A main nutrient source for foals before the initiation of creepfeeding or weaning is mare’s milk. The epiphysitis in nursing foals has been frequently found in Hidaka district of Hokkaido Island. The incidence of the epiphysitis is thought to be due to rapid growth, imbalance of mineral intake, or deficiencies for Zn and Cu intake. The purpose of the present experiment is to clarify the intakes of trace minerals and nutritional status in mares and their suckling foals in Hidaka district.
Cu and Zn contents in milk were continuously decreased after parturition, which induced the lower intake of these minerals in their foals. Serum Cu concentrations were not changed after parturition in mares, and the levels were within a normal range.
Serum Cu concentrations were abnormally low in foals in 1 week after birth but recovered to the normal level in 3 weeks. Serum Zn concentrations were lower than the normal level in mares and their foals through the experimental period. These results suggested that mares and foals became Zn deficiency in this area. Zn deficiency induced by low Zn concentration in milk might cause the epiphysitis of foals.
