Vitamin D metabolism and disorders in companion animals

Vitamin D principal role in veterinary species involves the regulation of calcium metabolism and in the development and maintenance of skeletal health. There is also a growing interest in understanding the role vitamin D plays in non-skeletal health in both human and veterinary patients. This chapter provides an update of our current understanding of vitamin D biology in dogs and cats and gives an overview of how vitamin D metabolism can be assessed in companion animals. Congenital and acquired canine and feline vitamin D disorders are discussed with a focus on recent studies, which have explored the role of vitamin D in the development and outcomes of non-skeletal diseases of companion animals.