Reduction of the domestic chick's fear of human beings by regular handling and related treatments

Abstract

Abstract. Fear of human beings can seriously jeopardize a chicken's welfare and performance and its reduction is therefore an important objective. The present study assessed the effects of various forms of regular human contact on subsequent avoidance of the experimenter and tonic immobility fear reactions in pair-housed, female domestic chicks, Gallus gallus domesticus. The results not only confirmed that regular gentle handling (picking up and stroking) is a potent and reliable method of reducing fear and avoidance of humans, but also illustrated the malleability of the handling process. Thus, avoidance of the experimenter was considerably reduced by each of the following treatments: (1) placing one's hand into the chicks' cage twice daily, with no attempt to initiate physical contact; (2) application of a rough-handling (suspension by the legs) regime: (3) letting chicks regularly observe their neighbours being picked up and handled; and (4) allowing visual contact with a human being who simply stood in front of and touched the wire-mesh wall of the chicks' home cage twice a day. The chicks' tonic immobility responses were also significantly shortened by treatments 1 and 3. Possible mechanisms underpinning the handling phenomenon are discussed. Although regular gentle handling of every bird is clearly not feasible in modern farming practice, the positive effects of the other experimental treatments suggest that the reduction of fear by regular human contact is extremely plastic. It is therefore considered likely to have practical application.