Students of human thyroid disease will be interested in a series of observations with respect to the iodin requirement of pregnant animals reported from the field of animal husbandry. It is known that a large percentage of the sows in certain sections of the Northwest have given birth to hairless and otherwise defective young. Many of these pigs are born dead; others die in an hour or two, and few live more than twenty-four to thirty-six hours. The resulting loss in Montana amounts to about 1,000,000 young pigs annually. While the loss is heaviest among swine, there are numerous cases among sheep, and occasionally among cattle and horses.
The affected pigs are carried to the full term of gestation period, and though of full size are strikingly weak and low in vitality. Most noticeable in the appearance of a typical specimen is the absence of hair. Except for a few