This study investigates the impact of adding zinc and/or linoleic acid in a complete and balanced diet on the skin and haircoat condition of adult dogs. During eighteen weeks, animals consumed a standard diet for nine weeks and a supplemented diet for the remainder. Quantitative assessments of skin and haircoat condition were made after nine and eighteen weeks. Results showed dogs on the supplemented diet had a significantly improved coat gloss and scale compared with the standard diet. Additionally, there was a significant decrease in transepidermal water loss for dogs supplemented with zinc only or in combination with linoleic acid.