Mother-young mutual recognition in Columbia sheep with nutritional restriction during pregancy

摘要

It was evaluated in multiparous Columbia ewes their ability to recognize their offspring (8 or 12 h postpartum), and in lambs their ability to recognize their mothers (12 or 24 h after birth), plus the spectral characteristics of the bleating of the litter (24 and 48 h of age). There were two experimental groups, one with nutritional restriction during the second half of gestation (Restricted, 70 % of their requirements in protein and energy from d 70 post conception, n= 24) and another without nutritional restriction (Control, 100 % of their requirements during pregnancy, n= 11). Nutritional restricted mothers to 8 h, showed no ability to discriminate the own and alien lamb (P>0.05), but at 12 h, they could do so. While control females were able todiscriminate its own lamb from an alien one since 8 h, they spent more time near their offspring than the others and looked them for longer period (P<0.05). While lambs from restricted group at 12 h were not able to discriminate against an alien mother(P<0.05), but they could do so at 24 h. While lambs of control group were able to discriminate against an alien mother since 12 h after birth (spend longer time near their mother and looked for longer time compared to the alien dam, P<0.05). The spectralcharacteristics of the vocalizations of the lambs were not influenced by the nutritional treatment of their mothers during pregnancy P<0.05). It was concluded that nutritional restriction during gestation delays the recognition mother-lamb, without alters apparently the spectrum of vocalizations in lambs.