On the development of the thyroid weight in the dairy herd of the Viik experimental farm

Authors

• Vappu Kossila Department of Animal Husbandry, University of Helsinki

DOI: https://doi.org/10.23986/afsci.71734

Abstract

The mean thyroid weight of the growing (under 60 months old) and full-grown (over 60 months old) cows slaughtered from the Ayrshire herd of the Viik Experimental Farm during the years 1958—59 (I), 1960—65 (II) and 1966—69 (III) was as follows: 24.46 and 43.10 g (I), 21.02 and 30.16 (II) and 18.16 and 27.01 g (III) respectively. Decrease in the thyroid weight from (I) to (III) was believed to be due to the adding of iodine as a component of a mineral salt mixture into the ration of the herd in 1959. The thyroid weights of young cattle and bulls showed trends similar to those observed in cows.