title: The impact of moderate daily alcohol consumption on aggression and the formation of dominance hierarchies in rats.
abstract: OBJECTIVE
  Group-housed male rats form social hierarchies, and under these conditions, it has been reported that subordinate (SUB) rats consume more alcohol than dominant (DOM) rats. We tested the hypothesis that a history of drinking alcohol would cause SUB rats to consume even greater amounts of alcohol.
  
  
  METHODS
  Male Long-Evans rats were trained to drink 10% alcohol or a sucrose/quinine solution equal in calories for 1 h/day using a sucrose-fading procedure. Subsequently, rats were housed in colonies (four males, two females) in a visible burrow system (VBS) for 14 days. Individual control male rats were housed in a tub cage with one female. Rats were removed from the VBS (or control environment) daily and given 1 h to drink alcohol or sucrose/quinine.
  
  
  RESULTS
  Colonies given daily access to sucrose/quinine formed clear DOM/SUB relationships in all measured parameters. Alcohol-drinking colonies failed to establish a dominance hierarchy and displayed little aggression, with an average of 14.6 +/- 6.1 offensive attacks compared with 58.5 +/- 12.3 attacks carried out by DOM sucrose/quinine rats. During VBS housing, alcohol and sucrose/quinine intake decreased independent of housing environment or social status.
  
  
  CONCLUSIONS
  Contrary to prior reports of the effect of alcohol on aggressive behavior, moderate daily alcohol intake before and during VBS housing reduced aggression and precluded the formation of a dominance hierarchy in rats.
authors.affiliation: Program in Neuroscience, University of Cincinnati, Cincinnati, OH, USA. duncanel@mail.nih.gov
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Duncan
authors.forename: Kellie L K
authors.initials: KL
authors.lastname: Tamashiro
authors.forename: Mary M N
authors.initials: MM
authors.lastname: Nguyen
authors.forename: Stacy R
authors.initials: SR
authors.lastname: Gardner
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Woods
authors.forename: Randall R
authors.initials: RR
authors.lastname: Sakai
mesh_terms: D000374:Aggression / Q000187:drug effects*; D000428:Alcohol Drinking / Q000523:psychology*; D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D002492:Central Nervous System Depressants / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D003345:Corticosterone / Q000097:blood; D003624:Darkness; D004327:Drinking Behavior / Q000187:drug effects; D000431:Ethanol / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D008027:Light; D008297:Male; D011803:Quinine / Q000008:administration & dosage; D051381:Rats; D020318:Rats, Long-Evans; D012054:Reinforcement, Psychology; D012646:Self Administration; D012930:Social Dominance; D013395:Sucrose / Q000008:administration & dosage; D013739:Testosterone / Q000097:blood; D013997:Time Factors
chemical_list: D002492:Central Nervous System Depressants; D000431:Ethanol; D013739:Testosterone; D013395:Sucrose; D011803:Quinine; D003345:Corticosterone