Vascularization of the transplanted bone tissue is a key factor for success and precedes the formation of bone tissue. Vascularized bone grafts have been widely used in bone transplantation for their efficiency. Maturation of the bone tissue at the place of the transplant involves the change in the vascular patterning, from plexiform irregular vascular networks, to regular, polygonal networks following the structure of osteons. Seven dogs were performed bone transplantation and intravenous injection with China ink in order to highlight the network of blood vessels during bone formation at the place of the transplant. The area occupied by blood vessels increased during osteogenesis, and their length decreased in evolution, suggesting a maturation of the vascular pattern.