HORMONAL INDUCTION OF MATERNAL-BEHAVIOR IN NON-PREGNANT EWES

The possibility of inducing maternal behaviour in non-pregnant ewes by injections of ovarian steroids has been investigated, using either a short course treatment (7 days) or a long term treatment (30 days). Short term treatment induced maternal behaviour with suckling in 14 out of 23 multiparous ewes and in 1 out of 13 nulliparous ewes while none of the control animals (7 multiparous and 4 nulliparous females) exhibited such a behaviour. The difference in the success of the treatment in multiparous and nulliparous females was significant. Long term treatment induced maternal behaviour in 9 out of 19 multiparous treated ewes while none of 11 ovariectomized control ewes displayed this behaviour and that 14 parturient ewes (out of 14) did. In both experiments there was a clear evidence of the establishment of a selective maternal behaviour shown by the treated ewes. © 1979.