A series of experiments was conducted to assess whether lambs are discrimin
atively responsive to Visual images of conspecifics. Lambs (3-4-week-old) c
onsistently responded with more interest and less avoidance when exposed to
a life-like image of an unfamiliar lamb, a ewe or the silhouette of a ewe,
than to a meaningless mosaic of the same conspecific stimulus. In each ins
tance, lambs preferentially sniffed the head region of the conspecific imag
e. Slides of a ewe and a dog likewise elicited differential responses by la
mbs, but there were no clear differences in their attraction to, or avoidan
ce of these two categories of stimuli. In contrast, adult ewes responded mo
re negatively to the dog image than to the ewe slide. Overall, lambs appear
ed to respond to conspecific images as social stimuli, however, social disc
rimination by visual cues alone may improve with age and experience. (C) 19
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