an experi- mcnt that submitted randomlychosenlbals to the sameprocedure within the first half hour after birth. Most newborn lbals start sucklingwithin 2 hr afier birth (Waring, 1983). When observing them later in paddockswith their dams. we focused particular attention on mare-fbal distancc. Method Subjects A total of 36 young horses (Equus caballus) were used. StudvL Eighteen young horses (9 males,9 tèmales). all born on the same breeding farm nearRennes, in France, were observed. They all belonged to the same breed(French Saddlebred) and were First Suckling:A Crucial Event for Mother-Young Attachment? An Experimental Study in Horses (Equus caballus) Martine Hausberger, Séverine Henry,Claire Larose, and Marie-AnnickRichard-Yris Université de I{cnnesI This study invcstigales the consequcnces ol'intert'ercnce during lirst sucklinglbr subsequent mare-young attachnrcnt in horses (Equus t'ubullus). Foals brought to thcir dams' tcats appeared, at later ages (l-3 months), to remaincloser to their damsand to play lcssthtn control lbals that had been allowcd to sucklc spontancously. Higher lcvels of play an<I distance initialivesfrom the motherare considered critcria lbr secure attachmcnt in horses. humans, and other species. As this uniquehandlingwas the only event that distinguished experimental tiom control groups,the authorsconcludedthat trrst suckling is a crucial cvcnt in the development of secure dam-young attachmcnt. These results could havc important impli- cations lbr all nramnarl specics, including humans. Keyvt'rtrd.t : suckling, attachment, horse. mother-young bond 109