Master of Science (MSc)
Faculty of Science
Roelof (Rudy) Eikelboom
My advisor provided support and helped edit my thesis.
Nondeprived rats receiving every 3rd day access (E3DA) to 4% sucrose solution consume more sucrose on access days compared to rats with everyday access (EDA). Rats receiving EDA or E3DA to 16% sucrose do not consume different amounts, but if placed on every 2nd day access (E2DA) to 4% sucrose E3DA-group rats consume more than EDA rats (Eikelboom, Hewitt, & Adams, 2022). E3DA affects rats’ value of sucrose but effects appear hidden with high sucrose concentrations. Valyear and Eikelboom (2021) suggested that calorie ceilings limit E3DA-induced consumption with high sucrose, but this ceiling could also be caused by increased sweetness. Are rats increasing consumption for calories, or taste?
Experiment 1 found two highly sweet but calorically different solutions that were similarly preferred in rats: 4% sucrose solution sweetened with calorie-free 0.2% saccharin, and 12% sucrose. Experiment 2 placed rats on EDA or E3DA to 4% sucrose, 4% sucrose + 0.1% saccharin (4S solution), or 12% sucrose for 34 days followed by 16 days of E2DA to 4% sucrose. Rats receiving E3DA to 4% sucrose or 4S solution consumed more than their respective EDA counterparts, but rats receiving E3DA to 12% sucrose did not. All E3DA rats consumed large amounts of 4% sucrose in the E2DA phase despite decreases in solution sweetness for rats that received 4S solution and 12% sucrose earlier. Placing rats on E3DA to calorically and hedonically different solutions induced similar lasting effects. Thus, intermittency increases rats’ consumption, but effects can be masked by caloric limits; not taste.
Folmer, Jarret and Eikelboom, Rudy, "Intermittent sucrose access: Sweetness versus calories" (2023). Theses and Dissertations (Comprehensive). 2567.