Colostrum corpuscles are not always found in so-called colostrum milk; when they are present, the percentage of proteids is higher; as they disappear, the proteid percentage drops.
The color of colostrum milk is yellow; this color is especially marked in negroes' milk (observed in four cases not included in this report).
The reaction of colostrum milk is alkaline.
The specific gravity varies from 1024 to 1034. This variation is chiefly due to the variation in the amount of fat present.