Vitamin C is not normally essential for dogs as they synthesise their own. However, some researchers suggest that vitamin C synthesis in dogs may be inadequate on a low protein diet and a few individuals may not be able to synthesise the vitamin and so require it in the diet. These foods need to be balanced with higher calcium foods to prevent calcium deficiencies. Phytic acid in cereals may also reduce calcium absorption. Soaking grains overnight is believed to activate enzymes which break down the phytic acid.
Vitamin D is essential for calcium absorption.
Seaweed, eg kelp powder, eggs , whole grain rye and wheat, lettuce. Other minerals are generally well provided in a diet containing a variety of vegetables, fruit, nuts , milk , cheese , eggs . If your dog has been brought up on a meat diet, make the changeover to a vegetarian diet gradual. With active dogs there is a problem of bulk versus energy and readers are advised to consult their vet for guidance to ensure that sufficient energy can be obtained from the mass of food given. Milk alone is not an adequate source of calcium for puppies and a mineral supplement of calcium phosphate is recommended.