The thyroid morphology and the level FCM yield were studied in 84 dam-daughter pairs discarded from the Ayrshire herd of the Viik Experimental Farm. Data was divided into three groups according to the thyroid weight of the dam: less than 30 g in group I. from 30 to 50 g in group II. and 50 g or over in group III. https://www.animationbengal.com/