Abstract
Studies on crystallization and cytological obser-vation of nasal-mucus smear were performed on 260 cases of improved Nipponese black cows and Holstein-Friesian cows which were bred in the suburbs of Tottori from May, 1955, to December, 1956.
The data obtained can be summarized as follows
1) The crystallization phenomen on of the nasal-mucus smear treated with silver nitrate could be found with the same crystallization pattern observed in the cervical mucus.
2) The crystallization pattern of the nasal mucus was classified into ten types.
3) The crystallization phenomen on of the nasal mucus presented an indisputed cyclic variation.
4) The cellular content observed was composed mainly of epithelial cells, thin neutrophile leucocytes, lymphocytes, eosinophile leucocytes, and monocytes. In the estrus these cells made their appearance in a larger number in the cellular content than in the other stages of the sexual cycle.
