Surgical removal of the pregastric pouch reduces voluntary lactose consumption in golden hamsters.
Unlike other adult mammals, golden hamsters voluntarily consume substantial amounts of the disaccharide sugar lactose. It was hypothesized that the hamster's readiness to consume lactose depends upon its possession of a pregastric pouch in which ingested lactose is broken down into its constituent monosaccharides, thus preventing the aversive gastrointestinal symptoms that monogastric animals experience following lactose ingestion. Adult golden hamsters underwent either surgical removal of the pregastric pouch or sham surgery. Following recovery from surgery, hamsters were given continuous free access for 14 days to tap water, Purina Rodent Chow, a 24% sugar solution (either lactose or sucrose), and a Purina chow-based diet containing 30% added sugar (for each hamster, the same sugar that was provided in solution). Surgical removal of the pregastric pouch caused a 40% reduction in total lactose consumption: this reduction resulted from equivalent decreases in consumption of the lactose solution and the lactose-containing diet. Pouch removal had no effect on total sucrose consumption, and sham surgery had no effect on either lactose or sucrose consumption. These results support the conclusion that the adult hamster's unusually high level of voluntary lactose consumption depends upon its possession of a pregastric pouch, which plays an important role in lactose digestion.
DiBattista
D
D
Psychology Department, Brock University, St. Catharines, Ontario, Canada.
Robillard
M
M
D000818:Animals; D006224:Cricetinae; D004063:Digestion / Q000502:physiology*; D002149:Energy Intake / Q000502:physiology; D005518:Food Preferences / Q000502:physiology; D007785:Lactose / Q000008:administration & dosage* / Q000378:metabolism; D008297:Male; D008647:Mesocricetus; D013270:Stomach / Q000502:physiology*; D013649:Taste / Q000502:physiology*
D007785:Lactose