title: Food Deprivation, Body Weight Loss and Anxiety-Related Behavior in Rats.
abstract: In behavioral studies, food deprivation protocols are routinely used to initiate or maintain motivational states that are required in a particular test situation. However, there is limited evidence as to when food deprivation compromises animal welfare. This study investigated the effects of different lengths of food deprivation periods and restricted (fixed-time) feeding on body weight loss as well as anxiety-related and motivated behavior in 5-6 month old male and female Wistar rats. The observed body weight loss was not influenced by sex and ranged between 4% (16 h deprivation) to approximately 9% (fixed-time feeding). Despite significant body weight loss in all groups, the motivation to eat under the aversive test conditions of the modified open field test increased only after 48 h of food deprivation. Long-lasting effects on anxiety as measured in the elevated plus maze test 24 h after refeeding have not been observed, although fixed-time feeding could possibly lead to a lasting anxiogenic effect in female rats. Overall, female rats showed a more anxiolytic profile in both tests when compared to male rats. Despite these sex differences, results suggest that food deprivation is not always paralleled by an increased motivation to feed in a conflict situation. This is an important finding as it highlights the need for tailored pilot experiments to evaluate the impact of food deprivation protocols on animals in regard to the principles of the 3Rs introduced by Russell and Burch.
authors.affiliation: Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstr. 20, Berlin 14195, Germany. silke.dietze@fu-berlin.de.
authors.forename: Silke
authors.initials: S
authors.lastname: Dietze
authors.affiliation: School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK. katarinalees90@gmail.com.
authors.forename: Katarina R
authors.initials: KR
authors.lastname: Lees
authors.affiliation: Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstr. 20, Berlin 14195, Germany. heidrun.fink@fu-berlin.de.
authors.forename: Heidrun
authors.initials: H
authors.lastname: Fink
authors.affiliation: Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstr. 20, Berlin 14195, Germany. jan.brosda@fu-berlin.de.
authors.forename: Jan
authors.initials: J
authors.lastname: Brosda
authors.affiliation: School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK. peter.voigt@nottingham.ac.uk.
authors.forename: Jörg-Peter
authors.initials: JP
authors.lastname: Voigt
keywords: body weight; elevated plus maze; food deprivation; modified open field; rat; welfare