Feeding preferences in lambs influenced by prenatal flavour exposure

The aim of the present study is to highlight and evaluate the role of flavour prenatal exposure in postnatal feeding preferences in sheep after weaning and until the early stages of puberty. 16 lambs were selected from two groups of ewes; the first group was fed with a control diet, consisted of concentrated feed and alfalfa hay and the second group with the same diet, with the only difference that the concentrate was supplemented with oregano essential oil (1 ml/kg), during the period of pregnancy (50th-130th day). Lambs were later individually subjected to feeding preference tests, at the age of 3, 4.5, 6, 7.5 months old. Each test lasted 25 min and it was a free choice situation between 3 different test feeds supplemented with eucalyptus or orange or oregano essential oil (1 ml/kg). Lambs born to oregano-treated ewes ate higher amounts of the oregano supplemented test feed during all feeding preference tests compared to lambs from the control group (P<0.01). Rates for occurrences and duration of eating were also greater in lambs born to oregano-treated ewes than the offspring of the control ewe group (P<0.01). On the other hand, animals without a flavour exposure precedent did not exhibit an evident strong preference for a specific test feed, although orange supplemented feed tended to be more preferable compared to the other offered feeds. Average total intake of lambs were not different between groups during all feeding preference tests at 3, 41/2, 6 and 71/2 months old. As it is concluded, prenatal exposure to oregano essential oil via maternal ingestion drastically influences lamb feeding preferences till adulthood. (C) 2007 Elsevier Inc. All rights reserved.