The effect of flavor concentration and toxin dose on the formation and generalization of flavor aversions in lambs.

If an animal experiences gastrointestinal malaise after eating a novel feed, it develops a dislike for the feed called a conditioned flavor aversion (CFA). Understanding flavor aversions is important for diet-training procedures, understanding animal responses to poisonous plants, and preparing animals for new foraging environments. Our research objectives were to determine how variation in 1) flavor concentration (oregano) and 2) dose of gastrointestinal toxin (lithium chloride; LiCl) affected the establishment of CFA in lambs. In a series of experiments feeding lambs ground grains mixed with oregano, we examined how the formation of a CFA to one ground grain, with or without oregano, influenced the consumption of another oregano-flavored grain. We determined that 1) the higher the toxin dose, the stronger the CFA, the greater the generalization of the CFA to a similar feed, and the greater the avoidance of a novel feed; 2) lambs generalized aversions from familiar to novel feeds when both feeds had a flavor in common; and 3) the concentration or intensity of feed flavor apparently did not affect the acquisition or generalization of a CFA, but it did influence the acceptance of a novel feed. Our findings suggest that flavor aversions may be important in the acceptance of harvested or processed feeds.