Preferred Flavors and Performance of Weanling Pigs

To characterize the flavor preferences of weanling pigs, a T-maze test was designed and validated. After having sampled feed from one side, containing flavor, and the other side, containing no flavor, pigs were allowed to select feed from either side of the T-maze five times. The frequency of selecting the flavored feed and the percentage of total feed eaten in 20 s/run were used to establish degree of preference for flavors. A total of 129 flavors or flavor combinations was tested in 248 trials, with some flavors tested at several concentrations. At least four flavors were tested in each of eight major flavor groups; the frequency distribution of preference did not differ among groups. Five specific flavors, highly preferred by the pigs in the T-maze tests, were selected for sustained preference tests for two 5-d periods. In the tests, a preference was shown for three of the five flavors. Two flavors were then tested for effects on performance using three groups of 10 pigs for 5 wk after weaning. The feed intakes and body weight gains were increased during the first week in both groups fed flavored feed compared with those of the control group. In a growth trial with 1,219 pigs, one of the two flavors increased feed intake and improved weight gain during the first week after weaning. Thus, although pigs did not appear to prefer flavors in any one of the groups tested, they did prefer specific flavors, which, when added to feed, improved feed intake and weight gain during the critical first week after weaning.