Taste aversion learning in suckling and weanling pigs

Pigs are able to learn to avoid a novel flavor that has previously been associated with gastrointestinal malaise. Suckling pigs were allowed to nurse from maple syrup coated teats and then were injected with 0.3 M LiCl i.p. Littermates controls were injected with 0.9% NaCl. Three days later the LiCl treated piglets did not ingest as much milk from maple syrup coated teats as their littermate controls. Weanling pigs were treated with 0.05 mg/kg apomorphine i. v. or 0.3 M LiCl 5 ml/kg intraduodenally immediately after their first meal of maple flavored feed. When maple flavored feed was offered to them again several days later they ate less than they did initially and less than controls which had been treated with 0.9% NaCl after their first maple flavored meal. The implications of taste, aversion learning in pigs for both research and swine production are discussed.