Social grouping tendencies and separation-induced distress in juvenile sheep and goats.
Social affinities in juvenile sheep and goats were compared by measuring grouping tendencies and separation-induced distress during experimental encounters with a person in either the presence or the absence of juvenile pen-mates. When tested with pen-mates, sheep spent more time near penmates than did goats. When separated from pen-mates, locomotor activity and plasma corticosteroid titers were higher in sheep, whereas vocal rates were higher in goats. Proximity to pen-mate scores were not correlated with either vocal rates, r = 0.20, or locomotion scores, r = 0.21, recorded when juveniles were tested alone. Proximity to pen-mate scores were correlated with posttest corticosteroid titers, r = 0.70; juvenile sheep spent more time near pen-mates and showed greater adrenocortical responses when temporarily separated from juvenile pen-mates. These findings support the possibility that interspecies differences in emotional reactivity contribute to the differences in grouping tendencies these ungulates display in natural or relatively unrestricted social groups.
Lyons
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Department of Animal Science, University of California, Davis.
Price
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Moberg
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D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D003863:Depression / Q000523:psychology; D005260:Female; D006041:Goats; D008124:Locomotion; D009769:Object Attachment; D012756:Sheep; D012951:Socialization; D013315:Stress, Psychological; D014743:Videotape Recording; D014828:Vocalization, Animal