Clinicopathological Findings on White Muscle Disease in Aborted Fetuses and Premature Foals

Abstract

In order to elucidate fetal white muscle disease, mares and their aborted fetuses and premature or newborn foals were divided into three groups and examined. Group I (16 cases) included mares uninjected with E·SE and their aborted fetuses and premature foals. Group II (3 cases) included mares injected with E·SE (containing selenium 2.5 mg/ml and α-tocopherol acetate 50 mg/ml) and their aborted fetuses or premature foals. Horses of Group I and Group II were light horses from the Hidaka district in Hokkaido. Group III (control) included mares (20 cases) and their newborn foals (3 cases), which were heavy horses from the Tokachi district.
Degeneration of the skeletal muscle in the aborted fetuses and premature foals (8.0 to 10.5months in fetal age) was observed in 4 cases out of 16 in Group I, but no changes were found in Groups II and III.
The serum selenium levels and blood glutathione peroxidase activity in the mares of Group I were significantly markedly lower than those of Groups II and III.
The α-tocopherol levels in the organs of the fetuses and foals in Group I and Group II were lower, particularly in the liver and adrenal gland, than in Group III. Selenium levels in the organs of the fetuses and foals in Group I were lower, particularly in the liver and kidneys, than those of Groups II and III.
In hay supplied to mares in Group I, low contents of α-tocopherol and selenium were observed. Concentrate supplied to mares of Group III showed a high content of selenium.
From these results, it was suggested that nutritional myopathy caused by selenium and tocopherol deficiencies also occurs in the late fetal period of horses.