Effect of dietary protein content on behavior in dogs

Objective-To determine the effect that feeding diets containing a low (17%), medium 25%), or high (32%) protein content would have on behavior in dogs. Design-Prospective, controlled study. Animals-12 dogs with dominance aggression, 12 dogs with hyperactivity, 12 dogs with territorial aggression, and 14 control dogs without behavioral problems. Procedure-Dogs were fed each of the diets for a 2-week period, and owners were instructed to score their dogs' behavior on a daily basis. Results-Behavior of the dogs with dominance aggression, dogs with hyperactivity, and control dogs was unchanged by the dietary manipulations. Territorial aggression was significantly reduced when dogs were fed the low- or medium-protein diet, compared with territorial aggression when fed the high-protein diet. Post hoc analysis indicated that this effect was attributable to a marked reduction in aggression in a subset of the group (n = 7) in which territorial aggression was a result of fear. Clinical Implications-Results of this study suggest that a reduction in dietary protein content is not generally useful in the treatment of behavior problems in dogs, but may be appropriate in dogs with territorial aggression that is a result of fear.