Association Between Protein Content in Dry Dog Food and Aggression in Golden Retriever Dogs

The objective of this study is to evaluate the relationship between protein content in commercially available dry food and behavioral scores collected via a validated behavior questionnaire. Health and lifestyle factors were obtained from owner-completed questionnaires for golden retrievers participating in a prospective canine health study, eating commercially available dry food as ≥80% of the daily intake. Diets were categorized as high (≥30%), medium (21-29%), or low (≤20%) protein levels. Ten behavioral outcomes from a validated survey were used as outcome measurements. The association of dietary protein level and behavior outcomes were estimated using logistic regression, adjusting for sex, reproductive status, and dog's primary lifestyle. Compared with dogs fed medium-protein diets, dogs fed high-protein diets were 1.3 times more likely to have dog rivalry (95% CI, 1.02-1.78). The dogs fed low-protein diets were 1.4 times more likely to have separation-related behavior (95% CI, 1.01-2.03). When assessing and treating aggression and separation related-behaviors, clinicians should evaluate and weigh the importance of several factors, including the diet being fed.