Research Article Altered Feeding Behaviors and Adiposity Precede Observable Weight Gain in Young Rats Submitted to a Short-Term High-Fat Diet DavidE.Andrich , 1,2,3 LilyaMelbouci, 1,2,4 YaOu , 1,2,4 Jean-PhilippeLeduc-Gaudet , 1,2,4 FrançoisChabot , 1,2,4 FrançoisLalonde , 1,2,4 F´ abioSantosLira, 1,2,5 BruceD.Gaylinn , 6 GillesGouspillou, 1,2 GawiyouDanialou , 1,7 Alain-SteveComtois, 1,2 andDavidH.St-Pierre 1,2,4 1 D´epartement des Sciences de l’Activit´ e Physique, Universit´e du Qu´ ebec ` a Montr´eal (UQAM), 141 President-Kennedy Ave., Montr´ eal, QC, Canada H2X 1Y4 2 Groupe de Recherche en Activit´ e Physique Adapt´ ee (GRAPA), UQAM, 141 President-Kennedy Ave., Montr´ eal, QC, Canada H2X 1Y4 3 D´ epartement des Sciences Biologiques, UQAM, 141 President-Kennedy Ave., Montr´ eal, QC, Canada H2X 1Y4 4 Centre de Recherche du CHU Sainte-Justine, 3175 chemin de la Cˆ ote-Sainte-Catherine, Montr´ eal, QC, Canada H3T 1C5 5 Department of Physical Education, São Paulo State University, 19060-900 Presidente Prudente, SP, Brazil 6 Department of Medicine, University of Virginia, 450 Ray C. Hunt Drive, Charlottesville, VA 22903, USA 7 Royal Canadian Military College, 15 Jacques-Cartier Nord, Saint-Jean-sur-Richelieu, QC, Canada J3B 8R8 CorrespondenceshouldbeaddressedtoDavidH.St-Pierre;david.stpierre.uqam@gmail.com Received 31 October 2017; Accepted 28 February 2018; Published 1 April 2018 AcademicEditor:LuigiSchiavo Copyright © 2018 David E. Andrich et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Informationregardingtheearlyeffectsofobesogenicdietsonfeedingpatternsandbehaviorsislimited.Toimproveknowledge regardingtheetiologyofobesity,youngmaleWistarratsweresubmittedtohigh-fat(HFD)orregularchowdiets(RCDs)for14 days. Various metabolic parameters were continuously measured using metabolic chambers. Total weight gain was similar between groups, but heavier visceral fat depots and reduced weight of livers were found in HFD rats. Total calorie intake was increasedwhileindividualfeedingboutswereshorterandofhighercalorieintakeinresponsetoHFD.Ambulatoryactivityand sleepdurationweredecreasedinHFDratsduringpassiveandactivephase,respectively.Acylatedandunacylatedghrelinlevels wereunalteredbytheincreasedcalorieintakeandtheearlychangesinbodycomposition.isindicatesthatatthisearlystage,the orexigenicsignaldidnotadapttothehigh-caloriecontentofHFD.Weherebydemonstratethat,althoughtotalweightgainisnot affected, a short-term obesogenic diet alters body composition, feeding patterns, satiation, ambulatory activity profiles, and behavioursinayoungratmodel.Moreover,thiseffectprecedeschangesinweightgain,obesity,andensuingmetabolicdisorders. 1.Introduction Obesityandensuingmetabolicdysfunctionsaremajorissues for public health authorities [1–3]. is is of particular concern in pediatric populations in Canada where excess weightandobesityhavereachedtheprevalenceof20%and 13%, respectively [4]. Early adoption of detrimental be- haviors such as overeating, consumption of energy-dense foods,andlackofphysicalactivitypromoteexcessiveweight gain.isislikelytohaveamajorimpactinlaterlifestages since 85% of obese children become obese adults [5, 6]. Further, the initial mechanisms promoting obesity and ensuing metabolic complications remain to be better characterizedbyusingdynamicexperimentaldesignsrather than classical static protocols. is highlights the relevance ofusinganimalmodelstocharacterizetheearlystepsleading Hindawi Journal of Nutrition and Metabolism Volume 2018, Article ID 1498150, 10 pages https://doi.org/10.1155/2018/1498150