And for your last comment,
Vitamins and minerals are also very important in the canine athlete. Some important vitamins are A, D, E, K, and the B-complex vitamins, especially thiamin, niacin, and cyanocobolamine (B1, B3, and B12). Vitamin A plays a role in ligament and tendon health. Vitamin D is important in maintaining the calcium and phosphorus balance. Vitamin E is a very important anti-oxidant. It acts to maintain cell membrane stability, which is very important in dogs that use their olfactory senses, i.e. pointing breeds, detector dogs, and search and rescue dogs. Vitamin K is important to maintain proper blood conditions in the canine athlete. Thiamin helps to minimize the effects of stress related to competition and performance. Niacin aids in carbohydrate metabolism, and is required for red blood cell production. Cyanocobolamine is essential for synthesis of protein and formation of red blood cells and hemoglobin. Most vitamin needs are met with a normal high quality diet, but in certain situations supplementation can be beneficial to performance.