Food intake in baboons: effects of diazepam

Food intake of four adult male baboons (Papio c. anubis) was monitored during daily experimental sessions lasting 22 h. Food was available under a two-component operant schedule. Following completion of the first "procurement component" response requirement, access to food, i.e., a meal, became available under the second "consumption component" during which each response produced a 1-g food pellet. After a 10-min interval in which no response occurred, the consumption component was terminated. The effects of diazepam (DZP: 0.12-4.0 mg/kg) were determined by having the baboons drink a dose on Tuesdays and Fridays 45-60 min before the daily session. DZP produced dose-dependent increases in food intake in three of the four baboons. DZP increased the size of the first two meals and total duration of eating, but had no effect on eating rate or the number of meals within a session. The effect of DZP on the topography of feeding of baboons differs from previous reports on the effects of benzodiazepines on the topography of feeding in rodents. This suggests that species or procedural differences influence the effects of DZP on food intake.