Hereditary congenital goitre occurring only in one twin of each inbred breed of 5 goats is reported. The loss of hair on whole the body, oedema of tissues around the neck with enlarged thyroid gland in the dead newborn kids were cardinal sigs of hypothyroidism. Dams and their alive twin kids showed no perceptible clinical abnormality of their thyroids. Histopathological findings observed in sections of affected thyroids of the dead kids as well as, the thyroid functions of the still living kids and their dams suggested the view of hypofunction of the thyroid gland of the dams. There is no evidence as to whether the cases are due to simple iodine deficiency or as 4 result of a conditioned one.