THE USE OF THE CHICK FOR THE ASSAY OF ANDROGENS

THE BIOASSAY of androgenic material can be accurately accomplished by the measurement of the size of the combs of capons following the administration of the hormone (1).Unfortunately, it is difficult and expensive to maintain a suitable flock of birds. As will be demonstrated in a subsequent publication, the chemical methods used in the quantitative estimation of ketosteroids do not always demonstrate the androgenic activity of a biologic mixture. For these reasons an at tempt has been made to use the chick for the assay of androgens. Several reports (2–8) of similar work have already appeared in the literature. This paper includes the sig nificant findings from this laboratory after the study of about 1,500 chicks. Since our researches include the study of the amount of androgenic material in blood, we found it necessary to use the most sensitive method available. For this reason inunction was preferred to injection. In all the experiments reported here White Leghorn chicks were used.