Date of Award:


Document Type:


Degree Name:

Master of Science (MS)



Committee Chair(s)

Carl D. Cheney


Carl D. Cheney


R. Powers


Edward Crossman


Three experiments were conducted with five species of tropical fish to investigate the phenomena of taste aversion and food neophobia. In addition, an experiment determined specifically if position in the tank could acquire conditioned aversive properties.

In Experiment 1 , four habituated fish were fed novel meat-flavored pellets on the treatment day. Six were made ill within 30, 60, or 90 minutes (2 subjects each) by intragastric administration of syrup or Epicac. The following day all were fed familiar commercial pellets. On the second day after treatment, all were offered the meat-flavored pellets. Results showed longer latencies, more tasting, and decreased consumption of novel pellets. All measures differed significantly for the treatment subjects compared to their own baseline and controls.

Experiment II demonstrated food neophobia in four in experienced fish. After habituation they were fed novel meat-flavored pellets but not made ill (day 0). On day 1 and 2 they received familiar diet and were made ill after the feeding on day 2. On day 3 they received familiar food again and no change in approach latency, testing response, or quantity consumed occurred. On day 4, they were offered the novel meat-flavored pellets which they refused. These results indicate that the fish associated the illness with the more "novel" food even though their familiar diet was temporally closer to the illness.

In Experiment III five species of naive fish were habituated to 20-gallon tanks and made ill after eating in one end and not in the other. The same food was us ed in both ends. The "illness end" could have taken on discriminitive properties and food consumption there should have decreased, as opposed to the other "safe end". The results indicated that "place" did not acquire aversive discriminitive properties. Food consumption decreased in quantity, food approach latencies increased and length of tasting bouts increased in both ends.

These experiments were the first to use these species of fish in this type of research. The results extend the phenomena of taste aversion and food neophobia. In addition, Experiment III systematically replicated the hypothesis of relevant relations between stimuli and showed that it is easier to learn certain consequences with certain cues than with others. In this case illness was quickly associated with taste but "place" was treated as irrelevant.