OLFACTORY PREFERENCES IN NEWBORN LAMBS - POSSIBLE INFLUENCE OF PRENATAL EXPERIENCE

The present study examined whether prenatal chemosensory experience in fluenced chemosensory-based orientation behaviour in newly-born lambs. Two experimental strategies were developed in order: (i) to analyse t he responsiveness of lambs to odours extracted from the prenatal envir onment (experiments 1 and 4) and to odours their were never exposed to (experiment 2), and (ii) to analyse the neonatal consequences of a pr enatal exposure to a novel odorant (experiment 3). In experiment 1, wh en simultaneously presented with amniotic fluid (AF) and distilled wat er in a double-choice test, lambs displayed a clear attraction to AF. In experiment 3, two groups of lambs received differing exposure to ci tral in utero: group 1 lambs were born to ewes fed a citral diet and g roup 2 lambs were born to ewes never exposed to citral(CI). They were assessed in a double-choice test contrasting CI and AF (experiment 2 i ndicates that CI was neither attractive nor aversive in naive lambs). Although control lambs showed a clear preference for AF over CI, those exposed to CI prenatally did not orient discriminately to either stim ulus, suggesting that prenatal experience with CI may alter postnatal responsiveness to it. Experiment 4 tested the ability of lambs to disc riminate between the chemosensory qualities of samples of own vs alien AF; lambs oriented preferentially to their own AF. These findings sug gest that prenatal chemosensory experience may be stored by lambs for some time after birth and influence their search behaviour.