Taste threshold determination and side-preference in captive cockatiels (Nymphicus hollandicus)

The taste thresholds of caged cockatiels (Nymphicus hollandicus) for aqueou s solutions of sodium chloride, citric acid, acid sucrose were studied usin g two-choice taste-preference tests. The effects of location on the thresho ld were tested by putting the flavored solution in either the preferred or non-preferred locations (i.e. sides of cages) and offering water in the opp osite location. Four parameters (total consumption, consumption from prefer red side, consumption from non-preferred side, and proportion of test solut ion consumed) were measured at the end of 3-day test periods. Experiments w ere repeated with increasing concentrations of test flavors until intake va riables were significantly (p < 0.05) affected. The results showed that bir ds distinguished (p < 0.05) between purified water and 0.16 mol l(-1) sodiu m chloride, 0.36 mol l(-1) sucrose, or pH 5.5 citric acid. The likelihood o f detecting a taste threshold was greater for sodium chloride and citric ac id when these solutions were placed on the preferred side. In contrast, suc rose sensitivity was greater when this solution was offered on the non-pref erred side. (C) 2000 Elsevier Science B.V. All rights reserved.