Ability of Lambs to Learn with a Delay between Food Ingestion and Consequences Given Meals Containing Novel and Familiar Foods
Applied Animal Behaviour Science
Burritt, E.A. and Provenza, F.D., 1991. Ability of lambs to learn with a delay between food ingestion and consequences given meals containing novel and familiar foods. Appl. Anim. Behav. Sci., 32:179-189.
We studied: (1) whether lambs could learn to avoid a novel food given delays of up to 8 h between food ingestion and gastrointestinal illness (long-delay study); (2) how gastrointestinal illness affected the selection of several foods differing in familiarity to lambs (mixed-meal study).
Gastrointestinal illness was induced by administering encapsulated lithium chloride (LiCI; 160 mg kg-1 body weight) to lambs using a bailing gun. In the long-delay study, lambs were offered a novel food for 5 min. If they consumed 10 g or more of the food, LiCI was administered 0,2,4,6, or 8 h later. Intake of the novel food was measured in 5 min trials for the next 3 days. When the delay between food ingestion and the administration of LiCI was 2 or 4 h, the lambs reduced their intake of the novel food after a single dose of LiCI. The lambs also reduced their intake of the novel food when the delay between food ingestion and the administration of LiCI was 6 or 8 h. However, LiC1 was administered twice before the lambs reduced their intake of the novel food; they were also given a stronger dose (320 mg kg-1 body weight) of LiC1 on Day 2 than on Day 1. Thus, repeated exposures, greater gastrointestinal distress, or both may be required before lambs reduce their intake of a novel food given delays of 6 h or more.