title: Effects of castration on problem behaviors in male dogs with reference to age and duration of behavior.
abstract: OBJECTIVE
  To determine whether 9 problem behaviors in adult male dogs were affected by castration and to examine the influence of age and duration of problem behavior on behavioral effects of castration.
  
  
  METHODS
  Cohort study.
  
  
  METHODS
  57 male dogs > 2 years old at the time of castration that had > or = 1 of the targeted problem behaviors.
  
  
  METHODS
  Data were collected by telephone contact with owners to identify dogs that had > or = 1 problem behavior before castration and to estimate the improvement (ie, decrease) in the objectionable behaviors after castration. Problem behaviors of interest included urine marking in the house, mounting, roaming, fear of inanimate stimuli, aggression toward human family members, aggression toward unfamiliar people, aggression toward other dogs in the household, aggression toward unfamiliar dogs, and aggression toward human territorial intruders.
  
  
  RESULTS
  Effects of castration on fear of inanimate stimuli or aggression toward unfamiliar people were not significant. For urine marking, mounting, and roaming, castration resulted in an improvement of > or = 50% in > or = 60% of dogs and an improvement of > or = 90% in 25 to 40% of dogs. For remaining behaviors, castration resulted in an improvement of > or = 50% in < 35% of dogs. Significant correlations were not found between the percentage of improvement and age of the dog or duration of the problem behavior at the time of castration.
  
  
  CONCLUSIONS
  Castration was most effective in altering objectionable urine making, mounting, and roaming. With various types of aggressive behavior, including aggression toward human family members, castration may be effective in decreasing aggression in some dogs, but fewer than a third can be expected to have marked improvement. Age of the dog or duration of the problem behavior does not have value in predicting whether castration will have a beneficial effect.
authors.affiliation: Behavior Service, Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis 95616, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Neilson
authors.forename: R A
authors.initials: RA
authors.lastname: Eckstein
authors.forename: B L
authors.initials: BL
authors.lastname: Hart
mesh_terms: D000374:Aggression / Q000502:physiology; D000375:Aging / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D015331:Cohort Studies; D004285:Dogs / Q000502:physiology* / Q000601:surgery; D008297:Male; D009919:Orchiectomy / Q000379:methods / Q000662:veterinary*; D012726:Sexual Behavior, Animal / Q000502:physiology*; D013997:Time Factors