Given their large size, Bouviers des Flandres require a balanced diet rich in high-quality protein to support muscle maintenance and overall health. It's essential to provide appropriate portions to avoid obesity, a common issue in large breeds. Consider feeding them multiple smaller meals daily to reduce the risk of bloat, a potentially fatal condition. Ensure their diet includes essential fatty acids for coat health and joint supplements like glucosamine and chondroitin to support their joints. Regular consultations with a veterinarian help tailor their diet to their specific age, activity level, and health needs.